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1.
Public Health ; 149: 49-56, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28551470

RESUMO

OBJECTIVE: Despite the harmful effects of cigarette smoking, this habit in asthmatic adolescents continues to be a health problem worldwide. Our objectives were to determine the epidemiological profile of smoking and the degree of nicotine dependence among asthmatic adolescents. STUDY DESIGN: Through a cross-sectional investigation, 3383 adolescents (13-19 years of age) were studied. METHODS: Information was collected using a previously validated questionnaire. Two study groups of adolescent smokers were formed: one composed of asthmatic adolescents and the other of healthy youths. RESULTS: Asthmatic adolescents were found to be more likely to smoke (21.6% vs 11.8%) and to have some degree of nicotine dependence compared with healthy adolescents (51.6% vs 48.8%). The most important characteristic of smoking in asthmatic adolescents was found to be an onset before 11 years of age due to curiosity about cigarettes. Asthmatic youths continue smoking because this habit decreases their anxiety and stress. Adolescents know that smoking is addictive and often smoke on waking up in the morning or when they are sick. Yet, these adolescents do not consider smoking to be a problem. CONCLUSION: In this study, curiosity about cigarettes was the primary reason why asthmatic adolescents smoked for the first time and developed a greater dependence to nicotine compared with healthy adolescents. Moreover, the findings show that many of the factors that favour the development of smoking are preventable, given that they are present in the family and social environment.


Assuntos
Asma/epidemiologia , Comportamento Aditivo , Fumar/epidemiologia , Tabagismo/epidemiologia , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Fumar/psicologia , Inquéritos e Questionários , Tabagismo/psicologia , Adulto Jovem
2.
Asian-Australas J Anim Sci ; 29(5): 666-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26954168

RESUMO

Two experiments were conducted to evaluate the effects of the level of corn dry distillers grains with solubles (CDDGS) supplementation on growing performance, blood metabolites, digestion characteristics and ruminal fermentation patterns in steers grazing dormant forage. In Exp. 1, of growth performance, 120 steers (204±5 kg initial body weight [BW]) were distributed randomly into 3 groups (each of 40 steers), which were provided with the following levels of CDDGS supplement: 0%, 0.25%, or 0.50% BW. All groups of steers were grazed for 30 days in each of 3 grazing periods (March, April, and May). Approximately 1,000 ha of the land was divided with electric fencing into 3 equally sized pastures (333 ha in size). Blood samples were collected monthly from 20 steers in each grazing group for analysis of glucose (G), urea-nitrogen (UN) and non-esterified fatty acids. Final BW, average daily gain (ADG) and supplement conversion (CDDGS-C) increased with increasing levels of CDDGS supplementation (p<0.05).The CDDGS supplementation also increased the plasma G and UN concentrations (p<0.05). In Exp. 2, of digestive metabolism, 9 ruminally cannulated steers (BW = 350±3 kg) were distributed, following a completely randomized design, into groups of three in each pasture. The ruminally cannulated steers were provided the same levels of CDDGS supplementation as in the growing performance study (0%, 0.25%, and 0.50% BW), and they grazed along with the other 40 steers throughout the grazing periods. The dry matter intake, crude protein intake, neutral detergent fiber intake (NDFI), apparent digestibility of dry matter (ADDM), crude protein (ADCP) and neutral detergent fiber (ADNDF) increased with increasing levels of CDDGS supplementation (p<0.05). The ruminal degradation rates of CP (kdCP), NDF (kdNDF) and passage rate (kp) also increased with increasing levels of CDDGS supplementation (p<0.05). Ruminal ammonia nitrogen (NH3-N) and propionate concentrations also increased with increasing levels of CDDGS supplementation (p<0.05). However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05). Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05). On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns.

3.
Plant Dis ; 98(7): 1018, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30708902

RESUMO

Seashore paspalum (Paspalum vaginatum Swartz) is a warm-season perennial turfgrass commonly used for golf courses that are grown in saline environments or using saline water for irrigation. However, seashore paspalum is also grown in non-saline conditions due to its low fertilizer and water requirements (2). In Barbados, on a newly constructed golf course, seashore paspalum 'Sea Isle Supreme' sprigs were imported from Georgia (United States) and were planted over 2006 and 2007 on greens, tees, fairways, and rough. Golf greens were constructed following the United States Golf Association Green Section (Far Hills, NJ) putting green guidelines. Tees and fairways were constructed using native soil. Two years after the grow-in, the putting greens began to exhibit irregular chlorotic patches, followed by gradual thinning and decline of turfgrass stand density in those areas. Additionally, turfgrass roots sampled from those symptomatic patches appeared to be abbreviated compared to non-symptomatic areas of the greens. A survey was conducted in May 2013 to determine if plant-parasitic nematodes were present coinciding with the observed symptoms, which were similar to those described in a previous report (3). Consequently, two samples were collected from each green with a total of four greens sampled. Each sample consisted of 20 soil cores (15 cm depth × 1.2 cm in diameter) from either areas of the greens showing symptoms or from non-symptomatic areas. Nematodes were extracted from 100 cm3 soil samples using a modified centrifugal-sugar flotation technique (4). No plant parasitic nematodes were present in any of the samples from the non-symptomatic areas. Three genera of plant parasitic nematodes were found in all the samples from the symptomatic areas: Helicotylenchus. Mesocriconema, and Pratylenchus. Nematode populations of these genera averaged 30, 60, and 200 nematodes per 100 cm3, respectively. Populations of the genera Helicotylenchus and Mesocriconema were below the action threshold levels for seashore paspalum used by the University of Florida Nematode Assay Laboratory (1). Currently, no threshold exists for Pratylenchus for seashore paspalum. Conversely, the genera Helicotylenchus. Mesocriconema, and Pratylenchus were found associated with the irregular chlorotic patches but not with the non-symptomatic areas. To our knowledge, this is the first report of plant parasitic nematodes associated with seashore paspalum maintained as putting greens in Barbados. References: (1) W. T. Crow. Nematode management for golf courses in Florida. EDIS. Accessed 31 July 2013 from: http://edis.ifas.ufl.edu/in124 , 2001. (2) R. R. Duncan and R. N. Carrow. Seashore Paspalum: The Environmental Turfgrass. John Wiley & Sons, Inc., Hoboken, New Jersey, 2000. (3) A. C. Hixson and W. T. Crow. Plant Dis. 88:680, 2004. (4) W. R. Jenkins. Plant Dis. Rep. 48:692, 1964.

4.
Plant Biol (Stuttg) ; 26(2): 245-256, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38196283

RESUMO

This study was designed to elucidate the physiological responses of three Lotus forage accessions to alkaline stress, and the influence of inoculating with Pantoea eucalypti endophyte strain on alkaline stress mitigation. A diploid L. corniculatus (Lc) accession, L. tenuis (Lt), and the interspecific hybrid Lt × Lc obtained from these two parental lines were exposed to alkaline stress (pH 8.2). Both Lt and the Lt × Lc hybrid are alkaline-tolerant compared to Lc, based on observations that dry mass was not reduced under stress, and there were no chlorosis symptoms on leaf blades. In all three Lotus accessions, Fe2+ concentration under stress decreased in aerial parts and simultaneously increased in roots. Inoculation with P. eucalypti considerably increased Fe2+ content in shoots of all three Lotus forage species under alkaline treatment. Photochemical efficiency of PSII was affected in Lc accession only when exposed to alkaline treatment. However, when cultivated under alkalinity with inoculation, plants recovered and had photosynthetic parameters equivalent to those in the control treatment. Together, the results highlight the importance of inoculation with P. eucalypti, which contributes significantly to mitigating alkaline stress. All results provide useful information for improving alkaline tolerance traits of Lotus forage species and their interspecific hybrids.


Assuntos
Lotus , Pantoea , Lotus/fisiologia , Hibridização Genética , Fotossíntese
5.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(2): 83-97, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36068132

RESUMO

OBJECTIVE: To identify the ocular pathologies that are reported as causes of low vision in children. MATERIAL AND METHODS: The systematic search was carried out in Medline (PubMed), Embase and Lilacs. Observational studies with populations between 0-18 years of age, reporting visual acuity data between 20/60-20/400 and reporting the frequency of ocular pathologies were selected. Studies in which the diagnosis of the condition had not been verified by a professional, or which covered only cases of blindness, uncorrected refractive errors, or amblyopia, were excluded. The methodological quality of the articles was evaluated using the Joanna Briggs Institute instrument for prevalence studies. RESULTS: 27 studies conducted in Asia (13 publications), Africa (6 studies), Oceania (4 studies), Europe and South America (2 studies each) were included. The most reported causes of low vision were: cataract, with prevalence between 0.8% and 27.2%; albinism with from 1.1% to 47%; nystagmus, with prevalence between 1.3% and 22%; retinal dystrophies between 3.5% and 50%; retinopathy of prematurity (ROP) with prevalence between 1.1% and 65.8%, optic atrophy between 0.2% and 17.6%, and glaucoma from 2.4% to 18.1%. CONCLUSIONS: Cataract, albinism and nystagmus are the ocular pathologies most mentioned by studies as a cause of low vision in children, as well as retinal diseases such as ROP and optic nerve diseases such as atrophy. However, there are numerous eye conditions that can result in low vision in the pediatric population.


Assuntos
Catarata , Glaucoma , Nistagmo Patológico , Retinopatia da Prematuridade , Baixa Visão , Recém-Nascido , Humanos , Criança , Baixa Visão/etiologia , Baixa Visão/complicações , Cegueira/etiologia , Glaucoma/complicações , Catarata/complicações , Retinopatia da Prematuridade/complicações
6.
Asian-Australas J Anim Sci ; 25(10): 1395-403, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25049495

RESUMO

The objective of the study was to quantify annual and seasonal differences in the chemical composition, in vitro gas production, in situ degradability and ruminal fermentation of grazing steers' diets. Diet samples were collected with four esophageal cannulated steers (350±3 kg BW); and four ruminally cannulated heifers (342±1.5 kg BW) were used to study the dry matter degradation and fermentation in rumen. Data were analyzed with repeated measurements split plot design. The crude protein, in vitro dry matter digestibility and metabolizable energy were higher during the first year of trial and in the summer (p<0.01). The values of calcium, phosphorus, magnesium, zinc and copper were higher in summer (p<0.05). The gas produced by the soluble and insoluble fractions, as well as the constant rate of gas production were greater in summer and fall (p<0.01). The ammonia nitrogen (NH3N) and total volatile fatty acids concentrations in rumen, the soluble and degradable fractions, the constant rate of degradation and the effective degradability of DM and NDF were affected by year (p<0.05) and season (p<0.01). Our study provides new and useful knowledge for the formulation of protein, energetic and mineral supplements that grazing cattle need to improve their productive and reproductive performance.

7.
J Appl Microbiol ; 110(5): 1151-65, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21299771

RESUMO

AIMS: To isolate and characterize phosphate-solubilizing strains from a constrained environment such as the Salado River Basin and to assess their phosphate-solubilizing mechanisms, to further selection of the most promising strains to inoculate and improve the implantation and persistence of Lotus tenuis in the most important area devoted to meat-cow production in Argentina. METHODS AND RESULTS: Fifty isolates were obtained and through BOX-PCR analysis, 17 non-redundant strains were identified. Subsequently, they were found to be related to Pantoea, Erwinia, Pseudomonas, Rhizobium and Enterobacter genera, via 16S rRNA gene sequence analysis. This was in agreement with the clusters obtained by antibiotic resistance analysis. All isolates were tested for their phosphate-solubilizing activity and selected strains were inoculated onto L. tenuis plants. The most efficient isolate, was identified as Pantoea eucalypti, a novel species in terms of plant growth-promoting rhizobacteria. CONCLUSIONS: The isolates obtained in this study showed a significant in vitro plant-growth promoting activity onto Lotus tenuis and the best of them solubilizes phosphate mainly via induction of the metabolism through secretion and oxidation of gluconic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of these bacteria as bioinoculants, alone or in combination with nitrogen-fixing micro-organisms, could be a sustainable practice to facilitate the nutrient supply to Lotus tenuis plants and preventing negative side-effects such as eutrophication.


Assuntos
Lotus/crescimento & desenvolvimento , Lotus/microbiologia , Pantoea/fisiologia , Fosfatos/metabolismo , Rizosfera , Microbiologia do Solo , Argentina , Desidrogenases de Carboidrato/metabolismo , Enterobacter/genética , Erwinia/genética , Eucalyptus/metabolismo , Gluconatos/metabolismo , Glucose Desidrogenase/metabolismo , Oxirredução , Pantoea/genética , Pantoea/isolamento & purificação , Filogenia , Pseudomonas/genética , RNA Ribossômico 16S/genética , Rhizobium/genética , Rios
8.
Plant Biol (Stuttg) ; 23(2): 363-374, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33190297

RESUMO

Waterlogging and salinity impair crop growth and productivity worldwide, with their combined effects being larger than the additive effects of the two stresses separately. Here, a common forage tetraploid Lotus corniculatus (cv. San Gabriel) and a diploid L. corniculatus accession, collected from a coastal area with high frequency of waterlogging-saline stress events, were evaluated for tolerance to waterlogging, salinity and these two stresses combined. We hypothesize that, due to its environmental niche, the diploid accession would show better adaptation to combined waterlogging-saline stress compared to the tetraploid L. corniculatus. Plants were evaluated under control conditions, waterlogging, salinity and a combined waterlogging-saline treatment for 33 days. Shoot and root growth were assessed, together with chlorophyll fluorescence and gas exchange measurements. Results showed that salinity and waterlogging effects were more severe for the tetraploid accession, with a larger effect being observed under the combined stress condition. Concentrations of Na+ , Cl- and K+ were measured in apical and basal leaves, and in roots. A larger accumulation of Na+ and Cl- was observed under both saline and combined stress treatments for the tetraploid L. corniculatus, for which ion toxicity effects were evident. The expression of CLC gene, coding for a Cl- transporter, was only increased in diploid L. corniculatus plants in response to the combined stress condition, suggesting that ion compartmentalization mechanisms were induced in this accession. Thus, this recently characterized L. corniculatus could be used for the introduction of new tolerance traits in other Lotus species used as forage.


Assuntos
Lotus , Cloreto de Sódio , Estresse Fisiológico , Lotus/efeitos dos fármacos , Lotus/genética , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Salinidade , Cloreto de Sódio/toxicidade , Estresse Fisiológico/genética , Água/farmacologia
9.
Rev Esp Anestesiol Reanim ; 57(1): 61-4, 2010 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-20196522

RESUMO

The McGrath video laryngoscope is a new airway management device. It is similar to the Macintosh laryngoscope but incorporates a blade at a 60 degrees angle and a camera that sends an image to a color display screen connected to the handle. The device, which requires use of an anti-fog substance and an introducer to guide the angled blade, has been reported to aid in the management of difficult airways. We present 3 cases of difficult oral-tracheal intubation managed with the McGrath video laryngoscope and a Frova intubating introducer. Advantages of this introducer are that it offers the possibility of administering oxygen or changing the size of the endotracheal tube if the first choice proves inappropriate. We discuss whether or not tests to predict difficult airways are applicable when the McGrath video laryngoscope is being used, given that it is not necessary to align the axes of the 3 airways. We conclude it may be useful to combine the McGrath video laryngoscope and the Frova introducer to manage difficult airways.


Assuntos
Obstrução das Vias Respiratórias , Intubação Intratraqueal/métodos , Laringoscópios , Gravação em Vídeo/instrumentação , Parede Abdominal/cirurgia , Vértebras Cervicais/cirurgia , Comorbidade , Discotomia , Desenho de Equipamento , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Masculino , Pessoa de Meia-Idade , Oxigenoterapia/instrumentação , Nódulo da Glândula Tireoide/cirurgia , Tireoidectomia
11.
Arch Soc Esp Oftalmol ; 83(9): 545-8, 2008 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-18803127

RESUMO

PURPOSE: To present a case of long term central serous corioretinopathy associated with chronic detachment of the retinal pigment epithelium (RPE) and the effect of photodynamic therapy on it. CASE CLINIC: We present the case of a 46-year old man with long term chronic central serous chorioretinopathy (18 mo.) with chronic detachment of RPE in his left eye who underwent PDT with Verteporfin (Visudyne). BCVA improved from 0.7 to 1 and metamorphopsia disappeared within one month of treatment. The patient remained asymptomatic for a follow-up period of 15 months. DISCUSSION: Choroidal hyperpermeability is found in central serous chorioretinopathy as a primary involvement factor. PDT with Verteporfin induces a transient reduction in choriocapilaris blood flow and can be used as treatment in cases of chronic central serous chorioretinopathy.


Assuntos
Doenças da Coroide/complicações , Fotoquimioterapia , Descolamento Retiniano/tratamento farmacológico , Descolamento Retiniano/etiologia , Doenças Retinianas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Obes Surg ; 17(3): 348-54, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17546843

RESUMO

BACKGROUND: Scopinaro biliopancreatic diversion (BPD) is associated with malabsorption of calcium and vitamin D, which manifests as a secondary hyperparathyroidism (SHP) and may lead to osteopenia. METHODS: 96 morbidly obese patients were studied (age 19-60 years, 23 men and 73 women, with mean initial BMI 53) following intervention by Scopinaro BPD. The change in iPTH levels, urine DPD, Pyrilinks-D of DPC and serum CTx were studied at 0, 3, 6, 12, 18 and 24 months after surgery. Postoperatively, they were given supplements of calcium and vitamin D3. The control group consisted of 67 non-obese women and 10 men. RESULTS: The iPTH levels gradually increased after BPD, with a substantial difference compared to presurgery levels at month 6. In spite of the calcium and vitamin D supplements, 77% of the patients with presurgery SHP did maintain high levels of iPTH after 2 years. The percentage of SHP among the patients with normal pre-surgery iPTH was 58%. The basal figures of DPD/cre were significantly higher than in the control group, 9.06 (4.6-13.5) nM/mMcre vs 3.9 (2.8-5.6) in men and 6.75 (5.4-7.9) vs 7.67 (3.3-11.6) in women, but not CTx, 0.24 (0.02-0.89) vs 0.22 (0.07-0.55). After the operation, there was a noticeable increase which persisted at 2 years. There was a lack of correlation between the levels of iPTH and the bone resorption markers, i.e. the first ones decreased from month 6 in men and from month 12 in women, while the levels of iPTH continued to increase. CONCLUSION: In obese patients, we found no correlation between iPTH levels and BMI. Supplements of calcium and vitamin D did not prevent the appearance of SHP following BPD. The patients with high pre-surgery iPTH levels have a higher risk of malabsorption of calcium and vitamin D. Following malabsorptive bariatric surgery, there is an increase in bone resorption, which results in DPD and CTx increase. Those markers do not correlate with iPTH, and this may suggest that there is a phenomenon of bone reshaping parallel to the loss of weight.


Assuntos
Desvio Biliopancreático , Obesidade Mórbida/sangue , Hormônio Paratireóideo/sangue , Adulto , Calcifediol/sangue , Cálcio/urina , Colágeno/sangue , Creatinina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia
13.
Plant Biol (Stuttg) ; 18(4): 703-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27007305

RESUMO

A common stress on plants is NaCl-derived soil salinity. Genus Lotus comprises model and economically important species, which have been studied regarding physiological responses to salinity. Leaf area ratio (LAR), root length ratio (RLR) and their components, specific leaf area (SLA) and leaf mass fraction (LMF) and specific root length (SRL) and root mass fraction (RMF) might be affected by high soil salinity. We characterised L. tenuis, L. corniculatus, L. filicaulis, L. creticus, L. burtii and L. japonicus grown under different salt concentrations (0, 50, 100 and 150 mm NaCl) on the basis of SLA, LMF, SRL and RMF using PCA. We also assessed effects of different salt concentrations on LAR and RLR in each species, and explored whether changes in these traits provide fitness benefit. Salinity (150 mm NaCl) increased LAR in L. burtii and L. corniculatus, but not in the remaining species. The highest salt concentration caused a decrease of RLR in L. japonicus Gifu, but not in the remaining species. Changes in LAR and RLR would not be adaptive, according to adaptiveness analysis, with the exception of SLA changes in L. corniculatus. PCA revealed that under favourable conditions plants optimise surfaces for light and nutrient acquisition (SLA and SRL), whereas at higher salt concentrations they favour carbon allocation to leaves and roots (LMF and RMF) in detriment to their surfaces. PCA also showed that L. creticus subjected to saline treatment was distinguished from the remaining Lotus species. We suggest that augmented carbon partitioning to leaves and roots could constitute a salt-alleviating mechanism through toxic ion dilution.


Assuntos
Lotus/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Biomassa , Carbono/metabolismo , Luz , Lotus/fisiologia , Lotus/efeitos da radiação , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Raízes de Plantas/efeitos da radiação , Caules de Planta/efeitos dos fármacos , Caules de Planta/fisiologia , Caules de Planta/efeitos da radiação , Salinidade , Tolerância ao Sal , Solo/química , Estresse Fisiológico
15.
Biochim Biophys Acta ; 954(1): 114-25, 1988 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-3282545

RESUMO

The inhibitory effect of a series of 2-alkylputrescines on rat liver and Escherichia coli ornithine decarboxylase (L-ornithine carboxy-lyase, EC 4.1.1.17) was examined. At 2.5 mM concentrations, 2-methyl-, 2-propyl-, 2-butyl-, 2-pentyl- and 2-hexylputrescines were stronger inhibitors of the mammalian enzyme than putrescine. Only the higher homologues (from 2-propyl- to 2-hexylputrescine) were inhibitors of the E. coli enzyme. An analysis of the effect of increasing concentrations of the 2-alkylputrescines showed that the main difference in the behaviour of the mammalian and E. coli decarboxylases toward 2-alkylputrescines was that the former was strongly inhibited by 2-methylputrescine whereas the latter was not. 2-Alkylputrescines were found to be competitive inhibitors of both the bacterial and mammalian enzyme. The smallest Ki values (0.1 and 0.5 mM) were found for the 2-hexyl- and 2-pentylputresciens. N-Methyl-, N-ethyl-, N-propyl- and N-butylputrescines (50 mumol per 100 g body weight) were assayed as inhibitors of thioacetamide-induced rat liver ornithine decarboxylase. N-Propylputrescine was found to be the most inhibitory (66% inhibition) and although the N-alkylputrescines were taken up by the liver, they did not inhibit the liver polyamine pools. Both putrescine and N-methylputrescine were found to stabilize the thioacetamide-induced ornithine decarboxylase at the onset of the enzyme's degradation, while 2-alkylputrescines were inhibitory under similar conditions. N-Methylputrescine induced antizyme in thioacetamide-treated rats. In thioacetamide- or dexamethasone-treated rats, 2-methylputrescine was found to be the strongest in vivo inhibitor of the liver decarboxylase. Although 2-alkylputrescines were efficiently taken up by the liver, they did not noticeably inhibit its polyamine pools. 2-methylputrescine decreased the putrescine concentration of the liver, but not its spermidine and spermine content. No induction of ornithine decarboxylase antizyme by 2-methylputrescine could be detected. The intrahepatic concentration of the latter decreased with time, very likely due to its degradation by a diamine oxidase, since the decrease was inhibited by aminoguanidine.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Escherichia coli/enzimologia , Fígado/enzimologia , Inibidores da Ornitina Descarboxilase , Putrescina/farmacologia , Animais , Poliaminas/análise , Putrescina/análogos & derivados , Ratos , Relação Estrutura-Atividade
16.
Biochim Biophys Acta ; 873(1): 53-61, 1986 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-3527275

RESUMO

N-Methyl-, N-ethyl-, N-propyl-, N-butyl-, N,N-dimethyl- and N,N'-dimethylputrescines were assayed as inhibitors of ornithine decarboxylase (EC 4.1.1.17) from rat liver and from Escherichia coli. They were found to be poor inhibitors, with the exception of N-propylputrescine and N,N-dimethylputrescine, which were inhibitory at 25 mM. A homologous series of 1-alkylputrescines ranging from 1-methylputrescine (1,4-diaminopentane) to 1-heptylputrescine (1,4-diaminoundecane) was assayed for effect on the activity of ornithine decarboxylase from the same sources. 1-Methylputrescine (5 mM) inhibited the mammalian enzyme, while the higher homologues showed significantly less inhibitory activity. When assayed on the bacterial enzyme, 1-methylputrescine (5 mM) was not inhibitory, while the higher homologues showed inhibitory effects. At higher concentrations, 1-methylputrescine and 1-heptylputrescine were the best inhibitors of these series of rat liver ornithine decarboxylase. When 1-methylputrescine, 2-methylputrescine, 1,2-dimethylputrescine, 1,3-dimethylputrescine and 1,4-dimethylputrescine were assayed as inhibitors of the decarboxylase, 2-methylputrescine was found to be the best inhibitor of the rat liver enzyme, while 1,3-dimethylputrescine was the best inhibitor of the bacterial enzyme. 1,4-Dimethylputrescine (2,5-diaminohexane) did not inhibit the enzyme from either source. Both, 2-methylputrescine and 1-methylputrescine, as well as the 1,2- and 1,3-dimethylputrescines were competitive inhibitors of the enzyme, and a Ki of 1 mM was obtained for 2-methylputrescine when the rat liver decarboxylase was used. N-Methyl, 1-methyl and 2-methylputrescines were found to inhibit in vivo the activity of rat liver ornithine decarboxylase which had been previously induced by thioacetamide treatment. 2-Methylputrescine (50 mumol/100 g body weight) was found to be the best in vivo inhibitor (93% inhibition), while putrescine under similar conditions inhibited 56% of the enzymatic activity.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Escherichia coli/enzimologia , Fígado/enzimologia , Inibidores da Ornitina Descarboxilase , Putrescina/análogos & derivados , Animais , Putrescina/farmacologia , Ratos , Especificidade da Espécie , Relação Estrutura-Atividade
17.
Biochim Biophys Acta ; 1237(1): 16-22, 1995 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-7619837

RESUMO

Renal brush border membranes contain several anion exchanges that may play a role in electrolyte transport and pH regulation. To help characterize the types of exchangers present and the binding properties of these membranes, the binding of nitrate (NO3-) to highly purified rabbit kidney brush border membrane vesicles was studied. The method is based on the binding induced quadrupole relaxation of the 14N-NMR signal of nitrate [1,2]. Brush border membrane vesicles caused a relaxation of the 14N-NMR nitrate signal which could be characterized by relatively high affinity sites, KD = 6.7 +/- 1.5 mM, as well as nonspecific interactions with the membranes, KD > 150 mM. The anion transport inhibitor 4,4'-dinitrostilbene-2,2'-disulfonate (DNDS) inhibited 51 +/- 6% (n = 4) of the relaxation due to the high affinity binding sites. The DNDS inhibition could be characterized by a Ki of 10-80 microM. Both bicarbonate and formate (HCO2-) were found to partially inhibit the high affinity induced relaxation, with maximal inhibition of 37 +/- 8% (n = 3) and 30 +/- 2% (n = 3), respectively. The inhibitory effects of saturating concentrations of bicarbonate and formate were non-additive, suggesting the existence of a stilbene sensitive exchanger that can bind nitrate, as well as both bicarbonate and formate. This study indicates the usefulness of this new method for further investigation of anion exchangers on these and other membranes.


Assuntos
Rim/metabolismo , Nitratos/metabolismo , Animais , Bicarbonatos , Sítios de Ligação , Anidrases Carbônicas , Formiatos , Rim/ultraestrutura , Espectroscopia de Ressonância Magnética , Microvilosidades/metabolismo , Isótopos de Nitrogênio , Coelhos , Estilbenos
18.
Rev Calid Asist ; 30(4): 166-74, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26025386

RESUMO

OBJECTIVES: To identify and characterize adverse events (AE) in an Internal Medicine Department of a district hospital using an extension of the Global Trigger Tool (GTT), analyzing the diagnostic validity of the tool. METHODS: An observational, analytical, descriptive and retrospective study was conducted on 2013 clinical charts from an Internal Medicine Department in order to detect EA through the identification of 'triggers' (an event often related to an AE). The 'triggers' and AE were located by systematic review of clinical documentation. The AE were characterized after they were identified. RESULTS: A total of 149 AE were detected in 291 clinical charts during 2013, of which 75.3% were detected directly by the tool, while the rest were not associated with a trigger. The percentage of charts that had at least one AE was 35.4%. The most frequent AE found was pressure ulcer (12%), followed by delirium, constipation, nosocomial respiratory infection and altered level of consciousness by drugs. Almost half (47.6%) of the AE were related to drug use, and 32.2% of all AE were considered preventable. The tool demonstrated a sensitivity of 91.3% (95%CI: 88.9-93.2) and a specificity of 32.5% (95%CI: 29.9-35.1). It had a positive predictive value of 42.5% (95%CI: 40.1-45.1) and a negative predictive value of 87.1% (95%CI: 83.8-89.9). CONCLUSIONS: The tool used in this study is valid, useful and reproducible for the detection of AE. It also serves to determine rates of injury and to observe their progression over time. A high frequency of both AE and preventable events were observed in this study.


Assuntos
Gestão de Riscos/organização & administração , Adulto , Transtornos da Consciência/induzido quimicamente , Transtornos da Consciência/epidemiologia , Constipação Intestinal/epidemiologia , Infecção Hospitalar/epidemiologia , Delírio/epidemiologia , Departamentos Hospitalares/organização & administração , Hospitais de Distrito/organização & administração , Humanos , Medicina Interna/organização & administração , Erros Médicos , Erros de Medicação , Valor Preditivo dos Testes , Úlcera por Pressão/epidemiologia , Estudos Retrospectivos , Estudos de Amostragem , Sensibilidade e Especificidade
20.
FEBS Lett ; 219(2): 380-6, 1987 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-3111885

RESUMO

N-Methyl-, N-ethyl-, N-propyl- and N-butylputrescine were assayed as substrates of diamine oxidase from pea seedling and pig kidney. With the exception of N-methylputrescine they were found to be oxidized to the corresponding aminoaldehydes. 1-Methyl-, 2-methyl-, 1-ethyl- and 1-propylputrescine were oxidized by the oxidases at lower rates than the N-alkylderivatives. 1,3-Dimethylputrescine had negligible oxidation rates while 1,4-dimethylputrescine (2,5-diaminohexane) was not a substrate. The oxidation of putrescine by the kidney oxidase was inhibited by 1,4-dimethylputrescine, while the pea oxidase was strongly inhibited by the former as well as by 2-methylputrescine and 1,3-dimethylputrescine. Serum amine oxidase did not oxidize the substituted putrescines although several of the latter inhibited spermidine oxidation by this oxidase.


Assuntos
Amina Oxidase (contendo Cobre)/metabolismo , Putrescina/análogos & derivados , Alquilação , Animais , Rim/enzimologia , Cinética , Oxirredução , Plantas/enzimologia , Putrescina/metabolismo , Especificidade por Substrato , Suínos
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