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1.
Int J Geriatr Psychiatry ; 33(4): 598-605, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29193338

RESUMEN

OBJECTIVE: To examine the longitudinal association of dual and single (vision and hearing) sensory loss on symptoms of depression and anxiety in older adults. METHODS: Two thousand eight hundred ninety adults aged 60 years or over who participated in the longitudinal population-based Tromsø Study, Norway, were included. The impact of objective vision loss, self-report hearing loss, or dual sensory loss on symptoms of depression and anxiety, as assessed by the Hopkins Symptom Checklist 10, was examined at baseline and 6-year follow-up using linear mixed models. RESULTS: Hearing loss had a cross-sectional relationship with increased depression (b = 0.1750, SE = 0.07, P = .02) and anxiety symptoms (b = 0.1765, SE = 0.08, P = .03); however, these relationships were not significant at the 6-year follow-up. Both vision loss only and dual sensory loss predicted increased depression scores at follow-up (b = 0.0220, SE = 0.01, P = .03; and b = 0.0413, SE = 0.02, P = .01, respectively). Adjustment for social isolation did not attenuate the main depression results. CONCLUSION: Dual sensory loss resulted in increased depression symptomatology over time and posed an additional long-term risk to depression severity beyond having a single sensory loss only. Only hearing loss is associated with anxiety symptoms. Older adults with vision, hearing, and dual sensory loss have different mental health profiles. Therefore, management and intervention should be tailored to the type of sensory loss.


Asunto(s)
Trastornos de Ansiedad/etiología , Trastorno Depresivo/etiología , Pérdida Auditiva/psicología , Trastornos de la Visión/psicología , Anciano , Anciano de 80 o más Años , Ansiedad , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Noruega , Factores de Riesgo , Aislamiento Social/psicología
2.
Eye (Lond) ; 27(11): 1281-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23970030

RESUMEN

PURPOSE: To examine the cross-sectional relationship between drusen, late age-related macular degeneration (AMD), and cognitive function. METHODS; We included 2149 stroke-free participants from the population-based Tromsø Study in Norway. Retinal photographs were graded for presence of drusen and AMD. Cognitive function was assessed using the verbal memory test (short verbal memory), digit-symbol coding test (processing speed), and the tapping test (psychomotor tempo). We assessed the relationship between drusen, late AMD, and cognitive test scores, adjusted for potential confounders. RESULTS: Late AMD was associated with decreased performance in the verbal memory test (standardized ß=-0.23, 95% confidence interval (CI): -0.51 to -0.01). Intermediate and large drusen were associated with decreased performance in the digit-symbol coding test (standardized ß=-0.14 and -0.19, 95% CIs: -0.23 to -0.05 and -0.29 to -0.09, respectively). Participants with large drusen were more likely to have test scores in the lowest quartile of the digit-symbol coding test (odds ratio (OR)=1.9, 95% CI: 1.1-3.5) and the tapping test (OR=1.6, 95% CI: 1.0-2.6), but not in the verbal memory test (OR=1.0, 95% CI: 0.6-1.6). CONCLUSIONS: The findings suggest a relationship between drusen deposition and reduced cognitive function. Although the relationships between drusen, late AMD, and the cognitive test results varied in strength and significance across the types of cognitive test, and may partly have been caused by residual confounding, it is not unlikely that a genuine but weaker relationship exists between drusen deposition and cognitive decline.


Asunto(s)
Cognición/fisiología , Degeneración Macular/fisiopatología , Drusas Retinianas/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Noruega , Estudios Prospectivos
3.
Acta Physiol Scand ; 182(3): 277-85, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15491406

RESUMEN

AIM: Diadenosine polyphosphates are present intracellularly and in extracellular fluid due to release from secretory vesicles in platelets, chromaffin cells and other cells. This study investigates effects of diadenosine pentaphosphate (AP5A) on heart muscle function. METHODS: Contractile force amplitude and action potential duration at 90% repolarization (APD90) were measured after challenge with AP5A 50 microm or isoproterenol 50-70 nM in guinea pig papillary muscles. Isoproterenol was given immediately after AP5A-exposure or after 45 min washout. AP5A was combined with antagonists to the purinergic P2 receptor (suramin 100 microm), the dinucleotide receptor [diinosine pentaphosphate 30 microm (IP5I)] or adenosine receptors [8-(P-sulfophenyl) theophylline 50 microm (8-SPT)]. RESULTS: Results are %-change (mean +/- SEM) from value before exposure. AP5A increased contractile force by 22 +/- 3%* (*P <0.05), and IP5I abolished this. AP5A prolonged APD90 by 7 +/- 2%*. AP5A significantly reduced response to isoproterenol acutely from 31 +/- 4* (controls) to 9 +/- 4% and after 45 min washout from 61 +/- 14* (controls) to 16 +/- 5%. 8-SPT abolished the sustained effect. Increase in contractile force by AP5A was confirmed in human atria trabecula preparations. CONCLUSION: AP5A increased contractile force and prolonged APD90. Contractile force increased by stimulation of the dinucleotide receptor in guinea pig myocardium. The sustained anti-beta-adrenergic effect of AP5A was due to adenosine receptor stimulation.


Asunto(s)
Fosfatos de Dinucleósidos/farmacología , Contracción Miocárdica/efectos de los fármacos , Vasoconstrictores/farmacología , Potenciales de Acción/fisiología , Agonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/farmacología , Animales , Femenino , Cobayas , Atrios Cardíacos/efectos de los fármacos , Humanos , Isoproterenol/farmacología , Masculino , Músculos Papilares/efectos de los fármacos , Antagonistas Purinérgicos , Receptores Purinérgicos P2 , Suramina/farmacología , Teofilina/farmacología
4.
Food Addit Contam ; 19 Suppl: 172-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11962705

RESUMEN

Materials based on renewable resources are being developed at an increasing rate. Today, the only biobased food-packaging materials used commercially on a major scale are based on cellulose. However, materials based on proteins, starch, polylactate and other renewable resources may be the food-packaging materials of tomorrow. The paper presents some of the different biobased materials and their potential as food-packaging materials.


Asunto(s)
Conservación de los Recursos Naturales , Embalaje de Alimentos/métodos , Polímeros/química , Biodegradación Ambiental , Biomasa , Embalaje de Alimentos/tendencias , Humanos
5.
J Agric Food Chem ; 49(12): 5790-6, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11743765

RESUMEN

Storage of walnut kernels in light and at room temperature, as is common practice, is detrimental to their sensory quality and shelf life. This study demonstrates that Vis/NIR spectroscopy, in combination with multivariate data analysis (chemometrics), is a most capable rapid method for monitoring the overall quality deterioration of walnut kernels. Spectral predictions of the sensory attributes nutty and rancid tastes by partial least-squares regression (PLSR) resulted in correlations (r(2)) of 0.77 and 0.86, respectively, whereas with PLSR prediction of the chemical parameter hexanal content a correlation (r(2)) of 0.72 was obtained. The study further establishes that storage in light results in pronounced oxidative changes, especially in walnuts stored at 21 degrees C, whereas dark storage at 5 degrees C results in walnuts without any trace of rancid taste during 25 weeks of storage at accelerated storage conditions (50% oxygen).


Asunto(s)
Nueces/química , Manipulación de Alimentos , Lípidos/aislamiento & purificación , Peróxidos/análisis , Espectrofotometría/métodos , Espectrofotometría Infrarroja/métodos
6.
Meat Sci ; 58(4): 347-57, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22062424

RESUMEN

The physiological condition of the live animal was found to significantly affect colour, lipid oxidation and water holding capacity of chill stored pork chops (M. Longissimus dorsi) in a study, where various pre-slaughter conditions were achieved by the following four treatments: (A) control; (B) subjected to treadmill exercise immediately prior to stunning; (C) given epinephrine injection 15 h prior to slaughter; and (D) given epinephrine injection 15 h before slaughter and further subjected to treadmill exercise immediately before stunning. The treatments resulted in variations in energy metabolites (glycogen, lactate, creatine phosphate, ATP) and ultimate pH (pH(u)), with the lowest pH(u) in chops from treatments A and B, and in significantly different tristimulus colour L(∗)-, a(∗)- and b(∗)-parameters, although the effect of treatment on colour was not consistent during the chill storage period of 6 days. Overall, chops from treatments A and B had significantly higher L(∗)- and b(∗)-values (were paler and less blue) than chops from C and D during storage under conditions typical for retail trade. The initial a(∗)-values were higher (redder) in chops from treatments A and B, but the colour, as judged by the a(∗)-values, was less stable in meat from these treatments compared with treatments C and D. Lipid oxidation, evaluated by thiobarbituric acid reactive substances (TBARS) in the fresh meat, and drip loss, measured after 6 days of storage, were both significantly higher in chops from treatments A and B compared to chops obtained from treatments C and D. Statistical analysis relating the pH and the level of various energy metabolites post-mortem in the individual animals to the measured quality parameters, revealed that pH(u) was the most important factor affecting product quality. In conclusion, over all product quality depends on obtaining a pH(u) in the narrow range where both meat quality parameters such as colour, lipid oxidation and drip loss as well as microbiological aspects have to be considered.

7.
Meat Sci ; 59(3): 229-49, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22062778

RESUMEN

Two independent sensory profiles were carried out to evaluate warmed-over flavour (WOF) development in cooked, chill-stored and reheated pork patties. The patties were derived from the Musculus semimembranosus of animals subjected to different pre-slaughter stress treatments. All patties were stored in oxygen permeable bags at 4°C for 0, 1, 2, 3 and 5 days to facilitate WOF development. In addition, thiobarbituric acid reactive substances (TBARS), conjugated dienes, pH, water content, total lipids and the fatty acid compositions of phosphatidyl choline (PC), phosphatidyl ethanolamine (PE) and total lipids, were measured in the cooked meat patties. A data analytical strategy involving Analysis of Variance-Partial Least Squares Regression (ANOVA-PLSR), to determine relationships between the design variables (WOF and pre-slaughter stress) and the sensory-chemical data, and PLSR to elucidate predictive links between the sensory and chemical data was utilised. WOF was found to involve the development of lipid oxidation derived nuance off-flavour and odour notes, e.g. rancid-like flavour and linseed oil-like odour, in association with a concurrent decrease in cooked pork meat-like flavour. The reduction in "meatiness", over the initial days, 0-2 of WOF development was attributed to the degradation of both, unstable sulfur-containing amino acids in meat proteins and sulfur-containing "meaty" aroma compounds. Whereas, at the later days, 3-5 of WOF development the "meaty" loss was ascribed to perceptual masking by lipid oxidation products. TBARS and conjugated dienes were found to be significant (P<0.05) predictors of the sensory terms related to the lipid oxidation aspect of WOF. Whilst the polyunsaturated fatty acid (PUFAs) contents of PE, PC and the total lipids were found to decrease with WOF development, reflecting their loss in lipid oxidation reactions. The sensory variation related to pre-slaughter stress appeared to be distinct from WOF variation and was described by a sour to sweet taste continuum. However, interactions were noted that indicated increasing pre-slaughter stress resulted in a decreased sensory perception of WOF. Moreover, pH and water content were found to significantly (P<0.05) predict the sensory effects resulting from pre-slaughter stress.

8.
J Agric Food Chem ; 48(11): 5548-56, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11087517

RESUMEN

Dehydrated chicken meat (a(w) = 0.20-0.35) made from mechanically deboned chicken necks can be protected against oxidative deterioration during storage by rosemary extract (at a sensory acceptable level of 1000 ppm, incorporated prior to drying). The efficiency of the rosemary extract was similar to that obtained by synthetic antioxidants in a reference product (70 ppm butylated hydroxyanisole and 70 ppm octyl gallate). Tea extract and coffee extract were less efficient than rosemary and synthetic antioxidants. Among the natural antioxidants tested, grape skin extract provided the least protection against oxidative changes in dehydrated chicken meat. Radicals in the product, quantified by direct measurement by electron spin resonance (ESR) spectrometry, developed similarly to headspace ethane, pentane, and hexanal, and to oxygen depletion both in unprotected and protected products. The ESR signal intensity and headspace hexanal both correlated with the sensory descriptor "rancidity" as evaluated by a trained sensory panel. Hexanal, as a secondary lipid oxidation product, showed an exponential dependence on the level of radicals in the product in agreement with a chain reaction mechanism for autoxidation, and direct ESR measurement may be used in quality control of dehydrated food products.


Asunto(s)
Antioxidantes , Conservación de Alimentos/métodos , Carne , Animales , Hidroxianisol Butilado , Pollos , Desecación , Espectroscopía de Resonancia por Spin del Electrón , Ácidos Grasos/análisis , Ácido Gálico/análogos & derivados , Lamiaceae , Carne/análisis , Extractos Vegetales , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
9.
Meat Sci ; 54(4): 377-84, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22060795

RESUMEN

Addition of 200 ppm all-rac-α-tocopheryl acetate to pig feed supplemented with 6% high-oleic rapeseed oil gave mitochondrial membranes, which had a lower rate of formation of free radicals as determined by ESR-spectroscopy using the spin-trapping technique. Addition of 175 mg/kg copper to the feed, with or without all-rac-α-tocopherol acetate addition was not pro-oxidative (or anti-oxidative). While these effects were similar for both the oxidative M. Psoas major (PM), and the glycolytic, M. Longissimus dorsi (LD), differences between muscles were characterised by a higher activity of ß-hydroxyacyl-coenzyme A-dehydrogenase (HAD) and citrate synthase (CS), and a lower activity of lactate dehydrogenase (LDH) in PM than in LD (p<0.001). The concentration of α-tocopherol in muscles, liver, and plasma was influenced by the α-tocopherol level in the feed (p<0.001). The concentration of fatty acids in microsomes was not influenced by dietary treatments, but was higher in PM than in LD. However, the total concentration of fatty acids in the mitochondria of PM was higher in pigs supplemented with all-rac-α-tocopheryl acetate.

10.
Meat Sci ; 54(4): 399-405, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22060798

RESUMEN

The critical level of residual oxygen to avoid light induced oxidative discoloration during chill storage of sliced, pasteurised ham packaged in modified atmosphere (20% carbon dioxide balanced with nitrogen in a 1:3 product to headspace volume ratio) was found to lie between 0.1 and 0.5% oxygen. In 0.5% oxygen light induced discoloration was significant, as detected by the tristimulus colorimetry redness parameter, when compared to the same product stored in the dark, while at 0.1 and 0.02% oxygen the colour was stable both in the dark and when exposed to light for up to 27 days in chill storage. Lipid oxidation, determined as 2-thiobarbituric acid-reactive substances, and total plate counts showed no difference between discoloured and colour stable products, although a trained panel in a triangle test could differentiate between the taste of ham from packages with 0.02 and 0.5% oxygen after 27 days of chill storage.

11.
Meat Sci ; 55(4): 483-91, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22061582

RESUMEN

Two combinations of hurdles, 2.0% lactate+0.5% acetate or 2.0% lactate+0.25 % glucono-delta-lactone (GdL), were both found to prevent growth of Listeria monocytogenes inoculated onto sliced saveloys manufactured with 60 or 150 ppm nitrite. The saveloys were packed in modified atmosphere (80% N(2)/20% CO(2)) using a film with low oxygen transmission rate (0.45 cm(3)/m(2)/atm/24 h) and stored at 5 or 10°C for up to 4 weeks. Changes in red colour (measured as Minolta a-values) and lipid oxidation [measured as thiobarbituric acid reactive substances (TBARS)] were low during storage at 5°C and unaffected by the storage conditions (±light). However, 2.0% lactate+0.25% GdL improved oxidative stability and led to significantly lower TBARS and significantly higher a-values. Levels of nitrosamines were low with values near the detection level. Although observed differences were small, members of a trained sensory panel were able to distinguish saveloys containing chemical hurdles from saveloys without. Judges most often mentioned flavour as being the deviating descriptor.

12.
Meat Sci ; 54(1): 49-57, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22063711

RESUMEN

Samples of fresh beef muscles (Longissimus dorsi) were packed under varying modified atmosphere conditions (20-80% oxygen) and stored at 2-8°C for 10 days. At 2 day intervals meat samples were analysed for surface colour and extent of lipid oxidation (TBARS). Response surface models for predicting the effects of temperature, storage time and modified atmosphere composition on colour stability and lipid oxidation were developed. Temperature and time were found to be the most important factors for retaining meat colour and minimizing lipid oxidation. However, the oxygen content also had a significant effect on both quality parameters. A stable interval of maintaining a good meat colour was found between 55 and 80% O(2). Response surface modelling was found to be very promising for modelling of chemical quality changes in meat stored under different conditions, but the large biological differences between animals may complicate the development of generally valid models.

13.
Meat Sci ; 54(1): 83-95, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22063716

RESUMEN

The effectiveness of applying rapid spectral techniques in the prediction of meat quality in relation to pre-slaughter stress and warmed-over flavour (WOF) was investigated. The effect of pre-slaughter stress on the development of WOF is a relatively new area of interest in WOF research. The present study investigated the relationship between pre-slaughter stress and WOF characteristics (after 0 to 5 days' storage) in porcine meat as evaluated by chemical, sensory and spectroscopic methods. Sensory evaluation, visual reflectance spectroscopy (VIS) and low-field (1)H NMR (LF-NMR) proved efficient in describing the different stress groups and the storage period, whereas fluorescence spectroscopy and the TBARS test were only able to follow WOF during storage. Near Infrared Reflectance (NIR) and Raman scatter showed a very weak relationship to pre-slaughter stress and levels of WOF during storage. Good correlations (up to r=0.93) of sensory terms were achieved with VIS and fluorescence spectroscopy and LF-NMR.

14.
Meat Sci ; 50(2): 211-21, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22060955

RESUMEN

The effect of addition of rapeseed oil (canola), CuSO(4) and vitamin E (all-rac-α-tocopheryl acetate) to pig diets on pork meat quality (lipid oxidation, colour and drip loss) was studied. Pigs were reared on ten different diets, either a control diet (no supplementation of rapeseed oil, CuSO(4) or vitamin E) or 6% rapeseed oil diets supplemented with CuSO(4) (0, 35 or 175mg/kg) and vitamin E (0, 100 or 200mg all-rac-α-tocopheryl acetate/kg). The natural content of vitamin E originating from feed ingredients amounted to 9-23mg vitamin E (α-tocopherol) per kg feed. Muscle vitamin E levels reflected the dietary intake and pigs fed the control diet had significantly lower levels than pigs fed rapeseed oil diets. The quality of fresh pork chops packed in air or in 80% O(2):20% CO(2) was followed during chill storage for 8 and 13 days, respectively. Colour, as measured by tristimulus colorimetry of pork chops packed in 80% oxygen atmosphere, was significantly improved with respect to redness when compared to chops packed in air, regardless of dietary treatment. The low vitamin E content in pigs fed the control feed significantly decreased a values and the oxidative stability of pork chops during chill storage compared to the other feeding groups. Packing of chops in a high-oxygen atmosphere increased lipid oxidation, especially in chops with low levels of vitamin E. Supplementation of rapeseed oil diets with 100 or 200mg vitamin E significantly decreased lipid oxidation of chill stored chops. Supplementation with CuSO(4) did not influence meat quality attributes (drip loss, colour stability and lipid oxidation) for any of the storage conditions.

15.
Meat Sci ; 45(4): 491-500, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22061672

RESUMEN

The effect of feeding supra-nutritional levels of α-tocopheryl acetate on its deposition in two porcine muscles of different metabolic rates (m. longissimus dorsi and m. psoas major) and the effect on meat quality (lipid oxidation, colour stability and drip loss) was studied. Pigs were fed a standard diet supplemented with three levels: 100, 200 and 700 mg/kg of α-tocopheryl acetate from the time of weaning to slaughter at 90kg live weight. Muscle α-tocopherol levels were linearly related to the logarithm of dietary α-tocopheryl acetate supplementation and the linear relationship was estimated for the two muscles. The levels of α-tocopherol in the two muscles differed by a parallel displacement with consistently higher α-tocopherol levels in m. psoas major compared to m. longissimus dorsi. Dietary α-tocopheryl acetate supplementation significantly reduced lipid oxidation as measured by thiobarbituric acid reactive substances (TBARS) in both raw and cooked meat during storage at 4 °C for 6 days. Drip loss and colour stability of raw muscles were not affected by dietary α-tocopheryl acetate levels, 100mg α-tocopheryl acetate/ kg feed resulted in sufficient α-tocopherol levels in muscles to ensure minimum drip loss and optimum colour stability.

16.
Meat Sci ; 46(2): 191-7, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22062042

RESUMEN

During storage for four days at 4 °C of pre-cooked minced pork, lipid oxidation measured as thiobarbituric acid reactive substances (TBARS) and as hexanal by solid phase microextraction was found to depend on the level of lipid hydroperoxides rather than on the TBARS in the raw muscle (M. Longissimus dorsi). Storage for up to six days at 4 °C, prior to mincing and cooking, resulted in a decrease in lipid hydroperoxides measured as conjugated dienes and in increasing TBARS-value in the raw muscle, and in a pre-cooked product with better oxidative stability. The correlation coefficient between accumulation of TBARS and hexanal in the pre-cooked meat was 0.98, indicating that the new technique using solid phase microextraction with subsequent GC-analysis for determination of hexanal can be used as an alternative technique to describe lipid oxidation in pre-cooked meat.

17.
Meat Sci ; 47(3-4): 211-22, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22062734

RESUMEN

Broilers were fed a high fat diet containing 11% oil (9% rapeseed oil, 2% soya bean oil) and the oil was given either as fresh (peroxide value of 1 meqv. O(2)kg(-1) oil) or as highly oxidised (peroxide value of 156 meqv. O(2)kg(-1) oil). Diets were supplemented with 46 mg all-rac-α-tocopheryl acetate kg(-1) diet, resulting in a tocopherol content of 80.8 mg α-tocopherol and 58.6 mg γ-tocopherol per kg diet in the fresh oil diet and of 44.0 mg α-tocopherol and 18.3 mg γ-tocopherol per kg diet in the oxidised oil diet, respectively, reflecting the degradation of the natural occurring tocopherols in the oxidised diet. Only minor differences were seen with respect to fatty acid composition in muscles from birds fed the two diets. The oxidation of the dietary oil lowered lipid stability significantly (p < 0.01) in both raw and precooked meats during chill storage, whereas only minor effects on the stability of frozen meat were seen. Tocopherol levels were significantly lower (p < 0.01) in muscles from birds fed the oxidised oil diet, explaining the decreased lipid stability of meat from these birds. Thigh meat was more susceptible to lipid oxidation during storage than breast meat, regardless of dietary treatment, although thigh meat had markedly higher tocopherol levels than breast meat. The molar ratio of PUFA > 18:2 (polyunsaturated fatty acids with three or more double bonds) to α-tocopherol was significantly (p < 0.01) higher in thigh meat compared with breast meat, explaining the lower stability of the former during storage.

18.
Poult Sci ; 74(12): 1984-94, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8825589

RESUMEN

A total of 300 female broiler chickens were reared from day-old to 10 d of age on the same starter diet. Then they were divided into five groups, receiving a control diet (Group 1) relatively rich in fat (14.3%) and unsaturated fatty acids (87.6%) and standardized with respect to vitamins and minerals, supplemented with 100 mg (Group 2) and 500 mg (Group 4) of RRR-alpha-,gamma-,delta-tocopheryl acetate/kg feed (40.6% alpha-, 41.1% gamma-, 18.3% delta-) or 100 mg (Group 3) and 500 mg (Group 5) all-rac-alpha-tocopheryl acetate/kg feed until slaughter at 6 wk of age. No differences between the supplemented groups were observed with respect to weight gain, feed consumption, packed cell volume (PCV), plasma enzyme activities of creatine kinase (CK) and glutathione peroxidase (GSH-Px), fatty acid composition, and enzyme activities of citrate synthase (CS), and total lactate dehydrogenase (LDH), and 3-OH-acyl-coenzyme A-dehydrogenase (HAD) of breast (Pectoralis major) and thigh (Gastrocnemius interna) muscle. Increasing levels of alpha-, gamma-, and delta-tocopherol were found in blood plasma with increasing dietary levels of these tocopherols. Only alpha-tocopherol was detectable in skeletal muscle and in higher concentrations in thigh than in breast muscle. Hemolysis in vitro and plasma activity of aspartate aminotransferase (ASAT) were lower (P < .01) in Groups 2 and 4 than in Groups 3 and 5. Interactions were observed between dietary type and concentration of tocopherols for plasma CK, GSH-Px, Na+, and K+. No measurable excretion of ethane and pentane was observed in any of the groups. The findings indicate that the oxidative stress in the live animals was minimal. The mixture of natural source RRR-alpha-,gamma-,delta-tocopherols was as efficient in protecting the live chickens as the all-rac-alpha-tocopheryl acetate, when provided on a weight basis as judged from the chosen in vivo parameters of vitamin E status.


Asunto(s)
Mataderos , Pollos/metabolismo , Músculo Esquelético/química , Vitamina E/análogos & derivados , Vitamina E/análisis , Vitamina E/sangre , alfa-Tocoferol/análogos & derivados , Alimentación Animal/análisis , Animales , Aspartato Aminotransferasas/sangre , Citrato (si)-Sintasa/análisis , Creatina Quinasa/sangre , Ácidos Grasos/análisis , Femenino , Alimentos Fortificados , Glutatión Peroxidasa/sangre , L-Lactato Deshidrogenasa/análisis , Carne/análisis , Músculo Esquelético/enzimología , Oxidación-Reducción , Potasio/sangre , Distribución Aleatoria , Sodio/sangre , Tocoferoles , Vitamina E/química , Vitamina E/farmacología
19.
Poult Sci ; 74(12): 2048-56, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8825596

RESUMEN

Oxidative stability of muscle from broilers fed 1) basal feed; 2) basal feed supplemented with 100 mg of a mixture of natural source RRR-alpha-,gamma-,delta-tocopheryl acetate/kg feed; 3) basal feed supplemented with 100 mg of synthetic all-rac-alpha-tocopheryl acetate/kg feed; 4) basal feed supplemented with 500 mg of a mixture of natural source RRR-alpha-,gamma-,delta-tocopheryl acetate/kg feed; or 5) basal feed supplemented with 500 mg of synthetic all-rac-alpha-tocopheryl acetate/kg feed, was evaluated during chill and freezer storage by determination of thiobarbituric acid reactive substances (TBARS). The oxidative stability of precooked muscle was investigated in a chill storage experiment and in a model system with accelerated oxidation. The basal feed contained a standard added amount of 46 mg all-rac-alpha-tocopheryl acetate/kg feed. Furthermore, the basal feed had a high natural content of vitamin E, resulting in a dietary vitamin E level in the control feed of 72 mg alpha-tocopherol and 69 mg gamma-tocopherol, a level that provided a reasonable oxidative stability for the meat. In spite of this, raising the dietary vitamin E level resulted in improved oxidative stability of broiler muscle during storage. Supplementation of broiler feed with 100 mg all-rac-alpha-tocopheryl acetate/kg, resulting in a total alpha-tocopherol content of 198 mg/kg feed, was found to be sufficient to improve stability of precooked broiler breast and precooked thigh muscles during chill storage, and further to ensure stability of raw meat during chill and freezer storage. The mixture of natural source RRR-alpha-,gamma-,delta-tocopherol was less effective in protecting broiler muscles than the synthetic all-rac-alpha-tocopherol, when compared on a weight basis.


Asunto(s)
Alimentación Animal/normas , Pollos , Manipulación de Alimentos/métodos , Carne/normas , Vitamina E/análogos & derivados , alfa-Tocoferol/análogos & derivados , Alimentación Animal/análisis , Animales , Femenino , Alimentos Fortificados , Alimentos Congelados/normas , Carne/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Tocoferoles , Vitamina E/farmacología
20.
Methods Find Exp Clin Pharmacol ; 17(9): 597-600, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8786673

RESUMEN

Stress-related effects can often interfere with studies of behavioral pharmacology in animals. This is known to occur where frequent dosing is required as in the study of drugs of abuse. A depot system capable of eliciting a pharmacodynamic response over an extended period would circumvent the need for frequent dosing. Cocaine hydrochloride was incorporated in 4.2 microns median diameter (geometric standard deviation 1.7) poly(L-lactide) microspheres at a concentration of 20% w/w. Seventy percent of the drug load was released in the period from 1-8 h. Studies of the locomotion of rats (n = 10/group) in an open field demonstrated a baseline movement of approximately 0.1 m/h after the intraperitoneal administration of microspheres in saline, or saline alone. Ten milligram of cocaine in saline increased the movement of rats to > 3 m/h for a period of 1 h following injection. The distance travelled by rats after administration of 10 mg of cocaine in microspheres was > 3 m/h for a period up to 6 h. Cocaine delivered in microspheres significantly increased the drug action (0.022 < p < 0.032). Particulate carriers were used to deliver small quantities of drug that overcame the need for multiple dosing of experimental animals to achieve extended behavioral effects.


Asunto(s)
Cocaína/farmacología , Locomoción/efectos de los fármacos , Animales , Masculino , Microscopía Electrónica de Rastreo , Microesferas , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
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