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1.
Rev. chil. nutr ; 41(4): 433-438, dic. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-734788

RESUMO

Nutritional deficit of omega-3 long-chain polyunsaturated fatty acids (omega-3 LCPUFA), mainly eicosapentaenoic acid and docosahexaenoic acid, in the western population due the low consumption of marine products is actually a matter of concern. The classical alternative is the development of products with fish oil containing triglycerides rich in omega-3 LCPUFA: fish oil as such, encapsulated, microencapsulated or nanoencapsulated. However, independently of such procedures, reversion of taste and odor is always produced, avoiding its consumption. Phospholipids from marine origin are at present a more interesting alternative and of major nutritional impact than triglycerides for supplement omega-3 LCPUFA. These natural products have high concentration of omega-3 LCPUFA, mainly docosahexaenoic acid, are also more stable to oxidation and of higher bioavailability than triglycerides, and in addition provide other nutrients having nutritional benefits. However, at present industrial alternatives to obtain marine phospholipids are limited and probably subjected to future regulations or restrictions. This work analyzes the main advantages of marine phospholipids compared to triglycerides as source of omega-3 LCPUFA, the main sources for these nutrients, such as oils obtained from crustaceous, fish meal or by-products from aquaculture, and the future alternatives to provide the pharmaceutical, nutraceutical and food industry phospholipids from marine origin rich in omega-3 LCPUFA.


El déficit nutricional de ácidos grasos omega-3 de cadena larga (AGPICL omega-3), especialmente de ácido eicosapentaenoico y ácido docosahexaenoico en la población occidental debido al bajo consumo de productos del mar, es motivo actual de preocupación. La alternativa más clásica es el desarrollo de productos que contengan aceite de pescado conteniendo triglicéridos con alto contenido de AGPICL omega-3 en diferentes modalidades; aceite como tal, encapsulado, microencapsulado, o nanoencapsulado. Sin embargo, en cualquiera de estas modalidades, siempre se produce la reversión del olor y sabor, impidiendo así su consumo. Actualmente, los fosfolípidos de origen marino representan una alternativa mucho más interesante y de mayor impacto nutricional para suplementar AGPICL omega-3. Estos productos naturales presentan altas concentraciones de AGPICL omega-3, principalmente de ácido docosahexaenoico, son más estables a la oxidación, de mayor biodisponibilidad que los triglicéridos y además aportan otros nutrientes derivados de su estructura, también beneficiosos para la salud. Sin embargo, las alternativas para la obtención de fosfolípidos marinos a nivel industrial son actualmente pocas y posiblemente sujetas a control o restricción futura. Este trabajo analiza las principales ventajas de los fosfolípidos marinos en relación a los triglicéridos derivados del aceite de pescado como aporte de AGPICL omega-3, las principales fuentes de estos nutrientes, como lo son algunos aceites obtenidos de crustáceos, la harina de pescado o los subproductos de la acuicultura, y las futuras alternativas de desarrollo para proveer a la industria farmacéutica, nutracéutica y de alimentos AGPICL omega-3 a partir de fosfolípidos marinos.


Assuntos
Humanos , Fosfolipídeos , Óleos , Ácidos Graxos Ômega-3 , Recursos Marinhos , Aquicultura , Ciências da Nutrição
2.
Br J Pharmacol ; 166(3): 950-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22122547

RESUMO

BACKGROUND AND PURPOSE: The amphibian peptide Bv8 induces potent nociceptive sensitization in rodents. Its mammalian homologue, prokineticin 2 (PROK2), is strongly up-regulated in inflamed tissues and is a major determinant in triggering inflammatory pain. Bv8 and PROK2 activate two closely related GPCRs, PK(1) and PK(2) , in a relatively non-selective fashion. To characterize better the roles of the two receptors in hyperalgesia and to obtain ligands whose binding affinity and efficacy differed for the two receptors, we modified the Bv8 molecule in regions essential for receptor recognition and activation. EXPERIMENTAL APPROACH: We modified the Bv8 molecule by substituting Trp in position 24 with Ala (A-24) and compared it with Bv8 for binding and activating PK(1) and PK(2) receptors in cell preparations and in affecting nociceptive thresholds in rodents. KEY RESULTS: A-24 preferentially bound to PK(2) receptors and activated them with a lower potency (5-fold) than Bv8. When systemically injected, A-24 induced Bv8-like hyperalgesia in rats and in mice, at doses 100 times higher than Bv8. Locally and systemically injected at inactive doses, A-24 antagonized Bv8-induced hyperalgesia. In rat and mouse models of inflammatory and post-surgical pain, A-24 showed potent and long-lasting anti-hyperalgesic activity. Unlike Bv8, A-24 increased ß-endorphin levels in mouse brain. CONCLUSIONS AND IMPLICATIONS: A-24 induced its anti-hyperalgesic effect in rodents by directly blocking nociceptor PK(1) receptors and by activating the central opioid system and the descending pain control pathway through brain PK(2) receptors.


Assuntos
Proteínas de Anfíbios/química , Proteínas de Anfíbios/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Neuropeptídeos/química , Neuropeptídeos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Alanina/química , Substituição de Aminoácidos , Proteínas de Anfíbios/uso terapêutico , Analgésicos/uso terapêutico , Animais , Células CHO , Quimiotaxia/efeitos dos fármacos , Cricetinae , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Ligantes , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Neuropeptídeos/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/metabolismo , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Transfecção , Triptofano/química
3.
Rev Med Chil ; 139(2): 205-14, 2011 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-21773658

RESUMO

BACKGROUND: Quality indicators are tools used to monitor specific activities within a process and improve it. In the area of clinical laboratories, the National Accreditation Standards for Providers of Health and the ISO 15189 standard recommend the implementation of indicators that monitor the test cycle with emphasis on those that contribute to a safer health care. AIM: To describe the implementation of nine indicators in a hospital clinical laboratory and their measurement during one year. MATERIAL AND METHODS: The indicators implemented and measured were four of the pre-analytical phase (number of rejected samples, times of transport, blood culture contamination and blood cultures inoculated with adequate blood volumes), two of the analytical phase (coherence of Gram stains of blood culture with microorganism cultured and correct results in external quality control surveys) and three of the post-analytical phase (compliance with order to report lapse goals, corrected reports and alert values report). RESULTS: Two indicators of pre-analytical phase did not meet the per determined targets: number of rejected samples and blood cultures inoculated with adequate blood volume. All indicators of the analytical and post analytical phases were within the pre-determined targets. CONCLUSIONS: Coordinated work should be initiated especially with the nursing service to correct the two indicators that did not meet the target. The incorporation of quality indicators to monitor critical processes within the laboratory was undoubtedly an opportunity to identify areas for improvement.


Assuntos
Laboratórios Hospitalares/normas , Indicadores de Qualidade em Assistência à Saúde , Acreditação/organização & administração , Serviço Hospitalar de Emergência/normas , Hospitais Universitários , Humanos , Garantia da Qualidade dos Cuidados de Saúde/normas
4.
Rev. méd. Chile ; 139(2): 205-214, feb. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-595288

RESUMO

Background: Quality indicators are tools used to monitor specific activities within a process and improve it. In the area of clinical laboratories, the National Accreditation Standards for Providers of Health and the ISO 15189 standard recommend the implementation of indicators that monitor the test cycle with emphasis on those that contribute to a safer health care. Aim: To describe the implementation of nine indicators in a hospital clinical laboratory and their measurement during one year. Material and Methods: The indicators implemented and measured were four of the pre-analytical phase (number of rejected samples, times of transport, blood culture contamination and blood cultures inoculated with adequate blood volumes), two of the analytical phase (coherence of Gram stains of blood culture with microorganism cultured and correct results in external quality control surveys) and three of the post-analytical phase (compliance with order to report lapse goals, corrected reports and alert values report). Results: Two indicators of pre-analytical phase did not meet the per determined targets: number of rejected samples and blood cultures inoculated with adequate blood volume. All indicators of the analytical and post analytical phases were within thepre-determined targets. Conclusions: Coordinated work should be initiated especially with the nursing service to correct the two indicators that did not meet the target. The incorporation of quality indicators to monitor critical processes within the laboratory was undoubtedly an opportunity to identify areas for improvement.


Assuntos
Humanos , Laboratórios Hospitalares/normas , Indicadores de Qualidade em Assistência à Saúde , Acreditação/organização & administração , Serviço Hospitalar de Emergência/normas , Hospitais Universitários , Garantia da Qualidade dos Cuidados de Saúde/normas
5.
Ultrasound Obstet Gynecol ; 33(3): 301-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19148891

RESUMO

OBJECTIVE: To evaluate the reliability of two- and three-dimensional ultrasonographic measurement of the thickness of the lower uterine segment (LUS) in pregnant women by transvaginal and transabdominal approaches. METHODS: This was a study of 30 pregnant women who had had at least one previous Cesarean section and were between 36 and 39 weeks' gestation, with singleton pregnancies in cephalic presentation. Sonographic examinations were performed by two observers using both 4-7-MHz transabdominal and 5-8-MHz transvaginal volumetric probes. LUS measurements were performed using two- and three-dimensional ultrasound, evaluating the entire LUS thickness transabdominally and the LUS muscular thickness transvaginally. Each observer measured the LUS four times by each method. Reliability was analyzed by comparing the mean of the absolute differences, the intraclass correlation coefficients, the 95% limits of agreement and the proportion of differences < 1 mm. RESULTS: Transvaginal ultrasound provided greater reliability in LUS measurements than did transabdominal ultrasound. The use of three-dimensional ultrasound improved significantly the reliability of the LUS muscular thickness measurement obtained transvaginally. CONCLUSIONS: Ultrasonographic measurement of the LUS muscular thickness transvaginally appears more reliable than does that of the entire LUS thickness transabdominally. The use of three-dimensional ultrasound should be considered to improve measurement reliability.


Assuntos
Cesárea , Imageamento Tridimensional/métodos , Complicações na Gravidez/diagnóstico por imagem , Ruptura Uterina/diagnóstico por imagem , Útero/diagnóstico por imagem , Adulto , Feminino , Humanos , Imageamento Tridimensional/instrumentação , Variações Dependentes do Observador , Gravidez , Medição de Risco , Ultrassonografia Pré-Natal/métodos , Nascimento Vaginal Após Cesárea , Adulto Jovem
6.
Ultrasound Obstet Gynecol ; 29(2): 210-4, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17201016

RESUMO

OBJECTIVE: To determine the validity and the intra- and interobserver reliability of volume measurements of an endometrium-like model using a three-dimensional (3D) ultrasound rotational technique. METHODS: A 3D ultrasound dataset was obtained from a sample of bovine liver containing a portion of chicken chest muscle (CCM). The process was repeated seven times using pieces of CCM of different sizes, resulting in seven datasets. Each portion of CCM was then placed in a water-filled volume-scaled tube and the 'actual' volumes were calculated by water displacement. For each dataset, ten volumes were calculated by each of two observers using a (VOCAL) with a 15 degrees rotational step. Reliability was assessed by calculating intraclass correlation coefficients (ICC) and validity by examining the percentage difference from the actual volume using limits of agreement. RESULTS: The volume measurement of organic tissues using the 3D ultrasound rotational method was highly reliable (intraobserver ICC, 0.998 for Observer 1 and 0.997 for Observer 2; interobserver ICC, 0.997) and valid (the bias and 95% limits of agreement of the percentage difference from the actual volume was only 0.57 (-3.07 to 4.21) % for Observer 1 and - 0.17 (-4.34 to 4.0) % for Observer 2). CONCLUSIONS: The 3D sonographic measurement, using VOCAL with a 15 degrees rotational step, of small and irregular tissues is reliable and valid, suggesting that it is a useful technique for measurement of the endometrial volume and other volumes of similar size.


Assuntos
Endométrio/diagnóstico por imagem , Imageamento Tridimensional/normas , Ultrassonografia Pré-Natal/normas , Animais , Aves , Bovinos , Galinhas , Feminino , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Fígado , Modelos Biológicos , Músculo Esquelético , Gravidez , Reprodutibilidade dos Testes , Ultrassonografia Pré-Natal/instrumentação , Ultrassonografia Pré-Natal/métodos
7.
Rev. chil. ortop. traumatol ; 46(1): 33-40, 2005. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-410364

RESUMO

El pie paralítico fláccido tiene como deformidades más frecuentes el equino, varo y marcha en "steppage". Existen múltiples tratamientos quirúrgicos. Recientemente, Rodríguez describe una modificación del procedimiento de "Bridle", en el cual el tibial posterior es transferido al dorso del pie, con inserción ósea en la cuña media y tenodesado con el peroneo longus y el tibial anterior, a modo de "rienda" balanceada con tracción en tres puntos. Objetivos: Evaluar el resultado funcional de pacientes con pie paralítico fláccido flexible y semiflexible operados con procedimiento de "Bridle" modificado. Material y método: Evaluación retrospectiva de pacientes con pie paralítico fláccido tratados con técnica de "Bridle" modificado en el Hospital Clínico PUC entre agosto/2000 y abril/2004. Resultados:6 pacientes, 4 hombres y 2 mujeres, con 6 pies operados. Edad promedio de 27,6 (18-37) años. Seguimiento promedio de 26 meses. AOFAS pre/post cirugía: 32/76. Satisfacción completa en todos los pacientes (escala Kenneth-Johnson). Cinco pacientes regresaron a trabajar. Retorno parcial a actividad deportiva en 3 de 4 pacientes. Complicaciones locales en 1 caso; sin complicaciones sistémicas. Conclusión: existen pocas publicaciones sobre este procedimiento; nuestros resultados son comparables con la literatura. El procedimiento de "Bridle" modificado permite obtener un pie funcional, estable y plantígrado, con satisfacción completa en todos los pacientes.


Assuntos
Humanos , Masculino , Feminino , Adulto , Doenças do Pé/cirurgia , Paralisia/cirurgia , Paralisia/etiologia , Transferência Tendinosa , Transferência Tendinosa/métodos
8.
Nucl Med Commun ; 24(3): 305-16, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12612472

RESUMO

We describe in detail the labelling of interleukin-2 with I ( I-IL2), its biochemical characterization, the binding assay and its use for the detection of tissues infiltrated with mononuclear cells. Human recombinant IL2 was labelled using an enzymatic method and its biochemical characterization was performed using high performance liquid chromatography (HPLC) analysis of cyanogen bromide-cleaved protein. biological and binding assays were performed on CTLL-2 cell line and on activated peripheral blood lymphocytes. studies were performed 1 h after administration of 2-3 mCi of I-IL2 in 10 newly diagnosed type 1 diabetes patients, five pre-diabetic patients, 10 Hashimoto's thyroiditis patients, 10 coeliac disease patients and 10 normal volunteers. I-IL2 scintigraphy allowed the detection and quantification of activated mononuclear cells in several affected tissues. In detail, I-IL2 accumulation was detected in the thyroid of all patients affected by Hashimoto's thyroiditis, in the bowel of all coeliac disease patients and in the pancreas of all pre-type 1 diabetic patients. By contrast, in newly diagnosed type 1 diabetics, I-IL2 scan was positive in five of the 10 studied patients. I-IL2 scintigraphy may be useful for studying autoimmune phenomena and in diagnostic protocols to evaluate the presence of other tissue involvement in patients with an organ-specific autoimmune disease.


Assuntos
Doenças Autoimunes/diagnóstico por imagem , Diabetes Mellitus/diagnóstico por imagem , Interleucina-2/farmacocinética , Radioisótopos do Iodo , Linfócitos/diagnóstico por imagem , Adolescente , Adulto , Sequência de Aminoácidos , Doença Celíaca/diagnóstico por imagem , Doença Celíaca/imunologia , Células Cultivadas , Criança , Diabetes Mellitus/imunologia , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Feminino , Humanos , Interleucina-2/química , Marcação por Isótopo/métodos , Contagem de Linfócitos , Masculino , Dados de Sequência Molecular , Valores de Referência , Reprodutibilidade dos Testes , Tireoidite Autoimune/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
9.
Rev. chil. infectol ; 19(3): 167-173, 2002. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-326039

RESUMO

El diagnóstico rápido de microorganismos presentes en fluidos corporales estériles es de gran importancia clínica. La tinción de Gram constituyela principal herramienta para el diagnóstico de estas infecciones, pero la sensibilidad de está técnica varía segín el tipó de muestray la carga bacteriana presente en ella. La concentración de la muestra previa a la tinción, mejora el rendimiento pero requiere volúmenes significativos de la muestra. La citocentrifugación resulta útilya que requiere de escaso volumen de muestra y permite obtener preparaciones uniformemente concentradas. Con el objetivo de evaluar la cito centrifugación en el diagnóstico de fluidos corporales, se estudiaron 52 muestras de fluidos de cavidades estériles recividas en el Laboratorio de Urgencia del Servicio de Laboratorios Clínicos de la Red de Salud UC. Las muestras fueron separadas para centrifugación convencional (CC) a 3000 rpm por 5 minutos (centrifuga Jouan CR3i r) y para citocentrifugación (CT) a 2000 rpm por 10 minutos (Citocentrifuga Cytospin Shandon Inc r). Del sedimento obtenido por CC se realizó un frotis para tición de Gram y cultivo. De la CT se obtuvo una mono capa celular concentrada en un área de 6 mm de diámetro para tinción de Gram. Ambos frotis fueron leídos por el mismo observador. De las 52 muestras analizadas, 18 fueron sugerentes de infección clínica. La sensibilidad para CT v CC fue de 89 por ciento y 61 por ciento, respectivamente. La especificidad fue de 100 por ciento para ambas técnicas. En una evaluación cuantitativa de la celularidad de las muestras, se observó un aumento de los leucocitos en la CT con respecto a CC. Estos resultados muestran que la CT puede ser de gran ayuda en el diagnóstico rápido de las infecciones de fluidos corporales con baja carga bacteriana. Presenta una mayor sensibilidad y facilita la visualización de bacterias, especialmente en muestras con bajo recuento celular


Assuntos
Humanos , Centrifugação/métodos , Líquidos Corporais/microbiologia , Técnicas de Laboratório Clínico , Meios de Cultura , Sensibilidade e Especificidade
11.
Recenti Prog Med ; 92(2): 136-9, 2001 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-11294107

RESUMO

The offspring of patients with premature myocardial infarction are at increased risk for atherosclerosis and its clinical sequelae. High resolution B-mode ultrasonography is considered a reliable method for measuring intima-media thickness of common carotid arteries, a valuable marker of early atherosclerosis. Few recently published studies have evaluated the relationship between familial history of coronary artery disease and carotid intima-media thickness showing that anatomical arterial changes are detectable in subjects with such a history, independently from other well established coronary artery disease risk factors. These findings suggest that carotid intima-media thickness measurement, added to evaluation of classical coronary risk factors, may be useful to better identify high risk subjects.


Assuntos
Artérias/anormalidades , Infarto do Miocárdio/genética , Fatores Etários , Idoso , Humanos , Pessoa de Meia-Idade
12.
Eur J Biochem ; 268(2): 443-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11168381

RESUMO

Genes coding for antimicrobial peptides in amphibia reveal a remarkably high number of structural motifs for response elements, previously identified in the genes of insect antimicrobial peptides and in those of the mammalian acute phase response. This study focuses on the functional analysis of the bombinin gene promoter in a Drosophila blood cell line, and the identification of kappaB-binding factors in skin secretions of the frog Bombina orientalis. Transfection experiments demonstrated that the bombinin gene promoter was activated in a lipopolysaccharide-dependent manner, and that insect Rel factors target specific sequences in the amphibian gene promoter. After bathing frogs in bacteria, their skin secretions contained kappaB-specific binding complexes, indicating that Rel factors are crucial components in the response against gram-negative bacteria in this species. These results suggest that a common ancestral control mechanism governs the expression of the first line host-defence from insects to vertebrates.


Assuntos
Proteínas de Anfíbios , Antibacterianos , Peptídeos Catiônicos Antimicrobianos/genética , Anuros/genética , Proteínas de Drosophila , Proteínas Proto-Oncogênicas c-rel/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Anuros/imunologia , Sítios de Ligação , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Drosophila/citologia , Imunidade Inata , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Transcrição , Células Tumorais Cultivadas
13.
Eur J Biochem ; 268(3): 603-11, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11168399

RESUMO

Two haemoglobin components have been identified and purified from fallow-deer (Dama dama) erythrocytes. They are present in similar amounts and the two tetrameric molecules share the same alpha chain, while two different beta chains are detected in the two components. The beta chains differ by 14 residues, even though they both have 145 amino-acid residues, which account for a molecular mass of 16,023 and 16,064 Da, respectively, while alpha chain has 141 residues, yielding a molecular mass of 15,142 Da. Compared with human Hb, the N-terminal region of both beta chains shows deletion of Val beta 1 and the replacement of His beta 2 by a methionyl residue, a modification which is common to most ruminant haemoglobins. Although both isolated components show a low intrinsic affinity for oxygen, meaningful differences between the two haemoglobins have been found with respect to the effect of heterotropic effectors, such as 2,3-diphosphoglycerate and chloride ions. In view of the high sequence homology between the two components, the different effect of heterotropic ligands has been tentatively correlated to possible localized structural variations between beta chains of the two haemoglobin components.


Assuntos
2,3-Difosfoglicerato/farmacologia , Cloretos/farmacologia , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Sequência de Aminoácidos , Animais , Cloretos/metabolismo , Cromatografia Líquida de Alta Pressão , Cervos , Deleção de Genes , Hemoglobinas/química , Hemoglobinas/genética , Hemoglobinas/isolamento & purificação , Humanos , Ligantes , Dados de Sequência Molecular , Oxigênio/metabolismo , Fosfatos/química , Filogenia , Ligação Proteica , Estrutura Terciária de Proteína , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Software , Temperatura , Fatores de Tempo
14.
Peptides ; 21(11): 1673-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11090921

RESUMO

Skin secretions of amphibia of the Bombina genus contain two families of antimicrobial peptides, the bombinins (bombinin-like peptides) and the bombinins H (H for hydrophobic and hemolytic). The latter family includes a number of peptides containing a D-amino acid in the second position, in addition to their corresponding all L-isomers. The antimicrobial activity of three pairs of bombinin H isomers, H2/H4, H6/H7 and GH-1D/GH-1L, has been investigated. The first two pairs of peptides were actually isolated from the secretion, whereas the third was synthesized according to the sequence deduced from a gene coding for a bombinin-like peptide in Bombina orientalis.


Assuntos
Peptídeos/química , Pele/metabolismo , Aminoácidos/química , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos , Anuros , Membrana Celular/efeitos dos fármacos , Citoplasma/metabolismo , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Peptídeos/metabolismo , Peptídeos/fisiologia , Potássio/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade , Fatores de Tempo , Yersinia pseudotuberculosis/efeitos dos fármacos
15.
Peptides ; 21(11): 1681-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11090922

RESUMO

The structure of a gene coding for bombinin-like peptides (BLP) in Bombina orientalis was determined. It comprises two exons separated by a 1337 bp intron. Exon 1 codes for the signal peptide, while exon 2 contains the genetic information for BLP-7 and a bombinin H-type peptide (GH-2). The promoter region contains putative recognition sites for nuclear factors, such as NF-IL6 and NF-kappaB. The analysis of the structure of this gene, compared with that of the previously reported BLP-3 gene sequence, suggests the occurrence of a gene duplication event, rather than an alternative splicing mechanism, which leads to the generation of both inter- and intra-families variability in this class of cytolytic peptides. Furthermore, chromosome walking analysis indicates that this gene family is not densely clustered.


Assuntos
Proteínas de Anfíbios , Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos/genética , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Anuros , Sequência de Bases , Sítios de Ligação , Southern Blotting , Proteína beta Intensificadora de Ligação a CCAAT/genética , Passeio de Cromossomo , Éxons , Íntrons , Modelos Genéticos , Dados de Sequência Molecular , NF-kappa B/genética , Peptídeos/química , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas , Análise de Sequência de DNA
16.
Protein Expr Purif ; 18(2): 133-40, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10686143

RESUMO

A new papain-like cysteine peptidase isolated from fruits of Pseudananas macrodontes (Morr.) Harms, a species closely related to pineapple (Ananas comosus L.), has been purified and characterized. The enzyme, named macrodontain I, is the main proteolytic component present in fruit extracts and was purified by acetone fractionation followed by anion-exchange chromatography. Separation was improved by selecting both an adequate pH value and a narrow saline gradient. Optimum pH range (more than 90% of maximum activity with casein) was achieved at pH 6.1-8.5. Homogeneity of the enzyme was confirmed by bidimensional electrophoresis and mass spectroscopy (MS). Molecular mass of the enzyme was 23,459 (MS) and its isoelectric point was 6.1. The alanine, glutamine, and tyrosine derivatives were strongly preferred when the enzyme was assayed on N-alpha-CBZ-l-amino acid p-nitrophenyl esters. The N-terminal sequence of macrodontain (by comparison with the N-terminus of 30 plant proteases with more than 50% homology) showed a great deal of sequence similarity to the other pineapple-stem-derived cysteine endopeptidases, being 85.7, 85. 2, and 77.8% identical to comosain, stem bromelain, and ananain, respectively. It seems clear that the Bromeliaceae endopeptidases are more closely related to each other than to other members of the papain family, suggesting relatively recent divergence.


Assuntos
Cisteína Endopeptidases/química , Frutas/química , Sequência de Aminoácidos , Cromatografia por Troca Iônica , Cisteína Endopeptidases/isolamento & purificação , Inibidores de Cisteína Proteinase/química , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Espectrometria de Massas , Dados de Sequência Molecular , Concentração Osmolar , Homologia de Sequência de Aminoácidos
17.
Eur J Biochem ; 267(5): 1447-54, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10691983

RESUMO

Temporins, antimicrobial peptides of 10-13 residues, were isolated from secretions of Rana temporaria [Simmaco, M., Mignogna, G., Canofeni, S., Miele, R., Mangoni, M.L. & Barra, D. (1996) Eur. J. Biochem. 242, 788-792]. These molecules are specific to this amphibian species, which is also able to secrete on its skin other antimicrobial peptides similar to those found in different Rana species. The effect of temporins A, B and D (13 residues, net charge +2), and H (10 residues, net charge +1 and +2, respectively) against both artificial membranes of differing lipid composition and bacteria has been investigated in order to gain insight into their mechanisms of action. The results indicate that: the lytic activity of temporins is not greatly affected by the membrane composition; temporins A and B allow the leakage of large-size molecules from the bacterial cells; temporin H renders both the outer and inner membrane of bacteria permeable to hydrophobic substances of low molecular mass; and temporin D, although devoid of antibacterial activity, has a cytotoxic effect on erythrocytes. The results allow important conclusions to be drawn about the minimal structural requirements for lytic efficiency and specificity of temporins.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos , Sequência de Aminoácidos , Animais , Dicroísmo Circular , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Fosfolipídeos/química , Rana temporaria , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Infect Immun ; 68(2): 694-701, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639435

RESUMO

In the search of the antigenic determinants of a 65-kDa mannoprotein (MP65) of Candida albicans, tryptic fragments of immunoaffinity-purified MP65 preparations were tested for their ability to induce lymphoproliferation of human peripheral blood mononuclear cells (PBMC). Five major peptides (T1 to T5) were shown to induce a vigorous proliferation of PBMC from the majority of the eight healthy human subjects tested. With the use of synthetic peptides, critical amino acid sequences of the two most immunoactive (T1 and T2) peptides were determined. Similar to what was found for the MP65 molecule, no PBMC multiplication was induced by the antigenic peptides in cultures of naive cord blood cells. The amino acid sequence analysis of tryptic and chymotryptic peptides of MP65 demonstrated a substantial homology with the deduced sequences of two cell wall proteins of Saccharomyces cerevisiae, encoded by the genes YRM305C and YGR279C. However, the antigenic peptides were those showing the least similarity with the corresponding regions of the above proteins. In particular, the lymphoproliferation-inducing sequence of the T1 peptide scored only 20% identity with the homologous regions of S. cerevisiae proteins. Besides disclosing the amino acid sequence of MP65, this study provides an initial characterization of some of its antigenic determinants, as well as of synthetic peptides of potential use to detect specific immune responses against MP65, a major target of anticandidal cell-mediated immunity in humans.


Assuntos
Antígenos de Fungos/imunologia , Candida albicans/imunologia , Proteínas Fúngicas/imunologia , Glicoproteínas de Membrana/imunologia , Sequência de Aminoácidos , Animais , Humanos , Ativação Linfocitária , Glicoproteínas de Membrana/isolamento & purificação , Glicoproteínas de Membrana/metabolismo , Camundongos , Dados de Sequência Molecular
19.
Rev. chil. infectol ; 17(2): 101-8, 2000. tab
Artigo em Espanhol | LILACS | ID: lil-269400

RESUMO

La infección osteoarticular (IOA) es una patología grave y secuelante, en la que el diagnóstico precoz cambia el curso de la enfermedad. El rendimiento del estudio microbiológico es variable (60-90 porciento) y depende de la localización de la infección, el tipo de muestra y los métodos microbiológicos utilizados. El objetivo de este estudio fue mejorar la confirmación bacteriológica mediante una solicitud ampliada de cultivos y de nuevas estrategias para el transporte e inoculación de las muestras. Se estudiaron los pacientes con sospecha de IAO mediante tinción de gram directa y cultivos aeróbico, en medio de thayer martin, anaeróbico, para hongos, micobacterias y hemocultivos. Todas las muestras de líquido sinovial se inocularon en tubos microbiológicos (becton dickinson) y las muestras de tejido obtenidas por punción bajo tomografía axial computada (tac) fueron innoculadas en botellas de hemocultivos (bact/aler@, organon teknica). Se estudiaron 86 pacientes de los cuales 51 correspondían al ioa. El rendimiento microbiológico global fue de 86 porciento, siendo más alto en osteomielitis aguda e infección de prótesis que en artritis séptica (88, 100 y 82 porciento respectivamente). Staphylococcus aureus fue el patógeno más prevalente, independiente del tipo de ioa, seguido de streptococcus pyogenes y streptococcus pneumoniae. La tinción de gram directa tuvo una sensibilidad de 57 porciento y en 5 pacientes cuyos cultivos fueron negativos, fue positiva. Los hemocultivos fueron positivos como método único en 6 pacientes. La sensibilidad del cultivo de tejido obtenido por punción bajo tac en botella de hemocultivo fue de 90 porciento. La posibilidad del cultivo de muestra de tejido óseo o sinovial fue mejor que la de líquido articular (92 versus 69 porciento) y la confirmación microbiológica global fue mejor en adultos que en niños (94 y 72 porciento respectivamente). Se concluye que la implementación de tubos microbiológicos y la inoculación directa en la botella de hemocultivo son métodos útiles para la recuperación bacteriana. La muestra de tejido debe ser recomendada antes que la de líquido articular y la tinción de gram y el hemocultivo deben ser considerados como métodos de gran aporte en la confirmación microbiológica de las IOA


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Adolescente , Adulto , Pessoa de Meia-Idade , Doenças Ósseas Infecciosas/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Artrite Infecciosa/microbiologia , Infecções Bacterianas/etiologia , Líquido Sinovial/microbiologia , Osteomielite/microbiologia
20.
FEBS Lett ; 461(3): 149-52, 1999 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-10567687

RESUMO

Pantetheinase is an amidohydrolase involved in the dissimilative pathway of CoA, allowing the turnover of the pantothenate moiety. We have determined the N-terminal sequence as well as the sequences of a number of tryptic and chymotryptic peptides of the protein isolated from pig kidney. These sequence stretches were used as probes to search in the SwissProt database and significant similarities were found with a GPI-anchored protein (mouse vanin-1, with a suggested role in lymphocyte migration), with two putative proteins encoded by human cDNAs (VNN1 and VNN2) and with human biotinidase. On the basis of sequence similarity, we propose that vanin-1 and VNN1 should be identified as pantetheinase.


Assuntos
Amidoidrolases/química , Moléculas de Adesão Celular/química , Sequência de Aminoácidos , Animais , Biotinidase , Proteínas Ligadas por GPI , Humanos , Hidrolases , Rim/enzimologia , Camundongos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Suínos
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