RESUMO
Although different strategies to control biofilm formation on endotracheal tubes have been proposed, there are scarce scientific data on applying phages for both removing and preventing Pseudomonas aeruginosa biofilms on the device surface. Here, the anti-biofilm capacity of five bacteriophages was evaluated by a high content screening assay. We observed that biofilms were significantly reduced after phage treatment, especially in multidrug-resistant strains. Considering the anti-biofilm screens, two phages were selected as cocktail components, and the cocktail's ability to prevent colonization of the endotracheal tube surface was tested in a dynamic biofilm model. Phage-coated tubes were challenged with different P. aeruginosa strains. The biofilm growth was monitored from 24 to 168 h by colony forming unit counting, metabolic activity assessment, and biofilm morphology observation. The phage cocktail promoted differences of bacterial colonization; nonetheless, the action was strain dependent. Phage cocktail coating did not promote substantial changes in metabolic activity. Scanning electron microscopy revealed a higher concentration of biofilm cells in control, while tower-like structures could be observed on phage cocktail-coated tubes. These results demonstrate that with the development of new coating strategies, phage therapy has potential in controlling the endotracheal tube-associated biofilm.
RESUMO
The apolipoprotein B (APOB) gene contains several polymorphic sites described as risk modifiers for cardiovascular events. The objective of this study was to verify the association of the classic APOB Xba I polymorphism (rs693) with atherosclerotic risk factors in a segment of the Brazilian elderly population considering their usual dietary intake. Clinical and biochemical characteristics as well as total caloric and fat intake data were determined from 644 elderly individuals. Polymorphism analysis was performed by conventional polymerase chain reaction followed by enzyme restriction. Statistical analyses compared measures and proportions according to different APOB genotypic combinations. Statistically significant association was found between Xba I polymorphism and serum LDL, total cholesterol, and total lipid levels, with important elevations among T homozygotes compared to the other genotypes. There was homogeneity in all other parameters analyzed (including intake pattern), with a tendency for reduced levels of circulating apolipoprotein B among TT individuals. Our results pointed out that genetic variation in APOB affected the lipemic profile of elderly individuals in a context not biased by diet, generating a pattern suggestive of secretory disorder of lipoprotein particles, with possible implication in atherosclerotic risk.
Assuntos
Apolipoproteínas B/genética , Aterosclerose/genética , Comportamento Alimentar , Predisposição Genética para Doença/genética , Lipídeos/sangue , Polimorfismo Genético/genética , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/sangue , Brasil , Doenças Cardiovasculares/sangue , Ingestão de Energia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
The apolipoprotein B (APOB) gene contains several polymorphic sites described as risk modifiers for cardiovascular events. The objective of this study was to verify the association of the classic APOB Xba I polymorphism (rs693) with atherosclerotic risk factors in a segment of the Brazilian elderly population considering their usual dietary intake. Clinical and biochemical characteristics as well as total caloric and fat intake data were determined from 644 elderly individuals. Polymorphism analysis was performed by conventional polymerase chain reaction followed by enzyme restriction. Statistical analyses compared measures and proportions according to different APOB genotypic combinations. Statistically significant association was found between Xba I polymorphism and serum LDL, total cholesterol, and total lipid levels, with important elevations among T homozygotes compared to the other genotypes. There was homogeneity in all other parameters analyzed (including intake pattern), with a tendency for reduced levels of circulating apolipoprotein B among TT individuals. Our results pointed out that genetic variation in APOB affected the lipemic profile of elderly individuals in a context not biased by diet, generating a pattern suggestive of secretory disorder of lipoprotein particles, with possible implication in atherosclerotic risk.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas B/genética , Polimorfismo Genético/genética , Predisposição Genética para Doença/genética , Aterosclerose/genética , Comportamento Alimentar , Lipídeos/sangue , Brasil , Ingestão de Energia , Doenças Cardiovasculares/sangue , Fatores de Risco , Aterosclerose/sangue , Frequência do Gene , GenótipoRESUMO
In modern society, the intense vehicle traffic and the lack of effective mitigating strategies may adversely impact freshwater systems. Road-deposited sediments (RDS) accumulate a variety of toxic substances which are transported into nature during hydrologic events, mainly affecting water bodies through stormwater runoff. The aim of this study was to evaluate the RDS metal enrichment ratio between the end of wet season and the middle of the dry season for Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in samples from Natal, Brazil. Twenty RDS, drainage system and river sediment samples were collected in the wet and dry seasons using a stainless-steel pan, brush and spatula. In the laboratory, the samples were submitted to acid digestion and heavy metal concentrations were measured by atomic absorption spectrometry (AAS). A consistent RDS enrichment by heavy metals in dry season samples was followed by an increase in the finest particle size fraction (Dâ¯<â¯63⯵m). Maximum concentrations were 5, ND, 108, 23810, 83, ND, 77 and 150â¯mgâ¯kg-1 for Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn, respectively. The RDS enrichment ratio was Cr(1.3â¯×â¯), Cu(2.6â¯×â¯), Fe(3.3â¯×â¯), Mn(1.5â¯×â¯), Pb(1.5â¯×â¯) and Zn(2.1â¯×â¯). The Geo-accumulation Index values showed that RDS were moderately polluted for Cu and slighted polluted for Zn and Pb. Principal Component Analysis (PCA) showed that the accumulation of toxic heavy metals decreased according to water flow.
Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Emissões de Veículos/análise , Poluentes Químicos da Água/análise , Brasil , Tamanho da Partícula , Análise de Componente Principal , Estações do Ano , Espectrofotometria Atômica , Poluição Relacionada com o Tráfego/análise , Clima TropicalRESUMO
BACKGROUND: Deficits in ankle muscle strength and ankle stiffness may be present in those subjects who underwent surgical treatment for an Achilles tendon rupture. The presence of these long-term deficits may contribute to a lower performance during daily activities and may be linked to future injuries. OBJECTIVE: To compare the ankle passive stiffness and the plantar flexor muscle performance in patients who underwent unilateral surgical treatment of Achilles tendon rupture with nonsurgical subjects. METHOD: Twenty patients who underwent unilateral surgical treatment of Achilles tendon rupture [surgical (SU) group], and twenty nonsurgical subjects [non-surgical (NS) group] participated in this study. The ankle passive stiffness was evaluated using a clinical test. The concentric and eccentric plantar flexors performance (i.e. peak torque and work) was evaluated using an isokinetic dynamometer at 30°/s. RESULTS: The surgical ankle of the surgical group presented lower stiffness compared to the non-surgical ankle (mean difference=3.790; 95%CI=1.23-6.35) and to the non-dominant ankle of the non-surgical group (mean difference=-3.860; 95%CI=-7.38 to -0.33). The surgical group had greater absolute asymmetry of ankle stiffness (mean difference=-2.630; 95%CI=-4.61 to -0.65) and greater absolute asymmetry of concentric (mean difference=-8.3%; 95%CI=-13.79 to -2.81) and eccentric (mean difference=-6.9%; 95%CI=-12.1 to -1.7) plantar flexor work compared to non-surgical group. There was no other difference in stiffness and plantar flexor performance. CONCLUSION: Patients who underwent surgical repair of the Achilles tendon presented with long-term (1 year or more) deficits of ankle stiffness and asymmetries of ankle stiffness and plantar flexor work in the affected ankle compared to the uninjured side in the surgical group and both sides on the nonsurgical group.
Assuntos
Tendão do Calcâneo/fisiopatologia , Articulação do Tornozelo/fisiopatologia , Tornozelo/fisiopatologia , Força Muscular/fisiologia , Traumatismos dos Tendões/fisiopatologia , Estudos Transversais , HumanosRESUMO
Metformin is a hypoglycemiant drug prescribed for the treatment and control of the type 2 diabetes mellitus. Recently, the potential efficacy of this antidiabetic drug as an anticancer agent has been demonstrated in various mammalian cancer cells. This report evaluates the mutagenic as well as the recombinogenic potentials of the metformin drug in therapeutically relevant plasma concentrations (12.5 µM, 25.0 µM or 50.0 µM). Since the loss of heterozygosity is a process associated with carcinogenesis, the recombinogenic potential of such a drug was evaluated by the homozygotization assay using a heterozygous diploid strain of Aspergillus nidulans. The homozigotization indices (HI) for the genetic markers from the metformin-treated diploids were not statistically different from the negative control (non-treated diploids). For the first time, this indicated a lack of recombinogenic activity of the antidiabetic drug. The mutagenic potential of the metformin drug was evaluated by the chromosome aberrations and the micronuclei tests in human lymphocytes cultures. The metformin drug did not show any significant increase either in the numerical or in the structural chromosome aberrations and did not affect significantly the mitotic index when compared to the negative control. In the in vitro micronucleus test, the drug did not increase the number of micronuclei or nuclear buds when compared with the negative control. The data in this study suggest that the metformin drug is not a secondary cancer inducer, since it has neither showed recombinogenic nor mutagenic activities when used in pharmacological concentrations.
Assuntos
Metformina/toxicidade , Mutagênicos/toxicidade , Adulto , Aspergillus nidulans/citologia , Aspergillus nidulans/efeitos dos fármacos , Cromátides/metabolismo , Aberrações Cromossômicas/efeitos dos fármacos , Segregação de Cromossomos/efeitos dos fármacos , Cromossomos de Mamíferos/metabolismo , Diploide , Feminino , Haploidia , Heterozigoto , Homozigoto , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Testes para Micronúcleos , Índice Mitótico , Adulto JovemRESUMO
Studies show that genetic polymorphisms in apolipoproteins, which are in charge of lipid transport, predispose to atherogenic dyslipidemia. This study aimed to investigate the impact of apolipoprotein E, A5, and B genotypes and dietary intake on lipid profile in a sample of elderly women in Brazil. Two hundred and fifty-two women (60 years or older) living in the outskirts of the Brazilian Federal District underwent clinical and laboratory assessments to characterize glycemic and lipidemic variables, and also to exclude confounding factors (smoking, drinking, hormone replacement, cognitive impairment, physical activity). Three-day food records were used to determine usual dietary intake, whereas genotypic evaluations were in accordance to established methodologies. Genotype frequencies were consistent with the Hardy-Weinberg equilibrium. Prior to adjustment, individuals carrying the epsilon2 allele showed higher serum levels of triglycerides (P<0.05) and VLDL (P<0.005) compared to epsilon4 carriers, whereas LDL levels were considerably elevated in epsilon4 compared to epsilon2 carriers. In the presence of high intake of total fat or a low ratio of polyunsaturated to saturated fatty acid, epsilon4 carriers lost protection against hypertriglyceridemia. There was no association of the apolipoprotein A5 and B genotypes with lipidemic levels independently of the fat intake regimen. Results are suggestive of a dysbetalipoproteinemic-like phenotype in postmenopausal women, with remarkable gene-diet interaction.
Assuntos
Idoso , Apolipoproteínas/genética , Gorduras na Dieta/farmacologia , Lipoproteínas/sangue , Idoso de 80 Anos ou mais , Apolipoproteínas/fisiologia , Brasil , Análise Mutacional de DNA , Registros de Dieta , Inquéritos sobre Dietas , Ingestão de Alimentos/fisiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Primary sensory afferent neurons modulate the hyperdynamic circulation in cirrhotic rats with portal hypertension. The stomach of cirrhotic rats is prone to damage induced by ethanol, a phenomenon associated with reduced gastric hyperemic response to acid-back diffusion. The aim of this study was to examine the impact of ablation of capsaicin-sensitive neurons and the tachykinin NK(1) receptor antagonist A5330 on the susceptibility of the portal hypertensive gastric mucosa to ethanol-induced injury and its effects on gastric cyclooxygenase (COX) and nitric oxide synthase (NOS) mRNA expression. Capsaicin was administered to neonatal, male, Wistar rats and the animals were allowed to grow. Cirrhosis was then induced by bile duct ligation in adult rats while controls had sham operation. Ethanol-induced gastric damage was assessed using ex vivo gastric chamber experiments. Gastric blood flow was measured as well as COX/NOS mRNA expression. Topical application of ethanol produced significant gastric damage in cirrhotic rats compared to controls, which was reversed in capsaicin- and A5330-treated animals. Mean arterial and portal pressure was normalized in capsaicin-treated cirrhotic rats. Capsaicin and A5330 administration restored gastric blood flow responses to topical application of ethanol followed by acid in cirrhotic rats. Differential COX and NOS mRNA expression was noted in bile duct ligated rats relative to controls. Capsaicin treatment significantly modified gastric eNOS/iNOS/COX-2 mRNA expression in cirrhotic rats. Capsaicin-sensitive neurons modulate the susceptibility of the portal hypertensive gastric mucosa to injury induced by ethanol via tachykinin NK(1) receptors and signalling of prostaglandin and NO production/release.
Assuntos
Capsaicina/farmacologia , Etanol/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Hipertensão Portal/metabolismo , Cirrose Hepática Experimental/metabolismo , Neurônios Aferentes/efeitos dos fármacos , Receptores da Neurocinina-1/metabolismo , Animais , Animais Recém-Nascidos , Pressão Sanguínea/efeitos dos fármacos , Ducto Colédoco/cirurgia , Mucosa Gástrica/irrigação sanguínea , Mucosa Gástrica/enzimologia , Mucosa Gástrica/inervação , Mucosa Gástrica/patologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hipertensão Portal/patologia , Hipertensão Portal/fisiopatologia , Ligadura , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/fisiopatologia , Masculino , Antagonistas dos Receptores de Neurocinina-1 , Neurônios Aferentes/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Pressão na Veia Porta/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fluxo Sanguíneo Regional/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
Além de influenciar o crescimento corpóreo, o hormônio do crescimento, ou somatotrófico, desempenha importante papel no metabolismo, composição corporal, perfil lipídico, estado cardiovascular e longevidade. Seu controle é multi-regulado por hormônios, metabólitos e peptídeos hipotalâmicos. Dados sobre a Deficiência Isolada de GH (DIGH) obtidos a partir da descrição da mutação IVS1+1G®A no gene do receptor do hormônio liberador do GH (GHRH-R) em indivíduos da cidade de Itabaianinha, SE, são revisados. São abordadas novas perspectivas sobre o modelo de resistência ao GHRH, a importância do GHRH no controle da secreção de GH, a freqüência das mutações do gene do GHRH-R, a relevância diagnóstica do IGF-I e os achados metabólicos, cardiovasculares e de qualidade de vida nestes indivíduos.
Assuntos
Adolescente , Adulto , Criança , Humanos , Pessoa de Meia-Idade , Hormônio do Crescimento/deficiência , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Brasil , Hormônio Liberador de Hormônio do Crescimento/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , MutaçãoRESUMO
In addition to stimulating body growth, growth or somatotrophic hormone plays an important role in metabolism, body composition, lipid profile, cardiovascular status and longevity. Its control is multiregulated by hormones, metabolites and hypothalamic peptides. Obtained data of the isolated growth hormone deficiency (IGHD) after the description of the IVS1+1G-->A GHRH receptor gene mutation in individuals of Itabaianinha County are reviewed. New perspectives about the growth hormone resistance model, the importance of GHRH in the control of GH secretion, the frequency of GHRH-R gene mutations, the diagnostic relevance of IGF-I and the metabolic, cardiovascular and quality of life findings are approached.