Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Más filtros

Banco de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Ann Chir Plast Esthet ; 68(2): 113-122, 2023 Apr.
Artículo en Francés | MEDLINE | ID: mdl-36670044

RESUMEN

PURPOSE: The aim of this study was to analyze the predictability of virtual surgical planning of mandibular reconstruction by osteogenic distraction (OD) with a custom-made osteogenic distraction device (DEOS) after ballistic trauma and to make recommendations to mitigate potential sources of discrepancy. METHODS: This retrospective study involved 12 patients who were victims of facial mandibular ballistic trauma and were reconstructed with osteogenic distraction with a DEOS device. Postoperative images were compared to the planned situation by means of several measures made in two plans : distraction plane and frontal plane. RESULTS: The mean bone loss was 54.2mm. The anteroposterior difference was systematically inferior or equal postoperatively (10.8mm). The interrami angle difference in the frontal plane was positive, with an average of 4.8°. There was a significant negative correlation in univariate analysis between the antero-posterior difference measurement and the difference of the interrami angle in distraction. CONCLUSION: A significant difference between the planning and postoperative results was shown, explained by the device being too adjustable leading to the loosening of the locking screws of the device. A static analysis showed that there are significant rotational forces at the carriages, which can lead to the loosening of the locking elements. It is then proposed that the device be optimized by customization of some elements.


Asunto(s)
Traumatismos Faciales , Reconstrucción Mandibular , Osteogénesis por Distracción , Humanos , Estudios Retrospectivos , Mandíbula/cirugía , Reconstrucción Mandibular/métodos , Osteogénesis por Distracción/métodos
2.
Mar Environ Res ; 199: 106614, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38905868

RESUMEN

Marine aggregate extraction represents an opportunity to face the depletion of terrestrial aggregate resources. The environmental effects of this activity have been assessed in several studies, leading to the formulation of recommendations to mitigate its effects. This study investigates its environmental impacts in a coarse, high-current environment with low-intensity extraction, a unique scenario not extensively studied before. Employing multivariate analyses and a trophic group approach, it examines complex responses at both species and community levels. Results indicate a decline in biodiversity, promoting the establishment of r-selected species, particularly filter feeders. Although site restoration timelines remain uncertain, initial indications suggest rapid recovery (2-3 years) for this site. The study also discusses methodological challenges in sampling these low-intensity dredged sites and emphasizes the need for new indices tailored to this pressure and coarse sediments under strong hydrodynamics. These insights offer valuable directions for future research.

3.
Mar Pollut Bull ; 200: 116042, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244358

RESUMEN

This study addresses the scarcity of evidence on the relationship between benthic communities and coarse-grained sediments in the eastern English Channel. The region's geological history contributes to its predominantly coarse sediment composition. The study employs ternary plots to visualize benthic species' preferences and tolerance for sediment types, revealing their effectiveness. Redundancy Analyses (RDA) and species-level quantile regressions explore the influence of grain size on benthic species distribution. The results indicate a moderate impact of grain size, influenced by hydrodynamics. Estuaries, particularly the Seine Estuary, significantly shape benthic species distribution. Quantile regressions underscore the varied responses of benthic communities along the grain size gradient. The study underscores the importance of considering coarse sediments, offering insights into the complex relationship between benthic communities and sediment characteristics.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Sedimentos Geológicos/química , Monitoreo del Ambiente/métodos , Estuarios , Ecosistema
4.
J Stomatol Oral Maxillofac Surg ; 124(2): 101288, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36096396

RESUMEN

OBJECTIVE: In bilateral cleft lip cases, surgeons have long known that the medial nasal prominence or prolabium is devoid of muscle. Despite cheiloplasty restoring orbicular muscle continuity, moustache hair growth is less developed on the philtral skin. We sought to understand this hair disparity. BASIC PROCEDURES: The authors conducted a comprehensive literature search using reference materials on the physiological and pathological development of the face in utero and the PubMed database using the keywords 'embryology', 'bilateral cleft lip' and 'hair'. MAIN RESULTS: In bilateral cleft lip, the normal fusion between the maxillary and intermaxillary process does not occur, and the migration of cranial neural crest cells (CNCC) is disturbed. CNCCs from different locations and with different myoblastic differentiation potential are arrested on each side of the cleft. Therefore, a reduced concentration of myoblasts and myocytes as well as hormone receptors in the medial process could hinders the normal physiological development of the different layers of the philtral skin and especially the skin appendages. CONCLUSION: Philtral hair sparsity in patients with bilateral cleft lip can be explain by a defect in the migration of CNCCs to the prolabium, whose cells are not able to develop hair follicles, due to a disruption of the exchange of Wnt/ß-catenin, EDA, and or Noggin signals and due to the absence of androgen receptor.


Asunto(s)
Labio Leporino , Procedimientos de Cirugía Plástica , Humanos , Labio Leporino/diagnóstico , Labio Leporino/cirugía , Labio/anomalías , Labio/patología , Labio/cirugía , Cabello
5.
J Stomatol Oral Maxillofac Surg ; 123(5): e614-e618, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35093587

RESUMEN

OBJECTIVES: The objective of this study was to evaluate the efficiency of three methods of isolated mandibular fracture intraoperative reduction. MATERIALS AND METHODS: This 6-year retrospective study included patients with isolated extra-articular mandibular fractures who would benefit from osteosynthesis. The endpoint was postoperative occlusion according to the type of intraoperative immobilization: screws, arch, or manual reduction. RESULTS: A total of 145 patients were included, with 233 fractures. Forty-five patients underwent manual reduction without maxillo-mandibular fixation (MMF), 51 MMF with screws, and 49 MMF with arch, with 11.1%, 5.9% and 4.1% of patients in these groups experiencing postoperative malocclusion, respectively. The overall malocclusion rate was 6.9%. There was no significant difference among the 3 methods according to univariate statistical analysis (p = 0.42) or after comparing MMF (grouping screws and arches) to manual reduction without MMF (p = 0.29). CONCLUSION: This study did not show a significant difference between the different methods of intraoperative reduction of isolated extra-articular mandibular fractures, even though intraoperative MMF was much more commonly used for complex fractures. However, there is a non-significant tendency to get a better post-operative occlusal result with MMF, which remains the reference traitement. Intraoperative manual reduction without MMF may be used within trained teams in some instances.


Asunto(s)
Maloclusión , Fracturas Mandibulares , Fijación Interna de Fracturas/métodos , Humanos , Técnicas de Fijación de Maxilares , Fracturas Mandibulares/cirugía , Estudios Retrospectivos
6.
J Stomatol Oral Maxillofac Surg ; 123(5): 581-586, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34995819

RESUMEN

The main objective of this study was to evaluate long-term stability of rigid osteosynthesis in the context of advancement genioplasty. Bone stability was defined as a long-term bone loss of less than 2 mm. Measurements were performed on lateral cephalograms, in the sagittal and vertical planes, at three times: preoperative (T0, less than one month before surgery), early postoperative (T1, at least one month post-operatively) and late postoperative (T2, at least one year after surgery). 25 patients were included in the study, with a mean follow-up of 3.47 years (range 1-9.42 years). The mean sagittal bone advancement at T1 was 4.06 mm ± 1.34, with a bone loss of 0.65 mm at T2 (p = 0.001). The mean vertical bone movement was 1.25 mm ± 0.47 at T1, with a relapse at T2 of 0.34 mm (p = 0.27). The soft-to-hard tissue ratio was 78% in the sagittal plane. Rigid osteosynthesis offers long-term stability, with very little change in clinical outcome, in advanced genioplasty.


Asunto(s)
Mentoplastia , Avance Mandibular , Cefalometría , Fijación Interna de Fracturas , Humanos , Estudios Retrospectivos
7.
Biochimie ; 179: 275-280, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32920170

RESUMEN

In around 10% of SARS-CoV-2 infected patients, coronavirus disease-2019 (Covid-19) symptoms are complicated with a severe lung damage called Acute Respiratory Distress Syndrome (ARDS), which is often lethal. ARDS is mainly associated with an uncontrolled overproduction of immune cells and cytokines, called "cytokine storm syndrome"; it appears 7-15 days following the onset of symptoms, leading to systemic inflammation and multiple organ failure. Because they are well-known metabolic precursors of specialized pro-resolving lipid mediators (SPMs), omega-3 long-chain polyunsaturated fatty acids (omega-3 LC-PUFAs) could help improve the resolution of the inflammatory balance, limiting therefore the level and duration of the critical inflammatory period. Omega-3 LC-PUFAs may also interact at different stages of the viral infection, notably on the virus entry and replication. In the absence of demonstrated treatment and while waiting for vaccine possibility, the use of omega-3 LC-PUFAs deserve therefore to be considered, based on previous clinical studies suggesting that omega-3 supplementation could improve clinical outcomes of critically ill patients at the acute phase of ARDS. In this context, it is crucial to remind that the omega-3 PUFA dietary intake levels in Western countries remains largely below the current recommendations, considering both the omega-3 precursor α-linolenic acid (ALA) and long chain derivatives such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). An optimized omega-3 PUFAs status could be helpful to prevent infectious diseases, including Covid-19.


Asunto(s)
COVID-19/complicaciones , Suplementos Dietéticos , Ácidos Grasos Omega-3/farmacología , Animales , Ensayos Clínicos como Asunto , Humanos
8.
Prog Lipid Res ; 45(3): 203-36, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16516300

RESUMEN

The importance of a high fat intake in the increasing prevalence of childhood and adult obesity remains controversial. Moreover, qualitative changes (i.e. the fatty acid composition of fats) have been largely disregarded. Herein is reviewed the role of polyunsaturated fatty acids (PUFAs) of the n-6 series in promoting adipogenesis in vitro and favouring adipose tissue development in rodents during the gestation/suckling period. Epidemiological data from infant studies as well as the assessment of the fatty acid composition of mature breast milk and infant formulas over the last decades in the Western industrialized world are revisited and appear consistent with animal data. Changes over decades in the intake of n-6 and n-3 PUFAs, with a striking increase in the linoleic acid/alpha-linolenic ratio, are observed. In adults, using a consumption model based upon production data, similar changes in the PUFA content of ingested lipids have been found for France, and are associated with an increase of fat consumption over the last 40 years. These profound quantitative and qualitative alterations can be traced in the food chain and shown to be due to changes in human dietary habits as well as in the feeding pattern of breeding stock. If prevention of obesity is a key issue for future generations, agricultural and food industry policies should be thoroughly reevaluated.


Asunto(s)
Tejido Adiposo/crecimiento & desarrollo , Ácidos Grasos Omega-6/administración & dosificación , Obesidad/etiología , Adipogénesis/fisiología , Adulto , Animales , Grasas de la Dieta/administración & dosificación , Ácidos Grasos Omega-3/administración & dosificación , Conducta Alimentaria , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Leche Humana/química , Obesidad/fisiopatología
9.
Isr Med Assoc J ; 10(4): 262-5, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18548978

RESUMEN

BACKGROUND: As high dietary n-6 polyunsaturated fatty acids and n-6:n-3 PUFA ratio may contribute to many western ailments, increasing n-3 PUFA in foods could be beneficial. The nutritional significance of n-3 PUFA-fortified egg vs. enzymatically competitive high n-6 PUFA diets is debatable. OBJECTIVES: To evaluate the dietary contribution of 'field fortification' of eggs by adding n-3 PUFA to high n-6 PUFA hen feed and to assess whether it meets consumer preferences. METHODS: Laying hens (n=3500) were fed n-3 PUFA-fortified (5% extruded linseed) feed or standard (control) feed for 5 weeks. Nutritional significance was evaluated for western (American, Israeli) populations. RESULTS: Compared to regular (control) eggs, fortified eggs yielded a 3.8-fold increase in total n-3 PUFA, 6.4-fold alpha-linolenic acid (18:3), and 2.4-fold docohexaenoic acid 22:6). N-6:n-3 PUFA ratio decreased 3.6-fold, and n-6:n-3 long chain PUFA ratio (AA:DHA) 3.0-fold (P< 0.0003). Sensory evaluations were not significantly different. Egg cost increased by 1.5-3.0%. Fortified egg n-3 PUFA content averaged 14.3% of the current intake of Americans and 15.9% of Israelis - 9.8 and 10.6% of upper Dietary Reference Intakes, respectively. Egg DHA content averaged 33.7 and 41.4% of upper DRI. Current cholesterol intakes average 281 and 263 mg/day (median 214 and 184 mg/day) including 0.7 and 0.5 egg/day; reported hypercholesterolemia rates are 17.7 and 16.5%, respectively. CONCLUSIONS: Effective concentration and transformation of supplemental n-3 PUFA/LCPUFA from feed to egg substantially enhanced egg n-3 PUFA %DRI, particularly of DHA, critical for health but often deficient. Such land-based n-3 PUFA/LCPUFA fortification may be applicable to high n-6 PUFA diets, fitting within cholesterol limitations and market criteria. It may contribute to general health and specific requirements (i.e., pregnancy and lactation), with possibilities of wide accessibility and standardization.


Asunto(s)
Alimentación Animal , Comportamiento del Consumidor , Huevos/análisis , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6/análisis , Alimentos Fortificados , Animales , Pollos , Costos y Análisis de Costo , Huevos/economía , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Femenino , Humanos , Masculino , Valor Nutritivo
10.
Lipids ; 39(4): 325-34, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15357020

RESUMEN

If an increased consumption of alpha-linolenic acid (ALA) is to be promoted in parallel with that of n-3 long-chain-rich food, it is necessary to consider to what extent dietary ALA can be absorbed, transported, stored, and converted into long-chain derivatives. We investigated these processes in male hamsters, over a broad range of supply as linseed oil (0.37, 3.5, 6.9, and 14.6% energy). Linoleic acid (LA) was kept constant (8.5% energy), and the LA/ALA ratio was varied from 22.5 to 0.6. The apparent absorption of individual FA was very high (>96%), and that of ALA remained almost maximum even at the largest supply (99.5%). The capacity for ALA transport and storage had no limitation over the chosen range of dietary intake. Indeed, ALA intake was significantly correlated with ALA level not only in cholesteryl esters (from 0.3 to 9.7% of total FA) but also in plasma phospholipids and red blood cells (RBC), which makes blood components extremely reliable as biomarkers of ALA consumption. Similarly, ALA storage in adipose tissue increased from 0.85 to 14% of total FA and was highly correlated with ALA intake. As for bioconversion, dietary ALA failed to increase 22:6n-3, decreased 20:4n-6, and efficiently increased 20:5n-3 (EPA) in RBC and cardiomyocytes. EPA accumulation did not tend to plateau, in accordance with identical activities of delta5- and delta6-desaturases in all groups. Dietary supply of ALA was therefore a very efficient means of improving the 20:4n-6 to 20:5n-3 balance.


Asunto(s)
Grasas Insaturadas en la Dieta/metabolismo , Ácidos Grasos Insaturados/metabolismo , Mesocricetus/metabolismo , Ácido alfa-Linolénico/administración & dosificación , Tejido Adiposo/química , Animales , Peso Corporal , Cricetinae , Ácidos Grasos Insaturados/administración & dosificación , Humanos , Metabolismo de los Lípidos , Masculino , Miocardio/química , Ácido alfa-Linolénico/metabolismo
11.
J Agric Food Chem ; 57(6): 2249-54, 2009 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-19243170

RESUMEN

Farmed fish high in n-6 PUFA may undermine fish nutritional expectations and intake recommendations for n-3 PUFA requirements and exacerbate rather than improve already high n-6/n-3 PUFA diets. Dietary contribution of fish fortification by linseed-based n-3 PUFA was evaluated. Mango tilapia (12 months old) with high n-6 PUFA (21.8 FA%, n-6/n-3 ratio 4.6:1) were fed standard/control (T(C)) or linseed-supplemented (5%, T(5%); 7%, T(7%)) feed for 61 days regular-growth and 120 days stock-growth (to 650 g). Compared to T(C), n-3 PUFA increased in T(5%) 46% and T(7%) 58%; ALA in T(5%) increased 100% and T(7%) 167%; EPA+DHA in T(5%) increased 14% and T(7%) 23% (p < 0.05); n-6 PUFA/LCPUFA were unchanged. T(7%) EPA+DHA 168 mg/100 g of raw fillet is comparable to current American intake and Dietary Reference Intakes; controlled cooking preserved approximately 90% EPA+DHA. n-6/n-3 ratios decreased 16-38% in total PUFA to 2.3:1 and in LCPUFA to 0.61:1. Linseed supplementation could improve tilapia n-3 PUFA/LCPUFA, ameliorating n-3 PUFA scarcity and unexpectedly high fish n-6 PUFA content, potentially making a significant nutritional contribution.


Asunto(s)
Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/análisis , Lino , Alimentos Fortificados , Carne/análisis , Tilapia , Animales , Dieta , Valor Nutritivo , Semillas
12.
Nutr Metab (Lond) ; 6: 14, 2009 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-19320987

RESUMEN

BACKGROUND: Previous work showed that the functional cardiac effect of dietary alpha-linolenic acid (ALA) in rats requires a long feeding period (6 months), although a docosahexaenoic (DHA) acid-supply affects cardiac adrenergic response after 2 months. However, the total cardiac membrane n-3 polyunsaturated fatty acid (PUFA) composition remained unchanged after 2 months. This delay could be due to a specific reorganization of the different subcellular membrane PUFA profiles. This study was designed to investigate the evolution between 2 and 6 months of diet duration of the fatty acid profile in sarcolemmal (SL), mitochondrial (MI), nuclear (NU) and sarcoplasmic reticulum (SR) membrane fractions. METHODS: Male Wistar rats were randomly assigned to 3 dietary groups (n = 10/diet/period), either n-3 PUFA-free diet (CTL), or ALA or DHA-rich diets. After 2 or 6 months, the subcellular cardiac membrane fractions were separated by differential centrifugations and sucrose gradients. Each membrane profile was analysed by gas chromatography (GC) after lipid extraction. RESULTS: As expected the n-3 PUFA-rich diets incorporated n-3 PUFA instead of n-6 PUFA in all the subcellular fractions, which also exhibited individual specificities. The diet duration increased SFA and decreased PUFA in SL, whereas NU remained constant. The SR and MI enriched in n-3 PUFA exhibited a decreased DHA level with ageing in the DHA and CTL groups. Conversely, the n-3 PUFA level remained unchanged in the ALA group, due to a significant increase in docosapentaenoic acid (DPA). N-3 PUFA rich diets lead to a better PUFA profile in all the fractions and significantly prevent the profile modifications induced by ageing. CONCLUSION: With the ALA diet the n-3 PUFA content, particularly in SR and SL kept increasing between 2 and 6 months, which may partly account for the delay to achieve the modification of adrenergic response.

13.
Am J Physiol Heart Circ Physiol ; 293(4): H2296-304, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17526653

RESUMEN

The present study was designed to evaluate whether long-term intake of dietary alpha-linolenic acid (ALA), supplied as whole grain-extruded linseed, can increase endogenous production of n-3 long-chain polyunsaturated fatty acids (FAs) in healthy adult rats and influence the heart rate (HR) and adrenergic response in the same way as docosahexaenoic acid (DHA)-rich diets. DHA enrichment was evaluated using FA analysis of tissue phospholipids after 8, 16, 24, and 32 wk of feeding in male Wistar rats randomly assigned to three dietary groups (n = 8 in each group): a reference fat diet (RFD), an ALA-rich (ALA) diet, and a DHA-rich (DHA) diet. At 1 wk before the animals were killed, under anesthesia, HR was measured from ECG recordings during an adrenergic stimulation challenge (n = 8). There was a significant increase of DHA in the cardiac membrane in the ALA group compared with the RFD group. DHA content in the cardiac membrane was approximately 10% in the ALA group vs. 20% in the DHA group and 4% in the RFD group. The cardiac FA profile was established after 2 mo and remained essentially unchanged thereafter. Regardless of the diet, DHA in the heart decreased with age. Nevertheless, DHA content in the heart remained at >15% in the DHA group and remained greater in older rats fed the ALA diet than in younger RFD-fed rats. Basal HR decreased in the ALA group (395 +/- 24.9 beats/min) to a level between that of the DHA and RFD groups (375 +/- 26.4 and 407 +/- 36.7 beats/min, respectively). Both n-3 dietary intakes contribute to enhancement of the chronotropic response to adrenergic agonist stimulation. Regulation of HR by neurohumoral mediators may be controlled by lower content of DHA, e.g., by a dietary supply of extruded linseed (ALA).


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Membrana Celular/efectos de los fármacos , Grasas de la Dieta/farmacología , Ácidos Docosahexaenoicos/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Corazón/efectos de los fármacos , Isoproterenol/farmacología , Ácido alfa-Linolénico/farmacología , Animales , Peso Corporal/efectos de los fármacos , Membrana Celular/metabolismo , Grasas de la Dieta/sangre , Grasas de la Dieta/metabolismo , Ácidos Docosahexaenoicos/sangre , Ácidos Docosahexaenoicos/metabolismo , Electrocardiografía , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Factores de Tiempo , Ácido alfa-Linolénico/sangre , Ácido alfa-Linolénico/metabolismo
15.
Br J Nutr ; 95(4): 709-20, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16571150

RESUMEN

Gender and dietary fatty acids are involved in the regulation of lipid metabolism, disturbances of which can lead to pathologies such as metabolic syndrome or CVD. Possible interactions between these factors were investigated in male and female hamsters fed diets rich in either saturated fatty acids ( "butter" diet) or in alpha-linolenic acid ( "linseed oil" diet). Gender effect predominated over the diet effect on cholesterol (CH) metabolism; compared to males, females exhibited lower concentrations of plasma total CH (-20 %, P<0.001), LDL-CH (-40 %, P<0.001) and HDL-CH (-16 %, P<0.001), together with higher LDL receptor (+40 %) and lower HDL receptor (-60 %) hepatic content. Triacylglycerol (TG) metabolism was affected by diet above all: compared to animals fed the "butter" diet, those fed the "linseed oil" diet exhibited lower plasma (-23 %, P=0.046) and liver TG (-20 %, P=0.026) concentration which may result from both an increased beta-oxidation (P<0.001), without any change in PPARalpha mRNA, and a decreased hepatic lipogenesis (P=0.023), without increased sterol response element binding protein 1c (SREBP1c) mRNA. The response to diet was much more pronounced in males than in females, without gender effect on the transcription level of PPARalpha and SREBP1c. Finally, the "linseed oil" diet decreased the insulin resistance index (-80 %, P<0.001) with a more marked effect in males, in relation to their higher hepatic PPARgamma expression (+90 %, P=0.012). In conclusion, in our model, the response of either TG or CH to dietary fatty acids is modulated differently by gender. The possible relevance of these interactions to dietary practice should be taken into account in man.


Asunto(s)
Grasas de la Dieta/metabolismo , Metabolismo de los Lípidos , Factores Sexuales , Tejido Adiposo/anatomía & histología , Tejido Adiposo/metabolismo , Animales , Bilis/química , Colesterol/sangre , Cricetinae , Grasas Insaturadas en la Dieta/metabolismo , Eritrocitos/metabolismo , Ácidos Grasos/biosíntesis , Ácidos Grasos/sangre , Ácidos Grasos/metabolismo , Femenino , Regulación de la Expresión Génica , Aceite de Linaza/farmacología , Metabolismo de los Lípidos/genética , Metabolismo de los Lípidos/fisiología , Hígado/anatomía & histología , Hígado/metabolismo , Masculino , Mesocricetus , Tamaño de los Órganos , Oxidación-Reducción , Receptores de Lipoproteína/metabolismo , Triglicéridos/metabolismo , Aumento de Peso
16.
Reprod Nutr Dev ; 45(4): 405-18, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16045889

RESUMEN

In order to meet dietary requirements, the consumption of alpha-linolenic acid (ALA, 18:3 n-3) must be promoted. However, its effects on triglyceride (TG) and cholesterol metabolism are still controversial, and may be dose-dependent. The effects of increasing dietary ALA intakes (1%, 10%, 20% and 40% of total FA) were investigated in male hamsters. ALA replaced oleic acid while linoleic and saturated FA were kept constant. Triglyceridemia decreased by 45% in response to 10% dietary ALA and was not affected by higher intakes. It was associated with lower hepatic total activities of acetyl-CoA-carboxylase (up to -29%) and malic enzyme (up to -42%), which were negatively correlated to ALA intake (r(2) = 0.33 and r(2) = 0.38, respectively). Adipose tissue lipogenesis was 2-6 fold lower than in the liver and was not affected by dietary treatment. Substitution of 10% ALA for oleic acid increased cholesterolemia by 15% but, as in TG, higher ALA intakes did not amplify the response. The highest ALA intake (40%) dramatically modified the hepatobiliary metabolism of sterols: cholesterol content fell by 45% in the liver and increased by 28% in the faeces. Besides, faecal bile acids decreased by 61%, and contained more hydrophobic and less secondary bile acids. Thus, replacing 10% oleic acid by ALA is sufficient to exert a beneficial hypotriglyceridemic effect, which may be counteracted by the slight increase in cholesterolemia. Higher intakes did not modify these parameters, but a very high dose resulted in adverse effects on sterol metabolism.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Metabolismo de los Lípidos , Hígado/enzimología , Ácido alfa-Linolénico/administración & dosificación , Animales , Colesterol/sangre , Colesterol/metabolismo , Cricetinae , Grasas Insaturadas en la Dieta/efectos adversos , Relación Dosis-Respuesta a Droga , Heces/química , Hígado/metabolismo , Masculino , Mesocricetus , Necesidades Nutricionales , Distribución Aleatoria , Triglicéridos/sangre , Triglicéridos/metabolismo , Ácido alfa-Linolénico/efectos adversos
17.
Ann Nutr Metab ; 46(5): 182-91, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12378041

RESUMEN

Reducing the ratio between essential fatty acids: C18:2 n-6/C18:3 n-3 down to 5 is recommended by Nutritional Guidelines. We studied the fatty acid (FA) changes in consumers' plasma following changes in livestock diet. First, a zootechnical study introduced 5% of extruded linseed into the diet of livestock to replace other oleaginous ingredients, and on an iso-nutritional values basis. The products from linseed-fed animals contained more n-3 fatty acids (precursor alpha-linolenic and derivatives obtained by elongations and desaturations) than control animal products (issued from animals fed without linseed), and more conjugated linoleic acids (CLA). The n-6/n-3 ratio was reduced by 54% in butter, 60% in meat and 86% in eggs. Following this, a double-blind, randomised, cross-over clinical study involving 75 healthy volunteers compared plasma and erythrocyte FA profiles in consumers of animal products (from livestock fed the linseed diet or from livestock fed standard diet). It showed modifications in the FA composition of the experimental human regimen with more C18:3 n-3 (1.65 vs. 0.75 g/day), and more n-3 derivatives. The C18:2 n-6/C18:3 n-3 ratio decreased (7 vs. 15). In volunteers' plasma, C18:3 n-3 increased in the essay group (0.93 vs. 0.44% of the FA), so did n-3 derivatives and CLA. The n-6/n-3 ratio decreased from 14.3 to 10.2. In erythrocytes, C20:5 n-3 increased in the essay group (0.59 vs. 0.45%) and so did C22:6 n-3. The n-6/n-3 ratio decreased in parallel from 4.2 to 3.8. Without any changes in consumers' eating habits, foodstuffs from animals fed linseed diets induced significant modifications of human plasma and erythrocyte fatty acid composition (comparable to that noted under the 'Cretan' diet) and a sharp increase in CLA.


Asunto(s)
Alimentación Animal , Animales Domésticos , Enfermedades Cardiovasculares/prevención & control , Ácidos Grasos/sangre , Lino , Adulto , Animales , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA