The association amongst visual, hearing, and dual sensory loss with depression and anxiety over 6 years: The Tromsø Study.

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.

Characteristics of endothelin receptors in the cerebral cortex and spinal cord of aged rats.

Characteristics of endothelin receptors were studied in male Fischer 344 rats at 4-, 15- and 24-months of age and [125I]ET-1 binding showed a single high affinity binding site in their cerebral cortex and spinal cord membranes. The density and affinity of ET binding sites were found to be similar in rats of various age groups. To determine the affinity of ET isotypes to ET-1 binding sites in cerebral cortex and spinal cord, competition studies were performed and K(i) values of ET-1, ET-2 and ET-3 for [125I] ET-1 binding sites were determined. It was found that ET-1 had 100 and ET-2 had 25-100 times lower K(i) values as compared to ET-3, indicating that ET receptors in cerebral cortex and spinal cord are of ETA type. In spinal cord, the K(i) values of ET-1 and ET-2 for ET receptor were found to be similar. However, in cerebral cortex the K(i) values of ET-1 were found to be at least 6 times lower than ET-2. It is inferred that there are two subtypes of ET(A) receptors, ET(A1) which have higher affinity for ET-1 in comparison to ET-2, as found in cerebral cortex and ET(A2) which have higher affinity for ET-2, as found in spinal cord. The K(i) and IC50 values of ET-1, ET-2, and ET-3 for [125I]ET-1 binding sites in cerebral cortex and spinal cord were found to be similar in 4-, 15- and 24-month-old rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of quality changes in walnut kernels (Juglans regia L.) by Vis/NIR spectroscopy.

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).

Protection of dehydrated chicken meat by natural antioxidants as evaluated by electron spin resonance spectrometry.

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.

Cocaine hydrochloride in poly(L-lactide) microspheres potentiates effects on the locomotion of rats+.

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.

Colour stability and lipid oxidation of fresh beef. Development of a response surface model for predicting the effects of temperature, storage time, and modified atmosphere composition.

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.

Photooxidation of oxymyoglobin. Wavelength dependence of quantum yields in relation to light discoloration of meat.

The reaction quantum yield for photooxidation of oxymyoglobin to metmyoglobin in dilute aqueous solution and in beef extract has been determined for seven wavelengths of irradiation in the UV-visible region and, for aqueous solution, ranges from 1·6 x 10(-2) (254 nm) to 7 x 10(-6) (546 nm) mol einstein(-1). When taken together with the molar absorptivity at the wavelength of irradiation, the photooxidation quantum yield constitutes an objective measure of the effectiveness with which monochromatic light promotes the formation of metmyoglobin in meat. This is discussed in relation to light-induced discoloration of frozen meat.

Colour and colour stability of hot processed frozen minced beef. Results from chemical model experiments tested under storage conditions.

Minced beef based on hot processed meat was found to show an improved red colour and, more significantly, to show a better colour stability with respect to brown discoloration, when compared to minced beef resulting from a traditional (cold) process. The colour was followed by tristimulus colorimetry during freezer storage (product temperature -18°C) in a display cabinet illuminated by fluorescent tubes. The development of brown discoloration seems to indicate other oxidative changes and to relate to rancidity as judged from a determination of thiobarbituric acid reactive substances in the mince surface. Fluorescent light and added salt, both known from chemical models to increase the autoxidation rate of red oxymyoglobin to brown metmyoglobin, greatly reduced the colour stability, especially for cold deboned meat. pH of the hot deboned meat was significantly higher (pH > 6·0) than that of the cold deboned meat (pH ranged from 5·5 to 5·8). The observations are discussed in relation to kinetic salt effect on the acid catalyzed autoxidation of oxymyoglobin and its role in the initiation of oxidative rancidity.

Colour stability of minced beef. Ultraviolet barrier in packaging material reduces light-induced discoloration of frozen products during display.

The colour stability of minced beef, as measured by tristimulus colorimetry during freezer storage in a display cabinet illuminated with fluorescent tubes (product temperature -18°C), was found to be significantly improved by an ultraviolet-light barrier in the packaging material. In general, a positive effect on colour stability of beef with barriers excluding light below 350 nm is to be expected at storage temperatures up to approximately 5°C. This prediction is based on calculations using the energy of activation for the thermal autoxidation of oxymyoglobin and the quantum yield at different wavelengths for the competitive photochemical autoxidation process.

Modified packaging as protection against photodegradation of the colour of pasteurized, sliced ham.

Carbon dioxide flushing and packaging under slight overpressure has been found to eliminate discoloration of vacuum-packed ham, normally encountered as a result of photooxidation of nitric oxide pigments during the first 24 h of display in illuminated cabinets. On exposure to light, even when the product is packed in high-vacuum, residual oxygen invariably present in the product gives rise to significant photochemical pigment degradation and general poor oxidative stability, and has warranted up to 4 days of dark storage prior to display. Replacement of the atmosphere with carbon dioxide, even when repeated, followed by the establishment of vacuum, does not yield a similar protection.

Effects of Dietary Rape Seed Oil, Copper(II) Sulphate and Vitamin E on Drip Loss, Colour and Lipid Oxidation of Chilled Pork Chops Packed in Atmospheric Air or in a High Oxygen Atmosphere.

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.

Oxidation in pre-cooked minced pork as influenced by chill storage of raw muscle.

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.

Influence of the oxidative quality of dietary oil on broiler meat storage stability.

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.

Influence of supranutritional vitamin E and copper on α-tocopherol deposition and susceptibility to lipid oxidation of porcine membranal fractions of M. Psoas major and M. Longissimus dorsi.

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.

Effect of residual oxygen on colour stability during chill storage of sliced, pasteurised ham packaged in modified atmosphere.

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.

Effects of chemical hurdles on microbiological and oxidative stability of a cooked cured emulsion type meat product.

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.

Warmed-over flavour in porcine meat - a combined spectroscopic, sensory and chemometric study.

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.

Effect of light and packaging conditions on the colour stability of sliced ham.

The colour fading of sliced ham displayed in chill cabinets has been found to be caused by the combined action of light and oxygen, and can be prevented by a combination of packaging in a plastic material with low oxygen transmission rate (OTR<4 cm(3)/m(2)/24h/atm), a high initial vacuum level (>99%), and cold storage in the dark until residual oxygen in the packaging has been consumed (4 days for >99% initial vacuum). UV-light permeability of the packaging material had no effect on colour stability. The colour was measured by tristimulus colorimetric measurements on the surface of ham packaged in packaging material with different OTR (60 and <4 cm(3)/m(2)/24h/atm) and UV-light permeability (transparent above 360 and above 250 nm), and the change in colour was monitored by the Hunter a value, the tristimulus colorimetry parameter found (by analysis of variance) to give the best correlation with the subjectively evaluated ham colour. For each of the four types of packaging material, three different initial vacuum levels (85, 95 and >99%) were used.

Effect of pre-slaughter physiological conditions on the oxidative stability of colour and lipid during chill storage of pork.

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.

Sensory and chemical analysis of cooked porcine meat patties in relation to warmed-over flavour and pre-slaughter stress.

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.