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Evolução hidroquímica em áreas adjacentes a locais de deposição de resíduos sólidos

Pereira, Vera Lúcia Vilela de Oliveira
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Dissertação de Mestrado
Publicado em 20/12/2005 POR
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Tese de mestrado; Indispensável à VIDA, a ÁGUA, recurso cada vez mais escasso e por isso tão valioso, será mais uma vez razão para a realização de uma tese. O objectivo primordial deste trabalho é averiguar o impacto ambiental dos depósitos de resíduos sólidos nas águas subterrâneas. Utilizou-se como suporte de trabalho um aterro sanitário em pleno funcionamento e duas lixeiras encerradas há sensivelmente quatro anos, aquando da realização do presente trabalho, todos localizados entre os concelhos de Braga e Póvoa de Lanhoso. Em termos geológicos o aterro sanitário assenta sobre granitóides tardi-F3 e tardi a pós-F3, respectivamente, Granito de Braga (Ymf π) e Granito de Briteiros (Yf). A Lixeira de Braga, por sua vez, encontra-se inserida numa ampla mancha metassedimentar constituída essencialmente por xistos argilosos, quartzofilitos, micaxistos e quartzitos. A Lixeira da Póvoa de Lanhoso, tal como o aterro sanitário, também se encontra instalada numa região de granitóides tardi-F3 – Granito de Agrela (Y πm). Nestas três áreas de estudo foi inventariado um total de 32 pontos de água (11 no Aterro Sanitário, 9 na Lixeira de Braga e 12 na Lixeira da Póvoa de Lanhoso) com vista a analisar a sua evolução hidroquímica. Para tal...

Depósitos costeiros quaternários do noroeste de Portugal (Minho - Neiva) : caracterização datação e interpretação paleoambiental; Quaternary coastal deposits of NW Portugal (Minho – Neiva area) : characterization, dating and paleoenvironmental interpretation

Carvalhido, Ricardo P.; Pereira, D. I.; Cunha, P.P.
Fonte: LNEG Publicador: LNEG
Tipo: Artigo de Revista Científica
Publicado em //2014 POR
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Este estudo apresenta a caracterização e datação absoluta de depósitos costeiros quaternários do NW Portugal, situados entre a foz dos rios Minho e Neiva, definindo-se a litostratigrafia e propondo-se uma correlação com os Estádios Isotópicos Marinhos MIS9-MIS1. Foram identificados paleoambientes continentais (pequenos leques aluviais e de cursos de água) e de transição (dunas eólicas, lagoas interdunares, estuário, praias de areia e de seixo) datados através de Luminescência Opticamente Estimulada (Método SAR - quartzo e feldspato) e AMS 14C. Estes depósitos constituem 16 unidades litostratigráficas conservadas nas plataformas costeiras modeladas a ca. 13 m (terraço T2), a ca. 8 m (terraço T3) e ca. 3 m (terraço T5) (n.m.m.), definindo 3 formações: a Formação de S. Sebastião (T2), provavelmente correlativa do MIS9; a Formação da Estrada Real (T3), provavelmente correlativa do MIS7 e a Formação de S. Domingos (T5), com 4 membros (Cão, S. Domingos, Montedor e Galeão) e compreendendo o intervalo temporal do MIS5 ao MIS1.; This study presents the characterization and absolute dating of Quaternary coastal deposits of NW Portugal, between the mouths of the rivers Minho and Neiva, defines their lithostratigraphy and ascribes them to the interval MIS9-MIS1. The deposits record continental (small alluvial fans and streams) and transition paleoenvironments (eolian dune...

Evolução cenozóica da área de Longroiva-Vilariça (NE Portugal)

Cunha, P. P.; Pereira, D. I.
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Artigo de Revista Científica
Publicado em 28/12/2010 POR
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In the Longroiva-Vilariça area, the identification of Cenozoic lithostratigraphic units, the sedimentology and the characterization of its geometric relations with tectonic structures allowed the interpretation of the palaeogeographic main stages: 1) the greenwhitish Vilariça Arkoses (Middle Eocene to Oligocene ?) represent proximal sediments of a very low gradient drainage towards the eastern Spanish Tertiary Duero Basin; 2)Quintãs Formation (late Miocene ?) are brown-reddish coloured piedmont alluvial deposits, correlative of important vertical displacement (western tectonic block relative uplift) along the NNE-SSW indent-linked strike-slip Bragança-Vilariça-Longroiva fault zone, interpreted as a reactivated deep hercynian fracture, with left-lateral movement; 3) the red Sampaio Formation (Gelasian-early Pleistocene ?)was interpreted as downhill conglomeratic deposits related with important overtrusting along this fault zone (the definition of the present-day narrow graben configuration) and correlative of the atlantic hydrographic incision stage beginning; 4) conglomeratic terraces (middle and late Pleistocene ?); 5) alluvial plains and colluvial deposits (Holocene).

Identification of Tsunami deposits and their impact on coastal zones : a study case of the Boca do Rio estuary (Algarve , Portugal)

Font, Eric; Veiga-Pires, C.; Pozo, Manuel; Nave, Silvia; Costas, Susana; Muñoz, Francisco Ruiz; Abad, Manuel
Fonte: PAGES Publicador: PAGES
Tipo: Artigo de Revista Científica
Publicado em /02/2013 ENG
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Tsunamis are unforeseeable phenomena and therefore one of the most devastating natural disasters in terms of human and economic losses. Their impact on coastal and nearshore zones is substantial and need to be accurately evaluated to improve their prevention and management. In the last decades, numerous investigations focused on the identification of paleotsunamis in order to evaluate their frequency in the geological record. However, because storm- and tsunami-deposits are generated by similar depositional mechanisms, their discrimination using classic sedimentological methods is an elusive prospect. A promising approach is to couple classic geological criteria with geophysical and geochemical proxies to search for new benchmarks of tsunami deposits and to integrate them into a multi-disciplinary study. To test our method, we investigate the 1755 Lisbon tsunami deposit from the Boca do Rio estuary and other Tsunami-induced deposits from Algarve (Portugal). First results show that, Sr and Ca are enriched in the tsunami layer probably linked to the presence of shelled organism. Contrarily, others marine seawater indicators, such as Ba and Br, which are usually more concentrated in brackish than in fresh water, and heavy minerals, which are generally used as high energy event indicators...

The quaternary geological history of the Santa Catarina Southeastern Region (Brazil)

CARUSO JR.,FRANCISCO; SUGUIO,KENITIRO; NAKAMURA,TOSHIO
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2000 EN
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This paper supply subsidies for Quaternary geological reconstruction of the southeastern State of Santa Catarina coast in Brazil, being based on detailed geological mapping supported by a series of drilling data, which allowed to establish a stratigraphical hierarchy of the sedimentary deposits. Among the mapped geological units stand out the extensive Pleistocene shallow marine sandy sediments, which are commonly referred as a barrier island - lagoonal depositional system. A drilling campaign done in the domain permitted the sampling of material for 14C datings, and the obtained data confirmed some previously assumed ages. The sequence of events, that originated the Holocene deposits, has been also reconstructed through drilling and 14C dating of the collected peat and shell samples. Finally, the main characteristics of the most promising mineral prospect of the area, represented by voluminous calcareous shell deposits associated with Holocene sediments, are also presented.

Araçatuba Formation: palustrine deposits from the initial sedimentation phase of the Bauru Basin

Fernandes,Luiz A.; Giannini,Paulo C. F.; Góes,Ana Maria
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 EN
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The Bauru Basin (Upper Cretaceous) accumulated an essentially sandy continental sedimentary sequence. In a first desertic phase the basaltic substratum was covered by a widespread and homogeneous aeolian sand unit with minor loess intercalations. The substratum relief favored the formation of an endorheic drainage system under semi-arid climate, a process that started the development of the Araçatuba Paleoswamp. The palustrine deposits (Araçatuba Formation) comprise siltstone and tipically greenish gray narrow tabular strata of sandstone cemented by carbonate. Moulds and gypsite and dolomite pseudomorphs were identified. The moulds seem to be genetically associated with desiccation cracks, root marks and climbing ripple lamination levels, that, on the whole, indicate calm shallow saline waters undergoing phases of subaerial exposition. At the boundaries of the study area, sand units may exhibit sigmoidal features and convolute bedding structure, which is characteristic of marginal deltaic deposits. The Araçatuba Formation is enclosed in and later overlaid by the aeolian deposits of the Vale do Rio do Peixe Formation.

Drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonephritis: a review

Amaro,Miguel Hage; Muccioli,Cristina; Motta,Mario Martins do Santos; Mitre,Jorge; Nassaralla,João Jorge; Silva,Luiz Augusto Siqueira; Aihara,Teruo
Fonte: Sociedade Brasileira de Oftalmologia Publicador: Sociedade Brasileira de Oftalmologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2015 EN
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The aim of this paper is to do a review of Drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonephritis. Drusenlike beneath retinal deposits in type II mesangiocapillary glomerulonephritis appear to develop at an early age, often second decade of life different of drusen from age-related macular degeneration (AMD).Long term follow-up of the cases in this disease shows in the most of them, no progression of the of drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonefritis, the most of subjects retain good visual acuity and no specific treatment is indicated.

A system to evaluate the performance of hydraulic nozzles used in stored grain preotection trials

Vásquez-Castro,Javier A.; Baptista,Gilberto C. de; Gadanha Jr.,Casimiro D.; Trevizan,Luiz R.P.
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2007 EN
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We developed a system to evaluate the performance of hydraulic nozzles used in stored corn and wheat grain protection experiments. An insecticidal mix was used as test fluid to determine the transversal volumetric distribution and droplets spectrum of a model TJ-60 8002EVS hydraulic nozzle. A mobile application system was built to apply a rate equivalent to 5 L t-1 and obtain theoretical concentrations of 10 and 0.5 mg kg-1 of fenitrothion and esfenvalerate, respectively. The corn and wheat grains were spread out as a fine layer. Three glass slides (0.1 × 0.05 m) were placed on the top surface of the grains to ensure that the intended application rate was achieved. After treatment, the deposits on both matrices were analyzed by gas chromatography. The fenitrothion deposit was higher than esfenvalerate, and the deposit on wheat was higher than on corn grains (P < 0.05). The deposits on the glass slides reached values of 100 and 93% of the intended theoretical fenitrothion and esfenvalerate concentrations, respectively. Deposits on the grains were lower than on the glass slides, with values of 64 and 52% of the intended theoretical fenitrothion and esfenvalerate concentrations, respectively. The results obtained demonstrate a high effectiveness of the method for evaluation of the performance of hydraulic nozzles when an insecticidal mix is used as test fluid. The factors that influenced insecticide deposition on glass slides and on grains are discussed in the present work.

Occurrence of mesangial IgA and IgM deposits in a control necropsy population.

Sinniah, R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1983 EN
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Kidney sections were obtained from 200 consecutive control necropsies of patients who died of traumatic injuries, with no clinical history of renal disease or other organic disease discovered at necropsy. Mesangial IgA as the predominant immunoglobulin was found in 8/200 (4%) cases, with accompanying IgM in two of them; and IgM alone in two (1%) subjects. Deposits of C3 alone in blood vessels was observed in nine (4.5%) cases. The glomerular morphology was essentially normal or minor change only, with one case showing diffuse mesangial hypercellularity. The high incidence of mesangial IgA deposits in the local apparently healthy population may reflect some common feature of the antigen(s) or complex involved. They may be of environmental, dietary or infectious origin. It is possible that many of these "spontaneous" deposits in the glomerular mesangium may result from the clearance of circulating non-nephritogenic immune complexes.

Amyloid deposits in the knee joint at autopsy.

Ladefoged, C
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1986 EN
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Joint capsule, meniscus, and cartilage from the patella and medial femoral condyle from 30 non-selected autopsies have been investigated for amyloid deposits with light and electron microscopy. Both right and left knee joints from 28 of the 30 autopsy specimens contained amyloid deposits (93%). The amyloid characteristically showed green dichroism in polarised light after staining with alkaline Congo red. The ultrastructural features were also characteristic of amyloid. Amyloid in capsule tissue was found in a subsynovial location, as well as deeper in the capsule tissue, while in the cartilage amyloid was localised along the surface. The meniscus tissue, in particular, contained heavy deposits of amyloid--mainly along the inner margin. Osteoarthritic changes, with fibrillation of the cartilage, were significantly related to amyloid deposition. No pathogenetic correlation between the osteoarthritic changes and amyloid deposition could be shown in the present investigation.

Macular pigment deposits in rhegmatogenous retinal detachment.

Theodossiadis, G P; Kokolakis, S N
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1979 EN
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This is a study of 20 cases of macular migration after operation for retinal detachment. The frequency of pigment deposits on the macula among the total number of operated detachments was 6.4%. The evolution of pigment migration depened on the form and type of the deposits. In some cases the pigment diminished or disappeared. In 6 of the 20 eyes with pigment migration puckering of the macula occurred 4 months or more after surgery. The improvement in visual acuity 6 months and more after operation was relatively less in the group with pigment deposits than in the group without pigment. In the former group static perimetry showed defects corresponding to the pigment migration.

Bacterial and fungal flora of dust deposits in a pig building.

Martin, W T; Zhang, Y; Willson, P; Archer, T P; Kinahan, C; Barber, E M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1996 EN
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OBJECTIVE--The purpose of the study was to investigate the bacterial and fungal flora of dust deposits in a newly built pig grower finisher building. Viable bacterial counts and microbial species found in a barn which had never housed pigs were compared with those in a barn housing 144 pigs. METHODS--The quantitative streak plate method was used to measure viable bacterial counts on nutrient agar or sheep blood agar. Viable bacterial counts of the dust deposits were expressed as the number of colony forming units (CFUs)/mg of dust. Gram positive cocci and Gram negative bacilli were identified by an automated system. Identifications with a confidence interval > 90% were accepted at the species level. Fungi were identified to the genus level with slide culture preparations on cereal agar. RESULTS--The lowest viable bacterial count (4.8 x 10(4)/mg of dust) was found in the barn with no pigs. In the barn with pigs the highest viable bacterial count (2.1 x 10(6)/mg of dust) was in dust from the top of a partition close to pig activity. Six species of bacteria or fungi were found in dust from the room with no pigs, whereas 22 different microorganisms were detected in dust from the room with pigs. With the exception of Enterobacter agglomerans no other species of the family Enterobacteriaceae was found in dust deposits in this new pig building. Twelve species of Gram positive bacteria were found in the room housing pigs. CONCLUSIONS--The pig is not only a source but also a disperser of airborne bacteria in pig buildings. Speciation of the microbial flora in dust from the pig building suggests that many of the microorganisms were either of human or environmental origin. Nevertheless as some of these microorganisms are known opportunistic pathogens or allergens and because of the documented increased incidence of chronic respiratory symptoms in pig workers...

IgA nephropathy: characterization of the polymeric nature of mesangial deposits by in vitro binding of free secretory component.

Bene, M C; Faure, G; Duheille, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1982 EN
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IgA nephropathy, as Berger defined it, is characterized by mesangial deposits of IgA, which are easily visualized by immunofluorescence on kidney biopsies. The structure (mono- or dimeric) of these IgA has not been clearly defined so far. Fifteen renal biopsies were studied to find out whether these IgA are serum monomers, or are polymers from a different origin. This was done by tissue fixation in vitro of free secretory component, which was then visualized by immunofluorescence (IF). In all 15 cases, the IgA deposits were shown to lack bound secretory component, but were able to bind, specifically, with the free secretory component. The presence of J chain in these deposits was also evidenced by indirect IF. These findings favour the hypothesis that these immunoglobulins are polymeric.

Deposits of immunoglobulins and C3 in the walls of human renal arteries.

Mekori, Y A; Steiner, P; Farkash, R; Moalem, T; Klajman, A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1981 EN
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Ninety-one renal biopsies were examined by immunofluorescent staining for the presence of C3 and immunoglobulins in the walls of renal arteries (RAW), tubules and glomeruli. The diseases studied were non-systemic renal immune complex diseases, systemic diseases with kidney involvement, renal diseases with minimal pathological changes and histological normal kidneys. In a high percentage of cases C3 and, to a lesser degree, deposits of immunoglobulins were found in the RAW, the deposits being found both in immunological and non-immunological diseases. Deposits of C3 but not of C4, C1q, fibrinogen, and immunoglobulins were found in the RAW of 11 normal kidneys examined.

Circulating serum amyloid P component is the precursor of amyloid P component in tissue amyloid deposits.

Baltz, M L; Caspi, D; Evans, D J; Rowe, I F; Hind, C R; Pepys, M B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1986 EN
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Intravenous administration of 125I-labelled isolated mouse serum amyloid P component (SAP) to mice with systemic amyloidosis was followed by specific deposition of the labelled protein in amyloidotic organs. Although only a small proportion of the total injected dose became localized in this way, the amount correlated with the quantity of amyloid present in different organs and was greatest in the spleen. No such localization was detected in the organs of control, untreated mice or animals which had received inflammatory stimuli but did not have amyloidosis. The labelled SAP was found by autoradiography to be present in the same distribution within the tissues as the Congophilic amyloid deposits. These observations establish directly, for the first time, that circulating SAP is the precursor of the amyloid P component (AP) in systemic amyloidosis. They were confirmed by the further finding that intravenous injection into amyloidotic mice of human SAP, either in whole human serum or in isolated pure form, was followed by appearance of the human SAP in the mouse amyloid deposits. In addition to elucidating one aspect of the pathogenesis of amyloid deposition and strengthening the homology of functional behaviour between SAP of different species...

Solubilization of intraglomerular deposits of IgG immune complexes by human sera or gamma-globulin in patients with lupus nephritis.

Tomino, Y; Sakai, H; Takaya, M; Miura, M; Suga, T; Endoh, M; Nomoto, Y
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1984 EN
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A study of the solubilization of glomerular deposition of IgG immune complexes by sera from patients with lupus nephritis is described. Renal biopsy specimens were obtained from 11 patients with lupus nephritis, five patients with IgA nephropathy and one patient with minimal change nephrotic syndrome. These renal specimens were incubated with fresh, stored or heated sera from the same patients or healthy adults and human gamma-globulins at 37 degrees C for 1 h in plastic test tubes. The sections were stained with FITC conjugated heavy chain specific anti-human IgG or C3 antisera and then examined with a fluorescent microscope. The sections were also stained with FITC conjugated human gamma-globulins and rhodamine conjugated anti-human IgG, IgM or IgA antisera and then examined by double exposure under a fluorescent microscope. It was demonstrated that fresh human sera or gamma-globulins significantly solubilize glomerular immune deposits in patients with lupus nephritis in vitro. It was indicated that the solubilization of IgG glomerular deposits from patients with lupus nephritis does not depend on complement. It is postulated that solubilization of immune deposits in glomeruli requires the excess amounts of antigenic substances in patients with lupus nephritis.

Isolated glomerulonephritis with mesangial IgA deposits.

Sissons, J G; Woodrow, D F; Curtis, J R; Evans, D J; Gower, P E; Sloper, J C; Peters, D K
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 13/09/1975 EN
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Mesangial deposits of IgA, occurring in the absence of systemic disease known to be associated with nephritis, were detected by immunofluorescence microscopy in renal biopsy specimens from 25 patients (4% of 630 specimens studied). Associated deposits of C3 were always present, usually with IgG, but IgM deposits were less common and C1q was never seen. On light microscopy most of the biopsy specimens showed mesangial of focal nuclear proliferation though some were normal. Fifteen of the 25 patients presented with macroscopic haematuria, which was usually recurrent and preceded by a sore throat, whereas the remaining, and usually older, patients presented with persistent proteinuria and were more likely to have impaired renal function. This incidence of "mesangial IgA disease" is less than that reported by French workers. There was a significantly high incidence of familial renal disease among these patients. No abnormalities of serum complement or IgA concentration were found.

Encrustation and Atherosclerosis: The Analogy Between Early in Vivo Lesions and Deposits Which Occur in Extracorporeal Circulations

Murphy, E. A.; Rowsell, H. C.; Downie, H. G.; Robinson, G. A.; Mustard, J. F.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 11/08/1962 EN
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A study was made of the relation between the pattern and topography of thrombus formation in models of various vessel configurations coupled into extracorporeal shunts in swine and the development of atherosclerosis at corresponding sites on swine aortas. The pattern and distribution of deposits formed in the models were strikingly similar to the pattern and distribution of incipient atherosclerosis at comparable sites in the vascular tree. The earliest and only consistent component of the flow chamber deposits was the blood platelet. The platelet deposits would frequently stain with oil red O. The cholesterol level of washed human platelets was found to show a good correlation with that in the plasma. This evidence suggests that deposition of particulate matter (chiefly platelets), largely determined by the hydraulic factors, may be an important factor in the early, as well as later, stages of atherosclerosis.

Glomerular immune deposits in experimental IgA nephropathy. A continuum of circulating and in situ formed immune complexes.

Chen, A.; Wong, S. S.; Rifai, A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1988 EN
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Studies were undertaken to elucidate the primary pathogenetic mechanisms responsible for immunoglobulin (Ig) A immune complexes formation and glomerular deposition in vivo. Monomeric (mIgA) and polymeric IgA (pIgA) anti-dinitrophenyl (DNP) were purified from MOPC 315 myeloma. A DNP-conjugated Ficoll was used as an antigen. For simulation of natural conditions of in vivo immune complex formation, 131I-DNP-Ficoll and 125I-IgA were administered through the intravenous and intraperitoneal routes, respectively. The kinetics half-life (t1/2) of the antigen (2.9 hours) and either the pIgA (7.2 hours) or mIgA (6.3 hours) in the experimental groups was not significantly different from the control. Glomerular IgA immune deposits were detectable only in mice that received pIgA and DNP-Ficoll. Plasma samples analyzed by gradient polyacrylamide gel electrophoresis revealed formation of large- and intermediate-sized pIgA complexes in circulation prior to glomerular deposition. Although mIgA failed to interact with such complexes in the circulation, it did bind to the pIgA immune deposits in the glomerulus. These results indicate that glomerular IgA immune deposits evolve from the localization of preformed circulating pIgA complexes that eventuates an in situ mIgA-mediated complex formation.

Calcium-acidic phospholipid-phosphate complexes in human hydroxyapatite-containing pathologic deposits.

Boskey, A. L.; Bullough, P. G.; Vigorita, V.; Di Carlo, E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1988 EN
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The deposition of calcium-containing crystals in tissues is due to a combination of factors: elevation in the concentrations of precipitating ions, formation of specific nucleators, and removal of macromolecules that inhibit crystal deposition. This study tested the hypothesis that calcium acidic phospholipid phosphate complexes, which promote hydroxyapatite deposition both in vitro and in vivo, are associated only with hydroxyapatite deposits, and furthermore, that the presence of these complexes is associated with all such hydroxyapatite deposits. Lipid analysis of 76 surgical specimens containing evidence of pathologic calcification (35 hydroxyapatite, 35 calcium pyrophosphate dihydrate, and 6 containing other crystalline materials) had mean complexed acidic phospholipid contents of 8.7, 1, and 0.012, (microgram/mg demineralized dry weight) respectively. Tissues that contained larger, more perfect hydroxyapatite crystals based on x-ray diffraction analyses, had a higher complexed acidic phospholipid content (7.5 +/- 4 micrograms/mg demineralized dry weight, N = 16) than tissues with poorly crystallized hydroxyapatite (3.9 +/- 2 micrograms/mg, N = 11). Histologically, tissues containing larger crystals were characterized by cell or tissue necrosis. Poorly crystalline deposits were found in tissues showing little or no evidence of cell necrosis or tissue degeneration.