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2.
J Biol Regul Homeost Agents ; 30(3): 859-861, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27655511

RESUMEN

The increase in oral rehabilitation by means of dental implants has required an evolution of the related managing protocols and correct updating of the skills of dental professionals. Postsurgical management of the clinical case is aimed to stabilize the obtained results and preserve them from adverse conditions: a healthy implant prosthesis is maintained thanks to the huge number of consolidated protocols of oral hygiene. This practice plays a decisive role in the prevention of perimplant pathologies, forming a strong basis to ensure long implant life and avoid unnecessary and painful new surgical procedures. Furthermore, dental companies, in order to satisfy the new needs of professionals in oral hygiene, have produced new instrumentations and targeted drugs, in agreement to the cutting-edge scientific literature, thus creating a new market attracting huge interests in healthcare. The purpose of this topical review is to briefly comment on the state of the art of post-surgical dental implant management. This research is aimed to report the current protocols available to reduce the risk of oral diseases and prevent the progression of perimplant complications. Special focus has been dedicated to the most effective surgical and non-surgical protocols for treating mucositis and perimplantitis.


Asunto(s)
Implantación Dental , Implantes Dentales , Periimplantitis/etiología , Complicaciones Posoperatorias/etiología , Estomatitis/etiología , Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/prevención & control , Antibacterianos/uso terapéutico , Clorhexidina/análogos & derivados , Clorhexidina/uso terapéutico , Implantación Dental/efectos adversos , Implantes Dentales/efectos adversos , Humanos , Boca/microbiología , Antisépticos Bucales/uso terapéutico , Higiene Bucal/métodos , Oseointegración , Periimplantitis/sangre , Periimplantitis/prevención & control , Periimplantitis/terapia , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/terapia , Estomatitis/sangre , Estomatitis/prevención & control , Estomatitis/terapia
3.
J Environ Manage ; 155: 136-44, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25863437

RESUMEN

Within the framework of the European Life+-funded project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), which was aimed at demonstrating the effectiveness of photocatalytic coating materials on a realistic scale, a photocatalytic de-polluting field site was set up in the Leopold II tunnel in Brussels, Belgium. For that purpose, photocatalytic cementitious materials were applied on the side walls and ceiling of selected test sections inside a one-way tunnel tube. This article presents the configuration of the test sections used and the preparation and implementation of the measuring campaigns inside the Leopold II tunnel. While emphasizing on how to implement measuring campaigns under such conditions, difficulties encountered during these extensive field campaigns are presented and discussed. This included the severe de-activation observed for the investigated material under the polluted tunnel conditions, which was revealed by additional laboratory experiments on photocatalytic samples that were exposed to tunnel air. Finally, recommendations for future applications of photocatalytic building materials inside tunnels are given.


Asunto(s)
Contaminantes Atmosféricos/química , Contaminación del Aire/prevención & control , Catálisis , Emisiones de Vehículos , Bélgica , Materiales de Construcción , Humanos
4.
Eur Rev Med Pharmacol Sci ; 13(2): 71-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19499840

RESUMEN

Secondary or pathologic fractures, associated with osteosarcoma, have been considered for a long time to be a negative prognosis regarding its evolution in the patients. The aim of this study was to evaluate the prognostic importance of such pathologic fractures in osteosarcoma patients receiving new therapies as well as the best conditions for surgery aiming at "limbs salvage". On a total of 22 patients affected by osteosarcoma, we performed a retrospective study with 12 patients showing pathologic fractures caused by osteosarcoma and 10 patients without any pathologic fracture. The patients enrolled into Timisoara University Hospital have been followed up along 5 years or until a reappearance of either the disease or metastases, distant or local.


Asunto(s)
Neoplasias Óseas/complicaciones , Fracturas Óseas/etiología , Recuperación del Miembro/métodos , Osteosarcoma/complicaciones , Anciano , Antineoplásicos/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Femenino , Estudios de Seguimiento , Fracturas Óseas/cirugía , Hospitales Universitarios , Humanos , Masculino , Recurrencia Local de Neoplasia , Osteosarcoma/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos
5.
Eur Rev Med Pharmacol Sci ; 12(5): 285-92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19024211

RESUMEN

The effects on sexual behaviour of acute low doses of methylendioxymethamphetamine (MDMA) (0.3, 1, 3 mg/kg/i.p.), alone or in combination with exposure to loud music (1 h stimulation), were investigated in Wistar rats. Results indicate that acute MDMA, at dose of 3 mg/kg, notably impaired copulatory behavior of sexually experienced male rats. In particular, MDMA-exposed animals exhibited a significant increase in intromission and ejaculation latencies as well as a significant decrease in percentage of rats displaying copulatory activity (one intromission at least). Surprisingly, one hour exposure to loud music, which per se resulted ineffective, antagonized the suppressive effect of MDMA by increasing the percent of animals displaying sexual activity. However, combined treatment of MDMA and music stimulation did not fully restore normal sexual behavior as the animals reaching ejaculation still showed a marked reduction of copulatory efficiency. These findings demonstrate that the systemic administration of a single low dose of MDMA, alone or in combination with loud music, which is commonly present in certain environments such as rave parties, notably impairs copulatory activity of male rats.


Asunto(s)
Alucinógenos/farmacología , Música/psicología , N-Metil-3,4-metilenodioxianfetamina/farmacología , Conducta Sexual Animal/efectos de los fármacos , Animales , Copulación/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratas , Vocalización Animal/efectos de los fármacos
6.
Clin Ter ; 159(4): 239-42, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18776980

RESUMEN

OBJECTIVE: A number of recent studies have expanded our understanding of Helicobacter pylori (Hp) infection and of the pathogenesis of MALT lymphoma. The purpose of this paper is to perform a retrospective analysis of the clinical characteristics of gastric MALT lymphoma and its relationship with H. pylori infection in authors' experience. MATERIALS AND METHODS: We report nineteen patients observed during 10 years, presenting with gastric MALTomas at any stage. The staging classification and the presence of H. pylori infection have been assessed, and the chosen therapy also. RESULTS: The most part of our patients underwent surgery, still now resulting the most effective therapy. None of the patients had eradicating therapy due to their poor compliance and because the most part of cases were observed before the time of clinical validation of such treatment. CONCLUSIONS: In our series, surgery was effective for treatment of gastric MALT lymphomas. Surgery and chemotherapy remain, in accord with literature data, the best treatment for gastric MALTomas. Hence, because Hp may play a role in the development of such pathology in certain patients, antibiotic treatment for Hp eradication should not be discouraged in these patients, especially in them with low grade gastric MALT lymphomas. In fact, the failure of this therapy will not modify either survival or later recourse to surgical and/or radio- and chemotherapy.


Asunto(s)
Gastrectomía/estadística & datos numéricos , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/aislamiento & purificación , Linfoma de Células B de la Zona Marginal/microbiología , Neoplasias Gástricas/microbiología , Adulto , Anciano , Antibacterianos/uso terapéutico , Antineoplásicos/uso terapéutico , Terapia Combinada , Femenino , Mucosa Gástrica/microbiología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Infecciones por Helicobacter/cirugía , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/patogenicidad , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Escisión del Ganglio Linfático , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma de Células B de la Zona Marginal/patología , Linfoma de Células B de la Zona Marginal/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Epiplón/cirugía , Cooperación del Paciente , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Virulencia
7.
Clin Ter ; 159(6): 421-5, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19169602

RESUMEN

Psoriasis is a multifaceted disorder with psychosocial and physical aspects that negatively impact the quality of life. Strategies of treatment must address both rapid control of the disease and maintenance of benefits. For short and long-term control of localized psoriasis, recent data support the combined use of topical corticosteroids and either calcipotriene or tazarotene which seem to be the most effective approach. For generalized disease, UVB treatment provides the safest means of achieving long-term control of the disease. Acitretin is a very helpful adjunct for improving the efficacy of phototherapy. For patients with severe, refractory disease, methotrexate may be most effective while cyclosporine may be most valuable for patients needing rapid, short-term improvement. Other molecules, with different pharmacological properties, are actually under consideration. Herein it is reported a case of a 55 year old male, who refers, 2 weeks after the fi rst cycle of oncologic therapy with gemcitabine and cisplatin for a lung neoplasm, about the complete remission of the psoriasis on both fingernails and scalp, suffered since almost ten years. Three months after the fortuitous detection of the psoriasis disappearance, there is no further evidence of psoriatic lesions.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Psoriasis/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Cisplatino/administración & dosificación , Cisplatino/farmacología , Daño del ADN , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Humanos , Inmunosupresores/uso terapéutico , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/psicología , Masculino , Persona de Mediana Edad , Terapia PUVA , Psoriasis/complicaciones , Psoriasis/psicología , Psoriasis/terapia , Estrés Psicológico/complicaciones , Terapia Ultravioleta , Gemcitabina
8.
Clin Ter ; 159(6): 457-62, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19169609

RESUMEN

During the last 20 years Helicobacter pylori (Hp) has been, undoubtly, the star of gastroenterology and microbiology, so much to deserve the "Nobel prize 2005" for biology and medicine to its discoverers. More recently, an increased interest arised on Hp and its linkages with other medical fi elds such as immunology, surgery and dentistry. The outcome of the pathologies due to such bacterium is dependent on many factors, including bacterial genotype, host physiology and genetics, and environmental factors such as diet. In spite of its clear involvement in some pathologies like acute and chronic gastritis, peptic ulcer and gastric cancer, very little is known about another pathology recently proved to be closely associated to the infection by Hp: the gastric MALToma, which account for 7% of all newly diagnosed non-Hodgkin's lymphoma. The chronic infection of the gastric mucosa from Helicobacter pylori primes a complex pathogenic process which could determine the onset of the gastric cancer through some intermediary steps. On these bases, in 1994, the International Agency for Cancer Research (IARC) defined this bacterium a "class I carcinogenic agent" for gastric cancer. The MALT lymphomas are the most frequent lymphoid neoplasms of the digestive tract; we can also observe other and more rare lymphomatous tumours with specific clinical patterns, like the T-lymphoma associated with lymphomatous polyposis and enteropathy. The development of gastric lymphomas is usually preceded by the acquisition of lymphatic tissue, after inflammatory stimuli and particularly after the infection from Hp, which organizes itself with the characteristics of the MALT. Recently, a number of papers have highlighted the remarkable efficacy of Hp eradicating therapy in patients with low-grade MALT lymphoma of the stomach without other modalities, e.g. surgery and systemic chemotherapy. The aim of this study is to be helpful for a comprehensive understanding the possible connections between Hp and gastric MALT lymphoma, evaluating the best therapy strategies, surgical and non surgical, actually available for its treatment.


Asunto(s)
Gastritis/tratamiento farmacológico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/patogenicidad , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Neoplasias Gástricas/tratamiento farmacológico , Antibacterianos/uso terapéutico , Antiulcerosos/uso terapéutico , Antineoplásicos/uso terapéutico , Claritromicina/uso terapéutico , Terapia Combinada , Placa Dental/microbiología , Diagnóstico por Imagen , Progresión de la Enfermedad , Sinergismo Farmacológico , Quimioterapia Combinada , Gastrectomía , Mucosa Gástrica/inmunología , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis/inmunología , Gastritis/microbiología , Infecciones por Helicobacter/inmunología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/fisiología , Humanos , Linfoma de Células B de la Zona Marginal/diagnóstico , Linfoma de Células B de la Zona Marginal/etiología , Linfoma de Células B de la Zona Marginal/microbiología , Linfoma de Células B de la Zona Marginal/radioterapia , Linfoma de Células B de la Zona Marginal/cirugía , Pronóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/etiología , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/cirugía , Subgrupos de Linfocitos T/inmunología
9.
Clin Ter ; 158(5): 409-19, 2007.
Artículo en Italiano | MEDLINE | ID: mdl-18062347

RESUMEN

AIM: The aim of the present study is to obtain comprehensive epidemiological data of the incidence of oral and dental health conditions in an Italian homogeneous population of schoolchildren. MATERIALS AND METHODS: The study has been performed on schoolchildren born, living and attending the primary school in Matera, Basilicata, Southern Italy. Such data have been compared with the alimentary habits of the participants to the study, as well as with the social-economic family situations and with the social-environmental data. RESULTS: The data show a marked difference in the habits of oral hygiene, and in the health status of the oral structures also, based on both the sex and the environment of life. CONCLUSIONS: Such differences in the prevalence of caries among various urban areas and the behavioural habits related to sex and age ratios may be very useful findings for future regional prevention programs.


Asunto(s)
Caries Dental/epidemiología , Conducta Alimentaria , Higiene Bucal/estadística & datos numéricos , Pobreza , Clase Social , Población Urbana/estadística & datos numéricos , Niño , Femenino , Humanos , Incidencia , Italia/epidemiología , Masculino , Higiene Bucal/métodos , Prevalencia , Salud Urbana/estadística & datos numéricos
10.
Clin Ter ; 158(4): 349-53, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17953287

RESUMEN

The term gastroesophageal reflux refers to the regurgitation of gastric material into the oesophagus. When the reflux is accompanied by inflammation of the oesophageal mucosa and extra-oesophageal symptoms the complaint is classified as a pathological condition called gastroesophageal reflux disease (GERD). GERD is caused by backward expulsion of the gastric content into the oesophagus. It is characterized by a complex clinical picture that may include lesions of the oesophageal mucosa and lesions of a different nature and severity of the respiratory and stomatognathic apparatus. GERD is considered to be a proteiform complaint induced by many different pathogenetic mechanisms resulting in a wide spectrum of clinical and morphological manifestations secondary to the reflux. Among extra-oesophageal manifestations, those affecting the dental structures are particularly important, owing to their aesthetic and functional implications on the stomatognathic apparatus. The Authors present a recently observed and treated case of GERD with associated severe aesthetic lesions of the frontal teeth. The currently available treatment options for the primary disease are examined, as well as the possible forms of conservative treatment of the affected teeth.


Asunto(s)
Reflujo Gastroesofágico/complicaciones , Erosión de los Dientes/etiología , Femenino , Reflujo Gastroesofágico/fisiopatología , Reflujo Gastroesofágico/terapia , Humanos , Persona de Mediana Edad , Erosión de los Dientes/fisiopatología , Erosión de los Dientes/terapia
11.
Int J Dent Hyg ; 5(3): 187-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17615029

RESUMEN

INTRODUCTION: Giardiasis, or Giardia lamblia infection, is the most common parasitosis of the human digestive tract. It is highly contagious and mostly occurs in warm climates. Children are especially susceptible to infection. MICROBIOLOGICAL FEATURES: The infection can sporadically occur anywhere and waterborne outbreaks have been reported in some countries. Hence, the prevention of giardiasis depends on proper sanitation. Once ingested through contaminated water, Giardia cysts adhere to the intestinal surface. The parasite feeds on the mucous secretions of the intestine and may produce severe infections which can interfere with nutrient absorption. Symptoms in affected individuals usually include diarrhoea, dehydration, stomach cramps, gas, and weight loss. DIAGNOSIS: Diagnosis is based on the detection of cysts in fecal samples. Treatment includes the use of metronidazole and other drugs that are effective in clearing the infection within a few days. CASE REPORT: We report the recent case of a patient with Giardiasis who received dental hygiene procedures and discuss the interventions required in consideration of the patient's concomitant heart condition.


Asunto(s)
Atención Dental para Enfermos Crónicos , Profilaxis Dental , Giardiasis/complicaciones , Insuficiencia Cardíaca/complicaciones , Trasplante de Corazón , Adulto , Humanos , Masculino
12.
Clin Ter ; 157(6): 541-8, 2006.
Artículo en Italiano | MEDLINE | ID: mdl-17228854

RESUMEN

Periodontitis is a condition of suffering of gingival and periodontal tissues. To the light of the available knowledges till now on the pathogenetic mechanisms of such affection is possible to affirm that the different risk factors can influence onset of it, evolution and therapeutic possibility. In the examination of the risk factors in the development of the periodontal pathology the effects of the systemic conditions on the health of the oral cavity has been considered, as well as the influence of the periodontal pathology on the onset and on the evolution of several systemic pathologies and related to some physiological conditions (e.g. the pregnancy).


Asunto(s)
Periodontitis , Adulto , Enfermedades Cardiovasculares/etiología , Complicaciones de la Diabetes , Endotoxinas , Femenino , Infecciones por VIH/complicaciones , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Osteoporosis/complicaciones , Periodontitis/complicaciones , Periodontitis/etiología , Embarazo , Complicaciones del Embarazo , Factores de Riesgo , Fumar/efectos adversos , Estrés Psicológico/complicaciones
13.
Clin Ter ; 156(5): 227-30, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16382971

RESUMEN

During the last years the importance of the correct nutritional assessment as a part of the therapeutic process of the human pathologies has a greatly increased relevance. Still more in oncology, such relationship among nutritional assessment and good result of the therapeutic treatment have a fundamental importance. Among the neoplastic diseases those of the head and the neck result to be particularly aggressive, both for their nature and for the particular anatomical organization of such body areas, and the affected patients also need a precise evaluation of the nutritional assessment to obtain an optimal therapeutic result. On the basis of such premises and to their own clinical experience, the authors describe the main nutritional problems of the patients with tumours of the head and the neck and the possible therapeutic solutions.


Asunto(s)
Neoplasias de Cabeza y Cuello/terapia , Desnutrición/prevención & control , Estado Nutricional , Apoyo Nutricional , Nutrición Enteral , Neoplasias de Cabeza y Cuello/fisiopatología , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Desnutrición/fisiopatología , Fenómenos Fisiológicos de la Nutrición , Necesidades Nutricionales , Nutrición Parenteral , Factores de Riesgo
14.
Minerva Stomatol ; 48(12): 591-4, 1999 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-10822711

RESUMEN

BACKGROUND: The present study analyzes the position of mental foramen, in order to research possible correlations with other mandibular parameters. METHODS: The study has been conducted on 76 dry mandibles, for each mandible we have measured the exact position of the mental forum respect the other mandibular parameters. Both linear and angular relations and misurations have been made. RESULTS AND CONCLUSIONS: The results obtained confirm that the mental foramen maintains its position by increasing GoGn. The results did not show particularly significant aspects in comparison with the literature on the subject, thus confirming other authors' opinion.


Asunto(s)
Mandíbula/anatomía & histología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antropometría , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad
15.
Minerva Stomatol ; 48(12): 609-14, 1999 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-10822713

RESUMEN

BACKGROUND: Aim of this study is to improve the in vivo knowledge about the real effects and the physiologic repair by a detached stitches silk suture in the 8th zone. METHODS: The study has been carried out on 44 patients submitted to surgical extraction of the impacted 8th (19 upper and 25 lower) teeth. RESULTS: Clinical and histological controls have demonstrated the usefulness of this suture procedure, since it gives a good histological reaction and in easy and safe. CONCLUSIONS: Histological and clinical results have confirmed the usefulness of silk suture, presenting however the inconvenience of stitches removal and bacterial plaque on the surgical wound.


Asunto(s)
Boca/cirugía , Técnicas de Sutura , Cicatrización de Heridas , Adolescente , Adulto , Femenino , Humanos , Masculino , Procedimientos Quirúrgicos Orales
16.
Minerva Stomatol ; 48(12): 615-9, 1999 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-10822714

RESUMEN

BACKGROUND: This study aims to identify the main oral lesions caused by the use of chemotherapeutic agents pre- and post-transplant in malignant hemopathologies and to highlight the importance of dental prevention during this treatment in order to reduce and, if possible, avoid the resulting local and systemic complications. METHODS: Twenty-five patients were controlled, monitored and prepared to undergo the necessary chemo- and radiotherapy, as well as bone marrow transplantation in the majority of cases under the best possible oral conditions. RESULTS: The most commonly detected secondary lesions were reactions to cyclophosphamide and/or methotrexate. In general, this mucositis appeared 5-7 days after treatment and continued for 1-2 weeks before regressing without residue. Another post-radiotherapeutic complication observed was xerostomy. CONCLUSIONS: Lastly, it is important to underline that patients receiving correct dental infection preventive treatment showed fewer tertiary lesions than those who did not undergo the same procedure.


Asunto(s)
Antineoplásicos/efectos adversos , Leucemia/complicaciones , Enfermedades de la Boca/etiología , Enfermedades de la Boca/terapia , Adulto , Trasplante de Médula Ósea , Femenino , Humanos , Leucemia/terapia , Masculino , Persona de Mediana Edad , Radioterapia/efectos adversos
17.
Minerva Stomatol ; 48(12): 633-7, 1999 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-10822717

RESUMEN

The study aimed to evaluate the healing of intraoral surgical wounds sutured with alpha-cyanoacrylate and silk in clinical and histological terms. Forty-four patients were checked 7 and 14 days after surgery. An incisional biopsy was made at the level of the discharge cut and histological tests were performed on the fragment. On the basis of the results, the authors affirm that in some areas (upper eighths), alpha-cyanoacrylate plays a useful role and simplifies the suture technique. On the contrary, this material was not sufficiently reliable in areas subject to excessive traction (lower eighths).


Asunto(s)
Procedimientos Quirúrgicos Orales , Técnicas de Sutura , Adolescente , Adulto , Cianoacrilatos , Femenino , Humanos , Masculino
18.
J Biol Chem ; 268(12): 8569-73, 1993 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-8473302

RESUMEN

Lipoprotein(a) levels in the plasma are strongly correlated with atherosclerotic coronary artery disease. Although the mechanism of this effect is not known, the interaction of lipoprotein(a) with macrophages may be important. Previous work has shown that macrophages in culture internalize and degrade native lipoprotein(a) poorly. In the present study, the interaction of Lp(a) with mouse peritoneal and human monocyte-derived macrophages that were cholesterol-loaded, such as occur in atheromata, was investigated. 125I-Lp(a) degradation was increased 4-5-fold in macrophages that had been loaded with cholesterol by incubation with acetyl-LDL for 2-4 days. The enhanced degradation of Lp(a) by foam cells was chloroquine-sensitive and dependent upon the presence of calcium in the extracellular medium. Incubation of the macrophages with acetyl-LDL plus an inhibitor of acyl CoA:cholesterol acyltransferase, which increased the free cholesterol content and decreased the cholesteryl ester content of the cells, resulted in an even greater up-regulation of 125I-Lp(a) degradation (8-23-fold over control macrophages). The interaction of Lp(a) with cholesterol-loaded macrophages involved the apoprotein(a) moiety of Lp(a) since 125I-apoprotein(a), but not 125I-Lp(a-), was degraded to a much greater extent by foam cells compared to control macrophages. The uptake and degradation of Lp(a) in foam cells was not mediated by LDL, scavenger, LDL receptor-related protein (LRP), or plasminogen receptors. Thus, cholesterol loading of macrophages markedly enhances the internalization and lysosomal degradation of Lp(a) and apo(a) by a calcium-dependent receptor activity different from known lipoprotein receptors.


Asunto(s)
Apolipoproteínas A/metabolismo , Colesterol/metabolismo , Lipoproteína(a)/metabolismo , Macrófagos/metabolismo , Animales , Sitios de Unión , Células Cultivadas , Femenino , Células Espumosas/metabolismo , Humanos , Ratones , Ratones Endogámicos ICR , Monocitos/metabolismo , Peritoneo/citología , Conejos , Esterol O-Aciltransferasa/metabolismo
19.
Arterioscler Thromb ; 13(2): 264-75, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8427861

RESUMEN

This report explores the hypothesis that massive cholesteryl ester (CE) accumulation in macrophages, such as that occurring in atheroma foam cells, results in changes in the expression or modification of specific cellular proteins. Two-dimensional (2-D) gel electrophoretic patterns of metabolically labeled cellular proteins from mouse peritoneal macrophages that were loaded with CE (through incubation with acetylated low density lipoprotein [acetyl-LDL] for 4 days) were compared with those of control macrophages. Densitometric analysis of 2-D gel autoradiograms from the cell lysates revealed statistically significant changes in seven cellular proteins (five decreases and two increases). The changes in protein expression (foam cell versus control) ranged from a 458 +/- 164% (p < 0.001) increase to a 35 +/- 34% (p < 0.001) decrease (n = 11). Incubation of macrophages with beta-very low density lipoprotein, which also increased the CE content of macrophages (albeit to a lesser extent than acetyl-LDL), resulted in changes in five of the seven proteins. In contrast, incubation of cells with LDL, fucoidan, or latex beads, none of which caused CE accumulation, did not lead to significant changes in four of these five proteins. One of these four proteins, which increased fourfold to fivefold in foam cells (M(r) = 49,000; isoelectric point of 6.8), was purified by preparative 2-D gel electrophoresis. Internal amino acid sequence of cyanogen bromide fragments of this protein as well as Western blot analysis identified this protein as an isoform of alpha-enolase. The increased expression of this alpha-enolase isoform, which was seen as early as day 2 of acetyl-LDL incubation of the macrophages, was diminished by including an inhibitor of cholesterol esterification during the acetyl-LDL incubation period. In conclusion, macrophage foam cell formation is associated with distinct changes in protein expression, including a marked increase in an isoform of alpha-enolase, suggesting a specific biological adaptation to CE loading.


Asunto(s)
Ésteres del Colesterol/metabolismo , Macrófagos/metabolismo , Fosfopiruvato Hidratasa/biosíntesis , Biosíntesis de Proteínas , Secuencia de Aminoácidos , Animales , Electroforesis en Gel Bidimensional , Femenino , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Ratones , Ratones Endogámicos ICR , Datos de Secuencia Molecular , Cavidad Peritoneal/citología
20.
J Biol Chem ; 266(34): 22866-71, 1991 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-1744079

RESUMEN

The macrophage scavenger receptor, a 220-kDa trimeric membrane glycoprotein, mediates the internalization of modified forms of low density lipoprotein (LDL) such as acetyl-LDL and oxidized-LDL and thus is likely to play a key role in atheroma macrophage foam cell formation. In addition, recent evidence suggests that the scavenger receptor may be an important macrophage binding site for lipopolysaccharide involved in lipopolysaccharide scavenging by macrophages. However, little is known about the regulation of this important receptor. We now report that the induction of scavenger receptor activity (as measured by acetyl-LDL stimulation of intracellular cholesterol esterification) seen in phorbol ester-differentiated THP-1 human macrophages was completely suppressed to the level seen in undifferentiated THP-1 monocytes by picomolar concentrations of transforming growth factor-beta 1 (TGF-beta 1). 125I-Acetyl-LDL degradation was inhibited in a dose-dependent manner by TGF-beta 1, with maximal inhibition (approximately 70%) occurring at 24 pM TGF-beta 1. Scatchard analysis revealed that TGF-beta 1 treatment resulted in a approximately 2-fold decrease in receptor number, and Northern blot analysis of RNA isolated from differentiated THP-1 macrophages demonstrated approximately 2-fold less scavenger receptor mRNA in TGF-beta 1-treated cells compared with that in macrophages not treated with TGF-beta 1. Since TGF-beta 1 is thought to be present in both atherosclerotic and inflammatory lesions, the above findings may have physiological relevance regarding the regulation of atheroma foam cell formation and/or the regulation of lipopolysaccharide clearance by macrophages.


Asunto(s)
Macrófagos/metabolismo , Proteínas de la Membrana , Receptores Inmunológicos/antagonistas & inhibidores , Receptores de Lipoproteína , Factor de Crecimiento Transformador beta/fisiología , Acetil-CoA C-Aciltransferasa/metabolismo , Northern Blotting , Diferenciación Celular , Línea Celular , Humanos , Lipoproteínas LDL/metabolismo , Macrófagos/citología , Receptores Depuradores , Receptores Depuradores de Clase B , Factores de Tiempo
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