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1.
Mater Horiz ; 10(12): 5796-5804, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37815428

RESUMO

The industrial adoption of low-carbon technologies and renewable electricity requires novel tools for electrifying unitary steps and efficient energy storage, such as the catalytic synthesis of valuable chemical carriers. The recently-discovered use of microwaves as an effective reducing agent of solid materials provides a novel framework to improve this chemical-conversion route, thanks to promoting oxygen-vacancy formation and O2-surface exchange at low temperatures. However, many efforts are still required to boost the redox properties and process efficiency. Here, we scrutinise the dynamics and the physicochemical dependencies governing microwave-induced redox transformations on solid-state ion-conducting materials. The reduction is triggered upon a material-dependent induction temperature, leading to a characteristically abrupt rise in electric conductivity. This work reveals that the released O2 yield strongly depends on the material's composition and can be tuned by controlling the gas-environment composition and the intensity of the microwave power. The reduction effect prevails at the grain surface level and, thus, amplifies for fine-grained materials, and this is ascribed to limitations in oxygen-vacancy diffusion across the grain compared to a microwave-enhanced surface evacuation. The precise cyclability and stability of the redox process will enable multiple applications like gas depuration, energy storage, or hydrogen generation in several industrial applications.

2.
Allergol. immunopatol ; 48(6): 568-575, nov.-dic. 2020. graf, tab
Artigo em Inglês | IBECS | ID: ibc-199244

RESUMO

INTRODUCTION AND OBJECTIVES: The diagnosis of IgE-mediated cow's milk allergy (CMA) is often based on clinical history and on specific IgE levels and/or skin-prick tests (SPT), both of which are sensitive but not specific. The gold standard, oral food challenge (OFC), is expensive and time-consuming and involves a risk of severe allergic reactions. This study aimed to determine the value of specific IgEs, ratios of specific IgEs for cow's milk and its components to total IgE, and wheal size on SPT for predicting a positive OFC for CMA. MATERIAL AND METHODS: We retrospectively studied 72 patients [median age, four years; age range 0.75-15 years] sensitized to cow's milk who underwent OFCs to milk. predictive variables between patients with positive and negative OFCs were compared. Receiver operator characteristic (ROC) curves were uses to assess variables' discriminatory capacity and Youden's index to determine the best cut-offs for predicting CMA. RESULTS: The OFC was positive in 39 (54%) patients. Wheal size on SPT and all specific IgEs and specific-to-total IgE ratios were significantly different between patients with positive OFCs and those with negative OFCs (p < 0.001). The variable with the greatest area under the ROC curve was casein-specific IgE (0.98), followed by β-lactoglobulin-specific IgE (0.923), casein-specific-to-total-IgE ratio (0.919), and α-lactalbumin-specific IgE (0.908). Casein-specific IgE ≥ 0.95kU/L yielded 88.9% sensitivity and 90.9% specificity. CONCLUSIONS: In our center, casein-specific IgE > 0.95kU/L can obviate an OFC to cow's milk for the diagnosis of CMA in patients sensitized to cow's milk with a compatible history


No disponible


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Hipersensibilidade a Leite/diagnóstico , Substitutos do Leite Humano , Imunoglobulina E/sangue , Estudos Retrospectivos , Hipersensibilidade a Leite/imunologia , Padrões de Referência , Caseínas/sangue , Caseínas/imunologia , Lactalbumina/sangue , Lactalbumina/imunologia , Curva ROC , Estatísticas não Paramétricas , Valores de Referência , Valor Preditivo dos Testes , Testes de Irritação da Pele
3.
Allergol Immunopathol (Madr) ; 48(6): 568-575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32402626

RESUMO

INTRODUCTION AND OBJECTIVES: The diagnosis of IgE-mediated cow's milk allergy (CMA) is often based on clinical history and on specific IgE levels and/or skin-prick tests (SPT), both of which are sensitive but not specific. The gold standard, oral food challenge (OFC), is expensive and time-consuming and involves a risk of severe allergic reactions. This study aimed to determine the value of specific IgEs, ratios of specific IgEs for cow's milk and its components to total IgE, and wheal size on SPT for predicting a positive OFC for CMA. MATERIAL AND METHODS: We retrospectively studied 72 patients [median age, four years; age range 0.75-15 years] sensitized to cow's milk who underwent OFCs to milk. predictive variables between patients with positive and negative OFCs were compared. Receiver operator characteristic (ROC) curves were uses to assess variables' discriminatory capacity and Youden's index to determine the best cut-offs for predicting CMA. RESULTS: The OFC was positive in 39 (54%) patients. Wheal size on SPT and all specific IgEs and specific-to-total IgE ratios were significantly different between patients with positive OFCs and those with negative OFCs (p<0.001). The variable with the greatest area under the ROC curve was casein-specific IgE (0.98), followed by ß-lactoglobulin-specific IgE (0.923), casein-specific-to-total-IgE ratio (0.919), and α-lactalbumin-specific IgE (0.908). Casein-specific IgE ≥0.95kU/L yielded 88.9% sensitivity and 90.9% specificity. CONCLUSIONS: In our center, casein-specific IgE >0.95kU/L can obviate an OFC to cow's milk for the diagnosis of CMA in patients sensitized to cow's milk with a compatible history.


Assuntos
Alérgenos/administração & dosagem , Imunoglobulina E/sangue , Hipersensibilidade a Leite/diagnóstico , Proteínas do Leite/administração & dosagem , Administração Oral , Adolescente , Alérgenos/imunologia , Animais , Bovinos , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/imunologia , Lactente , Masculino , Hipersensibilidade a Leite/sangue , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/imunologia , Curva ROC , Valores de Referência , Estudos Retrospectivos
4.
Alcohol Alcohol ; 55(2): 157-163, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-31897468

RESUMO

AIMS: Platelet-derived growth factor (PDGF) promotes liver collagen deposition, acting on hepatic stellate cells. Despite this, low serum PDGF levels were reported in chronic hepatitis C or B infection, although some studies yield the opposite result. Since PDGF may be related not only to fibrosis but also with vascular, neuronal or muscle disease, it is important to analyze its behavior in alcoholics. METHODS: In total, 17 controls and 62 alcoholic patients consecutively admitted to the hospitalization unit of the Internal Medicine Service were included. We determined serum levels of PDGF C, routine laboratory evaluation, tumor necrosis factor-α, interleukin (IL)-6 and IL-8 and malondialdehyde (MDA) levels. We analyzed the relationships between PDGF and liver function, ethanol intake and inflammatory reaction by both univariate and multivariate analysis to discern which variables PDGF levels depend on. RESULTS: Serum PDGF levels were significantly lower among patients (675 ± 466 pg/ml) than among controls (1074 ± 337 pg/ml; Z = 3.70; P < 0.001), and even lower among cirrhotics (549 ± 412 among cirrhotics vs 778 ± 487 among non-cirrhotics; Z = 2.33; P = 0.02). PDGF levels showed a direct correlation with prothrombin activity (ρ = 0.50; P < 0.001), platelet count (ρ = 0.44; P < 0.001) and inverse ones with bilirubin (ρ = -0.39; P = 0.002), IL-6 (ρ = -0.33; P = 0.016), IL-8 (ρ = -0.47; P < 0.001), and MDA levels (ρ = -0.44; P < 0.001). By multivariate analysis, only prothrombin activity and platelet count were independently related to PDGF. CONCLUSION: PDGF-C levels are decreased in alcoholics, especially among cirrhotics. Multivariate analysis discloses that only prothrombin activity and platelet count are independently related to PDGF-C levels.


Assuntos
Alcoolismo/sangue , Linfocinas/sangue , Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/complicações , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Cirrose Hepática Alcoólica/sangue , Cirrose Hepática Alcoólica/complicações , Testes de Função Hepática , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas , Fator de Necrose Tumoral alfa/sangue
5.
An. pediatr. (2003. Ed. impr.) ; 84(1): e1-e9, ene. 2016. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-147634

RESUMO

La displasia broncopulmonar (DBP) es la secuela más prevalente del recién nacido pretérmino, y sigue suponiendo un motivo frecuente de consulta en las unidades de Neumología Pediátrica. La decisión del alta de la unidad neonatal debe apoyarse en una valoración exhaustiva de la situación clínica del paciente y en el cumplimiento de unos requisitos, que incluyen la estabilidad respiratoria y nutricional, y la instrucción a los cuidadores en el manejo domiciliario. Para un control adecuado de la enfermedad, es necesario que quede establecido, previamente al alta, un calendario de visitas y de exploraciones complementarias, y deben aplicarse las pautas de prevención de exacerbaciones y el tratamiento apropiados. El concepto de DBP como enfermedad multisistémica es fundamental en el seguimiento de los pacientes y debe ser tenido en cuenta para un buen control de la enfermedad. En este documento, el Grupo de Trabajo de Patología Respiratoria Perinatal de la Sociedad Española de Neumología Pediátrica propone un protocolo que sirva como referencia para unificar el seguimiento de los pacientes con DBP entre los diferentes centros y ámbitos asistenciales. Se revisan los aspectos a tener en cuenta en la evaluación previa al alta de la Unidad Neonatal y las principales complicaciones durante el seguimiento. Seguidamente, se detallan las recomendaciones en materia de tratamiento de la enfermedad y prevención de complicaciones, los controles tras el alta y su cronología


Bronchopulmonary dysplasia (BPD) is the most common complication of preterm birth, and remains a major problem in pediatric pulmonology units. The decision of discharging from the Neonatal Unit should be based on a thorough assessment of the condition of the patient and compliance with certain requirements, including respiratory and nutritional stability, and caregiver education on disease management. For proper control of the disease, a schedule of visits and complementary tests should be established prior to discharge, and guidelines for prevention of exacerbations and appropriate treatment should be applied. In this paper, the Working Group in Perinatal Respiratory Diseases of the Spanish Society of Pediatric Pulmonology proposes a protocol to serve as a reference for the follow up of patients with BPD among different centers and health care settings. Key factors to consider when planning discharge from the Neonatal Unit and during follow up are reviewed. Recommendations on treatment and prevention of complications are then discussed. The final section of this guide aims to provide a specific schedule for follow-up and diagnostic interventions to be performed in patients with BPD


Assuntos
Humanos , Masculino , Feminino , Criança , Displasia Broncopulmonar/epidemiologia , Displasia Broncopulmonar/prevenção & controle , Protocolos Clínicos , Recém-Nascido de muito Baixo Peso , Doenças do Prematuro/diagnóstico , Gasometria/métodos , Displasia Broncopulmonar/complicações , Displasia Broncopulmonar/diagnóstico , Displasia Broncopulmonar/fisiopatologia , Seguimentos , Recém-Nascido Prematuro/fisiologia , Indicadores Básicos de Saúde
6.
Eur J Vasc Endovasc Surg ; 51(2): 268-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26520178

RESUMO

OBJECTIVES: The study aim was to confirm the factorial structure of the short (14 item) version of the ChronIc Venous Insufficiency quality of life Questionnaire (CIVIQ-14) using the Vein Consult Program (VCP) results. METHODS: The international VCP study sought to evaluate the impact of chronic venous disease (CVD) on health care costs and quality of life (QoL). The factorial structure of the CIVIQ-14 was evaluated using two methods: exploratory factor analysis (EFA) to calculate the probabilities of items and dimensions remaining stable and to study the dimensionality of the scale using explained variance criteria, followed by confirmatory factor analysis (CFA) to confirm the original three dimensional structure and investigate alternative models that may have arisen from the dimensionality analysis. We also used the VCP results to evaluate the psychometric properties of the questionnaire and conducted subgroup analyses on countries with validated translations. RESULTS: A total of 47,149 questionnaires from 17 countries were available in the VCP. EFA revealed both items and dimensions as 100% stable. Dimensionality analysis showed that a two factor approach could be considered. CFA revealed the CIVIQ-14 three dimensional structure to be acceptable while rejecting the two dimensional model. Psychometric analysis confirmed the construct validity, internal consistency, and known groups validity of the CIVIQ-14. The results of subgroup analyses were consistent with those of the primary analysis. CONCLUSIONS: CFA of VCP data supported the factorial structure of the CIVIQ-14. The analysis corroborates the wide use of CIVIQ-14 as a valid instrument for reporting QoL in CVD patients.


Assuntos
Psicometria , Qualidade de Vida , Inquéritos e Questionários , Insuficiência Venosa/diagnóstico , Insuficiência Venosa/psicologia , Atividades Cotidianas , Doença Crônica , Efeitos Psicossociais da Doença , Europa (Continente) , Análise Fatorial , Humanos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Insuficiência Venosa/fisiopatologia
7.
An Pediatr (Barc) ; 84(1): 61.e1-9, 2016 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-26089228

RESUMO

Bronchopulmonary dysplasia (BPD) is the most common complication of preterm birth, and remains a major problem in pediatric pulmonology units. The decision of discharging from the Neonatal Unit should be based on a thorough assessment of the condition of the patient and compliance with certain requirements, including respiratory and nutritional stability, and caregiver education on disease management. For proper control of the disease, a schedule of visits and complementary tests should be established prior to discharge, and guidelines for prevention of exacerbations and appropriate treatment should be applied. In this paper, the Working Group in Perinatal Respiratory Diseases of the Spanish Society of Pediatric Pulmonology proposes a protocol to serve as a reference for the follow up of patients with BPD among different centers and health care settings. Key factors to consider when planning discharge from the Neonatal Unit and during follow up are reviewed. Recommendations on treatment and prevention of complications are then discussed. The final section of this guide aims to provide a specific schedule for follow-up and diagnostic interventions to be performed in patients with BPD.


Assuntos
Displasia Broncopulmonar/diagnóstico , Seguimentos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Guias de Prática Clínica como Assunto
8.
Allergol. immunopatol ; 43(5): 507-526, sept.-oct. 2015. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-141114

RESUMO

The present document offers an update on the recommendations for managing patients with cow's milk allergy - a disorder that manifests in the first year of life, with an estimated prevalence of 1.6-3% in this paediatric age group. The main causal allergens are the caseins and proteins in lactoserum (beta-lactoglobulin, alpha-lactoalbumin), and the clinical manifestations are highly variable in terms of their presentation and severity. Most allergic reactions affect the skin, followed by the gastrointestinal and respiratory systems, and severe anaphylaxis may occur. The diagnosis of cow's milk allergy is based on the existence of a suggestive clinical history, a positive allergy study and the subsequent application of controlled exposure testing, which constitutes the gold standard for confirming the diagnosis. The most efficient treatment for cow's milk allergy is an elimination diet and the use of adequate substitution formulas. The elimination diet must include milk from other mammals (e.g., sheep, goat, etc.) due to the risk of cross-reactivity with the proteins of cow's milk. Most infants with IgE-mediated cow's milk allergy become tolerant in the first few years of life. In those cases where cow's milk allergy persists, novel treatment options may include oral immunotherapy, although most authors do not currently recommend this technique in routine clinical practice. Enough evidence is not there to confirm the efficacy of elimination diets in the mother and infant for preventing the appearance of cow's milk allergy. Likewise, no benefits have been observed with prebiotic and probiotic dietetic supplements in infants for preventing food allergy


No disponible


Assuntos
Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Hipersensibilidade a Leite/diagnóstico , Hipersensibilidade a Leite/terapia , Hipersensibilidade a Leite/epidemiologia , Hipersensibilidade a Leite/patologia , Hipersensibilidade a Leite/prevenção & controle , Substitutos do Leite Humano , Aleitamento Materno , Imunoglobulina E , Proteínas do Leite/efeitos adversos , Dessensibilização Imunológica , Tolerância Imunológica , Eritema , Urticária , Dermatite Atópica , Imunoterapia , Administração Oral , Leite de Soja , Fórmulas Infantis , Dietoterapia/métodos , Hipersensibilidade Imediata
9.
Allergol Immunopathol (Madr) ; 43(5): 507-26, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25800671

RESUMO

The present document offers an update on the recommendations for managing patients with cow's milk allergy - a disorder that manifests in the first year of life, with an estimated prevalence of 1.6-3% in this paediatric age group. The main causal allergens are the caseins and proteins in lactoserum (beta-lactoglobulin, alpha-lactoalbumin), and the clinical manifestations are highly variable in terms of their presentation and severity. Most allergic reactions affect the skin, followed by the gastrointestinal and respiratory systems, and severe anaphylaxis may occur. The diagnosis of cow's milk allergy is based on the existence of a suggestive clinical history, a positive allergy study and the subsequent application of controlled exposure testing, which constitutes the gold standard for confirming the diagnosis. The most efficient treatment for cow's milk allergy is an elimination diet and the use of adequate substitution formulas. The elimination diet must include milk from other mammals (e.g., sheep, goat, etc.) due to the risk of cross-reactivity with the proteins of cow's milk. Most infants with IgE-mediated cow's milk allergy become tolerant in the first few years of life. In those cases where cow's milk allergy persists, novel treatment options may include oral immunotherapy, although most authors do not currently recommend this technique in routine clinical practice. Enough evidence is not there to confirm the efficacy of elimination diets in the mother and infant for preventing the appearance of cow's milk allergy. Likewise, no benefits have been observed with prebiotic and probiotic dietetic supplements in infants for preventing food allergy.


Assuntos
Hipersensibilidade a Leite , Biomarcadores/sangue , Dessensibilização Imunológica , Dietoterapia/métodos , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Hipersensibilidade a Leite/diagnóstico , Hipersensibilidade a Leite/imunologia , Hipersensibilidade a Leite/terapia , Proteínas do Leite/efeitos adversos , Proteínas do Leite/imunologia , Prognóstico , Testes Cutâneos
10.
Auton Neurosci ; 185: 8-28, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24956963

RESUMO

The vas deferens is a simple bioassay widely used to study the physiology of sympathetic neurotransmission and the pharmacodynamics of adrenergic drugs. The role of ATP as a sympathetic co-transmitter has gained increasing attention and furthered our understanding of its role in sympathetic reflexes. In addition, new information has emerged on the mechanisms underlying the storage and release of ATP. Both noradrenaline and ATP concur to elicit the tissue smooth muscle contractions following sympathetic reflexes or electrical field stimulation of the sympathetic nerve terminals. ATP and adenosine (its metabolic byproduct) are powerful presynaptic regulators of co-transmitter actions. In addition, neuropeptide Y, the third member of the sympathetic triad, is an endogenous modulator. The peptide plus ATP and/or adenosine play a significant role as sympathetic modulators of transmitter's release. This review focuses on the physiological principles that govern sympathetic co-transmitter activity, with special interest in defining the motor role of ATP. In addition, we intended to review the recent structural biology findings related to the topology of the P2X1R based on the crystallized P2X4 receptor from Danio rerio, or the crystallized adenosine A2A receptor as a member of the G protein coupled family of receptors as prototype neuro modulators. This review also covers structural elements of ectonucleotidases, since some members are found in the vas deferens neuro-effector junction. The allosteric principles that apply to purinoceptors are also reviewed highlighting concepts derived from receptor theory at the light of the current available structural elements. Finally, we discuss clinical applications of these concepts.


Assuntos
Junção Neuroefetora/fisiologia , Ducto Deferente/fisiologia , Animais , Epitélio/fisiologia , Humanos , Masculino , Junção Neuroefetora/anatomia & histologia , Receptores Purinérgicos/metabolismo , Ducto Deferente/anatomia & histologia
11.
Theor Appl Genet ; 126(10): 2467-75, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23807636

RESUMO

Two bread wheat lines each with a translocation on chromosome 7DL from either Thinopyrum intermedium (TC5 and TC14) or Thinopyrum ponticum (T4m), were hybridized in a ph1b mutant background to enhance recombination between the two translocated chromosomal segments. The frequency of recombinants was high in lines derived from the larger and similar-sized translocations (TC5/T4m), but much lower when derived from different-sized translocations (TC14/T4m). Recombinant translocations contained combinations of resistance genes Bdv2, Lr19 and Sr25 conferring resistance to Barley yellow dwarf virus (BYDV), leaf rust and stem rust, respectively. Their genetic composition was identified using bioassays and molecular markers specific for the two progenitor Thinopyrum species. This set of 7DL Th. ponticum/intermedium recombinant translocations was termed the Pontin series. In addition to Thinopyrum markers, the size of the translocation was estimated with the aid of wheat markers mapped on each of the 7DL deletion bins. Bioassays for BYDV, leaf rust and stem rust were performed under greenhouse and field conditions. Once separated from ph1b background, the Pontin recombinant translocations were stable and showed normal inheritance in successive backcrosses. The reported Pontin translocations integrate important resistance genes in a single linkage block which will allow simultaneous selection of disease resistance. Combinations of Bdv2 + Lr19 or Lr19 + Sr25 in both long and short translocations, are available to date. The smaller Pontins, comprising only 20 % of the distal portion of 7DL, will be most attractive to breeders.


Assuntos
Resistência à Doença/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Poaceae/genética , Recombinação Genética/genética , Translocação Genética , Triticum/genética , Bioensaio , Pão , Segregação de Cromossomos/genética , Cromossomos de Plantas/genética , Marcadores Genéticos , Luteovirus/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Triticum/microbiologia , Triticum/virologia
12.
Nutr Hosp ; 27(4): 1160-5, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23165557

RESUMO

BACKGROUND: The incidence of obesity and its most feared comorbidity, diabetes mellitus type 2, is increasing and there would not seem to be any medical treatment to help control these pandemics. However, there is a bariatric surgery technique, the Roux-en-Y Gastric Bypass (RYGB), which is safe and not only helps control excess weight, but produces encouraging results in the control and remission of diabetes. METHODS: We present 15 selected patients with a BMI between 30 and 35 kg/mt² and diabetes type 2 who underwent a laparoscopic RYGB with of one-year follow-up. RESULTS: A total of 14 women and one man were operated with the following average values: age: 37 years, weight: 88.3 kg, BMI: 32.8 kg/mt², blood glucose: 120 ± 38.8 mg%, HbA1c: 7.6 ± 0.73. Forty percent (40%) suffered from high blood pressure and 33.3% were dyslipidemic. Average surgical time was 75 minutes, hospital length of stay was two days, and there was a low rate of complications and no mortality. Diabetes remission was achieved in 93% of cases with significant drops in blood glucose and HbA1c (p ≤ 0.05 and p ≤ 0.001 respectively), dyslipidemia was 100% controlled and hypertension was 83.3% controlled. CONCLUSIONS: RYGB in selected patients with obesity type 1 and diabetes mellitus type 2 is a safe and effective technique for metabolic control and obesity control.


Assuntos
Anastomose em-Y de Roux , Diabetes Mellitus Tipo 2/cirurgia , Obesidade/complicações , Obesidade/cirurgia , Adolescente , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Resultado do Tratamento , Adulto Jovem
13.
Curr Alzheimer Res ; 8(6): 678-85, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21605038

RESUMO

The anomalous aggregation of proteins into pathological filaments is a common feature of a many human diseases, often related to aging. In this context, neurodegenerative pathologies such as Alzheimer's disease (AD) account for a major part of these protein misfolding diseases. AD is characterized by pathological aggregation of two proteins, tau and Aß-amyloid. The intracellular neurofibrillary tangles (NFTs) and neuropil threads consists of filaments of the modified microtubule-associated protein tau, while extracellular amyloid plaques consists of filaments of Aß-peptide. It is noteworthy that tau oligomers with a prefilamentous structure appear to play a role at early stages of AD and tauopathies, but also in asymptomatic patients with Braak-stage I neuropathology, where clinical symptoms of AD and NFTs in frontal cortex are absent. This suggests that an increase in tau oligomers levels occurs before individuals manifest clinical symptoms of AD. NFTs are one of the hallmarks of Alzheimer disease and other tauphaties. These aggregates are thought to be toxic to neurons, either by causing some neurotoxic signalling defects or by obstructing the cell function. Factors contributing to accumulation of tau aggregates include the increased rate of protein misfolding, generation of amyloidogenic oligomers, underactivity of repair systems such as chaperones and ubiquitin-proteasome system, or a failure of energy supply and antioxidant defense mechanisms. There is not clear evidence if the aggregated tau or oligomers cause cellular damage, but on the basis of the emergent need to have an early and effective treatment, lowering the production or removal of these aggregates appears as a pathway toward alleviating the disease. In the context of some of most relevant reports, we analyze why tau protein seems to be an interesting target for AD treatment, and the importance to understand the pathways of tau. aggregation. This knowledge will allow us to identify and optimize potential inhibitors that interact with aggregated forms of tau and hyperphosphorylated tau before the formation of the NFTs, offering a possible therapeutic route for AD treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Tauopatias/tratamento farmacológico , Proteínas tau/metabolismo , Doença de Alzheimer/metabolismo , Humanos , Emaranhados Neurofibrilares/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Tauopatias/metabolismo
14.
Asian Pac J Trop Biomed ; 1(4): 279-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23569775

RESUMO

OBJECTIVE: To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of feeding. METHODS: In a three-story building, triatomines were captured by direct search and electric vacuum cleaner search in and outside the building. Then, age structure of the captured Triatoma maculata (T. maculata) were identified and recorded. Reptiles living in sympatric with the triatomines were also searched. RESULTS: T. maculata were found living sympatric with geckos (Thecadactylus rapicauda) and they bit residents of the apartment building in study. A total of 1 448 individuals of T. maculata were captured within three days, of which 74.2% (1 074 eggs) were eggs, 21.5% were nymphs at different stages, and 4.3% were adults. CONCLUSIONS: The association of T. maculata and T. rapicauda is an effective strategy of colonizing dwellings located in the vicinity of the habitat where both species are present; and therefore, could have implications of high importance in the intradomiciliary transmission of Chagas disease.


Assuntos
Cordados/parasitologia , Ecossistema , Triatoma/crescimento & desenvolvimento , Trypanosoma cruzi/isolamento & purificação , Adulto , Animais , Doença de Chagas/transmissão , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Répteis/parasitologia , Venezuela
15.
Genome ; 52(6): 537-46, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19483772

RESUMO

Resistance to both barley yellow dwarf virus (BYDV) and cereal yellow dwarf virus (CYDV) has been demonstrated in wheat genetic stocks with Thinopyrum intermedium chromatin. A number of resistance-bearing translocations have been reported on chromosome arm 7DL from two independent Th. intermedium sources; one source is the addition line L1 and the other is the spontaneous substitution line P29. Another source of resistance in wheat cytogenetic stocks is available as a 2Ai(2D) substitution line. We used a set of 38 molecular markers and the available deletion stocks to compare the size of the 7DL translocations more comprehensively than has been done previously. We also compared the efficacy of BYDV resistance of the various genetic stocks both before and after transfer to a common genetic background. TC14 was confirmed as carrying the smallest translocation, replacing about 20% of the distal end of 7DL. TC5 and TC10 had 90% of the chromosome arm replaced by Th. intermedium chromatin; the proximal 10% corresponded to wheat chromatin. YW642 appeared to have the whole 7DL replaced by Th. intermedium chromatin, as confirmed by the co-dominant marker cfd68 mapping on the bin nearest the centromere. Translocation line P961341 had bins 3, 7, and 8 replaced by Th. intermedium chromatin, making this the second smallest translocation with BYDV and CYDV resistance. The translocation sizes reported here differ from some of the previous estimates. The translocated Th. intermedium segments appeared to be bigger than the replaced wheat 7DL fragments. All the resistances derived from the L1 and P29 group 7 chromosomes and the 2Ai#2 chromosome were effective in reducing the number of infected plants and the mean virus titre, regardless of the background. Some evidence is discussed suggesting the long arm of the Th. intermedium group 7 chromosome 7Ai#1 carries two resistances, the distal Bdv2 and a proximal second gene.


Assuntos
Imunidade Inata/genética , Luteovirus/patogenicidade , Doenças das Plantas/genética , Poaceae/genética , Translocação Genética/genética , Triticum/genética , Triticum/virologia , Mapeamento Cromossômico , Cromossomos de Plantas , DNA de Plantas , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase , Recombinação Genética
16.
Allergol. immunopatol ; 37(cong): 7-10, mayo 2009.
Artigo em Espanhol | IBECS | ID: ibc-144843

RESUMO

La inmunoterapia específica con alérgenos es el único tratamiento capaz de modifi car el curso natural de las enfermedades alérgicas, siendo más efi caz cuanto más precozmente se inicie. Sin embargo, las recomendaciones de la OMS continúan considerando la edad inferior a 5 años como una contraindicación relativa. De todas formas, las últimas revisiones bibliográficas consideran iniciar el tratamiento con inmunoterapia en niños menores de 5 años afectos, sobre todo, de asma bronquial (AU)


No disponible


Assuntos
Pré-Escolar , Humanos , Dessensibilização Imunológica/métodos , Asma/terapia , Administração por Inalação , Segurança do Paciente/estatística & dados numéricos , Asma/imunologia , Resultado do Tratamento
17.
Ultrasound Obstet Gynecol ; 32(4): 515-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18683279

RESUMO

OBJECTIVE: To evaluate parameters of fetal breathing movements-displacement of the fetal abdominal wall during inspiration and expiration, time of inspiration and expiration and speed of inspiration and expiration-between 30 and 36 weeks' gestation in normal pregnancies, and in those complicated by gestational diabetes or maternal hypertension. METHODS: Three categories of pregnancy were investigated: 49 were normal, 16 had pregnancy-induced diabetes and 10 were hypertensive. According to their gestational age, the patients were divided into two groups: Group A between 30 and 32 weeks' gestation and Group B between 33 and 36 weeks. Using photogrammetry and a computer-operated algorithm, six parameters of fetal breathing movements were investigated. RESULTS: There were significant differences in the various fetal parameters measured among the three categories of pregnant women. Up until 32 weeks of gestation, the displacements during inspiration and expiration were larger, the speeds of inspiration and expiration were higher, and the times for inspiration and expiration were shorter in the diabetic and hypertensive groups than in the normal group. In the later period, between 33 and 36 weeks, fetuses of pregnancy-induced diabetic patients showed the lowest inspiration and expiration times and the highest speeds of inspiration and expiration. CONCLUSIONS: Photogrammetry in conjunction with a computer-operated algorithm can be used to assess fetal breathing movements. There are significant differences in fetal breathing movements between normal pregnancies and those that are complicated by gestational diabetes or hypertension.


Assuntos
Movimento Fetal/fisiologia , Feto/fisiologia , Complicações na Gravidez , Mecânica Respiratória , Adulto , Diabetes Gestacional , Feminino , Monitorização Fetal/métodos , Idade Gestacional , Humanos , Hipertensão , Fotogrametria/métodos , Gravidez , Complicações Cardiovasculares na Gravidez , Terceiro Trimestre da Gravidez
18.
Cir. plást. ibero-latinoam ; 33(4): 221-232, oct.-dic. 2007. ilus, tab, graf
Artigo em Es | IBECS | ID: ibc-058648

RESUMO

La lipoaspiración, técnica tradicional usada para el tratamiento de las lipodistrofias con cicatrices mínimas, ha sido a través de los años mejorada con los avances anestésicos, farmacológicos y de instrumental. A su vez han aparecido otras técnicas que han publicitado ventajas respecto al tiempo de recuperación, sintomatología y resultados estéticos. Una de estas técnicas es la laserlipolisis a la que se atribuye menos dolor, menos equimosis y rápido postoperatorio. No se encuentran trabajos que acrediten estas ventajas, por lo que decidimos estudiar si existen ventajas de laserlipolisis en comparación con la lipoaspiración tradicional respecto del dolor, síntoma importante a considerar en el postoperatorio. Para esto se diseñó un trabajo prospectivo randomizado con una muestra de 60 pacientes a los cuales se aplicaron las dos técnicas en diferentes áreas y al mismo paciente. Se evaluó el dolor con escala numérica analógica a las 4 horas, 48 horas y 5 días de postoperatorio. Los resultados mostraron que la laserlipolisis presenta menos dolor en los muslos medido a las 48 horas y 5 días de la intervención. No hay diferencias entre estas dos técnicas en las otras zonas medidas como abdomen, áreas pretrocantéreas (“alforjas”), zona lumbar y pectoral. Considerando todos los pacientes sin diferenciar la técnica usada, las “alforjas” a las 4 horas duelen menos que el abdomen y a los 5 días duelen menos los muslos que el abdomen. No encontramos relación entre volumen aspirado e intensidad del dolor (AU)


The traditional suction-assisted lipoplasty, is a well established and commonly performed technique used for the treatment of lipodystrophias, which has undergone improvements with advances in anesthetics, pharmacology and introduction of new instruments. New techniques have appeared, promising advantages in recovery periods, symptomathology and aesthetic results when compared to the traditional suction- assisted lipoplasty. One of these newly introduced techniques is the laser-assisted lipoplasty (laserlipolysis), which claims less pain, less bruising and faster postoperative recovery. No evidence has been published to support these advantages when comparing laser-assisted lipoplasty to the traditional method, specifically when refering to pain, an important symptom to be taken into consideration in the postoperative period. For this reason we designed a prospective, randomized clinical study comprising 60 patients to which the two techniques were applied to different body areas. Pain was assessed using the numeric analog scale at 4 and 48 hours, and at 5 days after surgery. Evidence showed that laserlipolysis results in less pain of the thighs measured at 48 hours and 5 days after surgery. No difference in pain was found between both techniques on the other body areas evaluated (abdomen, trochanteric bulge, lumbar and pectoral areas). Assesing all patients, independent of the technique used, trochanteric bulge at 4 hours was found to be less painful than the abdominal area, and at 5 day evaluation the thighs were less painful than the abdominal area. No relationship was found between pain intensity and lipoaspirated volume


Assuntos
Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Humanos , Dor Pós-Operatória/diagnóstico , Lipectomia/métodos , Estudos Prospectivos , Terapia a Laser , Dor Pós-Operatória/epidemiologia , Medição da Dor/métodos , Analgesia/métodos
19.
Theor Appl Genet ; 116(1): 63-75, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17906848

RESUMO

Rusts and barley yellow dwarf virus (BYDV) are among the main diseases affecting wheat production world wide for which wild relatives have been the source of a number of translocations carrying resistance genes. Nevertheless, along with desirable traits, alien translocations often carry deleterious genes. We have generated recombinants in a bread wheat background between two alien translocations: TC5, ex-Thinopyrum (Th) intermedium, carrying BYDV resistance gene Bdv2; and T4m, ex-Th. ponticum, carrying rust resistance genes Lr19 and Sr25. Because both these translocations are on the wheat chromosome arm 7DL, homoeologous recombination was attempted in the double hemizygote (TC5/T4m) in a background homozygous for the ph1b mutation. The identification of recombinants was facilitated by the use of newly developed molecular markers for each of the alien genomes represented in the two translocations and by studying derived F(2), F(3) and doubled haploid populations. The occurrence of recombination was confirmed with molecular markers and bioassays on families of testcrosses between putative recombinants and bread wheat, and in F(2) populations derived from the testcrosses. As a consequence it has been possible to derive a genetic map of markers and resistance genes on these previously fixed alien linkage blocks. We have obtained fertile progeny carrying new tri-genomic recombinant chromosomes. Furthermore we have demonstrated that some of the recombinants carried resistance genes Lr19 and Bdv2 yet lacked the self-elimination trait associated with shortened T4 segments. We have also shown that the recombinant translocations are fixed and stable once removed from the influence of the ph1b. The molecular markers developed in this study will facilitate selection of individuals carrying recombinant Th. intermedium-Th. ponticum translocations (Pontin series) in breeding programs.


Assuntos
Doenças das Plantas/genética , Poaceae/genética , Recombinação Genética , Translocação Genética , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Cruzamentos Genéticos , DNA de Plantas/genética , Doenças das Plantas/virologia , Triticum/virologia
20.
Am Nat ; 168(3): 318-22, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16947107

RESUMO

In contrast to insect and animal populations, little attention has been directed to the study of cycles in plant populations. It has been argued on theoretical grounds that plants present stable dynamics. Nevertheless, there are examples where plant populations appear to exhibit oscillatory dynamics, but the oscillatory signal is variable and comes from very short time series data. Using a combination of time series, models, and empirical results, we present evidence of population cycles for Descurania sophia in a 16-year field experiment. Endogenous and exogenous causal mechanisms were studied to identify processes underlying this temporal dynamic. Our results show a 4-year cycle produced by delayed density dependence. We suggest that high nutrient levels might be responsible for the observed dynamics of D. sophia. Our results suggest that although plant population dynamics may be stabilized by direct density dependence, delayed density dependence could destabilize dynamics.


Assuntos
Brassicaceae/fisiologia , Modelos Biológicos , Dinâmica Populacional , Fatores de Tempo
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