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2.
Sci Total Environ ; 795: 148792, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229238

RESUMO

Aquatic ecosystems are strongly body-size structured with a decline of numerical abundance with increasing body size (hereafter, the size spectrum). Marine and lake fish studies have reported consistent variations of size spectra in relation to environmental conditions and biotic composition, but little is known about stream fishes. Accordingly, in this study we test several hypotheses about the effects of local water conditions, biotic introductions and cumulative pressures (measured as the IMPRESS index) on the fish size-spectrum slope (that is, the linear rate of decline of fish abundance as body size increase in a log-log scale) and the size-spectrum intercept (commonly used as proxy for carrying capacity) among 118 local fish assemblages in streams of the NE Iberian Peninsula. To our knowledge, this is the first time that an extensive river fish dataset is used in a dendritic network to cover systematic changes of size-spectrum parameters. We find that the slope and intercept of the fish size spectrum are negatively correlated with nutrient concentration (mainly total phosphorus), with a greater relative abundance of small fishes but a decline of overall carrying capacity. Moreover, fish assemblages with greater relative abundance of non-native species have flatter size-spectrum slopes. In contrast, the IMPRESS index and climate-related variables are poor predictors of the shape of the fish size spectra. This study contributes to better understanding of the main factors structuring fish assemblages in lotic environments of the Iberian Peninsula. We encourage more research on this line to further explore the use of fish size structure to evaluate the ecological health of riverine ecosystems.


Assuntos
Ecossistema , Espécies Introduzidas , Animais , Peixes , Nutrientes , Rios
3.
Bull Exp Biol Med ; 170(5): 686-688, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33788114

RESUMO

The model of artificial intelligence DENTOMO, which allows automated deciphering the CT in maxillofacial area, was developed and implemented in practical dentistry. The presented model is based on two convolutional neural networks, includes a database and knowledge base, harmonized with SNOMED Clinical Terms is a systematically organized computer processable collection of medical terms providing codes, terms, synonyms and definitions used in clinical documentation and reporting. The developed model automatically decodes cone beam CT images, identifies and classifies the anatomical structures of the human dental system, and reveals the pathological processes and their dynamics in dentistry system. This model generates the medical reports automatically. Testing of DENTOMO model demonstrated a reasonable effectiveness in deciphering the CT of dental system. The developed technology allows computerizing and objectifying interpretation of CT of the dental system.


Assuntos
Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico , Humanos , Aprendizado de Máquina , Redes Neurais de Computação
4.
J Proteome Res ; 11(4): 2521-32, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22364559

RESUMO

Our understanding of the mechanisms by which nonalcoholic fatty liver disease (NAFLD) progresses from simple steatosis to steatohepatitis (NASH) is still very limited. Despite the growing number of studies linking the disease with altered serum metabolite levels, an obstacle to the development of metabolome-based NAFLD predictors has been the lack of large cohort data from biopsy-proven patients matched for key metabolic features such as obesity. We studied 467 biopsied individuals with normal liver histology (n=90) or diagnosed with NAFLD (steatosis, n=246; NASH, n=131), randomly divided into estimation (80% of all patients) and validation (20% of all patients) groups. Qualitative determinations of 540 serum metabolite variables were performed using ultraperformance liquid chromatography coupled to mass spectrometry (UPLC-MS). The metabolic profile was dependent on patient body-mass index (BMI), suggesting that the NAFLD pathogenesis mechanism may be quite different depending on an individual's level of obesity. A BMI-stratified multivariate model based on the NAFLD serum metabolic profile was used to separate patients with and without NASH. The area under the receiver operating characteristic curve was 0.87 in the estimation and 0.85 in the validation group. The cutoff (0.54) corresponding to maximum average diagnostic accuracy (0.82) predicted NASH with a sensitivity of 0.71 and a specificity of 0.92 (negative/positive predictive values=0.82/0.84). The present data, indicating that a BMI-dependent serum metabolic profile may be able to reliably distinguish NASH from steatosis patients, have significant implications for the development of NASH biomarkers and potential novel targets for therapeutic intervention.


Assuntos
Fígado Gorduroso/metabolismo , Obesidade/metabolismo , Adulto , Idoso , Área Sob a Curva , Biomarcadores/sangue , Biomarcadores/metabolismo , Índice de Massa Corporal , Progressão da Doença , Fígado Gorduroso/sangue , Feminino , Humanos , Masculino , Metaboloma , Pessoa de Meia-Idade , Análise Multivariada , Hepatopatia Gordurosa não Alcoólica , Obesidade/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Transplant Proc ; 40(10): 3810-2, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19100499

RESUMO

Although multifactorial anemia is common following orthotopic liver transplantation (OLT), the late introduction of sirolimus (SRL) has been associated with high rates of anemia, whose pathogenic mechanisms have not been fully studied. Herein we have described a case of severe anemia in an HIV+ OLT patient who was switched from calcineurin inhibitors (CNI) to SRL due to severe nephrotoxicity. After 22 weeks of SRL, hemoglobin levels dropped 4 g/dL to a nadir of 6.5 g/dL. After discarding other causes for anemia, we concluded that it displayed the features of anemia of a chronic inflammatory state (ACIS): decreased mean corpuscular volume (MCV), low serum iron despite high ferritinemia, and elevated fibrinogen and C-reactive protein (CRP) levels. SRL trough levels were never above the therapeutic range. After blood transfusions and erythropoietin (EPO) use, SRL was maintained within the lower range of therapeutic levels, with significant improvement in renal function. As described among kidney transplant recipients, SRL-related anemia in this HIV+ patient with CNI nephrotoxicity after OLT showed features of ACIS. Blood transfusions and EPO use allowed SRL maintenance.


Assuntos
Anemia/induzido quimicamente , Calcineurina/deficiência , Soropositividade para HIV , Imunossupressores/efeitos adversos , Transplante de Fígado/imunologia , Sirolimo/efeitos adversos , Proteínas Adaptadoras de Transdução de Sinal , Anemia/complicações , Anemia/terapia , Transfusão de Sangue , Proteína C-Reativa/metabolismo , Eritropoetina/uso terapêutico , Humanos , Inflamação/etiologia , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/complicações , Transferrina/metabolismo
6.
Vascul Pharmacol ; 47(2-3): 83-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17581795

RESUMO

BACKGROUND: The protective effect of acetylsalicylic acid (aspirin) against cardiovascular events is known to be weaker in women than in men. The present study was designed to test whether this effect of aspirin differed between sexes in an experimental model of diabetes with retinal ischemia. METHODS: We compared nondiabetic rats and rats after 1, 2 and 3 months of diabetes that were given 2 mg/kg/day p.o. of aspirin from the first day of diabetes. The variables recorded were platelet aggregation, production of thromboxane B(2) (TxB(2)), 6-keto-prostaglandin F(1alpha) and aortic nitric oxide, and the percentage of the retinal surface occupied by horseradish peroxidase (HRP)-permeable vessels. RESULTS: In female rats made diabetic, TxB(2) synthesis was more markedly reduced, and the percentage of HRP-permeable retinal vessels was less markedly reduced, than in their male counterparts. The response to aspirin treatment was weaker in female than in male diabetic rats in terms of inhibition of TxB(2) synthesis, increased nitric oxide production, and prevention of the increase in the percentage of retinal surface covered by HRP-permeable vessels. CONCLUSION: Aspirin was less effective in preventing retinal ischemia in experimental diabetes in female than in male rats.


Assuntos
Aspirina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Isquemia/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Vasos Retinianos/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/prevenção & controle , Feminino , Masculino , Óxido Nítrico/biossíntese , Agregação Plaquetária/efeitos dos fármacos , Prostaglandinas/biossíntese , Ratos , Ratos Wistar , Fatores Sexuais , Estreptozocina , Tromboxano B2/biossíntese
7.
Food Addit Contam ; 23(3): 305-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16517532

RESUMO

An analytical method for the determination of aflatoxin B1 in a tiger nut-based soft drinks named 'horchata' is described. The method is based on an immunoaffinity clean-up, followed by HPLC separation and fluorescence detection after electrochemical post-column derivatization. The detection limit (S/N = 3) and the quantification limit (S/N = 10) were 0.02 and 0.06 microg kg(-1), respectively. The mean recovery at a level of 2 microg l(-1) was 88% (n = 6) and the coefficient of variation was 9%. The method was applied to conduct a small market survey for a beverage named 'horchata' that is frequently consumed by parts of the population in Southern Europe. Twenty-two samples from Spanish and Belgian supermarkets were analysed. As a result, only one sample was found to contain aflatoxin B1 at the limit of quantitation of the method.


Assuntos
Aflatoxina B1/análise , Bebidas/análise , Cyperus/química , Contaminação de Alimentos/análise , Venenos/análise , Aflatoxina B1/toxicidade , Cromatografia Líquida de Alta Pressão/métodos , Inquéritos sobre Dietas , Venenos/toxicidade , Medição de Risco/métodos , Espanha
8.
Crit Rev Food Sci Nutr ; 44(3): 195-203, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15239373

RESUMO

An overview of liquid chromatographic methods, mainly employing fluorescence detection together with sample pre-treatment methods, is presented for the determination of the toxic group of fumonisin mycotoxins in various matrices.


Assuntos
Ração Animal/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Fumonisinas , Animais , Fumonisinas/análise , Fumonisinas/química , Humanos
9.
Arch Dis Child ; 88(12): 1128-30, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14670788

RESUMO

AIMS: To evaluate ibuprofen population pharmacokinetics in a large series of data collected in children with cystic fibrosis (CF) treated with high doses of ibuprofen (59 patients; 2-18 years), and to identify the main causes responsible for the considerable interindividual variability in ibuprofen serum levels. METHODS: Blood samples were collected during routine clinical care; serum ibuprofen concentrations were determined by HPLC. Fitting of the concentration/time data to a one compartment kinetic population model was performed by a non-linear mixed effect regression method. RESULTS: Body weight, dose, and ibuprofen dosage form (lysinate salt or the free acid form), for elimination clearance (CL/F); and body weight, dose, and fasting status for the apparent distribution volume (Vd/F) proved to be the covariates with influence in the model. The four factors identified helped to explain part of the interindividual variability observed, but the remaining unexplained variability made therapeutic drug monitoring absolutely essential.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Fibrose Cística/tratamento farmacológico , Ibuprofeno/farmacocinética , Administração Oral , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Disponibilidade Biológica , Peso Corporal , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Fibrose Cística/sangue , Jejum , Feminino , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/sangue , Masculino
10.
Ther Drug Monit ; 24(6): 742-5, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12451291

RESUMO

Digoxin pharmacokinetics were studied in a pediatric population with an age range of 6 days to 1 year using the population pharmacokinetic approach. Digoxin data were analyzed by mixed-effects modeling according to a one-compartment steady-state pharmacokinetic model using NONMEM software. The final model selected for the population prediction of digoxin clearance in pediatric patients was as follows: [equation: see text] Individual empirical Bayesian estimates were generated on the basis of the population estimates and were used to correlate the optimum dose of digoxin and patient age according to the following equation: [equation: see text] This equation and its derived nomogram may be used for the initial dosing of digoxin in children aged between 0 and 1 year. The use of this nomogram in routine monitoring requires further pharmacokinetic and clinical validation.


Assuntos
Cardiotônicos/farmacocinética , Digoxina/farmacocinética , Algoritmos , Teorema de Bayes , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Masculino , Modelos Biológicos , População , Estudos Retrospectivos , Software
11.
Naunyn Schmiedebergs Arch Pharmacol ; 365(2): 96-101, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11819026

RESUMO

The importance in experimental diabetic retinopathy of prostacyclin and nitric oxide (NO), as well as the possible effect of acetylsalicylic acid (ASA), are well known. To investigate the effect of two doses of aspirin in the prevention of retinal ischemia in streptozotocin-diabetic rats, we compared nondiabetic rats and diabetic rats after 1, 2 and 3 months of diabetes, and diabetic rats treated with 2 mg or 10 mg ASA/kg per day p.o. from the first day of diabetes. The parameters determined after 1, 2 and 3 months of development were platelet aggregation, thromboxane B(2) (TxB(2)) production, 6-keto-prostaglandin F(1)(alpha) (stable metabolite of prostacyclin), NO, plasma nitrites/nitrates, and percentage retinal surface occupied by horseradish peroxidase (HRP)-permeable vessels. In diabetic rats platelet aggregation and thromboxane concentration were increased, and prostacyclin, NO and area occupied by HRP-permeable vessels were decreased. Acetylsalicylic acid reduced platelet aggregation, and lowered thromboxane production by 82%-99%. Prostacyclin production was inhibited by 92%-95% with 10 mg ASA/kg per day, and by 8%-20% with 2 mg ASA/kg per day. In diabetic rats NO production increased after 2 and 3 months of treatment to levels seen in nondiabetic rats. The reduction in HRP-permeable retinal surface decreased from a maximum of 87% in DR to 51% after treatment with 2 mg ASA/kg per day, and to 62% after 10 mg ASA/kg per day. We conclude that ASA (2 mg/kg per day and 10 mg/kg per day) increased NO production in streptozotocin-diabetic rats and reduced the degree of retinal ischemia.


Assuntos
Aspirina/farmacologia , Diabetes Mellitus Experimental/sangue , Retinopatia Diabética/sangue , Óxido Nítrico/biossíntese , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Prostaglandinas/biossíntese , Vasos Retinianos/metabolismo , Administração Oral , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/etiologia , Retinopatia Diabética/prevenção & controle , Masculino , Nitratos/sangue , Nitritos/sangue , Ratos , Ratos Wistar , Vasos Retinianos/efeitos dos fármacos
12.
Br J Dermatol ; 133(1): 37-40, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7669638

RESUMO

Plasma levels of 8-methoxypsoralen (8-MOP) were determined by high-pressure liquid chromatography in 19 patients with psoriasis who were receiving bath-PUVA treatment, at different time points after the psoralen bath. The levels of 8-MOP varied between < 5 ng/ml (lower limit of detection) and 34 ng/ml, and we found a relationship between the plasma psoralen levels and the severity of the disease.


Assuntos
Banhos , Metoxaleno/sangue , Terapia PUVA , Fármacos Fotossensibilizantes/sangue , Psoríase/sangue , Psoríase/tratamento farmacológico , Administração Cutânea , Administração Oral , Ensaios Clínicos Controlados como Assunto , Humanos , Metoxaleno/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem , Psoríase/patologia , Índice de Gravidade de Doença
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