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1.
Head Neck ; 17(5): 431-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8522446

RESUMO

BACKGROUND: Carcinoembryonic antigen (CEA) is an oncofetal glycoprotein involved in cell recognition and adhesion. Serum CEA has been extensively studied as a potential chemical marker for malignancy, most notably in patients with colon carcinoma. Serum CEA measurements have not been reported for patients with salivary gland carcinomas. METHODS: Serum CEA was measured in a case study using enzyme immunoassay with monoclonal antibody specific for CEA. Tissue was examined with standard histologic and immunohistologic methods. RESULTS: A patient was initially seen with adenoid cystic carcinoma (ACC) of the trachea and had a markedly elevated serum CEA level which declined after surgical resection. The serum CEA level became elevated again when the patient developed abdominal metastases and then declined after debulking of the tumor. Immunohistochemical study of the tumor was positive for CEA. CONCLUSIONS: The measurement of serum CEA levels may play a role in the management of patients with ACC. Clinical investigation utilizing monoclonal antibodies against CEA, for imaging and for the delivery of chemotherapy and radiotherapy may be worthwhile.


Assuntos
Antígeno Carcinoembrionário/sangue , Carcinoma Adenoide Cístico/sangue , Neoplasias Intestinais/secundário , Neoplasias Pulmonares/secundário , Neoplasias da Traqueia/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Adenoide Cístico/patologia , Carcinoma Adenoide Cístico/terapia , Terapia Combinada , Evolução Fatal , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Intestinais/sangue , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Neoplasias da Traqueia/patologia , Neoplasias da Traqueia/terapia
3.
Artigo em Inglês | MEDLINE | ID: mdl-7906981

RESUMO

This study compares the prevalence of elevated serological levels of erbB-2 and myc proteins in 36 breast cancer patients and 25 healthy, ambulatory female controls. The controls were frequency matched to the cases by age and ethnicity. Oncoprotein levels were determined blind to the "case-control status" of the individual from whom the specimen was derived. Corresponding tissue levels were examined in tumors of the 13 cases from whom sufficient tissue was available. Serum oncoproteins were elevated as follows: erbB-2 in one control (4%) compared with nine cases (25%; PFisher's exact = 0.03); myc in no control (0%) compared with seven cases (19%; PFisher's exact = 0.02). Elevated serum levels of erbB-2 or myc oncoproteins were detected in four of the seven cases (57.1%) of in situ cancer without evidence of infiltration. In all cases with elevated serum oncoproteins where tumor tissue was available, the corresponding protein was elevated in the tumor. The three cases who had elevated preoperative serum oncoprotein levels and from whom it was possible to procure postoperative specimens had normal postoperative serum oncoprotein levels. We conclude that (a) erbB-2 and myc oncoproteins are elevated in a proportion of breast cancer patients, (b) the tumor seems to be the source of the serum elevation, and (c) these proteins may be useful as part of a panel of biomarkers of early malignant disease.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Proteínas Oncogênicas Virais/análise , Proteínas Proto-Oncogênicas c-myc/análise , Adulto , Idoso , Neoplasias da Mama/sangue , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/química , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Metástase Linfática , Pessoa de Meia-Idade , Prevalência , Receptor ErbB-2
4.
Radiology ; 184(1): 55-8, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1319077

RESUMO

The accuracy of fine-needle aspiration (FNA) cytologic diagnosis of nonpalpable breast lesions and the prevalence of neoplasm occurring in areas unrelated to the radiologic abnormality were studied. Template-guided FNA cytologic examination was performed in 101 surgically excised breast specimens. The exact area of the mammographic abnormality was aspirated with radiographic control. Despite accurate placement of the needle for aspiration, seven of 101 aspirates (7%) yielded insufficient cytologic material. Ninety-four of the 101 aspirates (93%) were adequate for diagnosis. The cytologic diagnosis was benign in 58 (62%), atypical in seven (7%), suspicious for malignancy in four (4%), and malignant in 25 (27%). All cases diagnosed as suspicious or malignant and five of 58 cases diagnosed as benign at cytologic examination proved to be malignant at histologic examination. In three of these five the malignancy was in the area of the radiologic abnormality; in two it was not. FNA cytologic examination can be helpful in evaluating nonpalpable breast lesions, but it is not as accurate as histologic examination of surgically excised lesions.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Mama/patologia , Citodiagnóstico , Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Carcinoma/diagnóstico , Carcinoma/patologia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos , Mamografia
5.
Am J Pathol ; 122(1): 62-70, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2934987

RESUMO

Infection of normocholesterolemic, specific-pathogen-free chickens with Marek's disease herpesvirus (MDV) has been shown histologically to lead to chronic atherosclerosis like that in humans. The development of herpesvirus-induced atherosclerosis in vivo and the presence of specific Marek's antigen within aortic cells suggested that MDV infection may modify lipid metabolism and lead to significant lipid accumulation. Experiments reported herein were designed to determine the types and quantity of lipid present in aortas from MDV-infected and uninfected chickens between 2 and 8 months of age following infection and assess one possible mechanism of lipid accumulation by evaluating the effect of MDV infection on aortic cholesterol and cholesteryl ester (CE) metabolism. Chromatographic-fluorometric analyses indicated that at 4 and 8 months of age after MDV inoculation, MDV-infected animals had a significant (P less than 0.05) two-fold to threefold increase in total aortic lipid accumulation characterized by significant increases in cholesterol, CE, triacylglycerol, and phospholipid as compared with aortas from uninfected animals. At 8 months of age, similar increases in aortic lipid accumulation were observed in MDV-infected animals as compared with those animals vaccinated with turkey herpesvirus and later challenged with MDV. CE synthetic activity was increased significantly by 50% at 4 months of age in the MDV-infected group as compared with the uninfected group, which could explain the initial increase in CE accumulation. By 8 months of age, the authors also observed a twofold increase in CE synthetic activity and a 30% and 80% reduction in lysosomal and cytoplasmic CE hydrolytic activities, respectively, in aortas of MDV-infected chickens as compared to controls. Moreover, infection with MDV blocked the activation of cytoplasmic CE hydrolytic activity by dibutyryl cyclic AMP or exogenous cyclic AMP-dependent protein kinase. Taken together, these results suggest that lipid accretion in aortas of MDV-infected chickens results, in part, from alterations in cholesterol/CE metabolism during early stages of the disease. These findings support the hypothesis that human atherosclerosis may result from specific herpesvirus infection which can alter lipid metabolism and lead to lipid accretion.


Assuntos
Aorta/metabolismo , Arteriosclerose/etiologia , Colesterol/metabolismo , Doença de Marek/metabolismo , Animais , Aorta/enzimologia , Galinhas , Colesterol/sangue , Ésteres do Colesterol/metabolismo , Ativação Enzimática , Herpesviridae/imunologia , Doença de Marek/complicações , Doença de Marek/enzimologia , Fosfolipídeos/metabolismo , Organismos Livres de Patógenos Específicos , Esterol Esterase/metabolismo , Esterol O-Aciltransferase/metabolismo , Triglicerídeos/metabolismo , Vacinas Virais
6.
Am J Pathol ; 120(1): 6-11, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4014443

RESUMO

The interaction of arterial proteoglycans (PGs) and low-density lipoproteins (LDLs) has been postulated to be an important factor in extracellular cholesterol accumulation in the arterial wall. In the present study, insoluble complexes of LDL and PG (LDL-PG) were prepared and their effects on cholesteryl ester accumulation in mouse peritoneal macrophages was tested. The cholesteryl ester content of macrophages incubated with LDL-PG for 3 days was greater than 20 times that observed in cells incubated with LDL alone. The uptake of 125I-LDL by macrophages was markedly stimulated if LDL was incorporated into a complex with PG. However, in contrast to either LDL or acetylated LDL (ALDL), the extent of subsequent degradation of LDL-PG by the cells was reduced. The uptake and degradation of LDL-PG complexes stimulated macrophage incorporation of 14C-oleic acid into cholesteryl oleate 4- to 5-fold over LDL alone; however, esterification was significantly less than that observed with ALDL, even though more LDL-PG was degraded. Ultrastructurally, macrophages incubated with LDL-PG complexes contained lipid droplets as well as numerous phagocytic vacuoles often containing material similar in appearance to insoluble complexes. These results demonstrate that components of the extracellular matrix, such as PG, can modify the catabolism of LDL by scavenger cells. This phenomenon may be potentially important with respect to foam-cell genesis from macrophages in the arterial wall.


Assuntos
Ésteres do Colesterol/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Proteoglicanas/metabolismo , Animais , Bovinos , Ésteres do Colesterol/biossíntese , Endocitose , Feminino , Humanos , Técnicas In Vitro , Macrófagos/ultraestrutura , Camundongos , Ácido Oleico , Ácidos Oleicos/metabolismo , Solubilidade
7.
Exp Mol Pathol ; 42(3): 306-19, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3996553

RESUMO

Glycosaminoglycans (GAG) are believed to be important in the pathogenesis of atherosclerosis. We have previously demonstrated that areas of injured aorta that have been re-endothelialized accumulate increased amounts of lipid and GAG when compared to areas remaining de-endothelialized. We have now examined the net incorporation of labeled precursors into the individual GAG present in both re-endothelialized and de-endothelialized areas of rabbit aorta. Aortic tissue was examined at 2-3 and 10-14 weeks after a denuding injury by incubating tissue minces with [3H]glucosamine and sodium [35S]sulfate for 24 hr. Following incubation, the aortic GAG were isolated and assayed for uronic acid concentration and radioactivity. Results indicate that the total GAG concentration was significantly greater (P less than 0.001) in the re-endothelialized (9.46 +/- 0.29 micrograms/mg lipid-free dry residues (LFDR), mean +/- SE) as compared to de-endothelialized (7.89 +/- 0.43 micrograms/mg LFDR) areas. The concentration in uninjured aorta was 9.01 +/- 0.69. The difference between the injured tissues was attributable to increased concentrations of sulfated GAG. Hyaluronic acid and chondroitin sulfate were the most metabolically active of the GAG in either uninjured or injured aorta, together accounting for over 75% of the 3H label. The 3H specific radioactivities of the four GAG in the short-term, re-endothelialized subgroup were all increased nearly twice that found in uninjured and de-endothelialized tissues. With the exception of heparan sulfate, no significant differences were noted in the 3H specific radioactivities between the re-endothelialized and de-endothelialized areas in the long-term subgroup. These results indicate that, relative to adjacent areas of de-endothelialization, GAG preferentially accumulate in re-endothelialized areas even as early as 2-3 weeks following a denuding injury. Overall, metabolic data suggest that increased synthesis is responsible for this effect, although the net contribution of degradative processes cannot be overlooked since GAG turnover was not specifically examined. Thus, it is possible that regenerated endothelium may modify the GAG metabolism of the arterial wall following arterial injury.


Assuntos
Aorta/metabolismo , Glicosaminoglicanos/metabolismo , Animais , Aorta/lesões , Dermatan Sulfato/metabolismo , Endotélio/metabolismo , Endotélio/patologia , Endotélio/fisiologia , Feminino , Heparitina Sulfato/metabolismo , Coelhos , Regeneração , Radioisótopos de Enxofre/metabolismo , Fatores de Tempo , Trítio/metabolismo
8.
J Cell Biol ; 99(4 Pt 1): 1266-74, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6480690

RESUMO

The sequestration of low-density lipoprotein (LDL) by components of the vascular extracellular matrix has long been recognized as a contributing factor to lipid accumulation during atherogenesis. The effects, however, that components of the extracellular matrix might have on LDL catabolism by scavenger cells have been little investigated. For these purposes we have prepared insoluble complexes of LDL, heparin, fibronectin, and denatured collagen (gelatin) and examined their effects on lipid accumulation, LDL uptake and degradation, and cholesteryl ester synthesis in mouse peritoneal macrophages. The results of these experiments have demonstrated that the cholesteryl ester content of macrophages incubated with a particular suspension of LDL, heparin, fibronectin, and collagen complexes is four- to fivefold that of cells incubated with LDL alone. The uptake of complexes containing 125I-LDL is rapid; however, in contrast to either endocytosed 125I-LDL or 125I-acetyl LDL, the degradation of complex-derived LDL is impaired. In addition, the uptake of complex-derived LDL stimulates the incorporation of [14C]oleic acid into cholesteryl oleate, however, the stimulation was a small fraction of that observed in cells incubated with acetyl LDL. Ultrastructurally, macrophages incubated with LDL, heparin, fibronectin, and collagen complexes did not contain many lipid droplets, but rather their cytoplasm is filled with phagosomes containing material similar in appearance to LDL-matrix complexes. These results indicate that components of the extracellular matrix can alter the catabolism of LDL by scavenger cells, suggesting that they may play a role in cellular lipid accumulation in the atherosclerotic lesion.


Assuntos
Ésteres do Colesterol/metabolismo , Colágeno/farmacologia , Fibronectinas/farmacologia , Heparina/farmacologia , Lipoproteínas LDL/farmacologia , Macrófagos/metabolismo , Animais , Células Cultivadas , Humanos , Cinética , Lipoproteínas LDL/metabolismo , Substâncias Macromoleculares , Macrófagos/efeitos dos fármacos , Macrófagos/ultraestrutura , Camundongos , Microscopia Eletrônica , Desnaturação Proteica
9.
Am J Pathol ; 114(1): 112-20, 1984 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6691410

RESUMO

Although arterial injury is believed to be an important factor in the pathogenesis of atherosclerosis, little is known about lipoprotein accumulation in the injured arterial wall. In experiments reported here, the authors quantitated the accumulation of iodinated lipoprotein and albumin in reendothelialized and deendothelialized rabbit aorta. Results indicate that over the experimental period, insudated lipoprotein but not albumin is retained in the reendothelialized aorta. Neither lipoprotein nor albumin was retained in the adjacent persistently deendothelialized aorta. Findings are consistent with the hypothesis that sequestration of lipoprotein in reendothelialized artery is one mechanism by which lipid accumulates in these areas.


Assuntos
Aorta/lesões , Lipoproteínas LDL/metabolismo , Regeneração , Albumina Sérica/metabolismo , Animais , Aorta/fisiologia , Transporte Biológico , Endotélio/metabolismo , Endotélio/fisiologia , Feminino , Radioisótopos do Iodo , Lipoproteínas LDL/sangue , Lipoproteínas LDL/isolamento & purificação , Coelhos , Soroalbumina Radioiodada/análise
10.
Am J Pathol ; 113(2): 156-64, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6638149

RESUMO

Previous studies have indicated that reendothelialized regions of injured rabbit aortas are more susceptible to diet-induced atherosclerosis than persistently deendothelialized regions or uninjured aortas. However, the mechanism responsible for this selective lipid deposition is not understood. One possibility is that these regions differ with respect to the quantity and type of glycosaminoglycan-containing proteoglycans which are known to interact with lipoproteins. To determine whether these regions differed with respect to their glycosaminoglycan composition, the authors divided 53 rabbits into four groups. Groups IA and IB were fed a regular diet beginning 5 weeks prior to aortic deendothelialization; Groups IIA and IIB were fed the same diet supplemented with 0.5% cholesterol. The rabbits were continued on these diets following aortic deendothelialization with a balloon catheter. Those in Groups IA and IIA were sacrificed either at 2-5 weeks or 6-8 weeks following deendothelialization; proteoglycans were assessed morphometrically following staining with alcian blue. Groups IB and IIB were sacrificed at 10 weeks following injury; glycosaminoglycans were extracted from deendothelialized and reendothelialized aortas, separated by electrophoresis, and quantitated by scanning densitometry. Morphometric analysis of stained aortic sections revealed significantly increased quantities of alcianophilic material in the neointima of reendothelialized aortas as compared with deendothelialized aortas in both diet groups. Chemical analysis revealed significantly more of each glycosaminoglycan in reendothelialized aortas when compared with deendothelialized or uninjured aortas. The major glycosaminoglycans present in all regions were heparan sulfate and chondroitin sulfate; and although absolute quantities of these particular glycosaminoglycans increased in the reendothelialized region, their relative percentages remained the same for each area analyzed. Cholesterol feeding did not appear to influence glycosaminoglycan concentration and composition in reendothelialized and deendothelialized regions when compared with normal diets, but cholesterol feeding alone did increase aortic glycosaminoglycans in uninjured aortas. The results suggest that the presence of endothelium influences the quantity and type of glycosaminoglycans accumulating in the neointima, and that the differences in proteoglycans in the reendothelialized artery may account at least in part for the propensity of this area to accumulate lipid and evolve as atherosclerosis.


Assuntos
Aorta/lesões , Glicosaminoglicanos/metabolismo , Animais , Aorta/análise , Aorta/metabolismo , Colesterol/sangue , Endotélio/metabolismo , Endotélio/patologia , Glicosaminoglicanos/análise , Coelhos
11.
Fed Proc ; 42(8): 2476-9, 1983 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-6840298

RESUMO

Repeated experiments have established that infection with Marek's disease herpesvirus (MDV) leads to atherosclerosis in specific pathogen free (SPF) normocholesterolemic chickens. Neither normocholesterolemic nor hypercholesterolemic uninfected SPF chickens develop this disease. The MDV-induced arterial disease is remarkably similar to chronic human atherosclerosis. Cholesterol and saturated cholesteryl esters accumulated in cultured arterial smooth muscle cells (SMC) infected with MDV. Similar preliminary observations were made in vivo. These findings suggest that MDV-induced alteration of SMC lipid metabolism is of major importance in the pathogenesis of MDV-induced atherosclerosis. In addition, immunization with turkey herpesvirus, used commercially to prevent MDV-induced tumors in chickens, also protected against MDV-induced atherosclerosis. This animal model has introduced important new dimensions and tools in atherosclerosis research: a defined etiologic agent (MDV) that causes atherosclerosis in a defined animal of known genetic susceptibility to the etiologic agent. With these tools, important mechanisms in the pathogenesis of atherosclerosis may be established in a relatively short period of time. Further, this animal model should be considered important in other models of atherosclerosis research because herpesvirus infections are ubiquitous in these animals. Finally, because humans are widely and persistently infected with up to five herpesviruses, these studies may lead to the understanding and eventual control of human atherosclerosis.


Assuntos
Arteriosclerose/etiologia , Galinhas , Doença de Marek/complicações , Animais , Artérias/análise , Colesterol/análise , Herpesviridae/imunologia , Imunização , Lipídeos/análise , Doenças das Aves Domésticas/complicações
13.
J Biol Chem ; 258(1): 192-8, 1983 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-6848493

RESUMO

We describe here an activable neutral cholesteryl esterase (EC 3.1.1.13) in arteries similar to the hormone-sensitive lipase of adipose tissue and adrenal cortex. Maximum enzyme activity in rabbit aorta was given by cholesteryl ester substrates dispersed as a mixed micelle with phosphatidylcholine and Na taurocholate (molar ratio 1:4:2). A quantitative assay of enzymic activity was obtained with the following component concentrations: 6.0 microM cholesteryl [1-14C]oleate, 23.7 microM phosphatidylcholine, 12.5 microM Na taurocholate, 0.04% serum albumin, and 85 mM K phosphate buffer, pH 7.0. The enzymic activity in aortic homogenates was stimulated 2-fold by addition of 5 microM glucagon or 100 microM dibutyryl cAMP. This activation was Mg-ATP dependent. Addition of 50 micrograms/ml of exogenous protein kinase could reverse the action of protein kinase inhibitor on dibutyryl cAMP activation of the neutral cholesteryl esterase. In addition to activation by cAMP-dependent protein kinase, the enzyme could be distinguished from the more active arterial lysosomal cholesteryl esterase by its pH 7.0 optimum, relative stability to preincubation at elevated temperatures, and exclusive localization in the cell cytosol. Subcellular fractionation of lipid-laden arterial foam cells revealed a significant portion of the neutral cholesteryl esterase bound to cytoplasmic cholesteryl ester-rich lipid droplets. Our results suggest that the breakdown of cytoplasmic cholesteryl ester droplets in arterial cells may be under hormonal regulation.


Assuntos
Aorta Torácica/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Lisossomos/enzimologia , Esterol Esterase/metabolismo , Animais , Ácidos e Sais Biliares/farmacologia , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Micelas , Fosfolipídeos/farmacologia , Coelhos
14.
J Clin Invest ; 70(3): 479-88, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6286723

RESUMO

We tested the hypothesis that prostacyclin (PGI2), 6-keto-prostaglandinF1 alpha(6-keto-PGF1 alpha), and several E series prostaglandins (PG) may affect the activity of cholesteryl ester (CE) hydrolase since our previous experiments indicated that smooth muscle cells (SMC) in neointima of injured rabbit aorta (a) acquire the capacity to produce PGI2 and (b) have increased lysosomal CE hydrolytic (acid cholesteryl ester hydrolase [ACEH])activity. Using cultured SMC from rabbit thoracic aorta, we demonstrated that PGI2, 6-keto-PGF1 alpha, and 6-keto-PGE1 enhanced ACEH activity fourfold. No significant effects on ACEH activity were observed with PGE1 or PGE2. Preincubation of SMC with an inhibitor of adenylate cyclase activity (dideoxyadenosine) abolished the effect of these PG on CE hydrolytic activity. Addition of dibutyryl cAMP to these SMC significantly increased ACEH activity. Although concentrations of PGI2 used significantly increased cAMP levels, proliferation of these SMC was not observed. In related experiments, we determined if the addition of PGI2, 6-keto-PGF1 alpha, or 6-keto-PGE1 to cultured aortic SMC would enhance the egress of unesterified cholesterol and CE from these SMC. A significant loss of total cholesterol from PG-treated SMC was observed at the end of 14 d. Results suggest that increased synthesis of PGI2 by neointimal SMC in the injured aortic wall may, at least in part, explain the changes in CE catabolism and accumulation following injury. These PG may also be important in CE metabolism and accumulation in human arteries.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Epoprostenol/farmacologia , Músculo Liso Vascular/enzimologia , Prostaglandinas/farmacologia , Esterol Esterase/metabolismo , Animais , Ácidos Araquidônicos/farmacologia , Bucladesina/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Ésteres do Colesterol/metabolismo , AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Lisossomos/enzimologia , Coelhos
15.
Exp Hematol ; 10(6): 524-32, 1982 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6180922

RESUMO

Mast cells were obtained from mouse bone marrow cells cultured for 14 days in medium derived from Concanavalin A (Con A) stimulated mouse spleen cells. Upon passive sensitization of the cultured cells with immunoglobulin E (IgE), histamine release from mast cells was approximately 200% above control within 1 min of incubation with anti-IgE. The calcium inonophore A 23187 also evoked a concentration-dependent (10(-8) M to 6 x 10(-7) M) histamine release following a 6 min incubation. Transmission electron microscopy (TEM) demonstrated that the secretory granules of the cultured cells have a peripheral crystalline pattern, like that previously demonstrated for mast cells. Scanning electron microscopy (SEM) illustrated spherical cells with surfaces traversed by many ridge-like folds. Intragranular fusion, following exposure of the IgE-bearing cells to anti-IgE, led to accumulation of the granules into channels which, on study with both transmission and scanning electron microscopy, appeared to be associated with the cell surface.


Assuntos
Células da Medula Óssea , Liberação de Histamina , Mastócitos/fisiologia , Animais , Calcimicina/farmacologia , Células Cultivadas , Concanavalina A/farmacologia , Meios de Cultura , Grânulos Citoplasmáticos/ultraestrutura , Exocitose , Liberação de Histamina/efeitos dos fármacos , Imunoglobulina E/imunologia , Técnicas In Vitro , Masculino , Mastócitos/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura
17.
Am J Pathol ; 107(2): 186-90, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7044131

RESUMO

The effect of diet-induced hypercholesterolemia on the recovery of prostacyclin (PGI2) synthetic capacity was assessed at the luminal surface of previously injured rabbit aorta. Prostacyclin synthesis and release were measured by radioimmunoassay following arachidonic acid stimulation of deendothelialized and reendothelialized aortas of hypercholesterolemic rabbits. Assay of PGI2 production by aorta was performed at 15, 35, and 70 days following removal of endothelium with a balloon catheter. Prostacyclin production by both deendothelialized and reendothelialized areas of aorta from normocholesterolemic rabbits was initially low following injury and increased with time, reaching levels at 70 days equal to uninjured aortas. Prostacyclin production by both deendothelialized and reendothelialized areas of aorta from rabbits with moderately elevated serum cholesterol concentrations (203 to 350 mg/dl) was also initially low, but in contrast to normocholesterolemic rabbits, it did not increase with time. Results indicate that hypercholesterolemia like that seen in humans inhibits the recovery of PGI2 production in deendothelialized and reendothelialized areas of previously injured rabbit aorta.


Assuntos
Aorta/lesões , Colesterol na Dieta/efeitos adversos , Epoprostenol/biossíntese , Hipercolesterolemia/metabolismo , Prostaglandinas/biossíntese , Animais , Aorta/metabolismo , Colesterol/sangue , Endotélio/metabolismo , Feminino , Hipercolesterolemia/etiologia , Coelhos , Fatores de Tempo
18.
Am J Pathol ; 105(2): 176-84, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6271018

RESUMO

In our previous experiments, atherosclerosis similar to that in humans was reproducibly induced in both normocholesterolemic and hypercholesterolemic specific-pathogen-free (SPF) chickens by infection with Marek's disease herpesvirus (MDV). In contrast, uninfected chickens fed either relatively cholesterol-poor or cholesterol-supplemented diets did not develop this arterial disease. In experiments reported here, the hypothesis that infection of arterial smooth muscle cells (SMCs) with MDV would enhance lipid accumulation in these cells was tested. The number of MDV-infected SMCs with lipid stained with oil red O was assessed, and the lipid content of these cells was quantitated chemically by chromatographic and fluorometric analyses. These data were compared to those of uninfected control cells and, in the case of chemical analyses, were also compared to SMCs infected with a second avian herpesvirus, turkey herpesvirus (HVT). Results indicate the following: 1) The percentage of MDV-infected SMCs containing stainable lipid was significantly greater than the percentage of uninfected SMCs; 2) Increased total lipid accumulation was observed in MDV-infected SMC, particularly cholesterol (CH) and cholesteryl esters (CEs), as compared with uninfected or HVT-infected cells; 3) The types of CEs and nonesterified fatty acids (NEFA) accumulating in MDV-infected cells (particularly saturated types of CEs and NEFAs) were significantly different than those in uninfected or HVT-infected SMCs. These qualitative and quantitative differences in lipid content between infected and uninfected SMCs suggest that infection with MDV results in altered intracellular lipid metabolism. Results support the hypothesis that lipid accumulation in arteries of normocholesterolemic chickens may result from MDV infection acting at the cellular level to induce lipid accumulation that resembles that in human atheroarteriosclerosis.


Assuntos
Colesterol/metabolismo , Infecções por Herpesviridae/metabolismo , Doença de Marek/metabolismo , Músculo Liso Vascular/metabolismo , Animais , Arteriosclerose/etiologia , Células Cultivadas , Galinhas , Colesterol/análise , Ésteres do Colesterol/análise , Ésteres do Colesterol/metabolismo , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/metabolismo , Lipídeos/análise , Músculo Liso Vascular/análise , Perus
19.
J Clin Invest ; 67(3): 735-41, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7009648

RESUMO

Prostacyclin (PGI2) synthetic capacity was assayed at the surface of aortas at various intervals after removal of endothelium with a balloon catheter. Results were correlated with morphologic changes in the vessel wall seen by light microscopy, scanning and transmission electron microscopy. To assay PGI2 synthetic capacity, we applied an incubation chamber to the luminal surface of the aortas; after arachidonic acid stimulation we assayed the PGI2 synthesized with a bioassay and radioimmunoassay. PGI2 synthesis in de-endothelialized aortas was determined immediately after balloon-catheter injury and at intervals of 1 h and 2, 4, 15, 35, and 70 d. PGI2 synthesis was low at 1 h and increased over time with levels at 35 and 70 d reaching that of normal artery. Scanning and transmission electron microscopy of de-endothelialized areas showed persistent absence of endothelium with formation of a neointima composed of smooth muscle cells. De-endothelialized aorta was covered with adherent platelets shortly after injury, however several days later only a few platelets adhered to the denuded surface. Results indicated that (a) endothelium is responsible for nearly all PGI2 production at the luminal surface of the normal aorta, (b) de-endothelialized muscular neointima synthesized increasing quantities of PGI2 with time after injury, and (c) increase of PGI2 production at the luminal surface of de-endothelialized aorta correlates with formation of a neointima and with the acquired thromboresistance of the aorta.


Assuntos
Aorta/metabolismo , Epoprostenol/biossíntese , Músculo Liso Vascular/metabolismo , Prostaglandinas/biossíntese , Trombose , Animais , Diferenciação Celular , Endotélio/metabolismo , Microscopia Eletrônica , Coelhos , Fatores de Tempo
20.
Am J Pathol ; 102(1): 28-39, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7468757

RESUMO

Results of previous experiments in this laboratory indicate that lipids, especially cholesterol and cholesteryl ester, preferentially accumulate in re-endothelialized, as compared with de-endothelialized, areas of aorta (Am J Pathol 1980, 99:81-104). In the experiments reported here, the hypothesis that this lipid accumulation results from alterations in arterial wall metabolism induced by injury and modified by endothelium was tested. Activities of the two cholesterol-ester-metabolizing enzymes acyl CoA: cholesterol acyltransferase and acid cholesteryl esterase were assayed in uninjured aortas and in de-endothelialized and re-endothelialized areas of balloon-catheter-injured aortas from normocholesterolemic and hypercholesterolemic rabbits. Activities of marker enzymes for major cell organelles were also assayed. Our results indicate that acyl CoA: cholesterol acyltransferase activity was similarly increased in re-endothelialized and de-endothelialized areas of injured aortas. Activity of acid cholesteryl esterase was also increased; however, it was significantly less in re-endothelialized as compared with de-endothelialized areas. Activities of several marker enzymes were changed in injured aortas, particularly in de-endothelialized as compared with re-endothelialized areas. These findings suggest that 1) injury predisposes to general metabolic changes in the aorta that are modified by endothelium and 2) increased cholesteryl ester accumulation in re-endothelialized aortas occurs at least in part from increased synthesis and decreased hydrolysis.


Assuntos
Aorta/lesões , Animais , Aorta/citologia , Aorta/metabolismo , Colesterol/sangue , Colesterol na Dieta/metabolismo , Endotélio/fisiologia , Feminino , Coelhos , Regeneração , Esterol Esterase/metabolismo , Esterol O-Aciltransferase/metabolismo
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