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1.
Plant Cell Physiol ; 53(9): 1607-16, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22833666

RESUMO

Nitrate reductase (NR) activity is necessary for the synthesis of nitric oxide (NO), a key signaling molecule in plants. Here, we investigated the effect of NR deficiency on NO production and phenylpropanoid metabolism of Arabidopsis thaliana leaves. HPLC-mass spectrometry analysis showed that the NR double mutant (nia1 nia2) is deficient in the synthesis of sinapoylmalate (SM), the main phenylpropanoid end-product in wild-type leaves, resulting in accumulation of its precursor sinapoylglucose (SG). While real-time PCR analysis revealed no significant difference at the transcript level, sinapoylglucose:malate sinapoyltransferase (SMT) activity in leaf extracts was reduced in the mutant compared with the wild type. The low levels of SM in nia1 nia2 leaves do not result from the deficient nitrogen incorporation into amino acids, since the recovery of the amino acid content of nia1 nia2 by irrigating the plants with glutamine did not change the metabolic profile of this mutant. In contrast, an increased supply of nitrate stimulated NR activity and NO production, and enhanced SM and decreased SG levels in both genotypes. Nevertheless, sinapic acid esters in nia1 nia2 were not recovered when compared with those detected in the leaves of the wild-type plant. Mutant plants grown in medium supplemented with malate and an NO donor recovered SM to the levels of wild-type leaves. Overall, the results suggest that SMT activity is dependent on the NR-dependent steady-state levels of NO during plant development.


Assuntos
Aciltransferases/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Nitrato Redutase/metabolismo , Óxido Nítrico/metabolismo , Folhas de Planta/enzimologia , Arabidopsis/efeitos dos fármacos , Biocatálise/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cinamatos/metabolismo , Ácidos Cumáricos/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ésteres/metabolismo , Glucosídeos/metabolismo , Malatos/metabolismo , Malatos/farmacologia , Mutação/genética , Nitratos/metabolismo , Óxido Nítrico/farmacologia , Fenilpropionatos/metabolismo , Folhas de Planta/efeitos dos fármacos
2.
IEEE Trans Pattern Anal Mach Intell ; 44(9): 4807-4818, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33735073

RESUMO

This manuscript presents the design of a deep differential neural network (DDNN) for pattern classification. First, we proposed a DDNN topology with three layers, whose learning laws are derived from a Lyapunov analysis, justifying local asymptotic convergence of the classification error and the weights of the DDNN. Then, an extension to include an arbitrary number of hidden layers in the DDNN is analyzed. The learning laws for this general form of the DDNN offer a contribution to the deep learning framework for signal classification with biological nature and dynamic structures. The DDNN is used to classify electroencephalographic signals from volunteers that perform an identification graphical test. The classification results show exponential growth in the signal classification accuracy from 82 percent with one layer to 100 percent with three hidden layers. Working with DDNN instead of static deep neural networks (SDNN) represents a set of advantages, such as processing time and training period reduction up to almost 100 times, and the increment of the classification accuracy while working with less hidden layers than working with SDNN, which are highly dependent on their topology and the number of neurons in each layer. The DDNN employed fewer neurons due to the induced feedback characteristic.


Assuntos
Aprendizado Profundo , Algoritmos , Humanos , Redes Neurais de Computação
3.
Rev Gastroenterol Mex (Engl Ed) ; 87(4): 455-461, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35523684

RESUMO

INTRODUCTION AND AIM: Chronic hepatitis C is one of the main causes of cirrhosis of the liver. Treatment with direct-acting antivirals (DAAs) improves survival. There is controversy as to whether AADs create an increased risk for the development of hepatocellular carcinoma (HCC). The aim of the present study was to determine the risk factors for developing HCC in patients with chronic hepatitis C treated with DAAs. MATERIALS AND METHODS: A cohort study was conducted, within the time frame of June 2017 and June 2018, on patients >18 years of age, with chronic hepatitis C, genotypes 1 and 4, with one year of follow-up, to evaluate the presence of HCC. RESULTS: We analyzed 108 patients, 71 (65%) of whom were women. Mean patient age was 56.24 years (±10.6), 1b was the most frequent genotype (63%), and 49% of the patients received treatment with DAAs (ombitasvir/paritaprevir/ritonavir plus dasabuvir). Thirty-four (31%) patients were obese. Fifty-three percent (58) had cirrhosis and 82% (89) had Child-Pugh class A liver function. Sustained virologic response at 12 weeks was 100%. Eight (7%) patients developed HCC and 1b was the most frequently associated genotype (87%). The presence of regenerative nodules >10 mm (P < .05), esophageal varices (P < .05), cirrhosis of the liver (P < .05), Child-Pugh B-C (P < .05), and alpha-fetoprotein >20 IU/mL (P = 0.20) one year after treatment were associated with the development of HCC. CONCLUSIONS: The risk factors for developing HCC were the presence of cirrhosis of the liver, Child-Pugh class B liver function, esophageal and/or gastric varices, and genotype 1b.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Neoplasias Hepáticas , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Neoplasias Hepáticas/complicações , Hepacivirus/genética , Estudos de Coortes , Cirrose Hepática/complicações , Fatores de Risco
4.
Water Res ; 182: 116033, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32721702

RESUMO

The removal efficiency of nine pharmaceutical compounds from primary sludge was evaluated in two different operating conditions: (i) in conventional Mesophilic Anaerobic Digestion (MAD) alone and (ii) in a co-treatment process combining Mesophilic Anaerobic Digestion and a Thermophilic Aerobic Reactor (MAD-TAR). The pilot scale reactors were fed with primary sludge obtained after decantation of urban wastewater. Concerning the biodegradation of organic matter, thermophilic aeration increased solubilization and hydrolysis yields of digestion, resulting in a further 26% supplementary removal of chemical oxygen demand (COD) in MAD-TAR process compared to the conventional mesophilic anaerobic digestion. The highest removal rate of target micropollutants were observed for caffeine (CAF) and sulfamethoxazole (SMX) (>89%) with no substantial differences between both processes. Furthermore, MAD-TAR process showed a significant increase of removal efficiency for oxazepam (OXA) (73%), propranolol (PRO) (61%) and ofloxacine (OFL) (41%) and a slight increase for diclofenac (DIC) (4%) and 2 hydroxy-ibuprofen (2OH-IBP) (5%). However, ibuprofen (IBP) and carbamazepine (CBZ) were not degraded during both processes. Anaerobic digestion affected the liquid-solid partition of most target compounds. Sorbed fraction of pharmaceutical compounds on the sludge tend to decrease after digestion, this tendency being more pronounced in the case of the MAD-TAR process due to much lower concentration of solids.


Assuntos
Preparações Farmacêuticas , Eliminação de Resíduos Líquidos , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Esgotos/análise , Temperatura
5.
Med Biol Eng Comput ; 57(9): 1843-1860, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31209711

RESUMO

This article shows the design of a robust second-order sliding mode controller to solve the trajectory tracking problem of an active orthosis for assisting back physiotherapies. The orthosis was designed in agreement with morphological dimensions and its articulations distribution followed the same designing rules. The orthosis has six articulated arms attached to an articulated column. The orthosis was fully instrumented with actuators and position sensors at each articulation. The controller implemented a class of hybrid/position controller depending on the relative force exerted by the patient and the orthosis movement. The position information provided by each articulation was supplied to a distributed super-twisting differentiator to recover the corresponding angular velocity. A set of twisting controllers was implemented to regulate the position of the robot in agreement to predefined reference trajectories. Reference trajectories were obtained from a biomechanical-based analysis. The hybrid tracking control problem solved the automation of the assisted therapy to the patient, including the force feedback. The performance of the orthosis was tested with different dummy bodies with different resistance. The robust output feedback controller successfully tracked the reference trajectories despite the material of the dummy used during the testing. The orthosis was evaluated with two volunteers using a simple reference trajectory. Graphical Abstract General structure of the active back assisted orthosis.


Assuntos
Aparelhos Ortopédicos , Modalidades de Fisioterapia/instrumentação , Medula Espinal/fisiopatologia , Simulação por Computador , Desenho de Equipamento , Retroalimentação , Humanos , Modelos Teóricos , Robótica/instrumentação , Robótica/métodos , Software , Medula Espinal/fisiologia
7.
Plant Cell Physiol ; 49(7): 1112-21, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18540030

RESUMO

The nitrate reductase (NR)-defective double mutant of Arabidopsis thaliana (nia1 nia2) has previously been shown to present a low endogenous content of NO in its leaves compared with the wild-type plants. In the present study, we analyzed the effect of NR mutation on floral induction and development of A. thaliana, as NO was recently described as one of the signals involved in the flowering process. The NO fluorescent probes diaminofluorescein-2 diacetate (DAF-2DA) and 1,2-diaminoanthraquinone (1,2-DAA) were used to localize NO production in situ by fluorescence microscopy in the floral structures of A. thaliana during floral development. Data were validated by incubating the intact tissues with DAF-2 and quantifying the DAF-2 triazole by fluorescence spectrometry. The results showed that NO is synthesized in specific cells and tissues in the floral structure and its production increases with floral development until anthesis. In the gynoecium, NO synthesis occurs only in differentiated stigmatic papillae of the floral bud, and, in the stamen, only anthers that are producing pollen grains synthesize NO. Sepals and petals do not show NO production. NR-deficient plants emitted less NO, although they showed the same pattern of NO emission in their floral organs. This mutant blossomed precociously when compared with wild-type plants, as measured by the increased caulinar/rosette leaf number and the decrease in the number of days to bolting and anthesis, and this phenotype seems to result from the markedly reduced NO levels in roots and leaves during vegetative growth. Overall, the results reveal a role for NR in the flowering process.


Assuntos
Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Flores/enzimologia , Flores/crescimento & desenvolvimento , Nitrato Redutase/deficiência , Óxido Nítrico/biossíntese , Antraquinonas/metabolismo , Fluoresceína/metabolismo , Mutação/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo
8.
Transplant Proc ; 40(9): 3261-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010248

RESUMO

UNLABELLED: Human parvovirus B19 (PVB19) is the etiologic agent of erythema infectiosum (fifth disease), a common childhood exanthema. Immunocompromised patients risk developing chronic infections leading to pure red blood cell aplasia. Herein we have reported our experience with two pediatric renal transplant recipients who had severe pure red cell aplasia in the early period after surgery, accompanying PVB19 infection. FIRST CASE: A 6-year-old boy underwent pro emptive living-related renal transplantation in September 2006. On day 4, he developed abdominal discomfort and diarrhea. After transplantation, he began an asymptomatic drop in hematocrit without reticulocytosis, which was unresponsive to recombinant erythropoietin. Diarrhea also persisted. Polymerase chain reaction (PCR) was positive for cytomegalovirus (CMV) in the gastrointestinal tract. PVB19 was confirmed by PCR on a bone marrow sample. He was transfused with packed red cells and treated with ganciclovir and intravenous immunoglobulin (IVIG). His hematocrit increased and diarrhea ended. Six months later anemia recurred requiring a second infusion of IVIG. Subsequently he has done well. SECOND CASE: A 15-year-old boy received a living-related renal transplant in October 2006, after 2 years on automated peritoneal dialysis. One month later he developed a progressive, nonregenerative anemia. A bone marrow aspirate confirmed a PVB19 infection by PCR. He received a blood transfusion and IVIG with a favorable response. CONCLUSIONS: The presence of persistent anemia in immunocompromised hosts with a low reticulocyte count suggests PVB19 infection. IVIG therapy is effective to treat chronic PVB19 infections.


Assuntos
Anemia/etiologia , Ganciclovir/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Transplante de Rim/efeitos adversos , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/tratamento farmacológico , Parvovirus B19 Humano , Adolescente , Antivirais/uso terapêutico , Criança , Creatinina/sangue , Hematócrito , Humanos , Masculino , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/isolamento & purificação , Reação em Cadeia da Polimerase
9.
ISA Trans ; 64: 47-55, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27476801

RESUMO

Most of the research in sliding mode theory has been carried out to in continuous time to solve the estimation and control problems. However, in discrete time, the results in high order sliding modes have been less developed. In this paper, a discrete time super-twisting-like algorithm (DSTA) was proposed to solve the problems of control and state estimation. The stability proof was developed in terms of the discrete time Lyapunov approach and the linear matrix inequalities theory. The system trajectories were ultimately bounded inside a small region dependent on the sampling period. Simulation results tested the DSTA. The DSTA was applied as a controller for a Furuta pendulum and for a DC motor supplied by a DSTA signal differentiator.

10.
Can J Vet Res ; 69(1): 46-52, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15745222

RESUMO

Mammalian skeletal muscle expresses splice variants of neuronal nitric oxide synthase (nNOS). Skeletal muscles have a metabolically heterogeneous population of myofibers, and fiber composition in equine skeletal muscle is correlated with athletic ability in endurance events. In this study, we investigated whether nNOS expression in equine skeletal muscle is related to fiber type and endurance training. Biopsy samples obtained from the gluteus medius of sedentary- (SH) and endurance-trained (TH) horses were examined for the electrophoretic mobility of myosin heavy chain (MHC) and NOS activity. Serial tissue cross-sections were stained for myosin ATPase and nicotinamide adenine dinucleotide (NADH) reductase, and also immunostained for nNOS. The gluteus medius of TH had higher levels of nNOS expression and activity when compared to muscle from SH. In SH, nNOS was restricted to the subsarcolemmal area while in TH nNOS was also present at cytoplasmic sites. A splice variant of nNOS was heterogeneously distributed among the different myofibers, its expression being higher in fast-oxidative-glycolytic type IIA fibers than in fast-glycolytic type IIX fibers and absent in slow-twitch type I fibers. Trained horses had a significantly higher relative content of type IIA fibers, a greater oxidative capacity, and a lower percentage of type IIX fibers when compared with SH. The differences in muscle fiber typing between the 2 groups of horses reflected alterations that probably resulted from the endurance-training program. Overall, these results show that nNOS is differentially expressed and localized in the gluteus medius according to the fiber type and the athletic conditioning of the horses.


Assuntos
Cavalos/fisiologia , Fibras Musculares Esqueléticas/enzimologia , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Nádegas , Estudos de Casos e Controles , Feminino , Cavalos/metabolismo , Imuno-Histoquímica/veterinária , Masculino , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/anatomia & histologia , Cadeias Pesadas de Miosina/análise , Resistência Física/fisiologia
12.
Rev Med Chil ; 120(1): 36-42, 1992 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-1305308

RESUMO

The clinical, surgical and histopathologic characteristics of patients with gastric cancer were compared among 3 consecutive periods from 1958 to 1990. A significant increase in the frequency of location at the upper third of the stomach, a greater proportion of resectable lesions, an increasing tendency towards extended total gastrectomy and a significant increase in the frequency of undifferentiated or diffuse carcinoma were observed. A change in pathogenetic factors along the years may be involved in the differences described.


Assuntos
Neoplasias Gástricas , Adulto , Fatores Etários , Idoso , Análise de Variância , Chile/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Fatores de Tempo
13.
Rev. chil. neuro-psiquiatr ; 21(3): 234-42, 1983.
Artigo em Espanhol | LILACS | ID: lil-17719

RESUMO

Se presentan 4 pacientes con sindromes amnesicos: un caso postencefalitico, un caso de amnesia global transitoria, un ictus amnesico y un sindrome de Korsakoff nutricio-alcoholico. Se senala la asociacion entre la nocion de enfermedad y la ausencia de fabulaciones en las amnesias hipocampicas (postencefaliticas, ammnesia global transitoria y el ictus amnesico) y entre la anosognosia y la presencia de fabulaciones en el sindrome de Korsakoff nutricio-alcoholico, en que existen lesiones de cuerpos mamilares y de nucleos dorsomediales del talamo. Se senala que la relacion funcional entre anosognosia y fabulaciones tambien puede observarse en otros defectos neurologicos


Assuntos
Adulto , Humanos , Masculino , Transtorno Amnésico Alcoólico , Amnésia , Encefalite , Hipocampo
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