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1.
Biochim Biophys Acta ; 1861(9 Pt A): 970-979, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27233517

RESUMEN

Brown spider phospholipases D from Loxosceles venoms are among the most widely studied toxins since they induce dermonecrosis, triggering inflammatory responses, increase vascular permeability, cause hemolysis, and renal failure. The catalytic (H12 and H47) and metal-ion binding (E32 and D34) residues in Loxosceles intermedia phospholipase D (LiRecDT1) were mutated to understand their roles in the observed activities. All mutants were identified using whole venom serum antibodies and a specific antibody to wild-type LiRecDT1, they were also analyzed by circular dichroism (CD) and differential scanning calorimetry (DSC). The phospholipase D activities of H12A, H47A, H12A-H47A, E32, D34 and E32A-D34A, such as vascular permeability, dermonecrosis, and hemolytic effects were inhibited. The mutant Y228A was equally detrimental to biochemical and biological effects of phospholipase D, suggesting an essential role of this residue in substrate recognition and binding. On the other hand, the mutant C53A-C201A reduced the enzyme's ability to hydrolyze phospholipids and promote dermonecrosis, hemolytic, and vascular effects. These results provide the basis understanding the importance of specific residues in the observed activities and contribute to the design of synthetic and specific inhibitors for Brown spider venom phospholipases D.


Asunto(s)
Dominio Catalítico/genética , Fosfolipasa D/química , Fosfolípidos/química , Venenos de Araña/enzimología , Animales , Araña Reclusa Parda/química , Araña Reclusa Parda/enzimología , Permeabilidad Capilar , Dicroismo Circular , Hemólisis , Mutación , Fosfolipasa D/metabolismo , Fosfolípidos/metabolismo , Hidrolasas Diéster Fosfóricas/química , Venenos de Araña/química
2.
Toxicon ; 98: 62-74, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25720299

RESUMEN

This is the first study on the hemolymph from a spider of the Loxosceles genus. These animals are responsible for a great number of envenomation cases worldwide. Several studies on Loxosceles venoms have been published, and the knowledge about the venom and its toxins is considerable, not only regarding the biological and biochemical characterization, but also regarding structural, genetic and phylogenetic approaches. However, the literature on Loxosceles hemolymph is nonexistent. The main goal of the present study was to characterize biochemically the hemolymph content, and especially, to identify its different hemocytes. Moreover, many papers have already shown molecules whose source is the hemolymph and their very interesting activities and biomedical applications, for example, antifungal and antibacterial activities. A 2D-SDS-PAGE of brown spider hemolymph showed approximately 111 spots for pH 3-10 and 150 spots for pH 4-7. A lectin-blotting assay showed that hemolymph carbohydrate residues were similar to those found in venom. Several types of TAG and DAG phospholipids were found in the hemolymph and characterized by HPTLC and mass spectrometry. Four different hemocytes were characterized in Loxosceles intermedia hemolymph: prohemocyte, plasmatocyte, granulocyte and adipohemocyte. This paper opens new possibilities on toxinology, studying an unknown biological material, and it characterizes a source of molecules with putative biotechnological applications.


Asunto(s)
Araña Reclusa Parda , Hemolinfa/química , Hidrolasas Diéster Fosfóricas/química , Venenos de Araña/química , Animales , Mordeduras y Picaduras/patología , Cromatografía en Capa Delgada , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Filogenia
3.
Arq. bras. med. vet. zootec ; 63(3): 584-590, June 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-595573

RESUMEN

The occurrence of proteocephalid cestodes in tucunaré Cichla sp., captured monthly, between August 2000 and August 2001, in Paraná River, Presidente Epitácio, SP, was evaluated. From 128 specimens, 71 (55.6 percent) were parasitized by Proteocephalus macrophallus (Diesing, 1850) and/or P. microscopicus (Woodland, 1935). Total mean abundance and intensity were 157.08 and 223.41, respectively. The highest prevalence (90 percent) mean abundance (1,122.4) and intensity indexes (1,247.11) occurred in February 2001, while in September 2000 there were no observed animals infected by cestodes. No relationship between the sex of the host and parasitological indexes was found.


Avaliou-se a ocorrência de cestóides proteocefalídeos em tucunaré Cichla sp., capturados mensalmente, entre agosto de 2000 e agosto de 2001, no rio Paraná, em Presidente Epitácio, SP. Um total de 128 espécimes foram analisados, dos quais 71 (55,6 por cento) estavam parasitados por Proteocephalus macrophallus (Diesing, 1850) e/ou P. microscopicus (Woodland, 1935). A abundância e intensidade média total foram de 157,08 e 223,41, respectivamente. A maior prevalência (90 por cento), juntamente com os maiores índices de abundância (1122,4) e intensidade média (1247,11) ocorreram no mês de fevereiro 2001, enquanto no mês de setembro 2000 não foram observados animais parasitados por cestóides. Não houve relação entre o sexo do hospedeiro e os índices parasitológicos.


Asunto(s)
Animales , Interacciones Huésped-Parásitos , Infecciones por Cestodos/veterinaria , Enfermedades Parasitarias , Peces
4.
Br J Pharmacol ; 161(1): 229-40, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20718752

RESUMEN

BACKGROUND AND PURPOSE Advanced glycation end products (AGEs) subtypes, proteins or lipids that become glycated after exposure to sugars, can induce complications in diabetes. Among the various AGE subtypes, glyceraldehyde-derived AGE (AGE-2) and glycolaldehyde-derived AGE (AGE-3) are involved in inflammation in diabetic patients; monocytes are activated by these AGEs. Ciprofloxacin (CIP), a fluorinated 4-quinolone, is often used clinically to treat infections associated with diabetis due to its antibacterial properties. It also modulates immune responses in human peripheral blood mononuclear cells (PBMC) therefore we investigated the involvement of AGEs in these effects. EXPERIMENTAL APPROACH Expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2 and CD40 was examined by flow cytometry. The production of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, prostaglandin E(2) (PGE(2)) and cAMP were determined by enzyme-linked immunosorbent assay. Cyclooxygenase (COX)-2 expression was determined by Western blot analysis. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake. KEY RESULTS CIP induced PGE(2) production in monocytes, irrespective of the presence of AGE-2 and AGE-3, by enhancing COX-2 expression; this led to an elevation of intracellular cAMP in monocytes. Non-selective and selective COX-2 inhibitors, indomethacin and NS398, inhibited CIP-induced PGE(2) and cAMP production. In addition, CIP inhibited AGE-2- and AGE-3-induced expressions of ICAM-1, B7.1, B7.2 and CD40 in monocytes, the production of TNF-alpha and IFN-gamma and lymphocyte proliferation in PBMC. Indomethacin, NS398 and a protein kinase A inhibitor, H89, inhibited the actions of CIP. CONCLUSIONS AND IMPLICATIONS CIP exerts immunomodulatory activity via PGE(2), implying therapeutic potential of CIP for the treatment of AGE-2- and AGE-3-induced inflammatory responses.


Asunto(s)
Antibacterianos/farmacología , Moléculas de Adhesión Celular/metabolismo , Ciprofloxacina/farmacología , Regulación de la Expresión Génica/fisiología , Productos Finales de Glicación Avanzada/farmacología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Moléculas de Adhesión Celular/efectos de los fármacos , Proliferación Celular , AMP Cíclico/metabolismo , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dinoprostona/metabolismo , Humanos , Linfocitos/citología , Linfocitos/fisiología
5.
Br J Pharmacol ; 160(6): 1378-86, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20590628

RESUMEN

BACKGROUND AND PURPOSE: Post-transplant diabetes mellitus is a frequent complication among transplant recipients. Ligation of advanced glycation end products (AGEs) with their receptor on monocytes/macrophages plays important roles in the genesis of diabetic complications. The enhancement of adhesion molecule expression on monocytes/macrophages activates T-cells, reducing allograft survival. Out of four distinct AGE subtypes (AGE-2, AGE-3, AGE-4 and AGE-5), only AGE-2 and AGE-3 induced expression of intercellular adhesion molecules (ICAMs), output of cytokines and proliferation of lymphocytes, during the mixed lymphocyte reaction (MLR). Here we have assessed the role of histamine in the actions of AGEs during the MLR. EXPERIMENTAL APPROACH: Human peripheral blood cells were used in these experiments. Flow cytometry was used to examine the expression of the ICAM-1, B7.1, B7.2 and CD40. Production of the cytokine interferon-gamma, and levels of cAMP were determined by elisa. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake. KEY RESULTS: Histamine concentration dependently inhibited the action of AGE-2 and AGE-3. The actions of histamine were antagonized by an H(2)-receptor antagonist, famotidine, and mimicked by H(2)/H(4)-receptor agonists, dimaprit and 4-methylhistamine. The effects of histamine were reversed by a protein kinase A (PKA) inhibitor, H89, and mimicked by dibutyryl cAMP and an adenylate cyclase activator, forskolin. CONCLUSIONS AND IMPLICATIONS: Histamine down-regulated AGE-2- and AGE-3-induced expression of adhesion molecules, cytokine production and lymphocyte proliferation via histamine H(2) receptors and the cAMP/PKA pathway.


Asunto(s)
Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Histamina/farmacología , Molécula 1 de Adhesión Intercelular/genética , Proliferación Celular/efectos de los fármacos , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Histamina/administración & dosificación , Humanos , Interferón gamma/metabolismo , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Receptores Histamínicos H2/efectos de los fármacos , Receptores Histamínicos H2/metabolismo
6.
Braz. j. med. biol. res ; 42(9): 844-853, Sept. 2009. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-524316

RESUMEN

Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR) and normotensive control rat strains (WKY and NWR). Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.


Asunto(s)
Animales , Masculino , Ratas , Aorta/química , Membrana Celular/química , Colesterol/análisis , Hipertensión/metabolismo , Arterias Mesentéricas/química , Fosfolípidos/análisis , Colesterol/química , Espectroscopía de Resonancia por Spin del Electrón , Cromatografía de Gases y Espectrometría de Masas , Hipertensión/etiología , Músculo Liso Vascular/química , Músculo Liso Vascular/citología , Fosfolípidos/química , Ratas Endogámicas SHR , Ratas Endogámicas WKY
7.
Braz J Med Biol Res ; 42(9): 844-53, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19649392

RESUMEN

Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR) and normotensive control rat strains (WKY and NWR). Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.


Asunto(s)
Aorta/química , Membrana Celular/química , Colesterol/análisis , Hipertensión/metabolismo , Arterias Mesentéricas/química , Fosfolípidos/análisis , Animales , Colesterol/química , Espectroscopía de Resonancia por Spin del Electrón , Cromatografía de Gases y Espectrometría de Masas , Hipertensión/etiología , Masculino , Músculo Liso Vascular/química , Músculo Liso Vascular/citología , Fosfolípidos/química , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
8.
Curr Oncol ; 14(6): 246, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18080017
9.
Braz J Med Biol Res ; 40(6): 799-806, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17581678

RESUMEN

The role of glycosphingolipids (GSLs) present in amastigote forms of Leishmania (Leishmania) amazonensis during infection of macrophages was analyzed, with particular emphasis on GSLs presenting the terminal Galpss1-3Galpa disaccharide. Macrophage invasion by L. (L.) amazonensis amastigotes was reduced by 37% when the disaccharide Galpss1-3Galp (1 mM) was added to the culture medium. The putative macrophage receptor/lectin for ss-Gal-globotriaosylceramide (Galpss1-3Galpa1-4Galpss1-4Glc pss1-1Cer) and other structurally related GSLs from L. (L.) amazonensis amastigotes were analyzed by micelles and parasite binding assay to peritoneal macrophage proteins fractionated by SDS-PAGE under nonreducing conditions. Micelles containing purified amastigote GSLs or a suspention of L. (L.) amazonensis amastigotes fixed with 2% formaldehyde were incubated with nitrocellulose membrane containing the macrophage proteins transferred by Western blotting. Binding of micelles containing purified GSLs from amastigote forms or fixed L. (L.) amazonensis amastigotes to nitrocellulose membrane was probed using monoclonal antibody ST-3, which recognizes the glycoepitope Galpss1-3Galpa1-R present either in the micelle preparation or on the amastigote surface. Macrophage protein with molecular mass ~30 kDa bound the amastigote GSL and appeared to be a doublet on electrophoresis. The specificity of this interaction was confirmed using fixed L. (L.) chagasi amastigotes, which do not express GSLs such as ss-Galp-globotriaosylceramides, and which do not bind to 30-kDa protein.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Glicoesfingolípidos/metabolismo , Leishmania mexicana/metabolismo , Macrófagos/parasitología , Animales , Western Blotting , Cricetinae , Electroforesis en Gel de Poliacrilamida , Glicoesfingolípidos/inmunología , Leishmania mexicana/inmunología , Leishmania mexicana/patogenicidad , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C
10.
Braz. j. med. biol. res ; 40(6): 799-806, June 2007. graf, tab
Artículo en Inglés | LILACS | ID: lil-452683

RESUMEN

The role of glycosphingolipids (GSLs) present in amastigote forms of Leishmania (Leishmania) amazonensis during infection of macrophages was analyzed, with particular emphasis on GSLs presenting the terminal Galpß1-3Galpa disaccharide. Macrophage invasion by L. (L.) amazonensis amastigotes was reduced by 37 percent when the disaccharide Galpß1-3Galp (1 mM) was added to the culture medium. The putative macrophage receptor/lectin for ß-Gal-globotriaosylceramide (Galpß1-3Galpa1-4Galpß1-4Glc pß1-1Cer) and other structurally related GSLs from L. (L.) amazonensis amastigotes were analyzed by micelles and parasite binding assay to peritoneal macrophage proteins fractionated by SDS-PAGE under nonreducing conditions. Micelles containing purified amastigote GSLs or a suspention of L. (L.) amazonensis amastigotes fixed with 2 percent formaldehyde were incubated with nitrocellulose membrane containing the macrophage proteins transferred by Western blotting. Binding of micelles containing purified GSLs from amastigote forms or fixed L. (L.) amazonensis amastigotes to nitrocellulose membrane was probed using monoclonal antibody ST-3, which recognizes the glycoepitope Galpß1-3Galpa1-R present either in the micelle preparation or on the amastigote surface. Macrophage protein with molecular mass ~30 kDa bound the amastigote GSL and appeared to be a doublet on electrophoresis. The specificity of this interaction was confirmed using fixed L. (L.) chagasi amastigotes, which do not express GSLs such as ß-Galp-globotriaosylceramides, and which do not bind to 30-kDa protein.


Asunto(s)
Animales , Cricetinae , Ratones , Anticuerpos Monoclonales/inmunología , Glicoesfingolípidos/metabolismo , Leishmania mexicana/metabolismo , Macrófagos/parasitología , Western Blotting , Electroforesis en Gel de Poliacrilamida , Glicoesfingolípidos/inmunología , Leishmania mexicana/inmunología , Leishmania mexicana/patogenicidad , Ratones Endogámicos BALB C , Macrófagos/inmunología
11.
Br J Pharmacol ; 150(6): 816-22, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17310143

RESUMEN

BACKGROUND AND PURPOSE: Adenosine suppresses immune responses through adenosine(2A) (A(2A)) receptors, by raising intracellular cAMP. Interleukin (IL)-18 up-regulates the expression of intercellular adhesion molecule (ICAM)-1 on monocytes, leading to production of pro-inflammatory cytokines such as IL-12, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha by human peripheral blood mononuclear cells (PBMC). We have previously demonstrated that elevation of cAMP inhibits this IL-18-induced expression of adhesion molecules. In the present study, we examined the effect of adenosine on the IL-18-induced up-regulation of ICAM-1 on human monocytes and production of IL-12, IFN-gamma and TNF-alpha by PBMC. EXPERIMENTAL APPROACH: The expression of ICAM-1 was examined by flow cytometry. IL-12, IFN-gamma and TNF-alpha were determined by ELISA assay. KEY RESULTS: Adenosine inhibited the IL-18-induced up-regulation of ICAM-1 on human monocytes and it abolished the IL-18-enhanced production of IL-12, IFN-gamma and TNF-alpha. While an A(2A) receptor antagonist reversed the action of adenosine, an A(1) or A(3) receptor antagonist enhanced them. An A(2A) receptor agonist, CGS21680, mimicked the effects of adenosine and its effects were abolished not only by the A(2A) receptor antagonist but also by A(1) or A(3) receptor agonists. Activation via A(2A) receptors resulted in elevation of cAMP in monocytes, whereas the stimulation of A(1) or A(3) receptors inhibited it, suggesting that intracellular signal transduction following ligation of A(2A) receptors might be blocked by activation of A(1) or A(3) receptors. CONCLUSIONS AND IMPLICATIONS: Adenosine differentially regulates IL-18-induced adhesion molecule expression and cytokine production through several subtypes of its receptors.


Asunto(s)
Adenosina/farmacología , Citocinas/biosíntesis , Molécula 1 de Adhesión Intercelular/metabolismo , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Receptores Purinérgicos P1/efectos de los fármacos , Agonistas del Receptor de Adenosina A1 , Antagonistas del Receptor de Adenosina A1 , Agonistas del Receptor de Adenosina A2 , Antagonistas del Receptor de Adenosina A2 , Agonistas del Receptor de Adenosina A3 , Antagonistas del Receptor de Adenosina A3 , Adulto , Anciano , Femenino , Humanos , Técnicas In Vitro , Interferón gamma/biosíntesis , Interleucina-12/biosíntesis , Interleucina-18/farmacología , Masculino , Persona de Mediana Edad , Receptor de Adenosina A1/metabolismo , Receptor de Adenosina A2A/metabolismo , Receptor de Adenosina A2B/metabolismo , Receptor de Adenosina A3/metabolismo , Receptores Purinérgicos P1/clasificación , Receptores Purinérgicos P1/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis
12.
Parasitology ; 131(Pt 6): 737-45, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16336727

RESUMEN

Specific glycolipids (GLs) from Leishmania (Viannia) braziliensis promastigotes were isolated and purified. A monoclonal antibody directed to carbohydrate epitopes of these GLs was produced. mAb SST-1 recognizes a low molecular weight GL as established by solid-phase radioimmunoassay and HPTLC immunostaining, and does not cross-react with lipophosphoglycan isolated from L. (V.) braziliensis promastigotes. An indirect immunofluorescence study indicated that the antigenic GLs are present at the L. (V.) braziliensis promastigote surface. SST-1 reacted with promastigotes of L. (V.) naiffi and L. (V.) guyanensis, but not with species in the L. Leishmania subgenus i.e. L. (L.) amazonensis, L. (L.) chagasi, or L. (L.) major. All L. (V.) braziliensis serodemes tested were reactive with SST-1. These results indicate that SST-1 recognizes specific GLs expressed by species of the Viannia subgenus, and will be particularly useful for identification of L. (V.) braziliensis.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Protozoos/aislamiento & purificación , Glucolípidos/aislamiento & purificación , Leishmania braziliensis/inmunología , Ratones/inmunología , Ratones/parasitología , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Antiprotozoarios/biosíntesis , Anticuerpos Antiprotozoarios/inmunología , Especificidad de Anticuerpos/inmunología , Antígenos de Protozoos/inmunología , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Glucolípidos/inmunología , Humanos , Fragmentos Fab de Inmunoglobulinas/inmunología , Leishmania braziliensis/patogenicidad , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/parasitología , Ratones Endogámicos BALB C , Fagocitosis , Radioinmunoensayo , Especificidad de la Especie
13.
Vet Parasitol ; 134(1-2): 111-5, 2005 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-16112458

RESUMEN

This work evaluated parasitic infections by Neoechinorhynchus curemai (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus captured between August 2000 and August 2001 in the Paraná River, Presidente Epitácio, São Paulo, Brazil. Of 87 fishes examined, 59 were infected (25 males and 34 females). High mean intensities occurred in August 2000 (45.2, range 2-204), September 2000 (28.5, range 11-73), October 2000 (59.3, range 2-250) and February 2001 (27.3, range 3-73). There was no relationship of rainfall with mean intensity and prevalence. Males were more parasitized (P<0.05) than females. This work contributes to the knowledge of helminth parasites of fish from a little studied region of the Paraná River, showing diversity in their fauna when compared to other places in the same river.


Asunto(s)
Acantocéfalos/crecimiento & desarrollo , Enfermedades de los Peces/parasitología , Animales , Brasil , Femenino , Masculino , Prevalencia , Lluvia , Ríos , Estaciones del Año , Estadísticas no Paramétricas
14.
J Int Med Res ; 32(5): 465-83, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15458278

RESUMEN

We examined the effects of beta2-adrenergic receptor (beta2-AR) agonists on the expression of co-stimulatory molecules on lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells. The study found that beta2-AR agonists inhibited the expression of intercellular adhesion molecule-1 (ICAM-1), CD40 and CD14 on monocytes, and that AR agonist activity was antagonized by the selective beta2-AR antagonist, butoxamine. The selective beta2-AR agonists salbutamol and terbutaline induced a similar co-stimulatory molecule expression pattern. The LPS-induced production of tumour necrosis factor-alpha was inhibited by AR agonists, and this was also antagonized by butoxamine, and mimicked by salbutamol and terbutaline. The AR agonists also inhibited T-cell proliferation through beta2-AR stimulation. This study clearly demonstrated that endogenous catecholamines elicited immunosuppressive effects through beta2-AR stimulation, possibly due to down-regulation of the expression of ICAM-1, CD40 and CD14 on monocytes. These results suggested that the sympathetic nervous system might regulate the T-helper cell balance via the peripheral end-effectors of the stress system.


Asunto(s)
Antígenos CD40/metabolismo , Tolerancia Inmunológica , Molécula 1 de Adhesión Intercelular/metabolismo , Receptores de Lipopolisacáridos/metabolismo , Monocitos/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Agonistas de Receptores Adrenérgicos beta 2 , Antagonistas de Receptores Adrenérgicos beta 2 , Albuterol/farmacología , Butoxamina/farmacología , Proliferación Celular , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Humanos , Lipopolisacáridos/farmacología , Glicoproteínas de Membrana/metabolismo , Monocitos/efectos de los fármacos , Receptores de Superficie Celular/metabolismo , Linfocitos T/inmunología , Linfocitos T/fisiología , Terbutalina/farmacología , Receptores Toll-Like , Factor de Necrosis Tumoral alfa/metabolismo
15.
Inflamm Res ; 53(4): 164-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15060723

RESUMEN

OBJECTIVE AND DESIGN: Carboxymethylcellulose (CMC) has been considered to be inert and is commonly used as an additive in medicines, foods and cosmetics. However, we experienced a patient who developed an anaphylactic reaction to CMC after an upper gastrointestinal examination using a barium meal containing CMC. Therefore, we examined the incidence of sensitization by CMC in healthy subjects, and categorized the high risk group prone to developing anaphylactic response to CMC. METHODS: An ELISA for detecting CMC-specific IgE antibody was developed using serum from the patient as a positive control. In the ten subjects exhibiting high anti-CMC IgE among 387 normal populations, histamine release from isolated leukocytes was performed. RESULTS: Five of ten subjects with a high IgE titer showed a significant CMC-induced histamine release from leukocyte preparations in vitro as observed in the patient, and were classified as high risk group. There was a correlation between sensitization by CMC and that by Japanese cedar pollen. The incidence of sensitization in females was 2.4 fold higher than that in males. CONCLUSIONS: The combination of ELISA and histamine release experiment made it possible to identify the high risk group for developing anaphylactic response. The administration of high dose CMC as a suspending agent in barium sulfate or injectable corticosteroids to this group should be avoided to prevent anaphylactic reactions in the clinic.


Asunto(s)
Anafilaxia/etiología , Carboximetilcelulosa de Sodio/efectos adversos , Liberación de Histamina/efectos de los fármacos , Inmunoglobulina E/sangre , Adulto , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad
16.
J Int Med Res ; 32(1): 25-32, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14997702

RESUMEN

Co-stimulatory molecules play important roles in immune responses. We investigated the effect of Bu-Zhong-Yi-Qi-Tang (TJ-41) on the expression of intercellular adhesion molecule-1 (ICAM-1), B7.1 and B7.2 by peripheral blood mononuclear cells stimulated by interleukin-18 (IL-18) using fluorescence-activated cell sorter analysis. TJ-41 increased IL-18-induced ICAM-1 and B7.2 expression, resulting in enhanced production of tumour necrosis factor-alpha and interferon-gamma. These results suggest that TJ-41 enhances IL-18-induced cell-mediated immunity and may enhance host defence mechanisms against pathogens.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Interferón gamma/biosíntesis , Interleucina-1/farmacología , Monocitos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis , Antígenos CD/metabolismo , Antígeno B7-2 , Citometría de Flujo , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Lipopolisacáridos/farmacología , Glicoproteínas de Membrana/metabolismo , Monocitos/metabolismo
17.
Parasitology ; 127(Pt 5): 449-56, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14653534

RESUMEN

The immunolocalization of Leishmania (Viannia) braziliensis stage-specific antigens recognized by mAbs was analysed by transmission electron microscopy. The antigen recognized by mAb SST-2 was present at the surface of promastigotes, including the flagellum and flagellar pocket. The reactivity of SST-2 with isolates of different serodemes showed a pronounced microheterogeneity in terms of the number of reactive bands within the low molecular weight range from 24 to 33 kDa. The 180 kDa glycoprotein recognized by mAb SST-3 was present only in the flagellar membrane. SST-3 also recognized multiple discrete bands from 160 to 200 kDa, as observed in several serodemes. In contrast, mAb SST-4, which recognizes a 98 kDa antigen, showed weak labelling on the promastigote surface by transmission electron microscopy and indirect immunofluorescence. Based on Western blotting, indirect immunofluorescence, and solid-phase radioimmunoassay, the antigens recognized by mAbs SST-2, SST-3 and SST-4 were present in all L. (V.) braziliensis analysed, from 7 different serodemes.


Asunto(s)
Antígenos de Protozoos/inmunología , Leishmania braziliensis/inmunología , Proteínas de la Membrana/inmunología , Animales , Anticuerpos Monoclonales , Antígenos de Protozoos/metabolismo , Western Blotting , Técnica del Anticuerpo Fluorescente Indirecta , Proteínas de la Membrana/metabolismo , Microscopía Electrónica , Radioinmunoensayo
19.
J Int Med Res ; 30(2): 144-60, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12025522

RESUMEN

Interleukin (IL) 18, a powerful inducer of the immunoregulatory cytokine interferon-gamma (IFN-gamma), presents upstream of the cytokine activation cascade in the inflammatory response. The anti-inflammatory properties of steroids permit their use in various conditions, although effects are transient and pathological states are not fully relieved by short-term steroidal use. We examined the effect of lipopolysaccharide (LPS)/IL-2 on the cytokine cascade in human peripheral blood mononuclear cells (PBMCs). We also examined the effect of steroids on LPS/IL-2-induced cytokine production in human PBMCs taken from healthy volunteers. Cell-free supernatant fractions were assayed for IL-18, IL-12, IL-2, IFN-gamma and IL-10 protein, using enzyme-linked immunosorbent assays, and synergy between LPS and IL-2 in enhanced production of IL-18 was observed. Steroids suppressed the production of IL-18 and other secondary cytokines in LPS/IL-2-stimulated PBMCs, in a concentration- and time-dependent manner, although inhibition was incomplete even at high concentrations. Effects of steroid treatment on expression of membrane-bound LPS receptor antigen (mCD14) and intercellular adhesion molecule-1 (ICAM-1) in PBMCs were studied by flow cytometric analysis. Steroid treatment up-regulated mCD14 expression in a concentration-dependent manner, with no effect on ICAM-1 expression. These results suggest that the incomplete counteraction of steroids in the LPS/IL-2-initiating cytokine cascade is due, at least partly, to the up-regulation of mCD14 by steroid preparations, which increases susceptibility to bacterial endotoxins.


Asunto(s)
Hidrocortisona/análogos & derivados , Hidrocortisona/farmacología , Interleucina-18/metabolismo , Interleucina-2/inmunología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Lipopolisacáridos/inmunología , Hemisuccinato de Metilprednisolona/farmacología , Animales , Antiinflamatorios/farmacología , Anticuerpos Monoclonales/metabolismo , Células Cultivadas , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-18/inmunología , Interleucina-2/metabolismo , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Receptores de Lipopolisacáridos/metabolismo , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Transducción de Señal/fisiología
20.
Rapid Commun Mass Spectrom ; 15(23): 2240-58, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11746891

RESUMEN

Glycosylinositol phosphorylceramides (GIPCs) are a class of acidic glycosphingolipids (GSLs) expressed by fungi, plants, and certain parasitic organisms, but not found in cells or tissues of mammals or other higher animals. Recent characterizations of fungal GIPCs point to an emerging diversity which could rival that already known for mammalian GSLs, and which can be expected to present a multitude of challenges for the analytical chemist. Previously, the use of Li(+) cationization, in conjunction with electrospray ionization mass spectrometry (ESI-MS) and low-energy collision-induced dissociation tandem mass spectrometry (ESI-MS/CID-MS), was found to be particularly effective for detailed structural analysis of monohexosylceramides (cerebrosides) from a variety of sources, including fungi, especially minor components present in mixtures at extremely low abundance. In applying Li(+) cationization to characterization of GIPCs, a substantial increase in both sensitivity and fragmentation was observed on collision-induced dissociation of [M + Li](+) versus [M + Na](+) for the same components analyzed under similar conditions, similar to results obtained previously with cerebrosides. Molecular adduct fragmentation patterns were found to be systematic and characteristic for both the glycosylinositol and ceramide moieties with or without phosphate. Interestingly, significant differences were observed in fragmentation patterns when comparing GIPCs having Manalpha1 --> 2 versus Manalpha1 --> 6Ins core linkages. In addition, it was useful to perform tandem product ion scans on primary fragments generated in the orifice region, equivalent to ESI-(CID-MS)(2) mode. Finally, precursor ion scanning from appropriate glycosylinositol phosphate product ions yielded clean molecular ion profiles in the presence of obscuring impurity peaks. The methods were applied to detailed characterization of GIPC fractions of increasing structural complexity from a variety of fungi, including a non-pathogenic Basidiomycete (mushroom), Agaricus blazei, and pathogenic Euascomycete species such as Aspergillus fumigatus, Histoplasma capsulatum, and Sporothrix schenckii. The analysis confirmed a remarkable diversity of GIPC structures synthesized by the dimorphic S. schenckii, as well as differential expression of both glycosylinositol and ceramide structures in the mycelium and yeast forms of this mycopathogen. Mass spectrometry also established that the ceramides of some A. fumigatus GIPC fractions contain very little 2-hydroxylation of the long-chain fatty-N-acyl moiety, a feature that is not generally observed with fungal GIPCs.


Asunto(s)
Glicoesfingolípidos/análisis , Litio , Esfingosina/análogos & derivados , Agaricus , Aspergillus fumigatus , Ceramidas/análisis , Ceramidas/química , Glicoesfingolípidos/química , Histoplasma , Espectrometría de Masa por Ionización de Electrospray , Esfingosina/análisis , Esfingosina/química , Sporothrix
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