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1.
J Hosp Infect ; 147: 133-145, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423132

RESUMO

BACKGROUND: Healthcare-associated infections (HAIs) burden healthcare globally. Amid the SARS-CoV-2 pandemic, intensified infection control measures, such as mask usage and hand hygiene, were implemented. AIM: To assess the efficacy of these measures in preventing HAIs among hospitalized patients. METHODS: Using the PICO framework (Population, Intervention, Comparison, Outcome), the study focused on hospitalized patients and the effectiveness of anti-COVID-19 measures in preventing HAIs. A systematic review of literature published in 2020-2022 was conducted, examining interventions such as mask usage, hand hygiene, and environmental cleaning. FINDINGS: This systematic review analysed 42 studies: two in 2020, 21 in 2021, and 19 in 2022. Most studies were from high-income countries (28). Most studies (30 out of 42) reported a reduction in HAIs after implementing anti-COVID-19 measures. Gastrointestinal infections and respiratory tract infections showed significant reduction, unlike bloodstream infections and urinary tract infections. Some wards, like cardiology and neurology, experienced reduced HAIs, unlike intensive care units and coronary care units. There was an increase in studies reporting no effect of hygiene measures on HAIs in 2022, eventually indicating a shift in effectiveness over time. CONCLUSION: Anti-COVID-19 measures have shown selective efficacy in preventing HAIs. The study emphasizes the need for context-specific strategies and increased focus on regions with limited resources. Continued research is essential to refine infection control practices, especially in high-risk settings.


Assuntos
COVID-19 , Infecção Hospitalar , Controle de Infecções , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/epidemiologia , Controle de Infecções/métodos , SARS-CoV-2 , Higiene das Mãos , Máscaras/estatística & dados numéricos
2.
J Endocrinol Invest ; 45(10): 1935-1944, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35680695

RESUMO

OBJECTIVES: Pheochromocytomas are rare tumors which can present with heterogeneous secretion profiles, clinical manifestations, and radiologic appearance. Under a histopathological point of view, they can be characterized as more or less aggressive with the Pheochromocytoma of the Adrenal gland Scaled Score (PASS) and the Grading system for Adrenal Pheochromocytoma and Paraganglioma (GAPP) score. The aim of this study is to analyze the texture analysis characteristics of pheochromocytoma and identify whether the texture analysis can yield information aiding in the diagnosis and the characterization of those tumors. METHODS: Radiological, biochemical, and histopathological data regarding 30 consecutive patients with histologically confirmed pheochromocytoma were analyzed. Images obtained in the unenhanced, late arterial, venous, and delayed phases were used for the texture analysis. RESULTS: Urinary epinephrine and metanephrine levels showed a significant correlation (R2 = 0.946; R2 = 699) in the multivariate linear model with texture features, as well as Ki-67 (R2 = 0.397), PASS score (R2 = 0.182), GAPP score (R2 = 0.705), and cellularity showed a significant correlation (R2 = 0.389). The cluster analysis based on radiomic features resulted in 2 clusters, with significative differences in terms of systolic and diastolic blood pressure values at the time of diagnosis (p = 0.025), GAPP score (4 vs 6, p = 0.05), histological pattern (1-2, p = 0.039), and comedonecrosis (0% vs 50%, p = 0.013). CONCLUSION: In conclusion, our study provides the proof of concept for the use of texture analysis on contrast-enhanced CT images as a noninvasive, quantitative tool for helping in the characterization of the clinical, biochemical, and histopathological features of pheochromocytoma.


Assuntos
Neoplasias das Glândulas Suprarrenais , Paraganglioma , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/patologia , Humanos , Metanefrina , Paraganglioma/patologia , Feocromocitoma/diagnóstico por imagem , Feocromocitoma/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
4.
J Endocrinol Invest ; 43(9): 1197-1204, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32062826

RESUMO

BACKGROUND: Adrenal lipid-poor adenomas (LPA) are defined by high unenhanced density (≥ 10 HU), and absolute and relative contrast medium washout > 60% and > 40%, respectively, at computerized tomography (CT). To date, no thorough histopathological characterization has been performed in those frequent lesions (one-third of adrenal adenomas). Our aim was to analyze the histopathological characteristics of adrenal LPA. METHODS: Patients with LPA (n = 57) were selected among consecutive subjects referred for an adrenal incidentaloma or ACTH-independent Cushing syndrome. FluoroDeoxyGlucose-Positron Emission Tomography (FDG-PET) was performed in 37 patients. In patients treated by adrenalectomy (n = 17), Weiss score and Lin-Weiss-Bisceglia score (in tumors composed entirely or predominantly of oncocytes) were calculated. RESULTS: Radiological parameters did not differ among patients with ACTH-independent Cushing syndrome (n = 6) and those with adrenal incidentalomas associated with primary aldosteronism (n = 2), autonomous cortisol secretion (n = 14), or non-functioning (n = 35). Patients treated by adrenalectomy had larger tumors (28.9 ± 11.2 vs 17.3 ± 8.4 mm, P < 0.001), higher CT unenhanced density (29.1 ± 11.0 vs 23.1 ± 9.0 HU, P = 0.043), and FDG-PET adrenal uptake (9.0 ± 6.4 vs 4.4 ± 2.3 SUV, P = 0.003) than non-operated ones. Oncocytic features > 75% of the tumor were detected in 12/17 cases (70.6%). Five of those showed borderline-malignant histopathological characteristics by Lin-Weiss-Bisceglia score. Among remaining non-oncocytic tumors, 1/5 had a Weiss score ≥ 3. Overall, 6/17 tumors (35.3%) had borderline-malignant potential. Radiological parameters were similar between patients with benign and borderline-malignant tumors. CONCLUSIONS: Adrenal LPA are a heterogeneous group of tumors, mostly composed of oncocytomas. Up to 1/3 of those tumors may have a borderline-malignant potential at histopathology.


Assuntos
Adenoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico , Síndrome de ACTH Ectópico/diagnóstico , Síndrome de ACTH Ectópico/etiologia , Síndrome de ACTH Ectópico/metabolismo , Síndrome de ACTH Ectópico/patologia , Adenoma/metabolismo , Adenoma/patologia , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Biópsia , Estudos de Coortes , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/etiologia , Síndrome de Cushing/metabolismo , Síndrome de Cushing/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Itália , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
6.
Eur J Nucl Med Mol Imaging ; 45(5): 751-758, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29192364

RESUMO

AIM: During our daily clinical practice using 11C-Choline PET/CT for restaging patients affected by relapsing prostate cancer (rPCa) we noticed an unusual but significant occurrence of hypodense hepatic lesions with a different tracer uptake. Thus, we decided to evaluate the possible correlation between rPCa and these lesions as possible hepatic metastases. MATERIALS AND METHODS: We retrospectively enrolled 542 patients diagnosed with rPCa in biochemical relapse after a radical treatment (surgery and/or radiotherapy). Among these, patients with a second tumor or other benign hepatic diseases were excluded. All patients underwent 11C-Choline PET/CT during the standard restaging workup of their disease. We analyzed CT images to evaluate the presence of hypodense lesions and PET images to identify the relative tracer uptake. In accordance to the subsequent oncological history, five clinical scenarios were recognized [Table 1]: normal low dose CT (ldCT) and normal tracer distribution (Group A); evidence of previously unknown hepatic round hypodense areas at ldCT with normal rim uptake (Group B); evidence of previously known hepatic round hypodense areas at ldCT stable over time and with normal rim uptake (Group C); evidence of previously known hepatic round hypodense areas at ldCT, in a previous PET/CT scan, with or without rim uptake and significantly changing over time in terms of size and/or uptake (Group D); evidence of hepatic round hypodense areas at ldCT with or without rim uptake confirmed as prostate liver metastases by histopathology, triple phase ceCT, ce-ultra sound (CEUS) and clinical/biochemical evaluation (Group E). We evaluated the correlation with PSA level at time of scan, rim SUVmax and association with local relapse or non-hepatic metastases (lymph nodes, bone, other parenchyma). RESULTS: Five hundred and forty-two consecutive patients were retrospectively enrolled. In 140 of the 542 patients more than one 11C-choline PET/CT had been performed. A total of 742 11C-Choline PET/CT scans were analyzed. Of the 542 patients enrolled, 456 (84.1%) had a normal appearance of the liver both at ldCT and PET (Group A). 19/542 (3,5%) belonged to Group B, 13/542 (2.4%) to Group C, 37/542 (6.8%) to Group D and 18/542 (3.3%) to Group E. Mean SUVmax of the rim was: 4.5 for Group B; 4.2 for Group C; 4.8 for Group D; 5.9 for Group E. Mean PSA level was 5.27 for Group A, 7.9 for Group B, 10.04 for Group C, 10.01 for Group D, 9.36 for Group E. Presence of positive findings at 11C-Choline PET/CT in any further anatomical area (local relapse, lymph node, bone, other extra hepatic sites) correlated with an higher PSA (p = 0.0285). In both the univariate and multivariate binary logistic regression analyses. PSA, SUVmax of the rim, local relapse, positive nodes were not associated to liver mets (Groups D-E) (p > 0.05). On the contrary, a significant correlation was found between the presence of liver metG (group D-E) and bone lesions (p= 0.00193). CONCLUSION: Our results indicate that liver metastases in relapsing prostate cancer may occur frequently. The real incidence evaluation needs more investigations. In this case and despite technical limitations, Choline PET/CT shows alterations of tracer distribution within the liver that could eventually be mistaken for simple cysts but can be suspected when associated to high trigger PSA, concomitant bone lesions or modification over time. In this clinical setting an accurate analysis of liver tracer distribution (increased or decreased uptake) by the nuclear medicine physician is, therefore, mandatory.


Assuntos
Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Carbono , Colina , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
Gastroenterol Res Pract ; 2017: 7872519, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29213282

RESUMO

PURPOSE: To evaluate the role of the activation of mTOR (phosphorylated mTOR, p-mTOR) and the expression SSTR2A and IGF-1R as prognostic factor in well-differentiated neuroendocrine tumors. METHODS: A retrospective study was conducted on data from patients with diagnosis of neuroendocrine tumor originated from pancreas (pNET) or gastrointestinal tract (stomach, appendix, and ileus; GI-NET) made between January 2003 and December 2004 and followed up at our institution. Archival material should be available for revision according to WHO 2010 neuroendocrine tumor classification and for p-mTOR, SSTR2A, and IGF-1R immunostaining, calculating a quantitative score (QS). We evaluated clinical, pathological, and immunohistochemistry features for association with the presence of advanced disease at diagnosis and disease relapse in patients who have undergone radical surgery. RESULTS: Archival material from 64 patients was analyzed (37 pNETs and 27 GI-NETs). In these patients, G2 grading, low SSTR2A QS, and high p-mTOR QS were associated with advanced disease at diagnosis at multivariate analysis. Risk of recurrence in 49 patients with R0-resected tumors was higher for G2 grading, stage IIIB-IV, low IGF-1R QS, and high p-mTOR QS at univariate analysis. CONCLUSIONS: With the limits of retrospective data, activation of m-TOR is correlated with advanced disease at diagnosis and with shorter disease-free survival after R0 resection. Validation through prospective studies is needed.

9.
Radiat Prot Dosimetry ; 137(3-4): 288-93, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19864329

RESUMO

The cement industry of this work is located in the Fumane valley, in the north of Verona. The environmental impact of the air emissions from the plant was studied using different methods: the characterisation of the raw materials utilised in the production process and of the emissions from the chimney of the clinker kiln; the sampling of the air particles on filter in the region around the plant; the biomonitoring using transplanted mosses; the study of the air pollution dispersion using a model.


Assuntos
Bioensaio/métodos , Carga Corporal (Radioterapia) , Materiais de Construção/análise , Monitoramento Ambiental/métodos , Resíduos Industriais/análise , Material Particulado/análise , População Rural , Itália , Tamanho da Partícula
10.
Lipids ; 27(12): 1005-12, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1487948

RESUMO

The plasma kinetics of a preparation of dilinoleoyl phosphatidylcholine (DLPC) specifically labeled with 3H in the choline moiety and with 14C in the 2-fatty acid (FA) were evaluated in six healthy volunteers after oral administration. Retention of both isotopes in plasma exceeded expectations, with a half-life in the elimination phase of 172.2 h for 3H and 69.7 h for 14C. Up to 60 d after administration, there were still significant levels of radioactivity present in plasma. The relative stability of the [14C]FA label was demonstrated by the retention for more than 12 h of an isotope ratio close to that of the compound administered. The 14C label of DLPC remained in position-2, as assessed by cleavage of plasma phospholipids with phospholipase A2. The [3H]choline label showed an early incorporation into high density lipoproteins and subsequently into low density lipoproteins (LDL); conversely, the 14C radioactivity was rapidly incorporated into triacylglycerols that were mainly associated with very low density lipoproteins. Radioactivity measurements revealed that both isotopes remained the longest time in LDL. In red blood cell (RBC) lipids, [3H]choline radioactivity accumulated over time, with a plateau after 48 h, whereas FA radioactivity accumulated more rapidly and was followed by a progressive decay. Analysis of the isotope ratio in these cells suggested an early incorporation of lyso products followed by rapid transfer of FA from plasma. The RBC maintained considerable radioactivity for a prolonged time, thus acting as a possible reservoir for the DLPC administered.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Eritrócitos/metabolismo , Fosfatidilcolinas/farmacocinética , Plasma/metabolismo , Administração Oral , Adulto , Colina/sangue , Colina/farmacocinética , Feminino , Humanos , Marcação por Isótopo , Ácidos Linolênicos/sangue , Ácidos Linolênicos/farmacocinética , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , Fosfolipases A/metabolismo , Fosfolipases A2
11.
Artif Organs ; 16(6): 625-9, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1482334

RESUMO

Levels of plasma lipids and the fatty acid composition of major plasma lipid classes have been determined in chronically uremic patients before and after treatments with hemofiltration, high efficiency paired filtration dialysis, or acetate-free biofiltration. The major findings are a decrease of triglycerides and an increase of total free fatty acids (FFAs) at the end of the dialytic session--already reported in the literature--that do not appear to be strictly dependent on heparin administration. The changes in the plasma concentrations of selected saturated and polyunsaturated fatty acids, which may contribute to alteration of functional parameters in the cardiovascular system in dialyzed patients, are different in the various types of techniques.


Assuntos
Ácidos Graxos não Esterificados/sangue , Hemofiltração , Lipídeos/sangue , Diálise Renal , Uremia/sangue , Uremia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
12.
Lipids ; 27(8): 624-8, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1406073

RESUMO

Four diets containing 20% of energy (en%) as fat and with linoleic acid contents of 1.9, 3.1, 7.7 and 10.1 en%, respectively, were fed to one-month-old male rats for three months. The fatty acid profiles and the levels of the major n-6 and n-3 fatty acids in the lipids of plasma, liver, heart and kidney were measured. We found that with increasing concentrations of 18:2n-6 in the diet, linoleic acid rose in plasma and in all organs, but long-chain n-6 and n-3 fatty acids responded differently. In liver, arachidonic acid increased and n-3 fatty acids were not significantly affected; in heart, both arachidonic and docosahexaenoic acids were progressively reduced; and in kidney, there was no change of n-6 and n-3. The results indicate that incremental changes in dietary linoleate affect the levels of polyunsaturated fatty acids in liver and extrahepatic organs differently.


Assuntos
Ácido Araquidônico/metabolismo , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos/metabolismo , Ácidos Linoleicos/farmacologia , Fígado/metabolismo , Miocárdio/metabolismo , Animais , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos/sangue , Rim/metabolismo , Ácido Linoleico , Ácidos Linoleicos/administração & dosagem , Metabolismo dos Lipídeos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Masculino , Especificidade de Órgãos , Ratos
13.
J Pediatr ; 119(4): 562-7, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1919887

RESUMO

The fatty acid composition of plasma and erythrocyte lipids was analyzed in 15 children with phenylketonuria (aged 3 to 12 years) during dietary treatment aimed to maintain plasma phenylalanine levels at less than 8 mg/dl (485 mumol/L), and compared with those of 12 matched control subjects. The diet of children with phenylketonuria provided less protein, with a very low proportion of animal proteins, less fat, but a higher proportion of linoleic acid as a percentage of calories, and a higher carbohydrate content versus that in the diet of control subjects. The children with phenylketonuria had higher plasma levels of oleic acid but lower levels of arachidonic (n-6) and n-3 fatty acids. Linoleic and eicosatrienoic (n-9) acid levels were the same in both groups. These changes in patients with phenylketonuria resemble those observed in vegetarians and may be due to the absence of preformed arachidonic acid and long-chain n-3 fatty acids in the phenylketonuric diet.


Assuntos
Ácidos Graxos Insaturados/sangue , Fenilcetonúrias/sangue , Criança , Pré-Escolar , Colesterol/sangue , Dieta , Ingestão de Energia , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Humanos , Masculino , Fenilcetonúrias/dietoterapia
14.
Eur J Pharmacol ; 202(3): 311-6, 1991 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-1721028

RESUMO

We studied the aggregation of collagen and ADP-stimulated platelet-rich plasma (PRP) and the formation of thromboxane B2 (TxB2) by collagen-stimulated PRP in spontaneously hypertensive rats (SHR) and in Wistar-Kyoto control rats (WKY). In addition, we evaluated the inhibition of the aggregation of PRP following homologous or heterologous perfusions through isolated aortas, the release of 6-keto-prostaglandin (PG)F1 alpha from these arteries perfused with PRP, and the sensitivity of PRP to the antiaggregatory activity of the stable PGI2 analogue, iloprost, in both SHR and WKY. The lower activities (aggregation induced by ADP and collagen, collagen-stimulated TxB2 production) of SHR platelets, were not accompanied by morphological differences from WKY platelets. These changes were associated with a greater release of arterial 6-keto-PGF1 alpha, with greater platelet antiaggregatory activity of the arterial wall and with higher sensitivity of platelets to iloprost. The lower reactivity of platelets to aggregating agents, and the greater sensitivity to prostacyclin, associated with a greater production of arterial prostacyclin were the major changes observed in SHR animals. These alterations in the SHR vs. normotensive WKY may lead to an enhanced risk of hemorrhage in the hypertensive state.


Assuntos
6-Cetoprostaglandina F1 alfa/sangue , Plaquetas/metabolismo , Hipertensão/sangue , Tromboxano B2/sangue , Difosfato de Adenosina/farmacologia , Animais , Aorta , Plaquetas/ultraestrutura , Colágeno/farmacologia , Iloprosta/farmacologia , Masculino , Perfusão , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
16.
J Nutr Biochem ; 1(11): 565-71, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15539175

RESUMO

We have studied the effects of semisynthetic diets containing 5% by weight (12% of the energy) of either olive oil (70% oleic acid, OA) or corn oil (58% linoleic acid), or fish oil (Max EPA, containing about 30% eicosapentaenoic, EPA C 20:5 n-3, plus docosahexaenoic, DHA C 22:6 n-3, acids, and less than 2% linoleic acid), fed to male rabbits for a period of five weeks, on plasma and platelet fatty acids and platelet thromboxane formation. Aim of the study was to quantitate the absolute changes of n-6 and n-3 fatty acid levels in plasma and platelet lipid pools after dietary manipulations and to correlate the effects on eicosanoid-precursor fatty acids with those on platelet thromboxane formation. The major differences were found when comparing the group fed fish oil and depleted linoleic acid vs the other groups. The accumulation of n-3 fatty acids in various lipid classes was associated with modifications in the distribution of linoleic acid and arachidonic acid in different lipid pools. In platelets maximal incorporation of n-3 fatty acids occurred in phosphatidyl ethanolamine, which also participated in most of the total arachidonic acid reduction occurring in platelets, and linoleic acid, more than archidonic acid, was replaced by n-3 fatty acids in various phospholipids. The archidonic acid content of phosphatidyl choline was unaffected and that of phosphatidyl inositol only marginally reduced. Thromboxane formation by thrombin stimulated platelets did not differ among the three groups, and this may be related to the minimal changes of arachidonic acid in phosphatidyl choline and phosphatidyl inositol.

17.
Biochem Pharmacol ; 39(1): 129-33, 1990 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-2105092

RESUMO

We have studied the effects of semi-synthetic diets rich in either n-9 (olive oil, OO) or n-6 (corn oil, CO), or n-3 (fish oil, FO, as MaxEPA) fatty acids on the levels of major PUFA in platelet lipids, on the generation of inositol phosphates by [3H]inositol labelled platelets after stimulation with thrombin and of thromboxane B2 (TxB2) by platelet rich plasma (PRP) after stimulation with collagen. The predicted elevations of oleic (OA), linoleic (LA) and eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were observed in platelet lipids of each animal group, but in the MaxEPA fed group accumulation of EPA was associated with depletion of linoleic acid (LA) rather than of arachidonic acid (AA). Basal levels of inositol-tris-phosphate (IP3) in platelets were lowest in the OO group and highest in the CO group, whereas the increment after thrombin stimulation (1 unit/ml NIH) was maximal in the OO group and minimal in the FO group. Instead, when generation of TxB2 by stimulated platelets was evaluated, no appreciable difference among the various groups could be detected, in accordance with the limited modifications of platelet AA content induced by the diets. The overall data indicate that dietary fatty acids modulate the pathway of inositol phosphate generation in rabbit platelets, independently of modifications of TxB2 production.


Assuntos
Plaquetas/metabolismo , Gorduras na Dieta/farmacologia , Ácidos Graxos/farmacologia , Fosfatos de Inositol/sangue , Tromboxano B2/sangue , Animais , Ácido Araquidônico , Ácidos Araquidônicos/sangue , Plaquetas/efeitos dos fármacos , Óleo de Milho/farmacologia , Gorduras na Dieta/administração & dosagem , Ácido Eicosapentaenoico/sangue , Ácidos Graxos/administração & dosagem , Óleos de Peixe/farmacologia , Cinética , Ácido Linoleico , Ácidos Linoleicos/sangue , Masculino , Azeite de Oliva , Óleos de Plantas/farmacologia , Coelhos , Trombina/farmacologia
18.
JPEN J Parenter Enteral Nutr ; 13(5): 501-4, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2607591

RESUMO

The fatty acids profiles of plasma and red blood cell lipids have been evaluated in 12 malnourished cancer patients in comparison with samples from eight healthy controls. In such patients, significantly lower levels of linoleic acid (LA) as percentage of total fatty acids were observed in plasma phospholipids (PL) and cholesterol esters (CE), and in red blood cells PL. The levels of arachidonic acid (AA) and the unsaturation index of the two lipid classes were also reduced in plasma CE but not in PL. In spite of the marked reduction of LA and, more generally, of total polyunsaturated fatty acids (PUFA), no elevation of eicosatrienoic acid (20:3 n-9) was observed, such acid being considered a typical index of essential fatty deficiency. Moreover, no modification of the parameters indicating impairment of the fatty acid desaturation activity was shown. In addition, the levels of palmitic and oleic acids were significantly higher in both plasma PL and CE and in red blood cells PL. The reported elevation of the oleic to stearic acid ratio in lipids of red blood cells from malnourished cancer patients, already observed by other authors, was confirmed in our study. This ratio was even more markedly elevated in plasma lipids of the patients. A very good correlation was found between the reduction of linoleic acid levels, especially in plasma CE, and weight loss, suggesting enhanced utilization of this fatty acid in association with extensive depletion of lipid stores, in this pathological state.


Assuntos
Eritrócitos/metabolismo , Ácidos Graxos Insaturados/sangue , Lipídeos/sangue , Neoplasias/sangue , Distúrbios Nutricionais/sangue , Ácidos Oleicos/sangue , Ácidos Esteáricos/sangue , Feminino , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Distúrbios Nutricionais/etiologia , Fosfolipídeos/sangue
19.
Wien Klin Wochenschr ; 101(8): 267-71, 1989 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-2658330

RESUMO

Dietary fatty acids of the n-6 mainly linoleic acid (LA) series, and of the n-3, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) series both reduce plasma cholesterol levels and platelet responses to aggregating agents. The potency of n-3 fatty acids, which are present in relatively high concentrations in fish oils, is at least one order of magnitude greater than that of LA. The effects of fish oils appear to be related to the incorporation of EPA into plasma lipoproteins and cell phospholipid pools, thus modulating metabolic processes within specific lipid pools. Inhibition of platelet function and modifications of the activity of other blood cells, such as leukocytes, is attributed to interference with the eicosanoid system. Competition of EPA with arachidonic acid (AA) for the oxygenases and/or generation of less active metabolites from this precursor are the major mechanisms of action. Feeding studies in experimental animals indicate that exogenously administered n-3 fatty acids undergo distribution among the major plasma lipid classes and platelet phospholipids quite different to that of endogenous AA. In addition, the generation of inositolphosphates by stimulated platelets is decreased by dietary n-3 fatty acids in a manner independent of the effects on the eicosanoid system. It appears that polyunsaturated fatty acids (PUFA) of the n-6 and n-3 series are differently handled in various lipid pools and that early steps of cell activation, in addition to the generation of eicosanoids, are affected by dietary fatty acids. This indicates that fatty acids modulate key steps in the regulation of cell function and biochemistry.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arteriosclerose/prevenção & controle , Plaquetas/fisiologia , Ácidos Graxos Insaturados/administração & dosagem , Hipercolesterolemia/prevenção & controle , Lipídeos/sangue , Agregação Plaquetária , Arteriosclerose/sangue , Humanos , Hipercolesterolemia/sangue
20.
Atherosclerosis ; 74(1-2): 169-77, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3214476

RESUMO

The Ivanovas-Sieve (IVA-SIV) rat represents the only available animal model of endogenous hypertriglyceridemia, in the absence of obesity and/or overt diabetes. Since plasma lipids/lipoproteins can modulate platelet reactivity and eicosanoid metabolism, these were examined in two groups of Charles River (CR) and IVA-SIV rats of identical age. The IVA-SIV rats had 2-fold higher plasma triglycerides and a 55% higher number of circulating platelets; the number of platelets was significantly correlated with triglyceridemia. Platelet reactivity to ADP and to collagen was significantly reduced in these animals, whereas the formation of thromboxane B2 did not differ from that of the CR. After perfusion of platelet-rich plasma (PRP) through the aortas of animals of the two strains, platelet aggregability, already lower in the IVA-SIV, was reduced to a higher extent compared to the CR. Increased levels of the prostacyclin metabolite 6-keto-PGF1 alpha were identified in the perfusate from the aortas of IVA-SIV rats. Platelets from these animals also showed an increased sensitivity to Iloprost, a stable prostacyclin analogue, with an IC50 1.7-fold lower compared to CR rats. Spontaneous hypertriglyceridemia in the IVA-SIV model is not associated with platelet hyperresponsiveness, but rather with a reduced sensitivity to major aggregants.


Assuntos
6-Cetoprostaglandina F1 alfa/sangue , Hipertrigliceridemia/sangue , Agregação Plaquetária , Tromboxano B2/sangue , Animais , Aorta Torácica , Masculino , Perfusão , Contagem de Plaquetas , Ratos , Ratos Endogâmicos , Triglicerídeos/sangue
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