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1.
Infect Dis Ther ; 13(5): 1019-1035, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38578515

RESUMO

INTRODUCTION: Infection with hepatitis A virus (HAV) is often asymptomatic in young children, but most adolescents and adults will have symptoms ranging from nausea and tiredness to acute liver failure and even death. The risk of severe disease is higher in older adults and people with pre-existing liver disease. Immunization is recommended in regions with low HAV endemicity levels, i.e., where people get infected later in life. In the Philippines, recent epidemiologic data on HAV infection are lacking. The objective of this study was to assess age-specific seroprevalence and evaluate risk factors associated with HAV seropositivity. METHODS: People from two geographic areas (urban and rural) were recruited/enrolled and stratified by age group. HAV-specific immunoglobulin G (IgG) antibodies were measured with a chemiluminescent microparticle immunoassay. Sociodemographic parameters, hepatitis medical history, disease knowledge, hygiene measures and sanitation were assessed via a purpose-made questionnaire. Age at midpoint of population immunity (AMPI) was estimated using Kaplan-Meier curves. Logistic regression analyses were carried out to determine factors that were statistically significantly associated (p < 0.05) with HAV seropositivity. RESULTS: Overall, 1242 participants were included in the analysis; 250/602 (41.5%) participants from urban regions and 283/640 (44.2%) participants from rural regions tested positive for HAV IgG antibodies. AMPI was 35 and 37 years for the rural and urban region, respectively. Higher education was associated with lower HAV seropositivity prevalence ratios, while not living in the same region for the last 5 years, regularly consuming street food and lack of handwashing after defecation were associated with a higher likelihood of HAV seropositivity. CONCLUSION: Results suggest that HAV endemicity is low in the Philippines. Factors associated with HAV seropositivity were traveling, consuming street food and lack of basic hygienic gestures. Immunization might be an option to protect vulnerable populations against severe hepatitis A disease.


Hepatitis A virus (HAV) is transmitted via the fecal-oral route through consumption of contaminated food or water or by close contact with an infected person. In children, HAV is usually of no concern, but in adults and people with existing liver disease, HAV infection can lead to severe symptoms and even death. In areas where most people get hepatitis during childhood (high endemicity), vaccination is not required, since people acquire life-long immunity after infection. In regions with low and intermediate HAV endemicity, people may remain at risk of infection later in life and vaccination could be considered to prevent severe HAV disease and its associated complications. In the Philippines, the current endemicity level is unknown. The goal of this study was to determine the endemicity level in the Philippines and to determine risk factors for HAV infection. We measured the proportion of people (by age group) who had previously been infected with HAV. Results showed that by age of 5 years < 20% of the study population was infected by HAV. By the age of 37 years in the urban population and 35 years in the rural population, 50% of people tested positive for HAV antibodies, indicating previous infection. This means that the Philippines has low HAV endemicity. Risk factors for HAV seropositivity were traveling, regularly eating street food and not washing hands after defecation. Vaccination against HAV might be of benefit in the Philippines, especially early in life to prevent most severe outcomes in adulthood.

2.
Heliyon ; 10(4): e26703, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38434012

RESUMO

The crystallographic, optical, and electrical properties of manganese sulfide thin films depend on the control of the temperature precursors in the synthesis process, as shown by the results of this work. MnS thin films were deposited on glass substrates using the SILAR method and over an additional layer of CdS synthesized by chemical bath deposition (CBD) to acquire a p-n heterojunction. SILAR is an inexpensive method performed with a homemade robot in this case. Temperature in the solution precursors varied from 20 to 80 °C in four experiments. The morphology and structure of MnS and FTO/CdS/MnS thin films were studied through scanning electron microscopy (SEM) and grazing-incidence X-ray diffraction (GIXRD); the results indicate that materials showed a polycrystalline behavior, a diffraction peak of α- MnS cubic phase was observed with lattice constants values, ranging from 4.74 to 4.75 Å. Additionally, Raman spectroscopy showed a signal corresponding to the transversal optical phonons of MnS at a wavenumber near 300 cm-1. UV-vis spectroscopy showed optical bandgap values of 3.94, 4.0, 4.09, and 4.26 eV for thin films obtained at 20°, 40°, 60°, and 80 °C. respectively. Results indicated 80 °C as an optimal cationic precursor process temperature, achieving optical transmittance T% and good film quality according to SEM and GIXRD for the synthetization of MnS. The current-voltage (I-V) characterization in the heterojunction showed a characteristic diode curve with an open circuit voltage (VOC) of 300 mV under illumination, which indicated that the manganese sulfide behaves as p-type material contributing with positive charge carriers, while CdS behaves as n-type material.

3.
Sensors (Basel) ; 24(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38544207

RESUMO

The remote monitoring of vital signs and healthcare provision has become an urgent necessity due to the impact of the COVID-19 pandemic on the world. Blood oxygen level, heart rate, and body temperature data are crucial for managing the disease and ensuring timely medical care. This study proposes a low-cost wearable device employing non-contact sensors to monitor, process, and visualize critical variables, focusing on body temperature measurement as a key health indicator. The wearable device developed offers a non-invasive and continuous method to gather wrist and forehead temperature data. However, since there is a discrepancy between wrist and actual forehead temperature, this study incorporates statistical methods and machine learning to estimate the core forehead temperature from the wrist. This research collects 2130 samples from 30 volunteers, and both the statistical least squares method and machine learning via linear regression are applied to analyze these data. It is observed that all models achieve a significant fit, but the third-degree polynomial model stands out in both approaches. It achieves an R2 value of 0.9769 in the statistical analysis and 0.9791 in machine learning.


Assuntos
Temperatura Corporal , Dispositivos Eletrônicos Vestíveis , Humanos , Punho/fisiologia , Temperatura , Pandemias
4.
Radiat Prot Dosimetry ; 199(15-16): 1877-1882, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819321

RESUMO

This work presents Chameleon, a cloud computing (CC) Industry 4.0 (I4) neutron spectrum unfolding code. The code was designed under the Python programming language, using Streamlit framework®, and it is executed on the cloud, as I4 CC technology through internet, by using mobile devices with internet connectivity and a web navigator. In its first version, as a proof of concept, the SPUNIT algorithm was implemented. The main functionalities and the preliminary tests performed to validate the code are presented. Chameleon solves the neutron spectrum unfolding problem and it is easy, friendly and intuitive. It can be applied with success in various workplaces. More validation tests are in progress. Future implementations will include improving the graphical user interface, inserting other algorithms, such as GRAVEL, MAXED and neural networks, and implementing an algorithm to estimate uncertainties in the calculated integral quantities.


Assuntos
Algoritmos , Computação em Nuvem , Redes Neurais de Computação , Internet , Nêutrons
5.
Sensors (Basel) ; 23(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37571718

RESUMO

At present, modern society is experiencing a significant transformation. Thanks to the digitization of society and manufacturing, mainly because of a combination of technologies, such as the Internet of Things, cloud computing, machine learning, smart cyber-physical systems, etc., which are making the smart factory and Industry 4.0 a reality. Currently, most of the intelligence of smart cyber-physical systems is implemented in software. For this reason, in this work, we focused on the artificial intelligence software design of this technology, one of the most complex and critical. This research aimed to study and compare the performance of a multilayer perceptron artificial neural network designed for solving the problem of character recognition in three implementation technologies: personal computers, cloud computing environments, and smart cyber-physical systems. After training and testing the multilayer perceptron, training time and accuracy tests showed each technology has particular characteristics and performance. Nevertheless, the three technologies have a similar performance of 97% accuracy, despite a difference in the training time. The results show that the artificial intelligence embedded in fog technology is a promising alternative for developing smart cyber-physical systems.

6.
Medicina (Kaunas) ; 55(11)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731539

RESUMO

Diabetic foot ulcers (DFUs) are the fastest growing chronic complication of diabetes mellitus, with more than 400 million people diagnosed globally, and the condition is responsible for lower extremity amputation in 85% of people affected, leading to high-cost hospital care and increased mortality risk. Neuropathy and peripheral arterial disease trigger deformities or trauma, and aggravating factors such as infection and edema are the etiological factors for the development of DFUs. DFUs require identifying the etiology and assessing the co-morbidities to provide the correct therapeutic approach, essential to reducing lower-extremity amputation risk. This review focuses on the current treatment strategies for DFUs with a special emphasis on tissue engineering techniques and regenerative medicine that collectively target all components of chronic wound pathology.


Assuntos
Complicações do Diabetes/terapia , Pé Diabético/terapia , Desbridamento/métodos , Diabetes Mellitus/terapia , Pé Diabético/etiologia , Humanos , Terapia a Laser/métodos , Doenças do Sistema Nervoso Periférico/complicações , Doenças do Sistema Nervoso Periférico/etiologia , Dermatopatias/complicações
7.
Eur J Radiol ; 108: 66-77, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30396673

RESUMO

INTRODUCTION: We aimed to determine the diagnostic performance of Hounsfield Units (HUs) in selected brain region using computed tomography for the clinical diagnosis of brain death (BD). METHODS: A retrospective, case-control study design. A total of 66 subjects (22 cases, 44 controls) underwent brain tomography between January 2011 and December 2016. Inclusion criteria for cases considered patients with a CT performed within the 24 first hours of a clinical diagnosis of brain death. Exclusion criteria applied to patients with no CT scan performed before BD diagnosis. Brain-healthy-control subjects were identified from the hospital's CT scan database. We selected 12 regions for each cerebral hemisphere (4 basal ganglia; 2 regions gray matter (GM) regions; 4 white matter (WM) regions; 2 brain stem regions); two GM and WM regions in each cerebellar hemisphere, and 4 GM/WM ratios. Measurements included analysis of variance, receiver operating characteristic (ROC) curve, and of pooled effect sizes. RESULTS: 72 measures per subject were recorded. Without contrast material, the best performance was the GM/WM ratio at the basal ganglia level (AUROC = 0.893, 95% C.I. = 0.83, 0.96; p-value <.001). After contrast enhancement, the greatest AUROC value corresponded to the thalamus (AUROC = .959, 95% C.I. = .93, .99; p-value < .001). CONCLUSIONS: There is not an absolute threshold of GM-WM differentiation below which all patients are diagnosed with BD, but a group of HUs in selected brain regions, some of them with very high sensitivity and specificity to be used as early predictors of BD.


Assuntos
Morte Encefálica/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Gânglios da Base , Estudos de Casos e Controles , Feminino , Hospitalização , Hospitais Gerais , Humanos , Masculino , Neuroimagem/métodos , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Centros de Atenção Terciária , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
8.
Breast Cancer Res ; 20(1): 94, 2018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30092822

RESUMO

BACKGROUND: Thyroxine (T4) has been positively associated with tumor cell proliferation, while the effect of triiodothyronine (T3) on cell proliferation has not been well-established because it differs according to the type of cell line used. In Mexico, it has been reported that 14.5% of adult women have some type of thyroid dysfunction and abnormalities in thyroid function tests have been observed in a variety of non-thyroidal illnesses, including breast cancer (BC). These abnormalities might change with body mass index (BMI) because thyroid hormones are involved in the regulation of various metabolic pathways and probably by menopausal status because obesity has been negatively associated with BC in premenopausal women and has been positively associated with BC in postmenopausal women. METHODS: To assess the association between serum thyroid hormone concentration (T4 and T3) and BC and the influence of obesity as an effect modifier of this relationship in premenopausal and postmenopausal women, we measured serum thyroid hormone and thyroid antibody levels in 682 patients with incident breast cancer (cases) and 731 controls, who participated in a population-based case-control study performed from 2004 to 2007 in three states of Mexico. We tested the association of total T4 (TT4) and total T3 (TT3) stratifying by menopausal status and body mass index (BMI), and adjusted for other health and demographic risk factors using logistic regressions models. RESULTS: Higher serum total T4 (TT4) concentrations were associated with BC in both premenopausal (odds ratio (OR) per standard deviation = 5.98, 95% CI 3.01-11.90) and postmenopausal women (OR per standard deviation = 2.81, 95% CI 2.17-3.65). In premenopausal women, the effect of TT4 decreased as BMI increased while the opposite was observed in postmenopausal women. The significance of the effect modification was marginal (p = 0.059) in postmenopausal women and was not significant in premenopausal women (p = 0.22). Lower TT3 concentrations were associated with BC in both premenopausal and postmenopausal women and no effect modification was observed. CONCLUSIONS: There is a strong association between BC and serum concentrations of TT3 and TT4; this needs to be further investigated to understand why it happens and how important it is to consider these alterations in treatment.


Assuntos
Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Obesidade/epidemiologia , Tiroxina/sangue , Tri-Iodotironina/sangue , Adulto , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Feminino , Humanos , Incidência , México/epidemiologia , Pessoa de Meia-Idade , Obesidade/sangue , Pós-Menopausa/sangue , Pré-Menopausa/sangue
9.
Appl Radiat Isot ; 117: 20-26, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27133196

RESUMO

The process of unfolding the neutron energy spectrum has been subject of research for many years. Monte Carlo, iterative methods, the bayesian theory, the principle of maximum entropy are some of the methods used. The drawbacks associated with traditional unfolding procedures have motivated the research of complementary approaches. Back Propagation Neural Networks (BPNN), have been applied with success in neutron spectrometry and dosimetry domains, however, the structure and learning parameters are factors that highly impact in the networks performance. In ANN domain, Generalized Regression Neural Network (GRNN) is one of the simplest neural networks in term of network architecture and learning algorithm. The learning is instantaneous, requiring no time for training. Opposite to BPNN, a GRNN would be formed instantly with just a 1-pass training on the development data. In the network development phase, the only hurdle is to optimize the hyper-parameter, which is known as sigma, governing the smoothness of the network. The aim of this work was to compare the performance of BPNN and GRNN in the solution of the neutron spectrometry problem. From results obtained it can be observed that despite the very similar results, GRNN performs better than BPNN.

10.
Appl Radiat Isot ; 117: 8-14, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27184345

RESUMO

The most delicate part of neutron spectrometry, is the unfolding process. The derivation of the spectral information is not simple because the unknown is not given directly as a result of the measurements. Novel methods based on Artificial Neural Networks have been widely investigated. In prior works, back propagation neural networks (BPNN) have been used to solve the neutron spectrometry problem, however, some drawbacks still exist using this kind of neural nets, i.e. the optimum selection of the network topology and the long training time. Compared to BPNN, it's usually much faster to train a generalized regression neural network (GRNN). That's mainly because spread constant is the only parameter used in GRNN. Another feature is that the network will converge to a global minimum, provided that the optimal values of spread has been determined and that the dataset adequately represents the problem space. In addition, GRNN are often more accurate than BPNN in the prediction. These characteristics make GRNNs to be of great interest in the neutron spectrometry domain. This work presents a computational tool based on GRNN capable to solve the neutron spectrometry problem. This computational code, automates the pre-processing, training and testing stages using a k-fold cross validation of 3 folds, the statistical analysis and the post-processing of the information, using 7 Bonner spheres rate counts as only entrance data. The code was designed for a Bonner Spheres System based on a 6LiI(Eu) neutron detector and a response matrix expressed in 60 energy bins taken from an International Atomic Energy Agency compilation.

11.
Chemosphere ; 144: 1256-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26476047

RESUMO

Dechlorane Plus (DP) is a flame retardant used as a substitute of Mirex since 1970s, but it was not detected in the environment until 2006. Since then, this compound and its main relatives, Dechlorane 602, 603 and 604, have been mainly studied in environmental matrices for monitoring purposes, but the dietary exposure to them has been hardly investigated so far. In the present study, we determined this family of compounds in fish and vegetable oil samples from Catalonia (Spain), most of them used as health supplements. Determination was carried out by gas chromatography-high resolution mass spectrometry (GC-HRMS), after a clean up in a multilayer silica column and preparative high performance liquid chromatography (HPLC) equipped with a pyrenyl(ethyl) column. Concentrations of Dechlorane compounds were between below the limit of detection and 384.2 pg g(-1). Although there are only few studies about the presence of these pollutants in food or feed, concentrations obtained indicated that these compounds are in the same order in fish and vegetable oil health supplements as the few other food and feed studies.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Óleos de Peixe/química , Retardadores de Chama/análise , Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Clorados/análise , Limite de Detecção , Compostos Policíclicos/análise , Espanha
12.
Nutr. hosp ; 31(3): 1394-1402, mar. 2015. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-134443

RESUMO

Introducción: Los trastornos del comportamiento alimentario (TCA) son las patologías psicológicas que más se han incrementado en los últimos años. Uno de los factores que determina la elevada prevalencia de TCA en nuestra sociedad es el gran desconocimiento sobre alimentación. Este desconocimiento puede deberse a la consulta de recursos online sin validez científica. Objetivo y ámbito: El objetivo de este trabajo ha sido analizar la calidad científica y el posicionamiento de los sitios web en español con información sobre nutrición, TCA y obesidad. Material y métodos: Se realizó una búsqueda de páginas web en el navegador Google Chrome con las palabras clave: dieta, anorexia, bulimia, nutrición y obesidad, seleccionándose los 20 primeros resultados de cada búsqueda según los índices de posicionamiento ofrecidos por SEOquake (Page Rank, Alexa Rank y SEMrush Rank). Las variables de análisis fueron: información relacionada con dietas y hábitos alimentarios, información sobre alimentación saludable, información sobre TCA y sus criterios diagnósticos e información de carácter formativo acerca de temas profesionales de salud general. Resultados: Sólo el 50% de las web encontradas cumplían los criterios de inclusión en el estudio. La mayoría no seguían las pautas establecidas por e-Europa sobre calidad. La mediana de Page Rank fue de 2, excepto en aquellas asociadas a instituciones sanitarias de prestigio. Conclusiones: Dada la escasez de webs sanitarias con rigor científico, es imprescindible la revisión de las existentes y la creación de nuevos espacios on-line cuya supervisión sea realizada por profesionales especialistas en salud y nutrición (AU)


Introduction: Eating disorders are serious psychological disorders with an increased incidence in last years. One of the factors that determine the high prevalence of eating disorders in our society is the lack of knowledge about nutrition. One of the reasons of this lack of knowledge could be the presence of online resources without scientific validity. Objective and Scope: The aim of this study was to analyze the scientific quality and positioning of websites in Spanish that have information on nutrition, eating disorders and obesity. Materials and Methods: For this purpose, a web search was conducted in the Google Chrome browser using the key words: diet, anorexia, bulimia, obesity and nutrition, and selecting the first 20 results of each search at the rates offered by SeoQuake positioning (Page Rank, AlexaRank y SEMrush Rank). The variables used for the analysis were: information related to eating habits and diets, information on healthy eating, information about eating disorders and their diagnostics, and formative information about general health topics with professional criteria. Results: Only the 50% of the webpages accomplished the inclusion criteria for this study. Most of them did not follow the guidelines established by e- Europe assessment for quality. The median of the Webpage’s PageRank was2, except those associated with health institutions. Conclusions: Given the scarcity of healthcare websites with scientific rigor is essential to review the existing one and to create new online spaces whose supervision must be carried out by specialists in health and nutrition (AU)


Assuntos
Humanos , Informação de Saúde ao Consumidor/estatística & dados numéricos , Acesso à Informação , Internet/estatística & dados numéricos , Ciências da Nutrição , Transtornos da Alimentação e da Ingestão de Alimentos , Internet , Guias como Assunto , Obesidade , Espanha , Controle de Qualidade , União Europeia , Dieta
13.
J Trauma Acute Care Surg ; 74(2): 634-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23354262

RESUMO

BACKGROUND: Several studies recommend not initiating advanced life support in traumatic cardiac arrest (TCA), mainly owing to the poor prognosis in several series that have been published. This study aimed to analyze the survival of the TCA in our series and to determine which factors are more frequently associated with recovery of spontaneous circulation (ROSC) and complete neurologic recovery (CNR). METHODS: This is a cohort study (2006-2009) of treatment benefits. RESULTS: A total of 167 TCAs were analyzed. ROSC was obtained in 49.1%, and 6.6% achieved a CNR. Survival rate by age groups was 23.1% in children, 5.7% in adults, and 3.7% in the elderly (p < 0.05). There was no significant difference in ROSC according to which type of ambulance arrived first, but if the advanced ambulance first, 9.41% achieved a CNR, whereas only 3.7% if the basic ambulance first. We found significant differences between the response time and survival with a CNR (response time was 6.9 minutes for those who achieved a CNR and 9.2 minutes for those who died). Of the patients, 67.5% were in asystole, 25.9% in pulseless electrical activity (PEA), and 6.6% in VF. ROSC was achieved in 90.9% of VFs, 60.5% of PEAs, and 40.2% of those in asystole (p < 0.05), and CNR was achieved in 36.4% of VFs, 7% of PEAs, and 2.7% of those in asystole (p < 0.05). The mean (SD) quantity of fluid replacement was greater in ROSC (1,188.8 [786.7] mL of crystalloids and 487.7 [688.9] mL of colloids) than in those without ROSC (890.4 [622.4] mL of crystalloids and 184.2 [359.3] mL of colloids) (p < 0.05). CONCLUSION: In our series, 6.6% of the patients survived with a CNR. Our data allow us to state beyond any doubt that advanced life support should be initiated in TCA patients regardless of the initial rhythm, especially in children and those with VF or PEA as the initial rhythm and that a rapid response time and aggressive fluid replacement are the keys to the survival of these patients. LEVEL OF EVIDENCE: Therapeutic study, level IV; epidemiologic study, level III.


Assuntos
Suporte Vital Cardíaco Avançado , Parada Cardíaca/terapia , Ferimentos e Lesões/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , Hidratação , Parada Cardíaca/etiologia , Parada Cardíaca/mortalidade , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/terapia
14.
J Plant Physiol ; 166(5): 467-76, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18778872

RESUMO

Geranium plants are an important part of urban green areas but suffer from drought, especially when grown in containers with a limited volume of medium. In this experiment, we examined the response of potted geraniums to different irrigation levels. Geranium (Pelargoniumxhortorum L.) seedlings were grown in a growth chamber and exposed to three irrigation treatments, whereby the plants were irrigated to container capacity (control), 60% of the control (moderate deficit irrigation, MDI), or 40% of the control (severe deficit irrigation, SDI). Deficit irrigation was maintained for 2 months, and then all the plants were exposed to a recovery period of 112 month. Exposure to drought induced a decrease in shoot dry weight and leaf area and an increase in the root/shoot ratio. Height and plant width were significantly inhibited by the SDI, while flower color parameters were not affected by deficit treatment. The number of wilting and yellow leaves increased, coinciding with the increase in the number of inflorescences and open flowers. Deficit irrigation led to a leaf water potential of about -0.8MPa at midday, which could have caused an important decrease in stomatal conductance, affecting the photosynthetic rate (Pn). Chlorophyll fluorescence (Fvm) values of 0.80 in all treatments throughout the experiment demonstrate the lack of drought-induced damage to PSII photochemistry. Pressure-volume analysis revealed low osmotic adjustment values of 0.2MPa in the SDI treatment, accompanied by increases in the bulk tissue elastic modulus (epsilon, wall rigidity) and resulting in turgor loss at lower leaf water potential values (-1.38MPa compared with -1.0MPa for the control). Leaf water potential values throughout the experiment below those for Psitlp were not found at any sampling time. By the end of the recovery period, the leaf water potential, stomatal conductance and net photosynthesis had recovered. We infer from these results that moderate deficit irrigation in geranium reduced the consumption of water, while maintaining the good overall quality of plants. However, when SDI was applied, a reduction in the number of flowers per plant was observed.


Assuntos
Flores/fisiologia , Gases/metabolismo , Geranium/crescimento & desenvolvimento , Geranium/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Água/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Flores/efeitos dos fármacos , Geranium/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Pressão , Estações do Ano , Estresse Fisiológico/efeitos dos fármacos , Água/farmacologia
16.
J Plant Physiol ; 161(6): 675-82, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15266714

RESUMO

The influence of the arbuscular mycorrhizal fungus Glomus deserticola on the water relations, gas exchange parameters, and vegetative growth of Rosmarinus officinalis plants under water stress was studied. Plants were grown with and without the mycorrhizal fungus under glasshouse conditions and subjected to water stress by withholding irrigation water for 14 days. Along the experimental period, a significant effect of the fungus on the plant growth was observed, and under water stress, mycorrhizal plants showed an increase in aerial and root biomass compared to non-mycorrhizal plants. The decrease in the soil water potential generated a decrease in leaf water potential (psi(l)) and stem water potential (psi(x)) of mycorrhizal and non-mycorrhizal plants, with this decrease being lower in mycorrhizal water-stressed plants. Mycorrhization also had positive effects on the root hydraulic conductivity (Lp) of water stressed plants. Furthermore, mycorrhizal-stressed plants showed a more important decrease in osmotic potential at full turgor (psi(os)) than did non-mycorrhizal-stressed plants, indicating the capacity of osmotic adjustment. Mycorrhizal infection also improved photosynthetic activity (Pn) and stomatal conductance (g(s)) in plants under water stress compared to the non-mycorrhizal-stressed plants. A similar behaviour was observed in the photochemical efficiency of PSII (Fv/Fm) with this parameter being lower in non-mycorrhizal plants than in mycorrhizal plants under water stress conditions. In the same way, under water restriction, mycorrhizal plants showed higher values of chlorophyll content than did non-mycorrhizal plants. Thus, the results obtained indicated that the mycorrhizal symbiosis had a beneficial effect on the water status and growth of Rosmarinus officinalis plants under water-stress conditions.


Assuntos
Desastres , Fungos/patogenicidade , Gases/metabolismo , Rosmarinus/crescimento & desenvolvimento , Água/fisiologia , Biomassa , Clorofila/metabolismo , Fluorescência , Doenças das Plantas/microbiologia , Raízes de Plantas/fisiologia , Rosmarinus/microbiologia
17.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 28(7): 280-289, ago. 2001. ilus
Artigo em Es | IBECS | ID: ibc-21256

RESUMO

De transmisión autosómica, el síndrome de Meckel viene definido en su origen por una tríada malformativa que asocia encefalocele, displasia quística renal y polidactilia. De hecho, la extrema variabilidad de los casos clínicos publicados en la bibliografía pone de manifiesto que el polimorfismo de este síndrome constituye una característica esencial. La ecografía es, actualmente, el mejor medio de cribado prenatal de esta malformación letal. El cariotipo es indispensable para eliminar una trisomía 13 o 18. La frecuencia del gen del síndrome de Meckel en la población general es del orden de 1/400. Su aislamiento aportará una ayuda capital para el diagnóstico en razón de la multitud de síndromes polimalformativos que pueden evocarse ante el cuadro en el diagnóstico diferencial (AU)


Assuntos
Adulto , Feminino , Humanos , Feto/anormalidades , Polidactilia/complicações , Polidactilia/diagnóstico , Anormalidades Congênitas , Diagnóstico por Imagem/métodos , Índice de Apgar , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal/métodos , Computação em Informática Médica , Cariótipo XYY/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Aberrações Cromossômicas/diagnóstico , Aberrações Cromossômicas , Encefalocele/complicações , Encefalocele/diagnóstico , Sistema Nervoso Central/anormalidades , Sistema Nervoso Central/fisiopatologia , Trissomia/diagnóstico , Diagnóstico Diferencial
18.
Rev. méd. Urug ; 16(1): 14-7, mayo 2000. tab
Artigo em Espanhol | LILACS | ID: lil-275580

RESUMO

Con el objetivo de evaluar el aporte del estudio anátomo-patológico (AP) de la biopsia sinovial en las enfermedades reumáticas, se realizó un estudio prospectivo de dos años de duración. Se estudiaron en forma sistematizada todas las biopsias sinoviales remitidas desde el Instituto Nacional de Hematología del Uruguay (INRU) al departamento de Anatomía Patológica del Hospital de Clínicas. Estas fueron obtenidas por artroscopía solicitada como método diagnóstico o terapéutico por el médico tratante y procesadas de manera rutinaria. Se utilizó el test de t para su comparación. Se estudiaron 80 biopsias sinoviales. Los diagnósticos clínicos con los que fueron referidos los pacientes fueron: poliartritis reumatoide (PAR) en 23 casos, artrosis 7, artritis séptica 8, sin diagnóstico 31, otros diagnósticos 5. Con la biopsia se diagnosticaron 21 casos compatibles con PAR, con una concordancia de 54,3 por ciento, y 30,3 por ciento de sugerencia diagnóstica por la AP. El diagnóstico de artrosis se realizo en 11 casos con una concordancia de 85,7 por ciento y 45,5 por ciento de aporte AP. La concordancia entre diagnóstico y sospecha clínica de artritis séptica fue sólo de 25 por ciento, resultando 71,4 por ciento de los casos de diagnóstico AP exclusivo. Dos casos fueron artritis sépticas granulomatosas. En los casos sin diagnóstico la biopsia permitió aclararlo en 62,95 por ciento. Resultando 51,8 por ciento de pacientes con enfermedad de tratamiento conocido, 11,1 por ciento de biopsias dentro de límites normales, y 37,1 por ciento donde no aclaró el diagnóstico. Los parámetros microscópicos que mostraron diferencias estadísticamente significativas entre las diferentes enfermedades fueron el infiltrado pioleucocitario en las artritis sépticas, el infiltrado inflamatorio crónico linfoplasmocitario nodular y la necrosis fibrinoide en las biopsias compatibles con PAR y el tejido conjuntivo esclerohialinizado en las artrosis. No se reconocieron parámetros macroscópicos específicos de ninguna enfermedad, si bien se observó mayor frecuencia de vellosidades cortas y finas en las artrosis así como mayor cantidad de material floculento en el líquido sinovial en las artritis sépticas. Por lo tanto el estudio histopatológico de la sinovial permitió realizar un diagnóstico de entidad de 62,95 por ciento, permitiendo guiar la terapéutica así como evitar tratamientos innecesarios con toxicidad conocida en otros casos...


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Membrana Sinovial/patologia , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/patologia , Biópsia
19.
Phys Rev B Condens Matter ; 51(17): 11289-11295, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9977854
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