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1.
ESMO Open ; 6(4): 100171, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34139487

RESUMO

BACKGROUND: Pheochromocytoma and paraganglioma (PPGL) have currently only limited treatment options available for patients in the metastatic phase (mPPGL) in either post-surgery or inoperable settings. However, these rare tumors overexpress somatostatin receptors and can thus be treated with peptide receptor radionuclide therapy (PRRT). We present data about our 10-year experience treating 46 consecutive mPPGL patients with 90Y-DOTATOC or 177Lu-DOTATATE. PATIENTS AND METHODS: All patients (20 men and 26 women, median age 52 years) showed positive scintigraphic imaging at 111In-octreotide or 68Ga-DOTATOC positron emission tomography/computed tomography (PET/CT). 90Y-DOTATOC was administered in 12 patients, with cumulative dosages ranging from 7.4 to 11 GBq, while 34 patients received 18.5 or 27.5GBq of 177Lu-DOTATATE. We used Southwest Oncology Group Response Evaluation Criteria in Solid Tumors criteria to evaluate treatment efficacy and Common Terminology Criteria for Adverse Events criteria to assess toxicity. The prognostic role of primary tumor site, hormone secretion, succinate dehydrogenase (SDHx) mutation, and metastatic involvement was also evaluated. RESULTS: Both 90Y-DOTATOC and 177Lu-DOTATATE PRRT were well tolerated by patients without significant renal or bone marrow toxicity. The median follow-up was 73 months (range 5-146 months). The overall disease control rate (DCR) was 80% [95% confidence interval (CI) 68.9% to 91.9%] with a mean five cycles of therapy. However, 177Lu-DOTATATE patients showed a longer median overall survival (mOS) than those receiving 90Y-Dotatoc and a better DCR when higher dosages were administered, even if a direct comparison was not carried out. Syndromic patients had a poorer mOS. SDHx mutations did not interfere with treatment efficacy. CONCLUSIONS: PRRT is safe and effective for the treatment of patients with progressive mPPGL, especially at higher dosages. The longer mOS of 177Lu-DOTATATE-treated patients in our protocols indicates the former radiopharmaceutical as the better candidate for further clinical application.


Assuntos
Neoplasias das Glândulas Suprarrenais , Tumores Neuroendócrinos , Paraganglioma , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/radioterapia , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paraganglioma/diagnóstico por imagem , Paraganglioma/radioterapia , Feocromocitoma/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Receptores de Somatostatina , Radioisótopos de Ítrio
2.
Eur J Nucl Med Mol Imaging ; 48(1): 87-94, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32588090

RESUMO

PURPOSE: To evaluate the clinical value of 68Ga-PSMA PET/CT negativity in patients with biochemical recurrent prostate cancer (BCR). METHODS: One hundred three BCR patients (median age, 70 years; median PSA, 0.47 ng/mL) with negative 68Ga-PSMA PET/CT, followed up for at least 1 year, were retrospectively identified in a database of 1003 consecutive patients undergoing 68Ga-PSMA PET/CT for BCR. Clinical recurrence (CR) was determined or excluded on follow-up imaging selected as per clinical practice. Clinical recurrence-free survival (CRFS) was computed from the date of negative 68Ga-PSMA PET/CT to the date of evident disease; frequencies of CRFS were described as per ISUP patient subset (subset 1: ISUP grades 1 and 2; subset 2: ISUP grade 3; subset 3: ISUP grades 4 and 5) and other conventional variables. RESULTS: In 57 patients out of 103 (55.3%), CR was detected in the prostatic fossa (45.6%), nodes (38.6%), and bone (15.8%). The median CRFS was 15.4 months (range, 12.1-20.5), with a CRFS at 12 months in 61.4% of cases (range, 50.9-70.4) whereas the 24-month CRFS was 34.8% (range, 24-45.8). ISUP subset 1 benefited from significantly longer CRFS compared to subset 2 and subset 3 (median CRFS, 20.5 months, 12.6 months, and 12.1 months, respectively). ISUP subset 3 had significantly poorer 24-month CRFS (9.3%) compared to subset 1 (47.8%) and subset 2 (33.5%). At the univariate and multivariate analyses, the ISUP subset was the only significant risk factor for clinical relapse; ISUP subset 3 and subset 2 patients held a higher risk of CR compared to subset 1 patients (HR of 2.75 [1.35-5.57] for subset 3 versus subset 1; HR of 2.08 [1.11-3.88] for subset 2 versus subset 1). CONCLUSION: 68Ga-PSMA PET/CT negativity in early BCR patients (PSA < 0.5 ng/mL) with low-grade primary prostate cancer (ISUP1 and 2) may support the exploration of a clinical surveillance approach in future prospective studies.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Idoso , Ácido Edético/análogos & derivados , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Oligopeptídeos , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Estudos Retrospectivos
3.
Eur J Nucl Med Mol Imaging ; 43(5): 839-851, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26596723

RESUMO

BACKGROUND: Peptide receptor radionuclide therapy (PRRT) is an effective method for treating neuroendocrine tumors (NETs). It is limited, however, in the prediction of individual tumor response and the precise and early identification of changes in tumor size. Currently, response prediction is based on somatostatin receptor expression and efficacy by morphological imaging and/or chromogranin A (CgA) measurement. The aim of this study was to assess the accuracy of circulating NET transcripts as a measure of PRRT efficacy, and moreover to identify prognostic gene clusters in pretreatment blood that could be interpolated with relevant clinical features in order to define a biological index for the tumor and a predictive quotient for PRRT efficacy. METHODS: NET patients (n = 54), M: F 37:17, median age 66, bronchial: n = 13, GEP-NET: n = 35, CUP: n = 6 were treated with (177)Lu-based-PRRT (cumulative activity: 6.5-27.8 GBq, median 18.5). At baseline: 47/54 low-grade (G1/G2; bronchial typical/atypical), 31/49 (18)FDG positive and 39/54 progressive. Disease status was assessed by RECIST1.1. Transcripts were measured by real-time quantitative reverse transcription PCR (qRT-PCR) and multianalyte algorithmic analysis (NETest); CgA by enzyme-linked immunosorbent assay (ELISA). Gene cluster (GC) derivations: regulatory network, protein:protein interactome analyses. STATISTICAL ANALYSES: chi-square, non-parametric measurements, multiple regression, receiver operating characteristic and Kaplan-Meier survival. RESULTS: The disease control rate was 72 %. Median PFS was not achieved (follow-up: 1-33 months, median: 16). Only grading was associated with response (p < 0.01). At baseline, 94 % of patients were NETest-positive, while CgA was elevated in 59 %. NETest accurately (89 %, χ(2) = 27.4; p = 1.2 × 10(-7)) correlated with treatment response, while CgA was 24 % accurate. Gene cluster expression (growth-factor signalome and metabolome) had an AUC of 0.74 ± 0.08 (z-statistic = 2.92, p < 0.004) for predicting response (76 % accuracy). Combination with grading reached an AUC: 0.90 ± 0.07, irrespective of tumor origin. Circulating transcripts correlated accurately (94 %) with PRRT responders (SD+PR+CR; 97 %) vs. non-responders (91 %). CONCLUSIONS: Blood NET transcript levels and the predictive quotient (circulating gene clusters+grading) accurately predicted PRRT efficacy. CgA was non-informative.


Assuntos
Biomarcadores Tumorais/sangue , Tumores Neuroendócrinos/sangue , Octreotida/análogos & derivados , RNA Mensageiro/sangue , Compostos Radiofarmacêuticos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromogranina A/sangue , Análise por Conglomerados , Feminino , Redes Reguladoras de Genes , Humanos , Masculino , Metaboloma , Pessoa de Meia-Idade , Tumores Neuroendócrinos/radioterapia , Octreotida/uso terapêutico , RNA Mensageiro/genética , Receptores de Peptídeos/metabolismo , Resultado do Tratamento
4.
Clin Radiol ; 65(7): 536-48, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20541653

RESUMO

2- [(18)F]-fluoro-2-deoxy-D-glucose (FDG) is the radiopharmaceutical most frequently used for clinical positron emission tomography (PET). However, FDG cannot be used for many oncological, cardiological, or neurological conditions, either because the abnormal tissue does not concentrate it, or because the tissues under investigation demonstrate high physiological glucose uptake. Consequently, alternative PET tracers have been produced and introduced into clinical practice. The most important compounds in routine practice are (11)C-choline and (18)F-choline, mainly for the evaluation of prostate cancer; (1)C-methionine for brain tumours; (118)F-DOPA ((18)F-deoxiphenilalanine) for neuroendocrine tumours and movement disorders; (68)Ga-DOTANOC (tetraazacyclododecanetetraacetic acid-[1-Nal3]-octreotide) and other somatostatin analogues for neuroendocrine tumours; 11C-acetate for prostate cancer and hepatic masses and 18F-FLT (3-deoxy-3-fluorothymidine) for a number of malignant tumours. Another impetus for the development of new tracers is to enable the investigation of biological processes in tumours other than glucose metabolism. This is especially important in the field of response assessment, where there are new agents that are targeted more specifically at angiogenesis, hypoxia, apoptosis and other processes.


Assuntos
Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos , Compostos Radiofarmacêuticos , Colina , Humanos , Metionina , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto
5.
EDTNA ERCA J ; 25(2): 9-11, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10531873

RESUMO

Several studies suggest that the 24 hour ambulatory blood pressure monitoring (ABPM) predicts left ventricular hypertrophy more accurately than conventional blood pressure measurement (CBPM) with mercury sphygmomanometer. We estimated the left ventricular mass by M-mode echocardiography in 58 patients on regular haemodialysis treatment during the midweek haemodialysis (HD) interval. ABPM was recorded during the 24 hours preceding the dialysis session and the average of values were compared with the average of the 13 pre HD CBPM recorded by nurses during the month preceding the echocardiography study. The two types of BP measurements correlated significantly with each other, (systolic BP r = 0.62; p < 0.001 and diastolic BP r = 0.74; p < 0.001). The correlation of left ventricular mass with pre-HD systolic BP was stronger (r = 0.54; p < 0.001) than with 24h-systolic BP (r = 0.33; p < 0.01). The overall accuracy of prediction was also similar (68% for pre HD-CBPM; 67% for 24h-ABPM). Measurements of diastolic BP did not correlate significantly with LVM. Our data suggest that 24h-ABPM does not offer any advantage over pre HD-CBPM in predicting left ventricular hypertrophy in HD patients.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertrofia Ventricular Esquerda/diagnóstico , Diálise Renal , Uremia/complicações , Idoso , Feminino , Humanos , Hipertrofia Ventricular Esquerda/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Uremia/terapia
6.
Salud ment ; 20(1): 50-5, ene.-mar. 1997.
Artigo em Espanhol | LILACS | ID: lil-227384

RESUMO

En este trabajo se llevó a cabo una revisión crítica de la bibliografía relacionada con los factores genéticos y cognoscitivos que influyen en la etiología del autismo. Inicialmente, hicimos una revisión de los diferentes aspectos teóricos, neuropsicológicos, genéticos y cognoscitivos que han desarrollado y definido el autismo como un trastorno infantil. Después se hizo una recopilación bibliográfica sobre las investigaciones relacionadas con los marcadores genéticos, X-frágil, serotonina y dopamina, involucrados en el desarrollo cognoscitivo del niño autista. Los resultados de las investigaciones etiológicas sobre el autismo, sugirieron que éste, es un trastorno caracterizado por un déficit cognoscitivo que entraña una retirada social y/o emocional. La relevancia de un estudio interdisciplinario radica en que los esfuerzos médicos, terapéuticos y en equipo son necesarios para el diagnóstico y tratamiento del niño autista


Assuntos
Humanos , Criança , Cognição , Transtorno Autístico/etiologia , Transtorno Autístico/genética
8.
J Lipid Res ; 37(3): 493-507, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8728313

RESUMO

We investigated in the chick whether the diet-induced changes of the hepatic content of cholesteryl esters (CE) influence the synthesis and the secretion of apoB- and apoA-I-containing lipoproteins. Control chicks received a low cholesterol diet for 2 (SD-1), 4 (SD-2), or 7 (SD-3) weeks; the chicks in the experimental groups received a cholesterol-rich diet for 2 weeks and were killed at the end of the cholesterol feeding (CH-F), and after 2 (CH-D) or 5 (CH-DD) weeks of a low cholesterol diet. Hepatic CE content in CH-F chicks was 30-fold that observed in controls, but returned to the control level after 5 weeks of cholesterol depletion (CH-DD). The incorporation of 35S-labeled amino acids into cell and medium apoB and apoA-I was measured in liver slices. Intracellular 35S-labeled apoB was similar in all groups whereas medium 35S-labeled apoB was 2-fold higher in CH-F than in controls (SD-1). Pulse-chase experiments showed that radioactive apoB secreted by CH-F chicks at 120 min of chase was 2 times that of SD-1 chicks. This increased secretion of apoB was not found in CH-D chicks. In CH-F chicks, the intracellular and medium 35S-labeled apoA-I were 2-fold the values found in controls (SD-1); apoA-I production returned to the control level only after 5 weeks of cholesterol depletion (CH-DD). The increased secretion of apoB and apoA-I in CH-F chicks was associated with an increased secretion of very low, intermediate, and low density lipoproteins containing newly synthesized apoB and apoA-I and of high density lipoproteins containing predominantly apoA-I. Thus, in response to hepatic CE accumulation induced by cholesterol feeding, a larger proportion of newly synthesized apoB is driven to the secretory pathway and more apoA-I is synthesized. This promotes an increased secretion of plasma lipoproteins that contribute to the removal of CE from the liver.


Assuntos
Apolipoproteína A-I/metabolismo , Apolipoproteínas B/metabolismo , Ésteres do Colesterol/metabolismo , Fígado/metabolismo , Animais , Apolipoproteína A-I/biossíntese , Apolipoproteína B-100 , Apolipoproteínas B/biossíntese , Northern Blotting , Peso Corporal , Centrifugação com Gradiente de Concentração , Galinhas , Colesterol/sangue , Colesterol na Dieta/administração & dosagem , Dieta , Lipoproteínas/sangue , Fígado/química , Masculino , Ácido Oleico/metabolismo , Tamanho do Órgão , Proteínas/metabolismo , RNA/metabolismo , Triglicerídeos/sangue
9.
J Lipid Res ; 35(11): 2019-31, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7868980

RESUMO

In the chick, the large cholesteryl ester (CE) store present in the liver during the last period of embryonic life increases at hatching and is rapidly depleted after 2-7 days of postnatal life. In this study we asked whether these changes were associated with variations in the hepatic production of apoB-containing lipoproteins. Liver slices taken from chicks at -3, 0 (hatching), 2, 4, 7, and 10 days of development were incubated with [35S]methionine in steady state incubations. ApoB production (cell + medium radioactivity) decreased from day -3 to day 0 (40%), increased at day 4 (54%), and decreased afterwards (45%). At day 4 the amount of 35S-labeled apoB-containing lipoproteins (VLDL-LDL) secreted into the medium was 1.7- and 1.5-times that found at days 0 and 7, respectively; the radioactivity incorporated into medium HDL (containing predominantly apoA-I) was 1.7-times that found at days 0 and 7. The incubation of liver slices with [3H]oleate showed that CE production at days 4 and 7 was 58% and 33%, respectively, of that found at day 0. The percentage of newly synthesized hepatic CE secreted into medium lipoproteins was 2.4%, 3.1%, and 2.2% at days 0, 4, and 7, respectively. The percentage of lipoprotein CE present in VLDL-LDL ranged from 38% at day 0 to 21% at day 7, and that present in HDL ranged from 62% at day 0 to 79% at day 7. To define whether the changes in the production of apoA-I- and apoB-containing lipoproteins were due to variations in apoB and apoA-I synthesis, the initial synthetic rate (pulse-labeling) and the mRNA content of these apolipoproteins were investigated. The initial apoB synthetic rate decreased 1.5-fold from day -3 to day 0, remained stable up to day 7, and decreased at day 10. Hepatic apoB mRNA followed a similar trend. The synthesis of apoA-I increased 2-fold from days -3/2 up to day 4 and did not change afterwards. In conclusion the increased hepatic CE content at hatching reflects a decreased production of apoB, while the depletion of CE observed from day 2 to day 7 is associated with an increased production of both apoB- and apoA-I-containing lipoproteins. The decreased apoB production at hatching is due to a decreased apoB synthesis whereas the increased apoB production at day 4 appears to be related to a post-translational event.


Assuntos
Apolipoproteínas B/biossíntese , Galinhas/crescimento & desenvolvimento , Ésteres do Colesterol/metabolismo , Fígado/crescimento & desenvolvimento , Animais , Apolipoproteína B-100 , Northern Blotting , Embrião de Galinha , Galinhas/metabolismo , Estradiol/sangue , Técnicas de Imunoadsorção , Lipídeos/sangue , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Fígado/embriologia , Fígado/metabolismo , Masculino , Metionina/metabolismo , Ácido Oleico , Ácidos Oleicos/metabolismo , Radioisótopos de Enxofre , Trítio
10.
Aging (Milano) ; 6(5): 381-90, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7893785

RESUMO

We have previously shown that the administration of a thromboxane A2 (TXA2) synthase inhibitor (FCE 22178) reduced the progression of glomerular lesions and proteinuria in MNS rats, an inbred strain which develops an age-related nephrotic syndrome. In the present study we investigated the effect of FCE 22178 on the plasma lipoproteins of MNS rats at 28 weeks of age (with mild proteinuria and moderate dyslipoproteinemia) and at 48 weeks of age (with heavy proteinuria and severe dyslipoproteinemia). Drug treatment reduced proteinuria (by 70% and 36% at 28 and 48 weeks of age, respectively) plasma cholesterol (by 36% and 27% at 28 and 48 weeks of age, respectively) and prevented the decrease of plasma albumin observed in untreated rats (C-MNS) 48 weeks old. In treated rats (T-MNS), the decrease of proteinuria was positively correlated with that of plasma cholesterol. FCE 22178 reduced the elevation in plasma HDL1 (by 17.4%) and HDL2 levels (by 30%), a key feature of nephrotic dyslipoproteinemia in the rat. From 28 to 48 weeks of age plasma apo A-I and apo E increased 217% and 128%, respectively, in C-MNS rats and 191% and 121%, respectively, in T-MNS rats. A significant increase of apo A-I/apo E ratio was found in C-MNS rats from 28 (2.28 +/- 0.36) to 48 weeks of age (3.84 +/- 0.9) but not in T-MNS rats. FCE 22178 altered the lipid composition of VLDL and HDL2 by reducing the content of cholesteryl esters and increasing that of free cholesterol and phospholipids. These findings suggest that the beneficial effect of FCE 22178 on the dyslipoproteinemia of nephrotic MNS rats is secondary to the amelioration in kidney function and to the reduction of proteinuria produced by this drug.


Assuntos
Hiperlipidemias/sangue , Imidazóis/farmacologia , Lipoproteínas/sangue , Naftalenos/farmacologia , Síndrome Nefrótica/sangue , Proteinúria/sangue , Tromboxano-A Sintase/antagonistas & inibidores , Envelhecimento , Animais , Apolipoproteínas A/sangue , Apolipoproteínas A/efeitos dos fármacos , Apolipoproteínas E/sangue , Apolipoproteínas E/efeitos dos fármacos , Peso Corporal , Modelos Animais de Doenças , Hiperlipidemias/tratamento farmacológico , Imidazóis/uso terapêutico , Metabolismo dos Lipídeos , Lipídeos/sangue , Lipoproteínas/efeitos dos fármacos , Lipoproteínas HDL/sangue , Lipoproteínas HDL/efeitos dos fármacos , Lipoproteínas LDL/sangue , Lipoproteínas LDL/efeitos dos fármacos , Masculino , Naftalenos/uso terapêutico , Síndrome Nefrótica/tratamento farmacológico , Proteinúria/tratamento farmacológico , Ratos , Ratos Endogâmicos
11.
J Lipid Res ; 32(10): 1675-87, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1797947

RESUMO

Rats of the Milan Normotensive Strain (MNS) develop a dyslipoproteinemia that is associated with a spontaneous, age-dependent and slowly progressive nephropathy characterized by proteinuria and hypoalbuminemia (nephrotic syndrome). We assumed that the MNS strain might be a suitable model for studying the features of nephrotic dyslipoproteinemia and its relationship with proteinuria, hypoalbuminemia, and hepatic apolipoprotein production. Plasma lipoproteins were investigated in MNS rats at various ages (4-48 weeks) and in another rat strain (Milan Hypertensive Strain, MHS), genetically related to MNS but free of nephropathy, that was used as control. In MNS rats, abnormal proteinuria was detectable at 20 weeks and increased 2-fold up to 34 weeks with no reduction of plasma albumin (compensated stage). During this stage we found increased levels of plasma cholesterol (+ 34%), high density lipoprotein-1 (HDL1) (+ 73%), and HDL2 (+ 31%) that were positively correlated with proteinuria but not with plasma albumin. The later stage (34-48 weeks) (nephrotic stage) was characterized by a further increase of proteinuria, moderate hypoalbuminemia (- 25%), a 2-fold increase of plasma cholesterol, triacylglycerols, low density lipoprotein (LDL), and HDL1, and a 1.2-fold increase of HDL2. In this stage the levels of LDL, HDL1, and HDL2 were positively correlated with proteinuria, and negatively correlated with plasma albumin. The most striking change in apolipoproteins was a progressive increase of the relative content of apoA-I in HDL (in 48-week-old MNS rats the A-I/E ratio was 3-fold that found in MHS rats) that was associated with a similar increase of plasma apoA-I. None of these lipoprotein changes were observed in age-matched MHS rats. At the end of the compensated stage, the hepatic levels of A-I, B, A-II, and albumin mRNA were 5.3-, 3.5-, 1.3-, and 2.0-fold, respectively, those found in age-matched MHS rats. During the nephrotic stage, albumin mRNA continued to increase, whereas A-I, B, and A-II mRNAs decreased toward the levels found in age-matched MHS rats. Thus, nephrotic dyslipoproteinemia in MNS rats starts to develop in the compensated stage before the onset of hypoalbuminemia, is characterized by an early elevation of HDL1 + HDL2, and is associated with an increased content of hepatic mRNAs of some apolipoproteins, especially apoA-I. The slow progression of nephrotic syndrome with the long-standing proteinuria and no reduction in plasma albumin renders the MNS strain the most suitable animal model for the study of the effect of proteinuria on plasma lipoprotein metabolism.


Assuntos
Lipoproteínas/sangue , Síndrome Nefrótica/metabolismo , Albuminas/metabolismo , Animais , Animais Recém-Nascidos , Apolipoproteínas/metabolismo , Doença Crônica , Eletroforese em Gel de Poliacrilamida , Cinética , Lipídeos/sangue , Fígado/metabolismo , Masculino , Síndrome Nefrótica/sangue , Síndrome Nefrótica/complicações , Proteinúria/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos
12.
J Biol Chem ; 266(12): 7714-20, 1991 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-1708390

RESUMO

Chick skin slices were incubated with [35S]methionine and labeled apoA-I was immunoprecipitated from incubation medium and tissue homogenate. ApoA-I accounted for approximately 13 and 2.5% of radioactive medium and cell proteins, respectively. After ultracentrifugation of the medium, 55% of labeled apoA-I was found as a constituent of lipoproteins (d less than 1.210 g/ml) and 45% in a lipid-poor form (1.210-1.260 g/ml). To ascertain whether this large proportion of lipid-poor apoA-I was due to a dissociation of this peptide from medium lipoproteins during ultracentrifugation, labeled incubation medium was applied to an anti-chick apoA-I immunoaffinity column. The material bound to the column was analyzed by nondenaturing polyacrylamide gradient gel electrophoresis and found to contain three subpopulations of lipoproteins with a particle size of 12, 11, and 9 nm, respectively. The radioactivity of these subpopulations accounted for 82% of total radioactive medium apoA-I. ApoA-I was localized by immunohistochemistry in the viable cells of the epidermis and in the stratum corneum. Rat skin slices were found to synthesize and secrete apoE but no apoA-I. ApoA-I and apoE secreted by chick and rat skin, respectively, may play a role in the secretion of lipids from the differentiating keratinocytes and thus contribute to the formation of the hydrophobic barrier of the skin.


Assuntos
Apolipoproteínas A/biossíntese , Pele/metabolismo , Animais , Apolipoproteína A-I , Apolipoproteínas A/genética , Apolipoproteínas A/metabolismo , Apolipoproteínas E/biossíntese , Apolipoproteínas E/metabolismo , Northern Blotting , Galinhas , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Imuno-Histoquímica , Masculino , Hibridização de Ácido Nucleico , RNA/análise , Ratos , Ratos Endogâmicos
13.
J Lipid Res ; 31(3): 417-27, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2341807

RESUMO

This study was designed to investigate: a) whether multiple forms of apoB are present in chick plasma lipoproteins; and b) which forms of apoB are produced in vitro by liver and intestine at various stages of pre- and post-natal development. Plasma lipoproteins of d less than 1.019 g/ml, isolated from fasted and nonfasted chicks, contained exclusively the high molecular weight apoB form (apoB-100) that comigrated with human and rat apoB-100 on SDS-PAGE gel. No apoB-48 was detected either in overloaded Coomassie blue-stained gels or after immunoblotting. ApoB-100 but no apoB-48 was found in portomicrons, the triglyceride-rich lipoproteins equivalent to chylomicrons, that in the chick are transported via the porto-mesenteric venous system. To ascertain whether a minute amount of apoB-48 was present in chick plasma, [35S]methionine was injected intraduodenally and the 35S-labeled d less than 1.019 g/ml plasma lipoproteins were isolated 45 min later from the systemic and the porto-mesenteric circulation. Only apoB-100 was found to be labeled in these lipoproteins. Cholesterol feeding did not induce the appearance of apoB-48 in plasma despite a marked accumulation of cholesterol-rich d less than 1.040 g/ml lipoproteins in the plasma. In vitro synthesis of apoB forms was studied in liver and intestinal slices isolated from chick embryos (8 and 5 days before hatching), newly hatched chicks (2 and 7 days after hatching), and young chicks (21 days old) that were incubated in the presence of [35S]methionine. At each stage of development, liver slices secreted predominantly apoB-100. Intestinal slices of newly hatched and young chicks secreted two forms of apoB: apoB-100 and an additional form with an electrophoretic mobility similar to rat plasma apoB-95. No apoB-48 was synthesized or secreted by the intestine. Our results indicate that the absence of apoB-48 in chick plasma reflects the lack of synthesis of this peptide in the intestine. It is conceivable that in chick intestine the recently described molecular mechanism responsible for the co/posttranscriptional modification of apoB mRNA leading to the formation of apoB-48 is lacking or defective.


Assuntos
Apolipoproteínas B/sangue , Galinhas/sangue , Lipoproteínas/sangue , Animais , Apolipoproteína B-48 , Apolipoproteínas B/biossíntese , Apolipoproteínas B/metabolismo , Embrião de Galinha , Colesterol na Dieta/administração & dosagem , Eletroforese em Gel de Poliacrilamida , Immunoblotting , Mucosa Intestinal/metabolismo , Lipoproteínas/biossíntese , Lipoproteínas/metabolismo , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Fígado/metabolismo , Triglicerídeos/metabolismo
14.
Odontol Chil ; 37(1): 169-74, 1989 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-2641953

RESUMO

The purpose of the present investigation was to study the occurrence and degree of severity of the actinic cheilitis in a sample of 566 artisan fishermen of Valparaíso, Chile. The condition was found in 43% of the sample, the degree of severity was an 8% for the acute expression and a 35% for the chronic type of the disease. A direct relationship between the number of years spent on sun exposure and the degree of severity of the vermillion alterations was found, being the patients between 16 and 45 years old the group most severely involved, a finding similar to the data reported in the current literature. The prone complexion was the fair one: those fishermen with blond or red hair, blue or green eyes and fair skin showed both clinical and histopathologically early disturbances of degenerative nature in the collagenous component of the connective tissue and in the epithelial surface.


Assuntos
Queilite/epidemiologia , Raios Ultravioleta/efeitos adversos , Adulto , Queilite/etiologia , Queilite/patologia , Chile/epidemiologia , Cor de Olho , Pesqueiros , Cor de Cabelo , Humanos , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Prevalência , Luz Solar/efeitos adversos
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