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1.
Plant Biol (Stuttg) ; 22(6): 1030-1040, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32757407

RESUMO

Acremonium strictum Elicitor Subtilisin (AsES) is a fungal elicitor that activates innate immunity, conferring disease resistance in strawberry (Fragaria × ananassa Duch.), Arabidopsis and other plant species. The aim of the present work was to evaluate the involvement of the ethylene (ET) signalling pathway in AsES-mediated immune response in strawberry. Ethylene production and expression of the genes responsible for ET synthesis, perception and response were measured after AsES treatment. ROS (H2 O2 ) accumulation and immunity induced by AsES were studied after ET perception was blocked by 1-methylcyclopropene (1-MCP). Biochemical and molecular results showed that AsES induced a marked increase in local and systemic biosynthesis of ET, both in a biphasic manner. Blocking of ET perception by 1-MCP prior to AsES induction reduced production of ROS (H2 O2 ) and prevented AsES from eliciting defence against fungal pathogens having different lifestyles, such as Botrytis cinerea (necrotrophic) and Colletotrichum acutatum (hemibiotrophic). These findings contribute to elucidate the mode of action of the novel elicitor subtilase, AsES, specifically regarding the role of ET signalling in the activation of plant innate immunity, in addition to the multitude of processes regulated by ET in plants.


Assuntos
Etilenos , Fragaria , Transdução de Sinais , Subtilisina , Etilenos/metabolismo , Fragaria/efeitos dos fármacos , Fragaria/imunologia , Fragaria/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hypocreales/química , Transdução de Sinais/efeitos dos fármacos , Subtilisina/farmacologia
2.
Appl Environ Microbiol ; 85(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824454

RESUMO

Different Bacillus species with PGPR (plant growth-promoting rhizobacterium) activity produce potent biofungicides and stimulate plant defense responses against phytopathogenic fungi. However, very little is known about how these PGPRs recognize phytopathogens and exhibit the antifungal response. Here, we report the antagonistic interaction between Bacillus subtilis and the phytopathogenic fungus Fusarium verticillioides We demonstrate that this bacterial-fungal interaction triggers the induction of the SigB transcription factor, the master regulator of B. subtilis stress adaptation. Dual-growth experiments performed with live or dead mycelia or culture supernatants of F. verticillioides showed that SigB was activated and required for the biocontrol of fungal growth. Mutations in the different regulatory pathways of SigB activation in the isogenic background revealed that only the energy-related RsbP-dependent arm of SigB activation was responsible for specific fungal detection and triggering the antagonistic response. The activation of SigB increased the expression of the operon responsible for the production of the antimicrobial cyclic lipopeptide surfactin (the srfA operon). SigB-deficient B. subtilis cultures produced decreased amounts of surfactin, and B. subtilis cultures defective in surfactin production (ΔsrfA) were unable to control the growth of F. verticillioidesIn vivo experiments of seed germination efficiency and early plant growth inhibition in the presence of F. verticillioides confirmed the physiological importance of SigB activity for plant bioprotection.IMPORTANCE Biological control using beneficial bacteria (PGPRs) represents an attractive and environment-friendly alternative to pesticides for controlling plant diseases. Different PGPR Bacillus species produce potent biofungicides and stimulate plant defense responses against phytopathogenic fungi. However, very little is known about how PGPRs recognize phytopathogens and process the antifungal response. Here, we report how B. subtilis triggers the induction of the stress-responsive sigma B transcription factor and the synthesis of the lipopeptide surfactin to fight the phytopathogen. Our findings show the participation of the stress-responsive regulon of PGPR Bacillus in the detection and biocontrol of a phytopathogenic fungus of agronomic impact.


Assuntos
Bacillus subtilis/química , Proteínas de Bactérias/genética , Fungicidas Industriais/farmacologia , Fusarium/fisiologia , Fator sigma/farmacologia , Bacillus subtilis/genética , Proteínas de Bactérias/metabolismo , Doenças das Plantas/prevenção & controle , Fator sigma/genética , Fator sigma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/farmacologia
3.
J Bacteriol ; 201(2)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30396900

RESUMO

Bacterial biofilms are important in natural settings, biotechnology, and medicine. However, regulation of biofilm development and its persistence in different niches is complex and only partially understood. One key step during the biofilm life cycle is dispersal, when motile cells abandon the mature biofilm to spread out and colonize new niches. Here, we show that in the model bacterium Bacillus subtilis the general stress transcription factor SigB is essential for halting detrimental overgrowth of mature biofilm and for triggering dispersal when nutrients become limited. Specifically, SigB-deficient biofilms were larger than wild-type biofilms but exhibited accelerated cell death, significantly greater sensitivity to different stresses, and reduced dispersal. Interestingly, the signal detected by SigB to limit biofilm growth was transduced through the RsbP-dependent metabolic arm of the SigB regulatory cascade, which in turn positively controlled expression of SinR, the master regulator of biofilm formation and cell motility. This novel SigB-SinR regulatory circuit might be important in controlling the fitness of biofilms (either beneficial or harmful) in diverse environments.IMPORTANCE Biofilms are crucial for bacterial survival, adaptation, and dissemination in natural, industrial, and medical systems. Sessile cells embedded in the self-produced extracellular matrix of the biofilm benefit from a division of labor and are protected from environmental insults. However, as the biofilm ages, cells become stressed because of overcrowding, starvation, and accumulation of waste products. How does the sessile biofilm community sense and respond to stressful conditions? Here, we show that in Bacillus subtilis, the transcription factors SigB and SinR control whether cells remain in or leave a biofilm when metabolic conditions become unfavorable. This novel SigB-SinR regulatory circuit might be important for controlling the fitness of biofilms (either beneficial or harmful) in diverse environments.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Fator sigma/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Meios de Cultura/química , Locomoção , Metabolismo , Fator sigma/deficiência
4.
J Environ Manage ; 226: 249-255, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121460

RESUMO

The degradation of pesticide diuron has been explored by photoelectrocatalysis (PEC) under visible light illumination using two different WO3 nanostructures, obtained by anodization of tungsten. The highest degradation efficiency (73%) was obtained for WO3 nanosheets synthesized in the presence of small amounts of hydrogen peroxide (0.05 M). For that nanostructure, the kinetic coefficient for diuron degradation was 133% higher than that for the other nanostructure (anodized in the presence of fluoride anions). These results have been explained by taking into account the different architecture and dimensions of the two WO3 nanostructures under study.


Assuntos
Diurona/química , Luz , Nanoestruturas , Diurona/isolamento & purificação , Óxidos , Tungstênio
5.
Am J Transplant ; 15(11): 2825-36, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26139432

RESUMO

CD40-CD154 pathway blockade prolongs renal allograft survival in nonhuman primates (NHPs). However, antibodies targeting CD154 were associated with an increased incidence of thromboembolic complications. Antibodies targeting CD40 prolong renal allograft survival in NHPs without thromboembolic events but with accompanying B cell depletion, raising the question of the relative contribution of B cell depletion to the efficacy of anti-CD40 blockade. Here, we investigated whether fully silencing Fc effector functions of an anti-CD40 antibody can still promote graft survival. The parent anti-CD40 monoclonal antibody HCD122 prolonged allograft survival in MHC-mismatched cynomolgus monkey renal allograft transplantation (52, 22, and 24 days) with accompanying B cell depletion. Fc-silencing yielded CFZ533, an antibody incapable of B cell depletion but still able to potently inhibit CD40 pathway activation. CFZ533 prolonged allograft survival and function up to a defined protocol endpoint of 98-100 days (100, 100, 100, 98, and 76 days) in the absence of B cell depletion and preservation of good histological graft morphology. CFZ533 was well-tolerated, with no evidence of thromboembolic events or CD40 pathway activation and suppressed a gene signature associated with acute rejection. Thus, use of the Fc-silent anti-CD40 antibody CFZ533 appears to be an attractive approach for preventing solid organ transplant rejection.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD40/imunologia , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Transplante de Rim/métodos , Animais , Ligante de CD40/imunologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Transplante de Rim/efeitos adversos , Macaca fascicularis , Masculino , Distribuição Aleatória , Fatores de Tempo , Imunologia de Transplantes/fisiologia , Transplante Homólogo
6.
Mol Immunol ; 63(2): 456-63, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25451975

RESUMO

The effects of the Fc silencing mutations such as leucine (L) to alanine (A) substitution at the position 234 and 235 (LALA) and the alanine (A) to asparagine (N) substitution at position 297 (N297A) are well investigated for human IgG. However, the effects of the same two silencing Fc mutations in a mouse IgG backbone are not yet well investigated in respect to binding to mouse Fc gamma receptors (FcγRs), complement and subsequent effector functions. By using a mouse IgG2a tool antibody directed against mouse OX40L, we demonstrate a strongly reduced binding of the two Fc mutants to high and low affinity recombinant and cell expressed mouse FcγRs, when compared to the mouse IgG2a with the wild type (wt) backbone. Reduced FcγR binding by the two investigated Fc mutants could further be confirmed on primary mouse macrophages expressing their native FcγRs. In addition, we reveal that the LALA and N297A mutations in the mIgG2a also slightly reduced binding to C1q of human origin. Thus, here we provide experimental evidence that the two investigated Fc mutations in the mouse IgG backbone lead to similar "silencing" properties as previously demonstrated for the human IgG and thus represent a useful method to alter effector functions in tool antibodies to be used in mouse models.


Assuntos
Engenharia Genética , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Mutação/genética , Receptores de IgG/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Complemento C1q/metabolismo , Citometria de Fluxo , Humanos , Imunoglobulina G/química , Macrófagos/metabolismo , Camundongos , Dados de Sequência Molecular , Proteínas Mutantes/metabolismo , Ligante OX40/metabolismo , Ligação Proteica , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
7.
J Food Sci Technol ; 51(11): 3072-82, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396299

RESUMO

Finger millet (Elucine corocana), locally known as ragi, and probiotics have been recognized for their health benefits. In the present work we describe novel probiotic ragi malt (functional food) that has been prepared using ragi and probiotic Leuconostoc mesenteroides (Lm) and Bacillus subtilis natto (Bs), alone and in combination, for antagonistic activity against Vibrio cholerae (Vc). In vitro studies using pure cultures showed that each probiotic strain (Lm or Bs) was able to inhibit the planktonic growth of Vc as well as its ability to make biofilms and adhere to extracellular matrix proteins (fibronectin, Fn) that may function in vivo as initial ports of entrance of the pathogen. Interestingly, the combination of both probiotic strains (Lm plus Bs) produced the strongest activity against the Vc. When both cultures were used together in the ragi malt the antimicrobial activity against Vc was enhanced due to synergistic effect of both probiotic strains. The inclusion of both probiotic strains in the functional food produced higher amounts of beneficial fatty acids like linoleic and linolenic acid and increased the mineral content (iron and zinc). The viability and activity of Lm and Bs against Vc was further enhanced with the use of adjuvants like ascorbic acid, tryptone, cysteine hydrochloride and casein hydrolysate in the ragi malt. In sum, the intake of probiotic ragi malt supplemented with Lm and Bs may provide nutrition, energy, compounds of therapeutic importance and antagonistic activity against Vc to a large extent to the consumer.

10.
Microb Pathog ; 52(1): 85-91, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22079896

RESUMO

Histotoxic strains of Clostridium perfringens cause human gas gangrene, a devastating infection during which potent tissue-degrading toxins are produced and secreted. Although this pathogen only grows in anaerobic-nutrient-rich habitats such as deep wounds, very little is known regarding how nutritional signals influence gas gangrene-related toxin production. We hypothesize that sugars, which have been used throughout history to prevent wound infection, may represent a nutritional signal against gas gangrene development. Here we demonstrate, for the first time, that sugars (sucrose, glucose) inhibited the production of the main protein toxins, PLC (alpha-toxin) and PFO (theta-toxin), responsible for the onset and progression of gas gangrene. Transcription analysis experiments using plc-gusA and pfoA-gusA reporter fusions as well as RT-PCR analysis of mRNA transcripts confirmed that sugar represses plc and pfoA expression. In contrast an isogenic C. perfringens strain that is defective in CcpA, the master transcription factor involved in carbon catabolite response, was completely resistant to the sugar-mediated inhibition of PLC and PFO toxin production. Furthermore, the production of PLC and PFO toxins in the ccpA mutant strain was several-fold higher than the toxin production found in the wild type strain. Therefore, CcpA is the primary or unique regulatory protein responsible for the carbon catabolite (sugar) repression of toxin production of this pathogen. The present results are analyzed in the context of the role of CcpA for the development and aggressiveness of clostridial gas gangrene and the well-known, although poorly understood, anti-infective and wound healing effects of sugars and related substances.


Assuntos
Toxinas Bacterianas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Clostridium perfringens/metabolismo , Regulação para Baixo , Gangrena Gasosa/microbiologia , Glucose/metabolismo , Proteínas Hemolisinas/metabolismo , Sacarose/metabolismo , Fosfolipases Tipo C/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/genética , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Clostridium perfringens/enzimologia , Clostridium perfringens/genética , Regulação Bacteriana da Expressão Gênica , Proteínas Hemolisinas/genética , Humanos , Fosfolipases Tipo C/genética
11.
Pediatr. aten. prim ; 13(51): 387-396, jul.-sept. 2011. tab
Artigo em Espanhol | IBECS | ID: ibc-91248

RESUMO

Objetivo: valorar el entorno familiar y los hábitos de la población adolescente de nuestra área para detectar posibles factores asociados con alteraciones de la autoimagen o un mayor riesgo de presentar un trastorno de la alimentación. Material y métodos: 158 entrevistas a adolescentes que cursaban 1.º y 2.º de Enseñanza Secundaria Obligatoria, recogiendo sexo, edad, entorno familiar y social, horas de pantallas y contenidos, horas de deporte, horas de lectura y contenidos, autoimagen, test de actitud ante la alimentación (EAT-26) y somatometría. Resultados: el análisis de regresión logística mostró una asociación estadísticamente significativa entre la autoimagen correcta y las horas de deporte practicado (B = 0,11; p = 0,047), el hecho de tener hermanos (B = -1,4; p = 0,019), la puntuación total en el EAT-26 (B = -0,06; p = 0,005) y el índice de masa corporal (B = -0,1; p = 0,031). Conclusiones: el fomento del ejercicio físico y la difusión de ideas correctas sobre la imagen corporal pueden influir positivamente en una mejor autoimagen de la población adolescente y, del mismo modo, ayudar a prevenir posibles trastornos de la alimentación (AU)


Objetive: To evaluate familiar environment and habits of teenager population from our area to detect factors associated with alterations of self-image or an increased risk of presenting an eating disorder. Methods: One hundred and fifty-eight teenagers from first to second course of ESO (Obligatory Secondary Education) were interviewed collecting information about gender, age, family and social environment, time of screens viewing and contents, time of sport practicing, time of reading and contents, self-image, Eating Attitudes Test (EAT-26) and anthropometry. Results: The logistic regression showed a statistically significant association between self-image and time of sport practicing (B = 0.11; p = 0.047), having brothers (B =-1.4; p = 0.019), total punctuation on EAT-26 (B =-0.06; p = 0.005) and Body Mass Index (B =-0.1; p = 0.031). Conclusions: Promotion of sport practicing and healthy ideas about body image could improve teenager self-image and help to prevent the development of eating disorders (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Autoimagem , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Comportamento do Adolescente/fisiologia , Comportamento do Adolescente/psicologia , Exercício Físico/fisiologia , Esportes/fisiologia , Imagem Corporal , Esportes/estatística & dados numéricos , Modelos Logísticos , Índice de Massa Corporal , Esforço Físico/fisiologia
12.
Br J Dermatol ; 164(3): 465-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21039412

RESUMO

The initial appearance of subacute cutaneous lupus erythematosus (SCLE) skin lesions in conjunction with Ro/SS-A autoantibodies occurring as an adverse reaction to hydrochlorothiazide [i.e. drug-induced SCLE (DI-SCLE)] was first reported in 1985. Over the past decade an increasing number of drugs in different classes has been implicated as triggers for DI-SCLE. The management of DI-SCLE can be especially challenging in patients taking multiple medications capable of triggering DI-SCLE. Our objectives were to review the published English language literature on DI-SCLE and use the resulting summary data pool to address questions surrounding drug-induced SCLE and to develop guidelines that might be of value to clinicians in the diagnosis and management of DI-SCLE. A systematic review of the Medline/PubMed-cited literature on DI-SCLE up to August 2009 was performed. Our data collection and analysis strategies were prospectively designed to answer a series of questions related to the clinical, prognostic and pathogenetic significance of DI-SCLE. One hundred and seventeen cases of DI-SCLE were identified and reviewed. White women made up the large majority of cases, and the mean overall age was 58·0 years. Triggering drugs fell into a number of different classes, highlighted by antihypertensives and antifungals. Time intervals ('incubation period') between drug exposure and appearance of DI-SCLE varied greatly and were drug class dependent. Most cases of DI-SCLE spontaneously resolved within weeks of drug withdrawal. Ro/SS-A autoantibodies were present in 80% of the cases in which such data were reported and most remained positive after resolution of SCLE skin disease activity. No significant differences in the clinical, histopathological or immunopathological features between DI-SCLE and idiopathic SCLE were detected. There is now adequate published experience to suggest that DI-SCLE does not differ clinically, histopathologically or immunologically from idiopathic SCLE. It should be recognized as a distinct clinical constellation differing clinically and immunologically from the classical form of drug-induced systemic lupus erythematosus.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Lúpus Eritematoso Cutâneo/induzido quimicamente , Anti-Inflamatórios não Esteroides/efeitos adversos , Anticonvulsivantes/efeitos adversos , Antifúngicos/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Antineoplásicos/efeitos adversos , Produtos Biológicos/efeitos adversos , Feminino , Antagonistas dos Receptores Histamínicos/efeitos adversos , Humanos , Fatores Imunológicos/efeitos adversos , Lúpus Eritematoso Cutâneo/imunologia , Lúpus Eritematoso Cutâneo/patologia , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/efeitos adversos , Terapia Ultravioleta/efeitos adversos
13.
Meat Sci ; 86(3): 600-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20667661

RESUMO

The influence of sodium chloride on the water holding capacity of meat is well known and described in literature. An increase in water holding capacity is associated with an increase in the swelling pressure in the protein matrix. A novel device was used to measure the swelling pressure during brine salting of muscle cylinders (40×50 mm), in different NaCl brine concentrations (2.5 to 25%) over 6 days at 4°C. Changes in meat composition, weight and height of non-constrained control samples were also measured. The aim of this work was to prove the feasibility of using the developed device in order to quantify the influence of the brine concentration on the magnitude of the swelling pressure. The obtained results indicated the adequacy of the developed device for measuring the meat swelling, while a good correlation of the swelling pressure and the changes in weight and height of the samples was observed.


Assuntos
Análise de Alimentos/métodos , Carne , Sais , Água/fisiologia , Animais , Carne/análise , Músculo Esquelético , Pressão , Cloreto de Sódio , Suínos
14.
Meat Sci ; 86(2): 331-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20541872

RESUMO

The reduction of added sodium chloride in dry-cured ham has been proposed to reduce dietary sodium intake in Mediterranean countries. The effect of substituting sodium chloride with potassium chloride, calcium chloride and magnesium chloride on some physicochemical characteristics of dry-cured ham during processing was evaluated. The results showed that hams salted with a mixture of sodium and potassium chloride registered higher salt concentrations and lower water contents and thus, needed less time to reach the required weight loss at the end of the process. The opposite effect was observed when calcium and magnesium chloride were added to the salt mixture. The observed differences in the texture and colour parameters were mainly due to differences in water and salt content.


Assuntos
Cloreto de Cálcio/farmacologia , Cloreto de Magnésio/farmacologia , Carne/análise , Cloreto de Potássio/farmacologia , Cloreto de Sódio na Dieta/farmacologia , Animais , Cloreto de Cálcio/análise , Bovinos , Cloreto de Magnésio/análise , Cloreto de Potássio/análise , Cloreto de Sódio na Dieta/análise , Suínos
15.
Res Vet Sci ; 89(2): 250-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20307896

RESUMO

On the basis of pharmacokinetic modeling, this study provides some insights into predicting in vivo plasma progesterone concentrations when using bovine intravaginal inserts for systemic progesterone delivery. More significantly, this contribution is the first attempt to build a simple pharmacokinetic model that links plasma progesterone concentrations with the hormone released from bovine intravaginal inserts. After evaluating three rival pharmacokinetic models and considering some phenomena involved in the intravaginal administration of progesterone, a primary pharmacokinetic model having a good data fitting capability with only two adjustable parameters is proposed to the above mentioned task. Kinetic parameters are given for lactating Holstein dairy cows with two levels of daily milk yields; and non-pregnant, non-lactating Holstein-Friesian cattle. Model predictions indicate the occurrence of a preferential distribution of the intravaginally administered progesterone dose through a first uterine pass effect.


Assuntos
Bovinos/sangue , Sincronização do Estro/métodos , Progesterona/sangue , Progesterona/farmacocinética , Administração Intravaginal , Animais , Indústria de Laticínios , Preparações de Ação Retardada , Feminino , Meia-Vida , Lactação , Modelos Biológicos , Gravidez , Progesterona/administração & dosagem
16.
J Dairy Sci ; 93(3): 988-99, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20172219

RESUMO

Progesterone pharmacokinetics were analyzed for plasma hormone concentrations ranging from linear to saturated metabolism in lactating Holstein cows with differing daily milk yields. The adequacy of 2-coupled first-order (bi-exponential equation), hyperbolic (Michaelis-Menten equation), and sigmoidal (Hill equation) kinetic models to describe the experimental progesterone pharmacokinetic profiles was examined on a statistical basis. After nonlinear regression and statistical analysis of the data-fitting capability, a simple one-compartment model based on Hill equation proved to be most adequate. This model indicates an enzyme-catalyzed metabolism of progesterone involving cooperative substrate-binding sites, resulting from allosteric effects that yield a sigmoidal saturation rate curve. Kinetic parameters were estimated for 2 groups of lactating Holstein cows with different daily milk yields. We found, for the first time, a remarkable quantitative agreement of the Hill coefficient value with that reported in pharmacokinetic studies involving cytochrome P450, family 3, subfamily A (CYP3A)-mediated reactions in other mammals, humans included. It seems that positive cooperativity makes enzymes much more sensitive to plasma progesterone concentration, and their activities can undergo significant changes in a narrow range of concentration as characteristic of sigmoidal behavior. Therefore, the values of classical pharmacokinetic parameters, such as the elimination constant, half-life, and clearance rate, were found to be highly dependent on the plasma progesterone concentration.


Assuntos
Bovinos/metabolismo , Lactação/fisiologia , Progesterona/farmacocinética , Progestinas/farmacocinética , Animais , Indústria de Laticínios , Feminino , Meia-Vida , Taxa de Depuração Metabólica , Leite/metabolismo , Modelos Biológicos , Progesterona/sangue , Análise de Regressão
17.
Pediatr. aten. prim ; 11(43): 413-423, jul.-sept. 2009.
Artigo em Espanhol | IBECS | ID: ibc-73730

RESUMO

Introducción: el presente estudio valora la antropometría, el desarrollo intelectual y lashabilidades sociales de los niños según su exposición al abuso de pantallas (televisión, videojuegos,ordenador).Material y métodos: 130 entrevistas a niños entre 5 y 10 años recogiendo: sexo, edad,entorno familiar, horas de pantallas, horas de deporte, somatometría, puntuación del gradode responsabilidad y sociabilidad y test de Goodenough (como estimación del cociente intelectual).Resultados: los modelos de regresión lineal múltiple mostraron una asociación estadísticamentesignificativa entre el índice de masa corporal (IMC) y las horas de televisión y vídeos(B = 0,06; p = 0,05) y entre el IMC y las horas de ordenador y videojuegos (B = 0,34; p <0,01), así como entre la estimación del cociente intelectual y las horas de ordenador y videojuegos(B = -1,67; p = 0,02).Conclusiones: deben desarrollarse estrategias para concienciar a las familias sobre losefectos perjudiciales del abuso de pantallas, tanto de los asociados al sedentarismo y a loscontenidos negativos, como del daño sobre el desarrollo intelectual que produce el abuso delos juegos electrónicos(AU9


Objective: the present study examines anthropometric measurements, mental developmentand social skills in children exposed to screen-viewing (television, video games, computer). Methods: one hundred and thirty interviews were addressed to children aged 5 to 10 years.Information about gender, age, family, screen-viewing time, sport-practicing time, anthropometricmeasurements, responsibility punctuation, sociability punctuation and Goodenough’stest (as estimation of intelligence quotient) was collected.Results: multiple regression models showed a statistically significant association betweenbody mass index (BMI) and television and video viewing time (B = 0.06; p = 0.05) andbetween BMI and computer and videogame use time (B = 0.34; p < 0.01), as well as betweenestimated intelligence quotient and computer and video game use time (B = -1.67; p = 0.02).Conclusions: screen-viewing abuse is associated with a higher risk of overweight. Electronicgames abuse is associated with a lower intelligence quotient. Wide strategies to warnfamilies about these risks are needed(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Saúde Mental , Antropometria/métodos , Inteligência/fisiologia , Jogos de Vídeo/efeitos adversos , Jogos de Vídeo/psicologia , Televisão/tendências , Aptidão/fisiologia , Competência Clínica/estatística & dados numéricos , Modelos Lineares , Índice de Massa Corporal
18.
Meat Sci ; 83(3): 423-30, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20416693

RESUMO

The consumption of cured meat products is not recommended to hypertensive consumers due to its high sodium content. This constitutes an important restriction for this industry, which is becoming more and more important due to the current trends in consumption. The partial replacement of sodium chloride by potassium chloride has been proposed as a possible strategy to reduce the sodium content of this type of products. The aim of this study was to evaluate the effect brought about by partial replacement of sodium chloride with potassium chloride (up to 70%) on physicochemical and microbiological parameters of dry-cured pork loin after the curing and drying process. The results showed that it is possible to obtain low sodium dry-cured loin, up to a 50% replacement of sodium by potassium, with similar physicochemical characteristics to the commercial product with usual amounts of sodium.

19.
Meat Sci ; 78(1-2): 135-42, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22062103

RESUMO

Dry-cured ham consumption is restricted by hypertensive consumers due to its high sodium content. This constitutes an important matter for this industry, being relevant due to the current trends in consumption. In order to prevent the problems related to the high sodium intake, one of the possibilities is the total or partial replacement of sodium by other ions, such as potassium, calcium and magnesium. The aim of this study was to characterise the post-salting stage in Spanish cured ham production with the results obtained after salting with low sodium salt content. The results showed that lower sodium hams needed more time of post-salting to reach similar water activity values than those achieved by hams salted with 100% NaCl. Nevertheless, no differences in microbial counts were observed among the studied batches, although a sharp decrease in microbiota was observed when the, post-salting time was prolonged in the lower sodium hams.

20.
Am Surg ; 71(11): 931-5; discussion 935-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16372611

RESUMO

Seroma formation has been documented as a common complication in laparoscopic ventral herniorraphy. However, there are no recent studies documenting the incidence of or protective strategies against seroma-related cellulitis. The purpose of this study was to evaluate 65 laparoscopic ventral herniorraphies and to determine if seroma-related cellulitis can be prevented by the routine use of postoperative prophylactic antibiotics. A retrospective case review of 65 laparoscopic ventral herniorraphies was done at our institution from February 2002 to January 2004. All were performed using either Gore-Tex DualMesh or Bard Composix mesh and performed under the direct supervision of a single surgeon. Twenty patients received only preoperative third-generation cephalosporins or fluoroquinolones. All other patients received either 7 days of postoperative oral cephalosporins or fluoroquinolones in addition to preoperative antibiotics. Sixty-five patients underwent laparoscopic ventral hernia repair. There were 45 patients in the postoperative antibiotic group and 20 patients in the preoperative-only antibiotic group. Twenty-one patients developed seromas. Twelve of these developed cellulitis. The rates of seroma formation were similar in the two groups with 30 per cent in the preoperative only group and 33 per cent in the postoperative antibiotic group. However, 100 per cent of the seromas in the preoperative antibiotic group developed seroma-related cellulitis. Only 40 per cent of seromas in the postoperative antibiotic group developed cellulitis. In addition, two seromas in the preoperative antibiotics-only group progressed to frank mesh infection necessitating operative removal. There were no complications related to antibiotic administration. Laparoscopic ventral hernia repair is a safe and effective procedure. Our seroma rate is 30 per cent and compares equally with prior reported studies. Seroma-related cellulitis is a common problem that can lead to mesh infection, postoperative morbidity, and further need for operative care. The administration of 7 days of postoperative prophylactic antibiotics appears to be a safe and effective means to limit seroma-related cellulitis.


Assuntos
Antibioticoprofilaxia , Celulite (Flegmão)/epidemiologia , Celulite (Flegmão)/prevenção & controle , Hérnia Ventral/cirurgia , Laparoscopia/efeitos adversos , Seroma/complicações , Celulite (Flegmão)/etiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Estudos Retrospectivos , Seroma/etiologia
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