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1.
Acta cir. bras ; 34(2): e201900207, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-989054

Résumé

Abstract Purpose: To evaluate red propolis, gum arabic and L-lysine activity on colorectal preneoplastic lesions induced by azoxymethane (AOM). Methods: The study featured 4 control groups (I-IV) and 4 experimental groups (V-VIII), totaling 48 rats. Once a week for 2 weeks, animals on control groups received saline, while animals in experimental groups received azoxymethane (15 mg/kg i.p.). The follow up along 16 weeks included daily oral gavage to administer water (I and V), L-lysine (150 mg/kg)(II and VI), própolis (100mg/5ml/kg)(III and VII), or gum arabic (5ml/kg)(IV and VIII). Was performed surgery on the animals in the end of this time in order to collect blood for biological assays (TBARS, GSH), followed by their sacrifice to tissue extract. Results: Oxidative stress (TBARS) and the number of aberrant crypt foci (ACF) in distal colon were lower using própolis (p<0.01 for both parameters). Gum arabic reduced preneoplastic lesions (ACF ≤ 4 crypts) on distal colon and on the entire colon (p<0.05). Conclusions: Red propolis reduced AOM-induced oxidative stress (TBARS) and total number of ACF in the distal colon. L-lysine neither protected against nor enhanced AOM-induced ACF. Gum arabic reduced the number of ACF.


Sujets)
Animaux , Mâle , Rats , États précancéreux/prévention et contrôle , Propolis/pharmacologie , Tumeurs colorectales/prévention et contrôle , Stress oxydatif/effets des médicaments et des substances chimiques , Gomme arabique/pharmacologie , Lysine/pharmacologie , États précancéreux/induit chimiquement , Oxyde de diméthyl-diazène , Cancérogènes , Tumeurs colorectales/induit chimiquement , Rat Wistar , Modèles animaux de maladie humaine
2.
Acta cir. bras ; 31(12): 793-800, Dec. 2016. tab, graf
Article Dans Anglais | LILACS | ID: biblio-837657

Résumé

ABSTRACT PURPOSE: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis). METHODS: Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively. Groups D, E and F (non-operated controls) received L-lysine, celecoxib and H2O, respectively. The L-lysine dose was 150 mg/kg and that of celecoxib was 20 mg/kg. The colon was analyzed for the presence of aberrant crypt foci (ACF) under a stereomicroscope.The tissue was stained with hematoxylin and eosin and PAS alcian blue. RESULTS: There were rare ACF, and there was no statistically significant difference between the groups. Histopathologic study of the ureteral epithelium identified moderate to severe urothelial hyperplasia in rats with ureterosigmoidostomy. Transitional hyperplasia in the ureters of animals receiving L-lysine (A) showed an apparent difference compared to the control (C) (P=0.2424). There was no dysplasia or atypia CONCLUSION: L-lysine does not promote carcinogenesis of the intestinal and urethelial epithelium of rats subjected to ureterosigmoidostomy at the doses and times studied.


Sujets)
Animaux , Femelle , Rats , Côlon sigmoïde/chirurgie , Stomies chirurgicales , Foyers de cryptes aberrantes/anatomopathologie , Carcinogenèse , Tumeurs de l'intestin/étiologie , Lysine/pharmacologie , Tumeurs de la vessie urinaire/étiologie , Urétérostomie/méthodes , Rat Wistar , Modèles animaux de maladie humaine , Stomies chirurgicales/effets indésirables , Muqueuse intestinale/anatomopathologie
3.
Rev. Col. Bras. Cir ; 43(2): 80-86, Mar.-Apr. 2016. tab, graf
Article Dans Anglais | LILACS | ID: lil-782916

Résumé

ABSTRACT Objective: to evaluate the effect of L-lysine in the bladder and intestinal epithelia in rats submitted to vesicosigmoidostomy. Methods: we divided forty Wistar rats into four groups: group I - control group (Sham); group II - submitted to vesicosigmoidostomy and treated with L-lysine 150mg/kg; group III - submitted only to vesicosigmoidostomy; and group IV - received L-lysine 150mg/kg. After eight weeks the animals were sacrificed. Results: in the bladders of all operated animals we observed simple, papillary and nodular hyperplasia of transitional cells, transitional cell papillomas and squamous metaplasia. As for the occurrence of aberrant crypt foci in the colons of operated animals, we did not observe statistically significant differences in any of the distal, proximal and medium fragments, or in all fragments together (p=1.0000). Conclusion: Although statistically there was no promotion of carcinogenesis in the epithelia of rats treated with L-lysine in the observed time, it was clear the histogenesis of bladder carcinogenesis in its initial phase in all operated rats, this being probably associated with chronic infection and tiny bladder stones.


RESUMO Objetivo: o objetivo deste trabalho é avaliar o efeito da L-lisina nos epitélios vesical e intestinal de ratas submetidas à vesicossigmoidostomia. Métodos: quarenta ratas Wistar, foram divididas em quatro grupos: grupo I- grupo controle (Sham); grupo II- submetido à vesicossigmoidostomia e tratado com L-lisina 150mg/kg; grupo III- submetido apenas à vesicossigmoidostomia; e grupo IV- recebeu L-lisina 150mg/kg. Após oito semanas os animais foram sacrificados. Resultados: na bexiga de todos os animais operados observou-se hiperplasia simples, papilar e nodular de células transicionais, papiloma de células transicionais e metaplasia escamosa. Quanto à ocorrência de focos de criptas aberrantes nos colos dos animais operados, não foi evidenciado diferença estatística significante em nenhum dos fragmentos distal, proximal e médio, e todos juntos (P=1,0000). Conclusão: apesar de, estatisticamente, não ter havido promoção de carcinogênese nos epitélios dos ratos tratados com L-lisina, no tempo observado, é nítida a histogênese da carcinogênese de bexiga em sua fase inicial, no epitélio vesical, em todos os ratos operados, estando esta provavelmente associada à infecção crônica e aos diminutos cálculos vesicais.


Sujets)
Animaux , Rats , Complications postopératoires/induit chimiquement , Côlon sigmoïde/chirurgie , Vessie urinaire/effets des médicaments et des substances chimiques , Vessie urinaire/anatomopathologie , Urétérostomie , Carcinogenèse/induit chimiquement , Muqueuse intestinale/effets des médicaments et des substances chimiques , Muqueuse intestinale/anatomopathologie , Lysine/pharmacologie , Rat Wistar
4.
Acta cir. bras ; 29(7): 423-428, 07/2014. tab, graf
Article Dans Anglais | LILACS | ID: lil-714578

Résumé

PURPOSE: To evaluate the genotoxicity of propolis and L-lysine, as well as their effects on the possible cellular damage in erythroblasts (bone marrow) and leukocytes (peripheral blood) caused by the carcinogen BBN (n - butyl - n {4 - hydroxybutyl} nitrosamine) in rats subjected to bladder carcinogenesis and treated with green propolis and L-lysine. METHODS: One hundred and twenty five rats were distributed into the following groups: I, IIA, IIB, III, K, L M N, X, XI, XII and XIII. Groups I to X received BBN in drinking water for 14 weeks (wks). Group I was treated with intragastric (ig) propolis at 150 mg/kg body weight, for 44 wks, beginning 30 days before start of BBN. Groups IIA and III were treated with propolis (150 mg/kg), for 40 wks, subcutaneous (sc) and ig, respectively, beginning simultaneously with BBN. On the 32nd wk, the animals of groups L, M and N were treated ig with L-lysine (300 mg/kg), celecoxib (30 mg/kg) and propolis (300 mg/kg), respectively, up to the 40th wk. The groups that received only BBN (IIB and K) were treated with water, sc and orally, respectively, for 40 wks. Groups XI, XII and XIII received respectively propolis (150 mg/kg), L-lysine (150 mg/kg) and water ig for 40 wks. After 40 wks, the surviving animals were anesthetized and subjected to femoral bone marrow aspiration and blood collection from the aorta, for CA and MNT, respectively, for investigation of genotoxicity. RESULTS: Groups IIB and K, which received only BBN and water, showed the greatest DNA damage in peripheral leukocytes (CA) and largest number of micronuclei in bone marrow erythrocytes (MNT) in relation to all other groups that received BBN and lysine and/or propolis (p<0.001). CONCLUSIONS: Both propolis and L-lysine are effective in protecting against genotoxicity, as well not being genotoxic themselves toward the cells evaluated, at the doses and times administered and according to the two tests utilized. .


Sujets)
Animaux , Cellules de la moelle osseuse/effets des médicaments et des substances chimiques , Carcinogenèse/effets des médicaments et des substances chimiques , Lymphocytes/effets des médicaments et des substances chimiques , Lysine/pharmacologie , Propolis/pharmacologie , Pyrazoles/pharmacologie , Sulfonamides/pharmacologie , Anticarcinogènes/pharmacologie , Tests de cancérogénicité , Test des comètes , Altération de l'ADN , Tests de micronucleus , Rat Wistar , Valeurs de référence , Reproductibilité des résultats , Facteurs temps , Tumeurs de la vessie urinaire/anatomopathologie , Tumeurs de la vessie urinaire/prévention et contrôle
5.
Acta cir. bras ; 27(2): 185-192, Feb. 2012. ilus, tab
Article Dans Anglais | LILACS | ID: lil-614540

Résumé

PURPOSE: To determine the effects of green propolis extracted in L-lysine (WSDP) and of L- lysine for 40 weeks on induced rat bladder carcinogenesis. METHODS: The animals (groups I, II, III, IV, V and VI) received BBN during 14 weeks. Group I was treated with propolis 30 days prior received BBN, and then these animals were treated daily with propolis; Groups II and III was treated with subcutaneous and oral propolis (respectively) concurrently with BBN. The animals of Group IV were treated L-lysine; Group V received water subcutaneous; and Group VI received only to BBN. Among the animals not submitted to carcinogenesis induction, Group VII received propolis, Group VIII received L-lysine and Group IX received water. RESULTS: The carcinoma incidence in Group I was lower than that of control (Group VI). The carcinoma multiplicity in Group IV was greater than in Group VI. All animals treated with L-lysine developed carcinomas, and they were also more invasive in Group IV than in controls. On the other hand, Group VIII showed no bladder lesions. CONCLUSION: The WSDP is chemopreventive against rat bladder carcinogenesis, if administered 30 days prior to BBN , and that L-lysine causes promotion of bladder carcinogenesis.


OBJETIVO: Determinar os efeitos da própolis verde extraída em L - Lisina (WSDP) e da L-Lisina por 40 semanas em ratos induzidos a carcinogênese de bexiga. MÉTODOS: Os animais (grupos I, II, III, IV, V e VI) receberam BBN por 14 semanas. O grupo I foi tratado com própolis 30 dias antes de receber BBN e em seguida estes animais foram tratados diariamente com própolis; Os grupos II e III foram tratados com própolis subcutânea e oral (respectivamente) e concorretemente com BBN. Os animais do grupo IV foram tratados com L- Lisina; o grupo V recebeu água subcutânea; o grupo VI recebeu apenas BBN. Entre os animais não submetidos a indução de carcinogênese, Grupo VII, receberam própolis, Grupo VIII, receberam L-Lisina e Grupo IX receberam água. RESULTADOS: A incidência de carcinoma no grupo I foi menor que no grupo controle (grupo IV) A multiplicidade de carcinoma no grupo IV foi maior que no grupo VI. Todos os animais tratados com L - Lisina desenvolveram carcinomas e estes foram mais invasivos no grupo IV que no grupo controle. Por outro lado o grupo VIII não apresentou lesões. CONCLUSÃO: WSDP é quimiopreventiva contra a carcinogese de bexiga se administrada 30 dias antes do início do BBN, e a L - Lisina causa promoção da carcinogênese de bexiga.


Sujets)
Animaux , Femelle , Rats , 4-[Butyl(nitroso)amino]butan-1-ol/usage thérapeutique , Lysine/pharmacologie , Extraits de plantes/usage thérapeutique , Propolis/usage thérapeutique , Tumeurs de la vessie urinaire/prévention et contrôle , Anticarcinogènes/pharmacologie , Anticarcinogènes/usage thérapeutique , Cancérogènes , Extraits de plantes/pharmacologie , Propolis/pharmacologie , Rat Wistar , Facteurs temps , Résultat thérapeutique , Tumeurs de la vessie urinaire/induit chimiquement , Tumeurs de la vessie urinaire/traitement médicamenteux , Tumeurs de la vessie urinaire/anatomopathologie
6.
Braz. j. oral sci ; 9(1): 25-29, Jan.-Mar. 2010. ilus, tab
Article Dans Anglais | LILACS, BBO | ID: lil-578042

Résumé

Aim: This study evaluated the influence of different chemomechanical caries removal techniqueson the bond strength of an adhesive system to caries-affected and healthy dentin. Methods:Thirty healthy teeth were randomly divided into three groups: Group 1 (control): no cariesremoval technique was applied; Group 2: chemomechanical technique using Carisolv®; andGroup 3: chemomechanical technique using Papacárie®Twenty caries-affected teeth were divided .into two groups: Group 4: chemomechanical technique using Carisolv; and Group 5:chemomechanical technique using Papacárie. The teeth received the application of an etch-andrinse adhesive system, were restored with composite resin, and then sectioned to obtain 4 hourglassshaped slabs from each specimen, which were subjected to a microtensile bond strength test. Datawere analyzed statistically by ANOVA and Tukey’s test (a=0.05). Results: G1 (13.387 ± 6.1074),G2 (18.123 ± 3.2611) and G3 (12.781 ± 4.5652) presented statistically significant higher meanbond strength values than the other groups (p<0.05), but did not differ significantly from each other(p>0.05). G4 (6.228 ± 5.3435) and G5 (6.482 ± 3.2076) presented the lowest mean bondstrength values and were statistically similar to each other (p>0.05). Conclusions: Neither of thechemomechanical caries removal methods interfered in the resin-dentin bond strength. However,lower tensile bond strength was found to caries-affected dentin.


Sujets)
Humains , Caries dentaires/thérapie , Agents de collage dentinaire/composition chimique , Dentine/effets des médicaments et des substances chimiques , Acide glutamique/pharmacologie , Techniques in vitro , Leucine/pharmacologie , Lysine/pharmacologie , Papaïne/pharmacologie , Mordançage à l'acide , Analyse de variance , Résines acryliques/composition chimique , Propriétés de surface , Résistance à la traction , Facteurs temps
7.
Prensa méd. argent ; 95(2): 96-106, abr. 2008.
Article Dans Espagnol | LILACS | ID: lil-497661

Résumé

La hiperlipidemia por lipoproteína a -LDL más apo a- es un factor de riesgo vascular aterotrombótico, familiar, independiente y poderoso, llamativamente desconsiderado. Este trabajo tiene como objetivo su mejor diagnóstico y tratamiento.


Sujets)
Humains , Apolipoprotéines A/génétique , Cholestérol HDL/métabolisme , Cholestérol LDL/génétique , Cholestérol LDL/métabolisme , Maladies cardiovasculaires/anatomopathologie , Lipoprotéine (a) , Lysine/pharmacologie , Acide nicotinique/usage thérapeutique , Proline/pharmacologie
8.
Braz. dent. j ; 17(2): 110-116, 2006. ilus
Article Dans Anglais | LILACS | ID: lil-433496

Résumé

A utilização do CarisolvTM tem sido proposta como um método auxiliar à raspagem e ao alisamento radicular (RAR), a fim de facilitar a descontaminação da superfície da raiz. O objetivo deste estudo foi avaliar, através da microscopia eletrônica de varredura (MEV), as características das superfícies radiculares, após a aplicação do CarisolvTM em associação à RAR. Sessenta dentes humanos extraídos devido à doença periodontal foram divididos em 6 grupos: 1) RAR ; 2) CarisolvTM (aplicação passiva) + RAR; 3) CarisolvTM (aplicação ativa) + RAR; 4) CarisolvTM (aplicações múltiplas) + RAR; 5) RAR + EDTA a 24%; 6) CarisolvTM + RAR + EDTA a 24%. CarisolvTM foi aplicado às superfícies radiculares por 30 s, seguido de raspagem e alisamento radicular, que consistiu de 50 movimentos com curetas de Gracey no sentido corono-apical, co o instrumento paralelo ao longo eixo do dente. A única exceção foi o grupo 4, no qual as raízes foram instrumentadas até obter uma superfície lisa, dura e com aspecto vítreo. Os espécimens tratados foram preparados e examinados em MEV. Os resultados demonstraram que a associação do CarisolvTM aos procedimentos periodontais mecânicos proporcionou modificações significativas na superfície radicular quando comparada à raspagem e ao alisamento radicular, apenas quando o CarisolvTM foi aplicado de forma ativa. A aplicação do CarisolvTM uma única vez, apresentou um efeito limitado na capacidade de remoção de smear layer, sendo que aplicações sucessivas apresentaram resultados comparáveis àqueles obtidos após a aplicação do EDTA.


Sujets)
Humains , Acide glutamique/pharmacologie , Leucine/pharmacologie , Lysine/pharmacologie , Racine dentaire/effets des médicaments et des substances chimiques , Analyse de variance , Détartrage dentaire , Microscopie électronique à balayage , Surfaçage radiculaire , Boue dentinaire , Propriétés de surface/effets des médicaments et des substances chimiques , Racine dentaire/ultrastructure
9.
Medical Journal of Cairo University [The]. 2004; 72 (Supp. 2): 15-8
Dans Anglais | IMEMR | ID: emr-67647

Résumé

A purposeful sample of 40 children with cerebral palsy with age range from 2 to 8 years, attending El-Sahel Teaching Hospital, was evaluated by EEG and IQ. Twenty children received lysine orally in a dose of 12 mg/day/kg for 10-12 months. Post treatment EEG revealed improvement of EEG abnormalities together with evaluation of IQ in 14 cases [70%]. Lysine may play a role in controlling electrical activity and improving IQ in cerebral palsy. More researches are needed regarding the early administration of lysine in cerebral palsy


Sujets)
Humains , Mâle , Femelle , Lysine/pharmacologie , Enfant , Intelligence , Électroencéphalographie
10.
Indian J Physiol Pharmacol ; 2001 Jul; 45(3): 367-72
Article Dans Anglais | IMSEAR | ID: sea-108791

Résumé

Monoclonal antibodies (MAb) constitute the centre of all in-vitro diagnostic measures and almost all in-vivo therapeutic manoeuvres now. Production emphasis for these antibodies is having a current shift from animal-based large-scale culture to in-vitro bioreactor-based high-density culture. One of the major difficulties in high-density culture is end-metabolite accumulation in batch and fed-batch cultures in the forms of H+, NH4+ etc.. thereby reducing cellular growth and secretions. In the present study, effects of added proton carries--NAD and NADP--over and above the metabolic pools of the molecules, were examined on the cellular growth and secretion kinetics. Although NADP fortification showed a remarkable improvement in cellular growth (time dependent 200-300% improvements compared to controls) and size, cumulative MAb titre was better with NAD fortification. Combined additional loads of the proton carriers would be interesting to study in high density culture conditions.


Sujets)
Algorithmes , Animaux , Division cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire , Chromatographie en phase liquide à haute performance , Milieux de culture , Électrophorèse sur gel de polyacrylamide , Test ELISA , Hybridomes/effets des médicaments et des substances chimiques , Lysine/pharmacologie , Souris , Muromonab-CD3/biosynthèse , NAD/pharmacologie , Protons , Spectrophotométrie UV , Activation chimique
11.
Medicina (B.Aires) ; 60(5/1): 580-6, 2000. graf
Article Dans Espagnol | LILACS | ID: lil-275468

Résumé

El clonixinato de lisina (CL) es un antiinflamatorio no esteroide (AINE) con pocos efectos adversos, por lo que se ha postulado que a concentraciones equivalentes a las encontradas en plasma humano después de dosis terapéuticas inhibiría en escaso grado la cicloxigenasa I (COX-I). Se efectuaron 3 experimentos. Experimento 1: se estudió el efecto in vitro de CL en concentraciones de 4 y 6 ug/ml, las que se corresponden con las alcanzadas en plasma con una dosis oral de 125 mg. Los segmentos de vesícula biliar (n = 6) se incubaron con 0.25 uCi de ácido araquidónico 14C y se midió la producción de prostaglandina E 2, prostaglandina F 2a y prostaglandina 6 ceto F 1a. El CL no modificó la producción basal de ninguna de las tres prostaglandinas, pero con 6 ug/ml disminuyó significativamente la producción de ácido 5- hidroxieicosatetraenico (5-HETE). Experimento 2: se administró una infusión continua de CL a 6 pacientes en el pre operatorio inmediato para lograr una concentración en estado estacioanrio entre 4 y 6 ug/ml. Se incubaron segmentos de vesícula biliar de estos 6 pacientes y de 6 pacientes control no tratados con ácido araquidónico 14 C. Se observó que los segmentos de vesícula biliar tratados con CL no mostraron inhibición de la producción de ninguna de las tres PGs, mientras que el 5-HETE liberado al medio fue significativamente menor. Experimento 3: 18 pacientes recibieron bolos EV de: CL 100mg (n1, = 6); CL 200 mg (n2, = 6) o indometacina (INDO) 50 mg (n3 = 6). Con ninguna de las dos dosis de CL se obtuvo inhibición de la síntesis de PGs, por el contrario de INDO inhibió su síntesis. Cuando se valoró la producción de 5-HETE, los dos AINES estudiados de se comportaron en forma distinta. El tratamiento con INDO no modificó el 5-F-HETE producido, mientras que el tratamiento con CL lo inhibió significativamente. En los tres tipos de estudios realizados in vitro e in vivo: infusión continua y bolo IV, el CL no inhibió la síntesis de PGs y disminuyó significativamente el 5-HETE.


Sujets)
Humains , Anti-inflammatoires non stéroïdiens/pharmacologie , Vésicule biliaire/effets des médicaments et des substances chimiques , Acide hydroxyeïcosatétraénoïque/biosynthèse , Lysine/analogues et dérivés , Lysine/pharmacologie , Prostaglandines/biosynthèse , Anti-inflammatoires non stéroïdiens/métabolisme , Technique de Western , Vésicule biliaire/enzymologie , Indométacine/pharmacologie , Lysine/métabolisme
12.
Braz. j. med. biol. res ; 31(6): 811-8, jun. 1998. graf
Article Dans Anglais | LILACS | ID: lil-210971

Résumé

We have investigated the effects of L-arginine, D-arginine and L-lysine on airway smooth muscle responsiveness to spasmogens in vitro. Both L-arginine and D-arginine (100 mM) significantly reduced the contractile potency and maximal contractile response to histamine but not to methacholine or potassium chloride in guinea-pig epithelium-denuded isolated trachea. Similarly, the contractile response to histamine was significantly reduced by L-arginine (100 mM) in rabbit epithelium-denuded isolated bronchus. The amino acid L-lysine (100 mM) failed to significantly alter the contractile potency of histamine in guinea-pig isolated trachea (P> 0.05). In guinea-pig isolated trachea precontracted with histamine, both L-arginine and D-arginine produced a concentration-dependent relaxation which was not significantly altered by epithelium removal or by the presence of the nitric oxide synthase inhibitor, N G -nitro L-arginine methyl ester (L-NAME; 50 µM). Thus, at very high concentrations, arginine exhibit a non-competitive antagonism of histamine-induced contraction of isolated airway preparations that was independent of the generation of nitric oxide and was not dependent on charge. These observations confirm previous studies of cutaneous permeability responses and of contractile responses of guinea-pig isolated ileal smooth muscle. Taken together, the data suggest that high concentrations of arginine can exert an anti-histamine effect


Sujets)
Animaux , Cochons d'Inde , Lapins , Arginine/pharmacologie , Bronches/effets des médicaments et des substances chimiques , Antihistaminiques des récepteurs H1/pharmacologie , Techniques in vitro , Muscles lisses/effets des médicaments et des substances chimiques , Trachée/effets des médicaments et des substances chimiques , Bronchoconstricteurs/pharmacologie , Antienzymes/pharmacologie , Épithélium/effets des médicaments et des substances chimiques , Histamine/pharmacologie , Lysine/pharmacologie , Chlorure de méthacholine/pharmacologie , Contraction musculaire , L-NAME/pharmacologie
13.
Medicina (B.Aires) ; 58(3): 291-4, 1998. graf
Article Dans Espagnol | LILACS | ID: lil-213405

Résumé

Las ulceraciones de la mucosa gástrica y colónica producida por los antiinflamatorios no esteroides (AINES) son producidas por la reducción de la síntesis de prostaglandinas (PGs) por inhibición de la ciclooxigenasa. Por otro lado se ha demosntrado que los productos de la 5-lipoxigenasa (5-LO) son agentes ulcerogénicos. En algunos casos el uso de AINES se acompaña de una mayor producción de productos de la 5-LO debido a un exceso de sustrato (ácido araquidónico) al estar bloqueada la ciclooxigenasa. Cuando ocurre esto último aumentan los efectos lesivos de los AINES ya que no sólo disminuyen las PGS citoprotectoras, sino que también aumentan los productos de la 5-LO. El objeto de este trabajo, fue estudiar en segmentos de colon aislado de pacientes con neoplasias el efecto del Clonixinato de lisina (CL) y de la indometacina (INDO) sobre la síntesis de PGs e hidroxiácidos (HETEs). Las concentraciones de CL (4 y 6 mug/ml) y de indo (0,035 y 0,035 y 0,35 mug/ml utilizadas, se corresponden con los valores plasmáticos alcanzados con dosis terapéuticos orales de ambas drogas. Se observó que el CL con ninguna de las dosis utilizadas modificó la producción basal de PGE(2). Por el contrario la INDO inhibió significativamente la síntese de PGE(2) con ambas dosis. Llamó la atención que el CL tanto a 4 mug/ml como 6 mug/ml produjo una profunda disminución en la producción de 5-HETE, efecto sólo observado con la concentración más alta de INDO. Este resultado indicaría una probable acción inhibitoria sobre la 5-LO, primeira enzima del camino metabólico del ácido araquidónico hacia formación de HETEs y Lts. Concluimos que el CL en dosis terapéuticas tiene un mecanismo de acción diferente al de los AINES clásicos. Los datos obtenidos en este estudo explicarían la baja incidencia de efectos gastrointestinales lesivos observados con CL.


Sujets)
Humains , Anti-inflammatoires non stéroïdiens/pharmacologie , Arachidonate 5-lipoxygenase/antagonistes et inhibiteurs , Tumeurs du côlon/traitement médicamenteux , Côlon/effets des médicaments et des substances chimiques , Inhibiteurs des cyclooxygénases , Muqueuse gastrique/effets des médicaments et des substances chimiques , Indométacine/pharmacologie , Lysine/analyse , Lysine/pharmacologie , Anti-inflammatoires non stéroïdiens/usage thérapeutique , Arachidonate 5-lipoxygenase/biosynthèse , Lysine/usage thérapeutique , Prostaglandin-endoperoxide synthases/biosynthèse
14.
Indian J Biochem Biophys ; 1997 Dec; 34(6): 518-23
Article Dans Anglais | IMSEAR | ID: sea-28231

Résumé

The amino acids lysine, glycine, alanine, glutamate and aspartate formed adducts with galactose at physiological pH and temperature as shown by incorporation of U[14C] galactose. The percentage of galactose reacting with lysine, glycine, alanine, glutamate and aspartate was 4.5 to 7.8, 7.9 to 10.8, 3.2 to 4.6, 2.8 to 4.8 and 3 to 5.2, respectively. Studies with lysine showed that the extent of glycation of the free amino acid increased with time. Incubation of lens homogenate with galactose, effected glycation of proteins. Addition of lysine in concentrations of 5 and 10 mM to equimolar concentrations of galactose decreased the glycation of lens proteins by 64% to 71%; glycine, alanine, glutamate and aspartate decreased glycation by 23 to 68%, 32 to 61%, 35 to 56% and 26 to 61% respectively. Under similar conditions, glycine reacts to a greater extent than lysine, alanine, glutamic and aspartic acids. However, lysine was more effective than glycine, alanine, aspartic and glutamic acids in decreasing glycation of lens proteins by galactose. The decrease of glycation with added lysine increased with time. In general increase of amino acid concentration rather than that of sugar augmented the decrease of glycation of lens proteins.


Sujets)
Adulte , Acides aminés/pharmacologie , Cataracte/étiologie , Cristallines/composition chimique , Galactose/métabolisme , Glucose/métabolisme , Glycosylation , Humains , Lysine/pharmacologie , Adulte d'âge moyen
15.
Alexandria Journal of Veterinary Sciences [AJVS]. 1996; 12 (2): 117-130
Dans Anglais | IMEMR | ID: emr-40332

Résumé

An experiment was conducted to evaluate the growth performance and body composition of Tilapia nilotica fingerlings fed diets supplemented with methionine and /or lysine at different levels. A total of 216 Tilapia nilotica of nearly similar weight [22 g] were allotted into 9 groups. Fish meal, soybean oil meal, ground yellow corn, wheat bran, cottonseed oil, carboxymethyl cellulose, mineral mixture and vitamin mixture were used to formulate a balanced basal diet. Methionine and lysine were supplemented in percentages of 0.0 + 0.0, 0.27 + 0.0, 0.54 + 0.0, 0.0 + 0.81, 0.0 + 1.62, 0.27 + 0.81, 0.27 + 1.62, 0.54 + 0.81, 0.54 + 1.62 to the diets 1 to 9, respectively. Fish of groups 2 to 9 which were fed on diets supplemented with methionine and /or lysine at different levels achieved the best values of the tested performance parameters [total and weekly body weight gain, SGR, FCR, PER, increase in length and condition factor] when compared to group 1 [control group] which was fed on the basal diet without any supplementation. The average dressing% and organoleptic characteristic score did not differ significantly between fish groups. The proximate fish body composition was not greatly affected by any dietary treatment. Retention of dry matter, crude protein and ash in fish of groups 2 to 9 showed the highest values when compared to those of group 1 [control group]. It can be concluded that supplementation of methionine and /or lysine to ordinary diets significantly improves the growth performance and nutrient retention of Tilapia nilotica


Sujets)
Méthionine , Lysine/pharmacologie , Tilapia/croissance et développement
16.
Indian J Biochem Biophys ; 1993 Aug; 30(4): 199-203
Article Dans Anglais | IMSEAR | ID: sea-29026

Résumé

The lysine- and threonine-sensitive isoenzymes of aspartate kinase were purified to homogeneity from spinach leaves and polyclonal antibodies were raised in rabbits. The antibodies were characterized by various immunological tests like Ouchterlonys-double-diffusion, titrations of the inhibition of enzyme activity and ELISA. The antibodies against the lysine-sensitive isoenzyme could recognise as little as 50 ng of the pure antigen protein and that against the threonine-sensitive form could recognise 200 ng of the protein in the ELISA tests. The immunological tests have also shown that the lysine and threonine sensitive isoenzymes of aspartate kinase share some common antigenic determinants and differ in others.


Sujets)
Animaux , Aspartate kinase/isolement et purification , Test ELISA , Épitopes/analyse , Isoenzymes/isolement et purification , Cinétique , Lysine/pharmacologie , Plantes/enzymologie , Lapins/immunologie , Thréonine/pharmacologie
18.
Arch. latinoam. nutr ; 36(3): 483-94, sept. 1986. tab
Article Dans Portugais | LILACS | ID: lil-44811

Résumé

O presente trabalho teve por objetivo obter um concentrado proteico de folhas de mandioca através de modificaçöes na metodologia já existente. O valor nutricional da folha de mandioca e do concentrado proteico foi avaliado através de análises químicas, ensaio biológico e suplementaçäo da proteína tanto do concentrado como da folha com os aminoácidos limitantes lisina e metionina.. Dos resultados obtidos foram sugeridas as seguintes conclusöes: - A folha de mandioca e o concentrado proteico da folha apresentaram um teor proteico elevado, 25.2% e 34%, respectivamente. - Ensaios biológicos tanto do concentrado como da folha com o aminoácido lisina mais metionina mostrou ser eficiente, dando maiores valores para PER, NPU e digestibilidade. - A adiçäo do aminoácido lisina näo mostrou ter nunhum efeito significativo na melhora do valor nutricional da proteína. - Exames anátomo patológico dos órgäos dos animais näo revelaram nenhuma alteraçäo, indicando näo haver fatores tóxicos na folha e no concentrado


Sujets)
Rats , Animaux , Aliment enrichi , Lysine/pharmacologie , Manihot , Méthionine/pharmacologie , Protéines de légume/isolement et purification , Poids , Valeur nutritive
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