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2.
Scand J Rheumatol ; 45(6): 480-490, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27218482

RESUMO

OBJECTIVES: To compare bone turnover marker (BTM) levels and bone mineral density (BMD) between patients with ankylosing spondylitis (AS) and healthy controls (HC) and to evaluate, in AS, the association between BTM levels and clinical variables, spinal syndesmophytes, and BMD using multivariate analysis. METHOD: Seventy-eight AS patients were compared with 58 HC matched by gender. Spinal syndesmophytes in AS and other characteristics were assessed. C-terminal telopeptide fragments of type I collagen (CTX), bone-specific alkaline phosphatase (BAP), osteocalcin (OC) serum levels, and BMD of the lumbar spine, femoral neck, and forearm were evaluated. RESULTS: AS males and females had lower BAP levels than their respective HC (p < 0.001 and p = 0.001). AS patients with bridging syndesmophytes had higher OC levels than AS patients either with non-bridging syndesmophytes (p = 0.001) or without spinal syndesmophytes (p < 0.001). OC and CTX levels correlated significantly with the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). In the multivariate linear regression adjusted by age, gender, the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), BMD in the lumbar spine, and C-reactive protein (CRP), we observed an association between BAP levels and anti-tumour necrosis factor (anti-TNF) use (p = 0.05) whereas OC levels were associated with mSASSS (p < 0.001) and anti-TNF use (p = 0.05), and CTX levels were exclusively associated with mSASSS (p = 0.03). In the logistic regression analysis, only OC levels were associated with the presence of syndesmophytes in AS [odds ratio (OR) 2.42, 95% confidence interval (CI) 1.19-5.75]. CONCLUSIONS: We observed an increase in OC levels in AS patients with syndesmophytes. BTM levels were associated with the severity of spinal damage. Future longitudinal studies should evaluate whether these BTMs should be included as tools to determine the prognosis and progression of spinal damage.


Assuntos
Densidade Óssea , Remodelação Óssea , Vértebras Cervicais/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Espondilite Anquilosante/fisiopatologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Espondilite Anquilosante/sangue , Espondilite Anquilosante/diagnóstico por imagem , Adulto Jovem
3.
Genet Mol Res ; 14(3): 11222-34, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26400353

RESUMO

A time-course feeding trial was conducted for 120 days on juvenile channel catfish (Ictalurus punctatus) to study the effects of diets differing in oil source (fish oil or soy oil) and supplementation with a commercial probiotic. Relative levels of Δ6-fatty acid desaturase (Δ6-FAD) and fatty acid elongase (FAE) expression were assessed in brain and liver tissues. Both genes showed similar expression levels in all groups studied. Fish weight-to-length relationships were evaluated using polynomial regression analyses, which identified a burst in weight and length in the channel catfish on day 105 of treatment; this increase was related to an increase in gene expression. Mid-intestinal lactic acid bacterium (LAB) count was determined according to morphological and biochemical criteria using API strips. There was no indication that intestinal LAB count was affected by the modified diets. The Cunningham glass adherence method was applied to evaluate phagocytic cell activity in peripheral blood. Reactive oxygen species (ROS) generation was assessed through the respiratory burst activity of spleen macrophages by the NBT reduction test. Probiotic-supplemented diets provided a good substrate for innate immune system function; the phagocytic index was significantly enhanced in fish fed soy oil and the probiotic, and at the end of the experimental period, ROS production increased in fish fed soy oil. The substitution of fish oil by soy oil is recommended for food formulation and will contribute to promoting sustainable aquaculture. Probiotics are also recommended for channel catfish farming as they may act as immunonutrients.


Assuntos
Acetiltransferases/metabolismo , Proteínas de Peixes/metabolismo , Ictaluridae/metabolismo , Linoleoil-CoA Desaturase/metabolismo , Acetiltransferases/genética , Ração Animal , Animais , Aquicultura , Peso Corporal , Encéfalo/enzimologia , Dieta , Elongases de Ácidos Graxos , Proteínas de Peixes/genética , Microbioma Gastrointestinal , Expressão Gênica , Ictaluridae/genética , Ictaluridae/crescimento & desenvolvimento , Linoleoil-CoA Desaturase/genética , Fígado/enzimologia , Macrófagos/fisiologia , Fagocitose , Probióticos/administração & dosagem , Explosão Respiratória , Óleo de Soja/administração & dosagem
4.
Poult Sci ; 94(2): 156-61, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25589080

RESUMO

To adapt commercial poultry production to a new scenario of energy savings and to develop specific practices for quail production aimed at reducing costs while maintaining or improving productivity, four experiments were conducted. In the first experiment, birds were allocated to four treatments (photoperiod duration): T1: 14 L:10 D; T2: 15 L:9 D; T3: 16 L:8 D; and T4: 17 L:7 D. In the second experiment, birds were subjected to four levels of brightness: T1: 5 lux; T2: 10 lux; T3:15 lux; and T4: 22 lux (control). In the third experiment, four types of lamps were evaluated: T1: compact fluorescent lamp (color temperature: 6,500 K); T2: compact fluorescent lamp (color temperature: 2,700 K); T3: incandescent lamp; and T4: yellow LED. In the last experiment, four lighting programs were compared: T1: continuous program (control), in which there was a single photoperiod of 15 h; the other treatments consisted of intermittent lighting programs, as follows: T2: 1 h of light provided 1 h after dusk; T3: 1 h of light provided 2 h before dawn; T4: half an hour of light provided 1 h after dusk and half an hour of light provided 1.5 h before dawn. In each experiment, 1,296 Japanese quail were evaluated for four 28-d cycles, totaling 112 experimental days. A completely randomized experimental design of 4 treatments with 12 replicates of 27 birds each was applied in all trials. Performance and egg quality were evaluated in each experiment. Higher egg production and adequate egg quality, as well as energy savings, can be obtained with Japanese quail using compact fluorescent lamps or LEDs and a photoperiod of 15 h/d supplied using an intermittent lighting program, with 1 h of artificial light 2 h before dawn at a brightness of 5 lux.


Assuntos
Coturnix , Abrigo para Animais , Luz , Fotoperíodo , Animais , Fatores de Tempo
5.
Poult Sci ; 93(7): 1855-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24812241

RESUMO

A study was conducted to investigate the effects of organic acids (OA) and competitive exclusion product (CE) on growth performance, intestinal morphology, and concentration of volatile fatty acids in the cecal content. The experiment lasted for 10 wk. Four hundred twenty 1-d-old female commercial cross turkey poults (British United Turkeys, BUT Big 9) were distributed into 4 treatments with 5 replicates/pen of 21 birds each. The birds were fed a basal diet without growth promoter (control), diet with lincomycin (44 mg/kg), diet with organic acids (2 g/kg), and diet with product of CE (10(9) cfu/kg). Dietary levels of other nutrients, housing, and general management practices were similar for all treatments. On the first week (d 0-7), the BW and BW gain of the birds that fed diets with OA were lower than in the control group. In the fattening phase (d 28-70), the feed intake of the OA-treated group was lower than compared with the control. The birds that received diet with OA and CE product presented higher concentrations of propionic acid, at 14 d, and butyric acid in cecal content at 28, 56, and 70 d, compared with the control. Dietary inclusion of additives had no significant effects on intestinal villus height, crypt depth, and villus:crypt ratio. Organic acids had negative effects either on early gain or feed intake throughout the study. Because the test was conducted under controlled experimental conditions, the additives that showed results similar to those found by using antibiotics should be studied further in commercial farms to obtain results that can be incorporated into practice.


Assuntos
Ácidos/farmacologia , Dieta/veterinária , Intestinos/efeitos dos fármacos , Perus/fisiologia , Ração Animal/análise , Animais , Ceco/química , Suplementos Nutricionais , Ácidos Graxos Voláteis/análise , Feminino , Conteúdo Gastrointestinal/química , Mucosa Intestinal/metabolismo , Intestinos/anatomia & histologia , Perus/anatomia & histologia , Perus/crescimento & desenvolvimento
6.
Clin Dev Immunol ; 2013: 959084, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223608

RESUMO

OBJECTIVE: There is a lack of information about the genotype frequencies of IL-6 -174G/C and -572G/C polymorphisms in Mexicans with rheumatoid arthritis (RA). Therefore, the aim of this study was to evaluate the association of the IL-6 -174G/C and -572G/C polymorphisms in Mexican mestizo with RA. METHODS: We included 137 patients with RA and 102 healthy controls. Patients were assessed for clinical characteristics. IL-6 -174G/C and -572G/C polymorphisms were genotyped using PCR-RFLP analysis. Allele and genotype frequencies and the Hardy-Weinberg equilibrium were computed. Odds ratios (ORs) were computed to identify the risk for RA associated with the presence of GG genotype in comparison with the GC or CC genotypes. RESULTS: The genotype -174GG occurred at a higher frequency in cases and controls (77.4% versus 78.4%, P = 0.845). We found similar results for the genotype -572GG (54% in patients versus 60.8% in controls, P = 0.295). CONCLUSIONS: This is the first study to evaluate the association of -174G/C and -572G/C polymorphisms of the IL-6 gene with RA in Mexican mestizo patients. These two polymorphisms were not associated with RA in the studied sample. Additional studies are required to evaluate if these IL-6 polymorphisms have relevance to the development of more severe disease.


Assuntos
Artrite Reumatoide/genética , Interleucina-6/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adulto , Alelos , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Interleucina-6/sangue , Masculino , México , Pessoa de Meia-Idade
7.
Mycologia ; 104(4): 826-34, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22466796

RESUMO

The purpose of this study was to determine the cultural significance of wild mushrooms in 10 communities on the slopes of La Malinche volcano, Tlaxcala. The frequency and order of mention of each mushroom species in interviews of 200 individuals were used as indicators of the relative cultural significance of each species. A X(2) analysis was used to compare the frequency of mention of each species between males and females, and a Mann-Whitney U test was used to compare the difference in the total number of fungi mentioned by either gender. Traditional names for mushroom species were documented and frequency of mention assessed through multivariate statistics. The fungi with highest frequency of mention were Amanita basii, Lyophyllum decastes, Boletus pinophilus, Gomphus floccosus and Cantharellus cibarius complex. We found significant differences in the frequency of mention of different fungi by males and females but no significant difference was found for the total number of fungi mentioned by either gender. Principal component analysis suggested a cultural regionalization of La Malinche volcano communities based on preferences for consumption and use of traditional names. We observed two groups: one formed by communities on the eastern part of the volcano (with mixed cultures) and the other including communities on the western slope (ethnic Nahua towns). San Isidro Buensuceso is the most distinct community, according to the criteria in this study.


Assuntos
Agaricales , Cultura , Etnobotânica , Antropologia Cultural , Feminino , Preferências Alimentares , Humanos , Entrevistas como Assunto , Conhecimento , Masculino , Medicina Tradicional , México , Análise de Componente Principal
8.
J Immunol Res ; 2017: 7680434, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28758134

RESUMO

Osteoporosis (OP) is highly prevalent in rheumatoid arthritis (RA) and is influenced by genetic factors. Single-nucleotide polymorphism (SNP) rs2073618 in the TNFRSF11B osteoprotegerin (OPG) gene has been related to postmenopausal OP although, to date, no information has been described concerning whether this polymorphism is implied in abnormalities of bone mineral density (BMD) in RA. We evaluated, in a case-control study performed in Mexican-Mestizo women with RA, whether SNP rs2073618 in the TNFRSF11B gene is associated with a decrease in BMD. RA patients were classified as follows: (1) low BMD and (2) normal BMD. All patients were genotyped for the rs2073618 polymorphism by PCR-RFLP. The frequency of low BMD was 74.4%. Higher age was observed in RA with low BMD versus normal BMD (62 and 54 years, resp.; p < 0.001). Worse functioning and lower BMI were observed in RA with low BMD (p = 0.003 and p = 0.002, resp.). We found similar genotype frequencies in RA with low BMD versus RA with normal BMD (GG genotype 71% versus 64.4%, GC 26% versus 33%, and CC 3% versus 2.2%, resp.; p = 0.6). We concluded that in Mexican-Mestizo female patients with RA, the rs2073618 polymorphism of the TNRFS11B gene is not associated with low BMD.


Assuntos
Artrite Reumatoide/genética , Densidade Óssea/genética , Osteoprotegerina/genética , Polimorfismo de Nucleotídeo Único , Fatores Etários , Idoso , Alelos , Artrite Reumatoide/complicações , Artrite Reumatoide/etnologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , México , Pessoa de Meia-Idade , Osteoporose/genética
9.
Clin Exp Rheumatol ; 24(6): 707-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17207391

RESUMO

Pregnancy is a phenomenon that is not totally understood, based on the complex molecular interactions between the mother and the embrio. Once the fecundation is completed the fetus starts to fight for survival. The first challenge is the implantation process and the second one is the interaction with the maternal immune system. This review discusses how the fetus avoids the immune system rejection, and the mechanisms that the maternal immune system adapts in order to be fit for a successful pregnancy. Also, we focus in this paper on the effects of pregnancy in rheumatic diseases, because the myriad clinical outcomes of the disease itself and the obstetric complications dependent of the disease implicated, as for example in rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), spondyloarthropaties and antiphospholipid syndrome (APS).


Assuntos
Complicações na Gravidez , Doenças Reumáticas , Feminino , Humanos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/terapia , Resultado da Gravidez , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/terapia
10.
J Zhejiang Univ Sci B ; 7(6): 429-35, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16691636

RESUMO

Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory disturbances and is used as anti-inflammatory medicine. In nuclear medicine, blood constituents (BC) are labelled with technetium-99m ((99m)Tc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with (99m)Tc. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with (99m)Tc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with (99m)Tc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with (99m)Tc. The data showed significant (P<0.05) alteration of ATI in BC from blood incubated with guava extract.


Assuntos
Células Sanguíneas/metabolismo , Extratos Vegetais/farmacologia , Psidium , Pertecnetato Tc 99m de Sódio/sangue , Animais , Células Sanguíneas/efeitos dos fármacos , Interações Medicamentosas , Marcação por Isótopo/métodos , Masculino , Extratos Vegetais/sangue , Ratos , Ratos Wistar
11.
Braz J Med Biol Res ; 38(1): 111-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15665997

RESUMO

The objective of the present investigation was to determine the contractile effect of crude and acetone leaf extracts of Citrus sinensis (L.) Osb. on mammalian myocardium. Crude leaf extracts have been used in folk medicine to treat neurological disorders. Some flavonoids isolated from this plant presented a positive inotropic effect on myocardium. This motivated us to test the extracts on the atria of guinea pigs of both sexes (300-500 g) and surprisingly we observed inotropic depression instead of an increase in force. The maximum effect of the crude extract was 79.4 +/- 8.1% of the control force amplitude (N = 5 hearts, 10 trials, 27 +/- 0.1 degrees C, stimulus: 2 Hz, 400 V, 0.5 ms). The EC50 for crude, ethanol, acetic, aqueous, and acetone extracts was 300, 300, 600, 1000, and 140 microg/ml, respectively, with a Hill constant of 1.8, 2.0, 2.5, 2.0, and 1.4, respectively. Blockade of cholinergic, beta-adrenergic, or opioid membrane receptors with 1.5 microM atropine sulfate, 1 microM propranolol, and 10 microM naloxone, respectively, did not change the effect of the crude extract. The acetone extract abolished the Bowditch positive staircase phenomenon (N = 5 hearts, 10 trials, 27 +/- 0.1 degrees C), suggesting a possible reduction of the calcium inward current, and also promoted the so-called Woodworth phenomenon. The effect was concentration-dependent and indicated the existence of another inhibitory contractile mechanism such as the simultaneous activation of some of the membrane potassium channels reducing the myocardial action potential duration and further decreasing the cellular calcium entry.


Assuntos
Cardiotônicos/farmacologia , Citrus sinensis/química , Contração Miocárdica/efeitos dos fármacos , Animais , Feminino , Cobaias , Átrios do Coração/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta
12.
Braz J Med Biol Res ; 38(7): 1113-22, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16007283

RESUMO

It has been reported that star fruit can lead to a fatal outcome in uremic patients. The intoxication syndrome consists of hiccups, mental confusion, dizziness, and vomiting. On the other hand, folk medicine uses teas and infusions of carambola leaves to treat headache, vomiting, cough, insomnia, and diabetes. This motivated us to determine if Averrhoa carambola can act on the contractility and automaticity of the guinea pig heart. We measured the atrial isometric force in stimulated left atria and determined the chronotropic changes in spontaneously beating right atria. The carambola leaf extracts (1.5 mg/ml) abolished the contractile force in a concentration-dependent manner. Among the crude, methanolic, ethanolic, aqueous, and acetic extracts, the aqueous one was the most potent (EC50 = 520 +/- 94 microg/ml; flavonoids and tannins are the main constituents; Na+ and K+ contents in 1.0 mg/ml of aqueous extract were 0.12 +/- 0.016 and 1.19 +/- 0.15 mM, respectively). The aqueous extract abolished the positive Bowditch staircase phenomenon and reduced the inotropic response to CaCl2 (0.17-8.22 mM), events that are dependent on the cellular Ca2+ inward current. The adrenergic, muscarinic or opioid membrane receptors do not seem to participate in the mechanism of action of the cardioactive substance(s). In spontaneously beating atria, the aqueous extract promoted a negative chronotropic effect that was antagonized by 0.1 microM isoproterenol bitartrate. With this agonist, the EC50 of the aqueous extract increased from 133 +/- 58 to 650 +/- 100 microg/ml. These data regarding the effect of A. carambola on guinea pig atrial contractility and automaticity indicate an L-type Ca2+ channel blockade.


Assuntos
Coração/efeitos dos fármacos , Magnoliopsida/química , Contração Miocárdica/efeitos dos fármacos , Folhas de Planta/química , Animais , Feminino , Cobaias , Átrios do Coração/efeitos dos fármacos , Magnoliopsida/classificação , Masculino , Extratos Vegetais/farmacologia
13.
Curr Pharm Des ; 9(21): 1679-89, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12871201

RESUMO

The combination of investigation of rare Mendelian forms of hypertension, candidate gene studies, comparative mapping and genome-wide screening in both animal models and man has led to significant progress in determining new mechanisms of blood pressure control. In this review, the newly discovered blood pressure/cardiovascular genes, WNK kinases and angiotensin converting enzyme 2 and the development of a new anti-hypertensive agent PST2238 are discussed. Major genes causing essential hypertension have yet to be discovered, however, there are now over 20 published genome-wide screens for blood pressure controlling genes. Several regions demonstrate suggestive linkage to the trait and there is some overlap of regions between the different studies. It is hoped that new blood pressure genes will ultimately be discovered using this method. Pharmacogenetic studies in hypertension have only been initiated recently, some are described in this paper. Small studies upon single candidate genes, suggest that the contribution of genetics to the inter-individual variation in blood pressure response to anti-hypertensive therapy, is small, approximately 3-5%. Recently micro-arrays with multiple polymorphisms in multiple genes have been used. After accounting for the additive affects of multiple blood pressure loci, an individual's genetic profile appeared to explain up to 50% of the variation in blood pressure response to therapy. Knowledge of the genetic variants that cause hypertension and influence response to anti-hypertensive therapy will ultimately provide a greater understanding of the molecular mechanisms underlying blood pressure control.


Assuntos
Anti-Hipertensivos/farmacologia , Pressão Sanguínea/genética , Hipertensão/genética , Androstanóis/farmacologia , Androstanóis/uso terapêutico , Enzima de Conversão de Angiotensina 2 , Animais , Anti-Hipertensivos/uso terapêutico , Proteínas de Ligação a Calmodulina/farmacologia , Proteínas de Ligação a Calmodulina/uso terapêutico , Carboxipeptidases/genética , Genômica/tendências , Humanos , Hipertensão/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular , Antígenos de Histocompatibilidade Menor , Análise de Sequência com Séries de Oligonucleotídeos , Peptidil Dipeptidase A , Farmacogenética/tendências , Proteínas Serina-Treonina Quinases/genética , Sistema Renina-Angiotensina/genética , Proteína Quinase 1 Deficiente de Lisina WNK
14.
Peptides ; 17(4): 689-93, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8804081

RESUMO

Field recordings of evoked excitatory postsynaptic potentials (pEPSPs) were carried out in the granule cell stratum moleculare following stimulation of the perforant path in rat hippocampal slices. Under control conditions tetanic stimulation produced long-term potentiation (LTP) as measured by an increase in the initial slope of the pEPSPs that lasted for at least 1 h. LTP experiments were repeated with 0.5, 5.0, 50, or 500 nM angiotensin II (AII) present in the bath at the time of tetanization. Induction of LTP was blocked by 50 nM AII; however, normal baseline responses were not affected. At the highest dose tested, 500 nM, a decrease in the amplitude and slope of baseline pEPSPs was observed. When the AII AT1 receptor antagonist losartan was present in the bath AII inhibition of LTP was blocked. The application of losartan alone had no effect on LTP expression. These findings support previous results from in vivo studies demonstrating that activation of AT1 receptors in the dentate gyrus blocks the induction of LTP at the perforant path-granule cell synapse.


Assuntos
Angiotensina II/farmacologia , Potenciais Evocados/efeitos dos fármacos , Hipocampo/fisiologia , Potenciação de Longa Duração/efeitos dos fármacos , Análise de Variância , Animais , Compostos de Bifenilo/farmacologia , Estimulação Elétrica , Hipocampo/efeitos dos fármacos , Imidazóis/farmacologia , Técnicas In Vitro , Losartan , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Sinapses/efeitos dos fármacos , Sinapses/fisiologia , Tetrazóis/farmacologia
15.
Talanta ; 36(12): 1237-41, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18964897

RESUMO

A method is described for the direct spectrofluorimetric determination of ultratraces of cadmium by extraction into 1,2-dichloroethane of the ion-pair formed between the eosinate anion and the cationic complex of Cd(2+) with cryptand 2.2.1. The detection limit for cadmium is 0.5 ng/ml, and the linear working range is from the detection limit to 150 ng/ml. The relative standard deviation is 1.5% at the 100 ng/ml level. The equilibrium constant has been estimated and refined by the Letagrop-DISTR program. The proposed method has been tested in the determination of cadmium in high-purity zinc. The results show good agreement with those found by the more common ICP emission photometry and anodic stripping voltammetry methods.

16.
Braz J Med Biol Res ; 36(5): 661-8, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12715086

RESUMO

Many pharmacological effects have been ascribed to extracts of Psidium guajava L. (guava) leaves. However, in spite of its widespread use in Brazilian folk medicine and a reasonable number of scientific reports about it, we could not find any study dealing with its action on the mammalian myocardium. In the present study, by measuring isometric force, we observed that the crude extract of P. guajava (water-alcohol extract obtained by macerating dry leaves) depresses the guinea pig atrial contractility in a concentration-dependent fashion (N = 8 hearts, 15 trials). The compound with cardiac activity was concentrated by extraction in a Soxhlet apparatus using 17 M glacial acetic acid after removing the less polar fractions (hexane, chloroform, acetone, ethanol and methanol), suggesting that this compound is a highly polar substance. In the isolated guinea pig left atrium the acetic acid fraction (10-800 mg/l) of P. guajava 1) reversibly decreased myocardial force in a concentration-dependent fashion (EC50 = 0.07g/l, N = 5 hearts, 9 trials, P<0.05), 2) increased the atrial relaxation time measured at 20% of the force amplitude up to 35% (91 +/- 15 to 123 +/- 30 ms, N = 3 hearts, 6 trials, P<0.05), 3) abolished the positive staircase effect (Bowditch phenomenon) in a concentration-dependent fashion suggesting a decrease of the cellular inward calcium current (N = 4 hearts, 8 trials, P<0.05), and 4) its inotropic effect was abolished by cholinergic receptor blockade with 1.5 mM atropine sulfate, indicating a cholinergic involvement in the mechanism of action of the extract (N = 7 hearts, 15 trials, P<0.05). The acetic acid extract was 20 times more potent than crude extract (EC50 = 1.4 g/l). The results showed that extracts from P. guajava leaves depress myocardial inotropism.


Assuntos
Cardiotônicos/farmacologia , Contração Miocárdica/efeitos dos fármacos , Psidium , Animais , Feminino , Cobaias , Átrios do Coração/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta , Plantas Medicinais
17.
Rev Inst Med Trop Sao Paulo ; 41(6): 351-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10671288

RESUMO

The precise microenvironment of Paracoccidioides brasiliensis has not yet been discovered perhaps because the methods used are not sensitive enough. We applied to this purpose the polymerase chain reaction (PCR) using three sets of specific primers corresponding to two P. brasiliensis genes. This fungus as well as several other fungi, were grown and their DNA obtained by mechanical disruption and a phenol chloroform isoamylalcohol-based purification method. The DNA served for a PCR reaction that employed specific primers from two P. brasiliensis genes that codify for antigenic proteins, namely, the 27 kDa and the 43 kDa. The lowest detection range for the 27 kDa gene was 3 pg. The amplification for both genes was positive only with DNA from P. brasiliensis; additionally, the mRNA for the 27 kDa gene was present only in P. brasiliensis, as indicated by the Northern analysis. The standardization of PCR technology permitted the amplification of P. brasiliensis DNA in artificially contaminated soils and in tissues of armadillos naturally infected with the fungus. These results indicate that PCR technology could play an important role in the search for P. brasiliensis' habitat and could also be used in other ecological studies.


Assuntos
Primers do DNA/genética , DNA Fúngico/genética , Ecossistema , Paracoccidioides/genética , Reação em Cadeia da Polimerase/métodos , Animais , Tatus/microbiologia , Sequência de Bases , Northern Blotting , DNA Fúngico/isolamento & purificação , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Paracoccidioides/isolamento & purificação , Reação em Cadeia da Polimerase/normas , RNA Mensageiro/isolamento & purificação
18.
Pol J Vet Sci ; 5(2): 103-15, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12189946

RESUMO

The majority of interactions between microorganisms and animals are based on convenient relations for both of them. Symbiotic microorganisms, like intestinal microbiota, produce important vitamins for animals and protects them from putative pathogens. In general, for monogastric animals, the main contribution of intestinal microorganisms is to supply with growth factors the animal diet, and in some cases they are responsible for providing essential vitamins (e.g. vitamin K). Some particular and relatively few microbes like viruses, bacteria, fungi, protozoa and algae are responsible for animal illness. Because microorganisms are easily dispersed, display physiological diversity, and tolerate extreme conditions, they are ubiquitous and may contaminate and grow in many products, including food and raw materials. Foodborne diseases are caused by consumption of contaminated food or beverages. Many different disease-causing pathogens can contaminate food, so there are many different foodborne infections. In addition, poisonous chemicals and biological toxins can cause disease if they are present in food. To know how a particular disease is spreading is an important matter to take appropriate steps to stop it. For example Escherichia coli O157:H7 infections can spread through contaminated food (meat, vegetables, cheese, etc.), contaminated drinking water or juices, contaminated swimming water and from person to person. Among foodborne pathogens, the most frequently detected are bacteria, but also parasitic protozoa and worms, viruses, natural toxins and other pathogenic agents like prions are important agents for foodborne diseases. Particular pathogenic types of E. coli, classified by their specific pathogenic mechanisms (toxins, adhesins, invasiveness, etc.) are actually known as E. coli virotypes. Enterohaemorrhagic E. coli (EHEC), which constitute the main part of this review, were also named verotoxigenic E. coli (VTEC) or Shiga toxigenic E. coli (STEC). EHEC strains cause haemorrhagic colitis (HC), haemolytic uremic syndrome (HUS) and thrombotic thrombocytopaenic purpura (TP) in humans. They synthetize shigatoxins (verotoxins) which are potent cytotoxic substances, adherence factors and enterohaemolysin. EHEC are responsible for many outbreaks of bloody diarrhoea caused by contaminated foods: beef, milk, fruits, juice, water, etc. The most important serogroups among EHEC are O26, O111 and O157, being O157:H7 the most relevant serotype in foodborne outbreaks. The normal intestinal microflora of cattle was found to be the most relevant reservoir of EHEC strains.


Assuntos
Doenças dos Bovinos/microbiologia , Bovinos/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/classificação , Microbiologia de Alimentos , Animais , Surtos de Doenças , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/classificação , Europa (Continente)/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Estados Unidos/epidemiologia
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