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1.
Plant Dis ; 100(9): 1880-1888, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30682984

RESUMO

The effect of irrigation frequency (daily [T1], biweekly [T2], and dryland [T3]) on Verticillium wilt of olive was studied in two fields that were naturally infested with Verticillium dahliae in southern Spain and planted to 'Picual' olive. Disease onset (average 61 weeks after planting) and disease incidence (average 75.6%) did not differ among irrigation treatments in both fields. Irrigation consistently increased disease development regarding dryland treatment, but this effect varied over time. In experiment I, T1, the relative area under the disease progress curve was greater on all recording dates (ranging from 15.8 to 33.7) in comparison with T3 (average 6.6). Data for experiment II were similar to this on the most favorable dates for disease (March to April). The T2 treatment value varied over time depending on the season and experimental field, being difficult to differentiate from the values of T1 and T3. Significant correlation between disease incidence and severity increments during spring and fall with the soil water content of the same or previous favorable seasons was observed. Through these correlations, we detected soil water contents of 24.3% (experiment I) and 23.6% (experiment II), where the increments of disease parameters remained at zero. Therefore, scheduling irrigation treatments based on rainfall may be a feasible method for maintaining the soil moisture below levels that favor for disease development.

2.
Plant Dis ; 99(4): 488-495, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30699544

RESUMO

The influence of irrigation frequency on the onset and development of Verticillium wilt of olive (VWO) was studied. A split-plot design in microplots with naturally infested soil was established for studying four irrigation frequencies for three olive cultivars with differing levels of disease resistance. Final disease incidence (DI) and mortality in 'Picual' plants subjected to daily irrigation treatment (T1) reached values of 100 and 63%, respectively. For Picual-T1 samples, the area under the disease progress curve values were significantly different between 15 December 2012 and 15 July 2013 (14.8 to 42.8%) compared with the average results of the other treatments, which were weekly (T2), biweekly (T3), and deficit (T4) (0.4 to 11.5%). No significant differences between the irrigation treatments were observed in 'Arbequina', although the DI progressed consistently (60% in all treatments). In 'Frantoio', little disease developed. We conclude that a daily irrigation treatment encourages VWO development in susceptible Picual. Therefore, in susceptible cultivars growing in infested soils under daily irrigation regimes, the extension of irrigation frequency may reduce disease incidence. In the context of an integrated control, the use of resistant cultivars seems to be more relevant than the detrimental effects observed in frequent irrigation schedules.

3.
Plant Dis ; 97(5): 668-674, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-30722191

RESUMO

The resistance of 11 olive cultivars to Verticillium dahliae was assessed in two experimental field trials. One-year-old rooted olive cuttings from the World Olive Germplasm Bank (IFAPA research center, Córdoba, Spain) were planted in a heavily infested field in Utrera (Sevilla province) and in a moderately infested field in Andújar (Jaén province) of southern Spain. Plants were assessed for Verticillium wilt resistance during 22 months based on disease severity and tree growth. Severe disease symptoms were observed 6 months after planting in both trials. Twenty months after planting in the heavily infested soil, V. dahliae had killed nearly all of the trees of 'Bodoquera', 'Cornicabra', 'Manzanilla de Sevilla', and 'Picual', demonstrating the elevated risk of planting susceptible cultivars in a soil heavily infested with V. dahliae. 'Arbequina', 'Koroneiki', 'Sevillenca', and especially 'Frantoio', 'Empeltre', and 'Changlot Real' showed a high level of disease resistance. However, all of them were affected by the disease. Although the field results confirmed the level of resistance previously obtained for these olive genotypes under controlled conditions, there were some discrepancies. This information will be useful in managing the disease and also in selecting new cultivars for the breeding of Verticillium wilt resistance.

4.
Microbiol Resour Announc ; 10(12)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766897

RESUMO

A near-complete genome sequence was obtained for a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern (VOC) 202012/01 strain obtained from an oropharyngeal swab sample from a Peruvian patient with coronavirus syndrome who had contact with an individual who had recently returned from England.

5.
Int J Neural Syst ; 30(1): 1950019, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31522594

RESUMO

Working memory (WM) is a crucial cognitive process and its disruption is among the earliest symptoms of Alzheimer's disease. While alterations of the neuronal processes underlying WM have been evidenced in mild cognitive impairment (MCI), scarce literature is available in subjective cognitive decline (SCD). We used magnetoencephalography during a WM task performed by MCI (n = 45), SCD (n = 49) and healthy elders (n = 49) to examine group differences during the maintenance period (0-4000ms). Data were analyzed using time-frequency analysis and significant oscillatory differences were localized at the source level. Our results indicated significant differences between groups, mainly during the early maintenance (250-1250ms) in the theta, alpha and beta bands and in the late maintenance (2750-3750ms) in the theta band. MCI showed lower local synchronization in fronto-temporal cortical regions in the early theta-alpha window relative to controls (p = 2 × 10-03) and SCD (p = 4 × 10-03), and in the late theta window relative to controls (p = 1 × 1003) and SCD (p = 0.01). Early theta-alpha power was significantly correlated with memory scores (rho = 0.24,p = 0.02) and late theta power was correlated with task performance (rho = 0.24,p = 0.03) and functional activity scores (rho = -0.23,p = 0.02). In the early beta window, MCI showed reduced power in temporo-posterior regions relative to controls (p = 3 × 10-03) and SCD (p = 0.02). Our results may suggest that these alterations would reflect that memory-related networks are damaged.


Assuntos
Envelhecimento/fisiologia , Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Disfunção Cognitiva/fisiopatologia , Sincronização Cortical/fisiologia , Magnetoencefalografia , Memória de Curto Prazo/fisiologia , Análise e Desempenho de Tarefas , Idoso , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Masculino
6.
Appl Ergon ; 82: 102981, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31670156

RESUMO

In the present research, models based on multivariate adaptive regression splines (MARS) are proposed to study the influence of gender in the factors affecting the development of shoulders, neck and upper limb MSD. Two different MARS models, corresponding to men and women, are constructed to identify variables with the strongest effect on the target MSD. Both models are capable to predict successfully the occurrence of the studied disorders. Men seem to be more vulnerable to physical risk factors and some other working conditions, whereas women appear to be more affected by psychosocial risk factors and activities carried out outside their working hours. According to the results, gender needs to be considered to ensure the success and effectiveness of ergonomic interventions on the whole working population.


Assuntos
Doenças Musculoesqueléticas/fisiopatologia , Pescoço/fisiopatologia , Doenças Profissionais/fisiopatologia , Ombro/fisiopatologia , Extremidade Superior/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários
7.
Behav Neurol ; 2018: 9684129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29808100

RESUMO

Frontotemporal dementia (FTD) affects behavior, language, and personality. This study aims to explore functional connectivity changes in three FTD variants: behavioral (bvFTD), semantic (svPPA), and nonfluent variant (nfvPPA). Seventy-six patients diagnosed with FTD by international criteria and thirty-two controls were investigated. Functional connectivity from resting functional magnetic resonance imaging (fMRI) was estimated for the whole brain. Two types of analysis were done: network basic statistic and topological measures by graph theory. Several hubs in the limbic system and basal ganglia were compromised in the behavioral variant apart from frontal networks. Nonfluent variants showed a major disconnection with respect to the behavioral variant in operculum and parietal inferior. The global efficiency had lower coefficients in nonfluent variants than behavioral variants and controls. Our results support an extensive disconnection among frontal, limbic, basal ganglia, and parietal hubs.


Assuntos
Afasia Primária Progressiva/fisiopatologia , Conectoma/métodos , Demência Frontotemporal/fisiopatologia , Rede Nervosa/fisiopatologia , Idoso , Afasia Primária Progressiva/diagnóstico por imagem , Feminino , Demência Frontotemporal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Afasia Primária Progressiva não Fluente/diagnóstico por imagem , Afasia Primária Progressiva não Fluente/fisiopatologia
8.
Curr Biol ; 7(3): R186-95, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9162486

RESUMO

Limb development is a complex process involving precise control of both patterning and growth. Great strides have been made in understanding limb morphogenesis and identifying essential patterning genes in Drosophila. Differential expression of these genes divides the future limb into territories, which will give rise to different regions of the adult appendage. Recent analyses have defined the role of territorial boundaries as organizers of both patterning and growth, highlighting the connection between these two processes. The organizing activity of territorial boundaries seems to be mediated through the activity of two locally produced morphogens: Wingless and Decapentaplegic. We propose a model in which these two molecules, distributed in a graded fashion, act in synergy to promote growth of the entire appendage. We also suggest that existence of growth inhibitors that counteract the action of Wingless and Decapentaplegic; by opposing the gradient of these growth factors, the inhibitors guide the near-uniform proliferation that shapes the imaginal discs from which the adult appendages are formed in Drosophila.


Assuntos
Proteínas de Drosophila , Extremidades/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/fisiologia , Animais , Animais Geneticamente Modificados , Diferenciação Celular , Linhagem da Célula , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/ultraestrutura , Embrião não Mamífero/citologia , Embrião não Mamífero/ultraestrutura , Indução Embrionária , Extremidades/crescimento & desenvolvimento , Genes de Insetos , Proteínas de Insetos/genética , Larva/citologia , Larva/ultraestrutura , Modelos Biológicos , Morfogênese/genética , Especificidade de Órgãos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Transgenes , Asas de Animais/citologia , Asas de Animais/embriologia , Asas de Animais/crescimento & desenvolvimento , Proteína Wnt1
9.
Plant Methods ; 13: 55, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694843

RESUMO

BACKGROUND: Tree pruning is a costly practice with important implications for crop harvest and nutrition, pest and disease control, soil protection and irrigation strategies. Investigations on tree pruning usually involve tedious on-ground measurements of the primary tree crown dimensions, which also might generate inconsistent results due to the irregular geometry of the trees. As an alternative to intensive field-work, this study shows a innovative procedure based on combining unmanned aerial vehicle (UAV) technology and advanced object-based image analysis (OBIA) methodology for multi-temporal three-dimensional (3D) monitoring of hundreds of olive trees that were pruned with three different strategies (traditional, adapted and mechanical pruning). The UAV images were collected before pruning, after pruning and a year after pruning, and the impacts of each pruning treatment on the projected canopy area, tree height and crown volume of every tree were quantified and analyzed over time. RESULTS: The full procedure described here automatically identified every olive tree on the orchard and computed their primary 3D dimensions on the three study dates with high accuracy in the most cases. Adapted pruning was generally the most aggressive treatment in terms of the area and volume (the trees decreased by 38.95 and 42.05% on average, respectively), followed by trees under traditional pruning (33.02 and 35.72% on average, respectively). Regarding the tree heights, mechanical pruning produced a greater decrease (12.15%), and these values were minimal for the other two treatments. The tree growth over one year was affected by the pruning severity and by the type of pruning treatment, i.e., the adapted-pruning trees experienced higher growth than the trees from the other two treatments when pruning intensity was low (<10%), similar to the traditionally pruned trees at moderate intensity (10-30%), and lower than the other trees when the pruning intensity was higher than 30% of the crown volume. CONCLUSIONS: Combining UAV-based images and an OBIA procedure allowed measuring tree dimensions and quantifying the impacts of three different pruning treatments on hundreds of trees with minimal field work. Tree foliage losses and annual canopy growth showed different trends as affected by the type and severity of the pruning treatments. Additionally, this technology offers valuable geo-spatial information for designing site-specific crop management strategies in the context of precision agriculture, with the consequent economic and environmental benefits.

10.
Cancer Res ; 47(22): 5883-7, 1987 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-3664489

RESUMO

Estrogens stimulate growth of MCF-7 breast cancer cells in monolayer culture. Possible interference of serum factors leading to an estrogen-insensitive cell growth was analyzed in various experiments carried out on serum batches producing no estradiol stimulation. Out of five estrogen conjugates, only 3-glucurono-estradiol partly suppressed the inhibition of hydroxytamoxifen; the conjugate also reduced the estrogen receptor content of the cells, probably by a down regulation process ("processing"). Moreover, prolonged subcultures in dextran-coated charcoal-treated serum attempting to remove possible intracellular estrogens produced no growth stimulation. Interference by hormone carriers of the serum was ruled out by the fact that two strong synthetic estrogens, moxestrol and diethylstilbestrol with weak binding affinity for these carriers, were unstimulatory. Reduction of the carrier concentration also failed to confer any estrogen sensitivity. This lack of effect of most estrogen conjugates and serum carriers seems to contradict the hypothesis of their interference leading to an estrogen-insensitive growth. Presence in the serum of potential inhibitors towards estrogen action was also examined. Dilution of sera inducing an estrogenic stimulated growth failed to show any growth increase, either in the absence or presence of estradiol, thus excluding the possibility of a major influence of an antagonism on growth control. Moreover, clonogenic assays in soft agar eliminated the hypothesis that a difference between "active" (stimulatory with estradiol) and "inactive" serum batches may result from distinct adherence properties rather than from real growth stimulation. All of these data are consistent with the concept that serum factors which are not of estrogenic nature mediate the trophic effect of estradiol; their absence in some serum batches may lead to an estrogen-insensitive cell growth.


Assuntos
Neoplasias da Mama/patologia , Estrogênios/farmacologia , Animais , Sangue , Bovinos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Meios de Cultura , Congêneres do Estradiol/farmacologia , Feminino , Feto , Humanos , Relação Estrutura-Atividade
11.
Sci Rep ; 6: 37685, 2016 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-27883082

RESUMO

The consideration of Subjective Cognitive Decline (SCD) as a preclinical stage of AD remains still a matter of debate. Alpha band alterations represent one of the most significant changes in the electrophysiological profile of AD. In particular, AD patients exhibit reduced alpha relative power and frequency. We used alpha band activity measured with MEG to study whether SCD and MCI elders present these electrophysiological changes characteristic of AD, and to determine the evolution of the observed alterations across AD spectrum. The total sample consisted of 131 participants: 39 elders without SCD, 41 elders with SCD and 51 MCI patients. All of them underwent MEG and MRI scans and neuropsychological assessment. SCD and MCI patients exhibited a similar reduction in alpha band activity compared with the no SCD group. However, only MCI patients showed a slowing in their alpha peak frequency compared with both SCD and no SCD. These changes in alpha band were related to worse cognition. Our results suggest that AD-related alterations may start in the SCD stage, with a reduction in alpha relative power. It is later, in the MCI stage, where the slowing of the spectral profile takes place, giving rise to objective deficits in cognitive functioning.


Assuntos
Ritmo alfa/fisiologia , Doença de Alzheimer/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Magnetoencefalografia , Idoso , Demografia , Feminino , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Modelos Lineares , Masculino , Testes Neuropsicológicos , Tamanho do Órgão
12.
J Biomed Mater Res B Appl Biomater ; 74(2): 718-24, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15977312

RESUMO

In a composite prosthesis, the component placed at the peritoneal interface takes the form of a physical or chemical barrier. In this experimental study performed on the white New Zealand rabbit, several composites were examined to establish the effectiveness of these barriers at impeding adhesion formation. The biomaterials tested were two polypropylene prostheses (PP) with the physical barriers of expanded polytetrafluoroethylene or polyurethane (PP + ePTFE and PP + PU) and two prostheses (one polyester and the other PP) with the absorbable chemical barriers of polyethylene glycol/glycerol and hyaluronate, respectively (PO + gl and PP + hy). The composites were used to repair 7 x 5 cm defects created in the abdominal wall of the animals by placing the implant in contact with the visceral peritoneum and the subcutaneous tissue and fixing it to recipient tissue by 4/0 polypropylene running suture. Fourteen days after surgery the animals were sacrificed and specimens were taken for light microscopy and scanning electron microscopy. Adhesions developing at the prosthesis/visceral peritoneal interface were quantified. All the prostheses induced optimal mesothelialization. Composites with physical barriers behaved similarly in terms of provoking adhesions. However, the prostheses with chemical barriers differed in their effectiveness at preventing adhesions. Overall, the best results were obtained with the PP + PU composite.


Assuntos
Parede Abdominal , Materiais Biocompatíveis , Próteses e Implantes , Animais , Glicerol , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Varredura , Poliésteres , Polietilenoglicóis , Polipropilenos , Poliuretanos , Coelhos
13.
Hernia ; 9(4): 338-43, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16132190

RESUMO

The component of a composite prosthesis, which makes contact with the visceral peritoneum, can be reabsorbable or non-reabsorbable, and laminar or reticular. This study was designed to determine whether the composition of this second, barrier component could improve its behavior at this interface. Abdominal wall defects in rabbits were repaired using a polypropylene prosthesis (PP), or the composites Sepramesh (PP + h) or Vicryl (PP + v). Fourteen days after surgery, the implants were evaluated by light and scanning electron microscopy, and immunohistochemistry. Prosthetic areas occupied by adhesions (PP: 71.08 +/- 5.09, PP + h: 18.55 +/- 4.96, P + v: 69.69 +/- 16.81%), neoperitoneal thickness (PP: 256.17 +/- 21.68, PP + h: 83.11 +/- 19.63, PP + v:213.72 +/- 35.90 microm) and macrophage counts (PP: 8.73 +/- 1.16, PP + h: 27.33 +/- 4.13, PP + v: 31.24 +/- 3.08%) showed significant differences (P < 0.05). The tested biomaterials induced an optimal recipient tissue infiltration. Least adhesion formation was observed on the PP + h implants. This suggests that the second component, although reabsorbable, should be smooth in structure.


Assuntos
Parede Abdominal/cirurgia , Próteses e Implantes , Aderências Teciduais/prevenção & controle , Animais , Materiais Revestidos Biocompatíveis , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Varredura , Poliglactina 910 , Polipropilenos , Coelhos , Estatísticas não Paramétricas , Técnicas de Sutura
15.
Microb Drug Resist ; 7(1): 33-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11310801

RESUMO

A nationwide multicenter study (including 25 laboratories) of the antimicrobial susceptibility of bacterial pathogens commonly associated with community-acquired lower respiratory tract infections (LRTI), with testing undertaken in a central laboratory, was conducted in Portugal in 1999. Antimicrobial resistance in Haemophilus influenzae has not increased in the last decade. Of the 498 isolates tested, 12.4% produced beta-lactamase and >95% were susceptible to all antimicrobials except ampicillin. In contrast, there was a rapid increase of resistance in Streptococcus pneumoniae. Of the 312 isolates tested, 24.7% exhibited decreased susceptibility to penicillin (13.5% showed low-level and 11.2% high-level resistance), 13.8% were resistant to erythromycin, clarithromycin and azithromycin, and 13.6% to cefuroxime and to tetracycline. Of the 38 Moraxella catarrhalis tested, 81.6% produced beta-lactamase. Resistance to penicillin, cefuroxime, erythromycin, clarithromycin, and azithromycin in S. pneumoniae and beta-lactamase production in H. influenzae were significantly higher in pediatric patients than in adults. Overall, amoxycillin/clavulanate was the most active antimicrobial agent in vitro against H. influenzae, S. pneumoniae, and M. catarrhalis isolated from patients with community-acquired LRTI in Portugal.


Assuntos
Haemophilus influenzae/efeitos dos fármacos , Moraxella catarrhalis/efeitos dos fármacos , Infecções Respiratórias/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Adulto , Criança , Infecções Comunitárias Adquiridas/microbiologia , Resistência Microbiana a Medicamentos , Haemophilus influenzae/enzimologia , Humanos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/enzimologia , Portugal , Infecções Respiratórias/epidemiologia , Streptococcus pneumoniae/enzimologia , beta-Lactamases/análise , beta-Lactamases/metabolismo
16.
Microb Drug Resist ; 9(1): 73-80, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12705685

RESUMO

A nationwide multicenter study (including 31 laboratories) of the antimicrobial susceptibility of 1210 Streptococcus pneumoniae isolates from patients with community-acquired lower respiratory tract infections (LRTI) was carried out over 3 years (1999-2001) in Portugal. Testing of all isolates was undertaken in a central laboratory. Overall macrolide resistance was 13.1%. Decreased susceptibility to penicillin was 24.5% (15.5% low-level and 9.0% high-level resistance). Taken into consideration, the resistance rates reported in a previous surveillance study of 1989-1993, a six-fold increase of erythromycin resistance in the last decade was documented. Resistance to erythromycin, clarithromycin, and azithromycin was higher in pediatric patients than in adults. The overwhelming majority (82.3%) of macrolide-resistant isolates were multidrug resistant, although 44.9% were fully susceptible to penicillin. Most macrolide-resistant isolates (80.4%) showed the MLSB phenotype (76.6% MLSB-constitutive resistance, and 3.8% MLSB-inducible resistance) and were also resistant to clindamycin, tetracycline, and co-trimoxazole. The M phenotype was seen in 19.6% isolates and these had MIC90 values of 8 mg/L for erythromycin and clarithromycin, and of 12 mg/L for azithromycin. The clinical significance of macrolide resistance in the management of LRTI is discussed. Because of the specific situation concerning macrolide resistance described in S. pneumoniae, careful use of macrolide antibiotics in therapy and cautious monitoring of macrolide resistance should be continued in Portugal.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções Respiratórias/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Adulto , Portador Sadio , Criança , Infecções Comunitárias Adquiridas/microbiologia , Genótipo , Humanos , Macrolídeos , Testes de Sensibilidade Microbiana , Portugal , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
17.
Artif Intell Med ; 22(3): 233-48, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11377149

RESUMO

Combining the predictions of a set of classifiers has shown to be an effective way to create composite classifiers that are more accurate than any of the component classifiers. There are many methods for combining the predictions given by component classifiers. We introduce a new method that combine a number of component classifiers using a Bayesian network as a classifier system given the component classifiers predictions. Component classifiers are standard machine learning classification algorithms, and the Bayesian network structure is learned using a genetic algorithm that searches for the structure that maximises the classification accuracy given the predictions of the component classifiers. Experimental results have been obtained on a datafile of cases containing information about ICU patients at Canary Islands University Hospital. The accuracy obtained using the presented new approach statistically improve those obtained using standard machine learning methods.


Assuntos
Algoritmos , Inteligência Artificial , Unidades de Terapia Intensiva/estatística & dados numéricos , Teorema de Bayes , Árvores de Decisões , Genética/estatística & dados numéricos , Humanos , Sistemas Computadorizados de Registros Médicos , Planejamento de Assistência ao Paciente
18.
Braz J Med Biol Res ; 34(10): 1227-35, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11593296

RESUMO

Preeclampsia is the main cause of maternal mortality and is associated with a five-fold increase in perinatal mortality in developing countries. In spite of this, the etiology of preeclampsia is unknown. The present article analyzes the contradictory results of the use of calcium supplementation in the prevention of preeclampsia, and tries to give an explanation of these results. The proposal of an integrative model to explain the clinical manifestations of preeclampsia is discussed. In this proposal we suggest that preeclampsia is caused by nutritional, environmental and genetic factors that lead to the creation of an imbalance between the free radicals nitric oxide, superoxide and peroxynitrate in the vascular endothelium. The adequate interpretation of this model would allow us to understand that the best way of preventing preeclampsia is the establishment of an adequate prenatal control system involving adequate antioxidant vitamin and mineral supplementation, adequate diagnosis and early treatment of asymptomatic urinary and vaginal infections. The role of infection in the genesis of preeclampsia needs to be studied in depth because it may involve a fundamental change in the prevention and treatment of preeclampsia.


Assuntos
Pré-Eclâmpsia/etiologia , Cálcio da Dieta/administração & dosagem , Citocinas/sangue , Citocinas/fisiologia , Fibras na Dieta/efeitos adversos , Suplementos Nutricionais , Feminino , Humanos , Infecções/complicações , Inflamação/complicações , Óxido Nítrico/biossíntese , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Gravidez , Fatores de Risco , Fatores Socioeconômicos , Superóxidos
19.
Acta Med Port ; 14(5-6): 459-68, 2001.
Artigo em Português | MEDLINE | ID: mdl-11878155

RESUMO

The Viriato Study is a nationwide, multicenter prospective study of the antimicrobial susceptibility of bacterial pathogens commonly associated with community-acquired respiratory tract infections in Portugal. In 2000, 28 laboratories participated in the study with a total of 1071 strains, with testing undertaken in a central laboratory. Of the 213 Streptococcus pyogenes strains isolated from patients with acute tonsillitis, all were susceptible to penicillin, amoxicillin/clavulanate and cefuroxime, but 21.1% were resistant to erythromycin, clarithromycin, azithromycin and 16.4% to tetracycline. From patients with lower respiratory tract infection, 403 strains of Haemophilus influenzae, 366 of Streptococcus pneumoniae and 89 of Moraxella catarrhalis were studied. 13.1% of H. influenzae and 94.4% of M. catarrhalis produced beta-lactamase. Among S. pneumoniae isolates, 25.1% were resistant to penicillin (8.8% showing high-level resistance), 14.5% to tetracycline, 12.8% to erythromycin, clarithromycin and azithromycin, and 10.1% to cefuroxime. Overall, penicillin was the most active antimicrobial against S. pyogenes and amoxycillin/clavulanate the most active in vitro simultaneously against H. influenzae, S. pneumoniae and M. catarrhalis isolated from patients with community-acquired LRTI in Portugal.


Assuntos
Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Moraxella catarrhalis/efeitos dos fármacos , Infecções por Neisseriaceae/microbiologia , Pneumonia Bacteriana/microbiologia , Pneumonia Pneumocócica/microbiologia , Infecções Respiratórias/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Infecções Comunitárias Adquiridas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Estudos Prospectivos
20.
Acta Med Port ; 12(4-6): 169-76, 1999.
Artigo em Português | MEDLINE | ID: mdl-10481318

RESUMO

Over a 4-year period, 2020 Staphylococcus aureus strains isolated in Santa Maria Hospital were studied, 26.3% of which were methicillin-resistant (MRSA). The main specimens from which the strains were isolated included pus, blood and sputum/bronchial secretions. Isolation in blood cultures was the most common source among patients from medical units. Antimicrobial susceptibility studies showed that while in methicillin susceptible strains sensitivity to other antimicrobial agents (apart from penicillin resistance) was the rule, in MRSA strains there was resistance to most antibiotics. Only vancomycin was active against all strains. Phage typing showed that 75.5% of the strains were typable with phages at 100 x R.T.D. Among methicillin sensitive strains, a big diversity of phage patterns was observed, including phage groups I, II, III and V, as well as with phage association D11/95. The large majority of MRSA strains were lysed by group III phages, although several distinct patterns were observed. Within these strains, lysis by groups II and V phages was not observed. Plasmid profiling was the least discriminant issue in the characterization of these micro-organisms because most of the strains harboured only one plasmid (or none). These results showed that a dominant MRSA strain did not exist in this hospital, but rather several distinct strains. The importance, as well as the difficulties in controlling the spread of MRSA strains in the present conditions of high prevalence, are highlighted.


Assuntos
Secreções Corporais/microbiologia , Líquidos Corporais/microbiologia , Staphylococcus aureus/isolamento & purificação , Tipagem de Bacteriófagos , Hospitais com mais de 500 Leitos , Hospitais Gerais , Humanos , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Plasmídeos/classificação , Portugal , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
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