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1.
Alzheimers Dement ; 16(1): 60-70, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914226

RESUMO

INTRODUCTION: Behavioral variant frontotemporal dementia (bvFTD) may present sporadically or due to an autosomal dominant mutation. Characterization of both forms will improve understanding of the generalizability of assessments and treatments. METHODS: A total of 135 sporadic (s-bvFTD; mean age 63.3 years; 34% female) and 99 familial (f-bvFTD; mean age 59.9; 48% female) bvFTD participants were identified. f-bvFTD cases included 43 with known or presumed chromosome 9 open reading frame 72 (C9orf72) gene expansions, 28 with known or presumed microtubule-associated protein tau (MAPT) mutations, 14 with known progranulin (GRN) mutations, and 14 with a strong family history of FTD but no identified mutation. RESULTS: Participants with f-bvFTD were younger and had earlier age at onset. s-bvFTD had higher total Neuropsychiatric Inventory Questionnaire (NPI-Q) scores due to more frequent endorsement of depression and irritability. DISCUSSION: f-bvFTD and s-bvFTD cases are clinically similar, suggesting the generalizability of novel biomarkers, therapies, and clinical tools developed in either form to the other.


Assuntos
Demência Frontotemporal , Predisposição Genética para Doença , Mutação/genética , Testes Neuropsicológicos/estatística & dados numéricos , Fatores Etários , Idoso , Encéfalo/patologia , Proteína C9orf72/genética , Feminino , Demência Frontotemporal/classificação , Demência Frontotemporal/genética , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte , Progranulinas/genética , Proteínas tau/genética
2.
Nucleic Acids Res ; 44(1): 496-507, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26656950

RESUMO

Synthetic biology seeks to envision living cells as a matter of engineering. However, increasing evidence suggests that the genetic load imposed by the incorporation of synthetic devices in a living organism introduces a sort of unpredictability in the design process. As a result, individual part characterization is not enough to predict the behavior of designed circuits and thus, a costly trial-error process is eventually required. In this work, we provide a new theoretical framework for the predictive treatment of the genetic load. We mathematically and experimentally demonstrate that dependences among genes follow a quantitatively predictable behavior. Our theory predicts the observed reduction of the expression of a given synthetic gene when an extra genetic load is introduced in the circuit. The theory also explains that such dependence qualitatively differs when the extra load is added either by transcriptional or translational modifications. We finally show that the limitation of the cellular resources for gene expression leads to a mathematical formulation that converges to an expression analogous to the Ohm's law for electric circuits. Similitudes and divergences with this law are outlined. Our work provides a suitable framework with predictive character for the design process of complex genetic devices in synthetic biology.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Carga Genética , Biologia Sintética , Algoritmos , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Modelos Biológicos
3.
Amino Acids ; 34(2): 223-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17520329

RESUMO

We use a modeling and simulation approach to carry out an in silico analysis of the metabolic pathways involving arginine as a precursor of nitric oxide or polyamines in aorta endothelial cells. Our model predicts conditions of physiological steady state, as well as the response of the system to changes in the control parameter, external arginine concentration. Metabolic flux control analysis allowed us to predict the values of flux control coefficients for all the transporters and enzymes included in the model. This analysis fulfills the flux control coefficient summation theorem and shows that both the low affinity transporter and arginase share the control of the fluxes through these metabolic pathways.


Assuntos
Arginina/metabolismo , Células Endoteliais/metabolismo , Óxido Nítrico/biossíntese , Putrescina/biossíntese , Arginase/metabolismo , Transportador 1 de Aminoácidos Catiônicos/metabolismo , Transportador 2 de Aminoácidos Catiônicos/metabolismo , Simulação por Computador , Cinética , Redes e Vias Metabólicas
4.
Biochem Soc Trans ; 35(Pt 2): 381-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17371282

RESUMO

Evidence is growing in favour of a relationship between cancer and chronic inflammation, and particularly of the role of a polyamine and histamine metabolic interplay involved in these physiopathological problems, which are indeed highly complex biological systems. Decodification of the complex inter- and intra-cellular signalling mechanisms that control these effects is not an easy task, which must be helped by systems biology technologies, including new tools for location and integration of database-stored information and predictive mathematical models, as well as functional genomics and other experimental molecular approaches necessary for hypothesis validation. We review the state of the art and present our latest efforts in this area, focused on the amine metabolism field.


Assuntos
Aminas/metabolismo , Genômica , Animais , Comunicação Celular , Células Cultivadas , Endotélio Vascular/fisiologia , Histamina/metabolismo , Histidina Descarboxilase/metabolismo , Mamíferos , Mastócitos/fisiologia , Neoplasias/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
5.
Actas Esp Psiquiatr ; 33(1): 41-5, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15704030

RESUMO

INTRODUCTION: There are no conclusive data on the effectiveness of antidepressant drugs in the treatment of comorbid cases of alcohol dependence and depression. OBJECTIVES: To determine the effectiveness of venlafaxine on depression and on severity (need of treatment) of alcohol dependence and related problems. METHODS: Observational, open-label, multicenter, 24-week follow-up study. PATIENTS: 90 outpatients with diagnosis of alcohol dependence and associated major depression disorder (DSMIV criteria). OUTCOMES MEASURES: the Hamilton Rating Scale for Depression (HAM-D17), European Addiction Severity Index (EuropASI) and Clinical Global Impression, severity and improvement subscales, (CGI-S and CGI-I). Evaluations were performed at baseline and at weeks 2, 4, 8 and 24. RESULTS: Mean age 44.94+/-9.74 years; 73.3 % man. HAM-D17 mean scores significantly decreased from baseline (24.85+/-5.94) to week 24 (5.976+/-4.68) and at each of the follow-up visits vs previous visit (p < 0.0005). Significant decreases from baseline to week 24 were obtained in four areas of EuropASI: medical status (2.12+/-2.45 to 1.07+/-1.68), alcohol use (5.29+/-2.24 to 3.04+/-2.35), family/ social relationships (3.68+/-2.36 to 1.71+/-2.06) and psychiatric status (5.61+/-1.81 to 2.67+/-2.03). Tolerance was excellent or good in 76.7% of the patients. CONCLUSIONS: Venlafaxine demonstrated to be effective in the treatment of depressive alcoholic patients. Furthermore, it seems to be useful to decrease the severity of problems related with the alcohol use.


Assuntos
Alcoolismo/complicações , Alcoolismo/tratamento farmacológico , Antidepressivos de Segunda Geração/uso terapêutico , Cicloexanóis/uso terapêutico , Depressão/complicações , Depressão/tratamento farmacológico , Adulto , Feminino , Seguimentos , Humanos , Masculino , Cloridrato de Venlafaxina
6.
Cell Mol Life Sci ; 60(8): 1760-3, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14521154

RESUMO

(-)-epigallocatechin-3-gallate, an antiproliferative and antiangiogenic component of green tea, has been reported to inhibit dopa decarboxylase. In this report,we show that this compound also inhibits histidine decarboxylase, the enzymic activity responsible for histamine biosynthesis. This inhibition was proved by a double approach, activity measurements and UV-Vis spectra of enzyme-bound pyridoxal-5'-phosphate. At 0.1 mM (-)-epi-gallocatechin-3-gallate, histidine decarboxylase activity was inhibited by more than 60% and the typical spectrum of the internal aldimine form shifted to a stable major maximum at 345 nm, suggesting that the compound causes a stable change in the structure of the holoenzyme. Since histamine release is one of the primary events in many inflammatory responses, a new potential application of (-)-epigallocatechin-3-gallate in prevention or treatment of inflammatory processes is suggested by these data.


Assuntos
Catequina/análogos & derivados , Catequina/farmacologia , Inibidores Enzimáticos/farmacologia , Histidina Descarboxilase/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Catequina/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Histamina/biossíntese , Técnicas In Vitro , Ratos , Proteínas Recombinantes/antagonistas & inibidores , Chá/química , Células Tumorais Cultivadas
7.
Fresenius J Anal Chem ; 370(4): 393-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11495062

RESUMO

A new quartz crystal microbalance sensor is developed to determine formic acid at low concentrations. Four previously selected polymers with acid-base characteristics were tested as possible coatings. Polyoxyethylene bis [amine] presented the best results. The sensor is rapid, sensitive [0.67 Hz/(mg/m3)], and reversible at low concentrations. The detection limit for formic acid (7.2 mg/m3) is comparable with the short term exposure limit and the threshold limit values. It presents a fast mechanical response to pressure changes, so that it can be quickly used in different environments and situations. The sensor also shows a good stability in a temperature range typical of work atmospheres (16-36 degrees C). It has a wide linear range (7.2-911.2 mg/m3) and a long useful time. It is also applicable to other low molecular mass carboxylic acids such as acetic acid.


Assuntos
Formiatos/análise , Calibragem , Gases/análise , Indicadores e Reagentes , Polietilenoglicóis , Quartzo , Temperatura
8.
Anticancer Res ; 20(3A): 1691-4, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928093

RESUMO

BACKGROUND: Ehrlich ascites tumor is an experimental tumor model very suitable for performing comparative studies relating its growth in vitro and in vivo. We used this tumor model to study the potential modulatory effects of genistein and 2-methoxyestradiol, two anti-angiogenic compounds, on the proteolytic balance MMP/TIMP. Ehrlich cells grown in vitro secreted MMP-9, MMP-2 and two TIMPs; the treatment with either of the anti-angiogenic compounds here tested stimulated all these activities, but the increase in TIMPs activities of genistein-treated cells were higher than those of MMPs, thus inducing a decrease in the proteolytic balance. On the other hand, Ehrlich cells growing in vivo did not produce any detectable TIMP activity, but accumulated MMP-9 and MMP-2 during tumor growth. Both compounds induced significant decrease of MMPs activity when tumor cells were actively proliferating. It was concluded that both genistein and 2-methoxyestradiol could shift the proteolytic balance MMP/TIMP towards antiproteolysis in media or ascitic fluid conditioned by actively growing Ehrlich cells.


Assuntos
Carcinoma de Ehrlich/enzimologia , Inibidores Enzimáticos/farmacologia , Estradiol/análogos & derivados , Estradiol/farmacologia , Genisteína/farmacologia , Inibidores de Metaloproteinases de Matriz , Inibidores Teciduais de Metaloproteinases/metabolismo , 2-Metoxiestradiol , Animais , Líquido Ascítico/patologia , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/patologia , Adesão Celular/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Camundongos , Cavidade Peritoneal/patologia
9.
J Endod ; 26(10): 581-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11199797

RESUMO

The aim of the present study was to evaluate the influence of spreader shape on the quality of obturation. Forty-five single canal teeth with varying degrees of apical curvature were used throughout. The canals were prepared using the step-back technique and obturated with lateral condensation. The teeth were classified into three groups (A, B, and C) and treated as follows. Group A was treated with markedly conical, flat-ended spreaders (A to D; Dentsply-Maillefer, Ballaigues, Switzerland). Group B was treated with slightly conical (15 to 40) sharp-pointed CC-cord spreaders. Group C was treated with CC-cord, slightly conical but flat-ended spreaders. The obturated teeth were decalcified in 7.5% nitric acid to obtain four cross-sections: the first at 2 mm from the apex and then the following three sections at 1-mm intervals. Section thickness was approximately 1 mm. Each section was photographed under a stereoscopic microscope. The following areas were measured on each of the microphotographs using a planimeter: (a) gutta-percha mass, (b) mass of sealer, (c) foreign bodies, and (d) empty spaces. These four areas were added to determine total cross-sectional canal area and then the percent of that area attributable to a and to b + c + d was calculated. The statistical analysis of the data (parametric Student's t test for independent groups) revealed that only in group B was the area occupied by a, the gutta-percha mass, significantly greater at all levels than the area occupied by b + c + d. Next in obturation effectiveness was group C, followed by group A.


Assuntos
Colagem Dentária/normas , Cavidade Pulpar/anatomia & histologia , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/instrumentação , Técnica de Descalcificação , Cavidade Pulpar/diagnóstico por imagem , Desenho de Equipamento , Corpos Estranhos/classificação , Guta-Percha/química , Humanos , Fotografação , Radiografia , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Aço Inoxidável , Estatística como Assunto , Propriedades de Superfície , Ápice Dentário/anatomia & histologia , Cimento de Óxido de Zinco e Eugenol/química
17.
Minerva Med ; 67(6): 406-10, 1976 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-1250533

RESUMO

After mentioning the close relationships between enviornmental pollution and the respiratory system, the various polluting compounds, from solid particles to fumes and gases, are reviewed, special attention being paid to the commonest types (sulphur and nitrogen compounds). Attention is called to two other polluting factors, asbestos and radioactivity, both of which are important in neoplastic pathology. The complexity of the air pollution problem in relation to respiratory pathology is stressed while stating that the most important problem remains that of prevention.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Doenças Respiratórias/etiologia , Neoplasias do Sistema Respiratório/etiologia , Poluentes Radioativos do Ar/efeitos adversos , Humanos
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