Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Food Analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
PubMedDate not supplied

Matrix effects in quantitative pesticide analysis using liquid chromatography-mass spectrometry.

Combined liquid chromatography-mass spectrometry using electrospray or atmospheric-pressure chemical ionization has become an important tool in the quantitative analysis of pesticide residues in various matrices in relation to environmental analysis, food safety, and biological exposure monitoring. One of the major problems in the quantitative analysis using LC-MS is that compound and matrix-dependent response suppression or enhancement may occur, the so-called matrix effect. This article reviews issues related to matrix effects, focusing on quantitative pesticide analysis, but also paying attention to expertise with respect to matrix effects acquired in other application areas of LC-MS, especially quantitative bioanalysis in the course of drug development.

Artifacts↗
PubMed2006

An evaluation of renal inpatient meals against Renal Nutrition Group standards.

BACKGROUND: The Renal Nutrition Group (RNG) of the British Dietetic Association has developed standards for the nutritional composition of meals provided to renal patients in hospital. However, no data are available as to whether these are achievable. The purpose of this study was to determine whether renal inpatient meals can meet the standards set by the RNG. METHOD: A prospective 10-day weighed food analysis of hospital meals provided to renal patients was undertaken. Two sample meals were analysed at each mealtime to include (1) the most energy dense choice and (2) the most frequent patient choice (FPC). RESULTS: Energy dense choice meals achieved the standard for protein provision on 90% of days, but provided too little energy on 100% of days (for men) and on 30% of days (for women). Although daily standards for potassium were met on 70% of days, those for sodium and phosphate were exceeded. FPC meals met the daily standards for potassium, sodium and phosphate on at least 80% of days, but provided too little protein on 40% of days and too little energy on 100% of days (for men and women). CONCLUSION: The majority of hospital meals fail to meet the RNG standards. Problems exist in providing sufficient energy and protein whilst restricting sodium, potassium and phosphate.

Diet Records↗
PubMed2006

Pacemaker and ICD generator malfunctions: analysis of Food and Drug Administration annual reports.

CONTEXT: Pacemakers and implantable cardioverter-defibrillators (ICDs) are complex medical devices proven to reduce mortality in specific high-risk patient populations. It is not known if increasing device complexity is associated with decreased reliability. OBJECTIVES: To analyze postapproval annual reports submitted to the US Food and Drug Administration (FDA) by manufacturers of pacemakers and ICDs to determine the reported number and rate of pacemaker and ICD malfunctions and to assess trends in device performance. DESIGN AND SETTING: Pacemaker and ICD annual reports submitted to the FDA for the years 1990-2002 were reviewed. A pacemaker or ICD generator was defined as having malfunctioned if it was explanted due to an observed malfunction, returned to the manufacturer, and confirmed by the manufacturer to be functioning inappropriately. Leads and biventricular devices were not included in the study. Deaths were attributed to device malfunction only if they were witnessed, the malfunction immediately led to the death, and the malfunction was confirmed by the manufacturer. MAIN OUTCOME MEASURES: Number of implanted pacemaker and ICD generators; number of reported malfunctions; and annual malfunction replacement rates. Generator malfunction replacement rates were defined as the annual number of replacements due to confirmed malfunction divided by the annual number of implants. RESULTS: During the study period, 2.25 million pacemakers and 415,780 ICDs were implanted in the United States. Overall, 17,323 devices (8834 pacemakers and 8489 ICDs) were explanted due to confirmed malfunction. Battery/capacitor abnormalities (4085 malfunctions [23.6%]) and electrical issues (4708 malfunctions [27.1%]) accounted for half of the total device failures. The annual pacemaker malfunction replacement rate per 1000 implants decreased significantly during the study, from a peak of 9.0 in 1993 to a low of 1.4 in 2002 (P = .006 for trend). In contrast, the ICD malfunction replacement rate per 1000 implants, after decreasing from 38.6 in 1993 to 7.9 in 1996, increased markedly during the latter half of the study, peaking in 2001 at 36.4 (P = .04 for trend). More than half of the reported ICD malfunctions occurred in the last 3 years of the study. Overall, the annual ICD malfunction replacement rate was significantly higher than the pacemaker malfunction replacement rate (mean [SD], 20.7 [11.6] vs 4.6 [2.2] replacements per 1000 implants; P<.001; rate ratio, 5.9 [95% confidence interval, 2.7-9.1]). Sixty-one deaths (30 pacemaker patients, 31 ICD patients) were attributable to device malfunction. CONCLUSIONS: This study demonstrates that thousands of patients have been affected by pacemaker and ICD malfunctions, the pacemaker malfunction replacement rate has decreased, the ICD malfunction replacement rate increased during the latter half of the study, and the ICD malfunction replacement rate is significantly higher than that for pacemakers. Although pacemakers and ICDs are important life-sustaining devices that have saved many lives, careful monitoring of device performance is still required.

Defibrillators, Implantable↗
PubMed1998

The contingency of fitness: an analysis of food restriction on the macroptery-reproduction trade-off in crickets.

We examined the effect of food limitation on fitness trade-offs between macroptery and time spent calling in the wing-dimorphic cricket, Gryllus firmus. The results of previous studies have shown that, under optimal conditions, the proportionate time that males spend calling (with respect to neighbouring males) is directly associated with female attraction, and that micropterous (short-winged: SW) males call longer than macropterous (long-winged: LW) males (Crnokrak & Roff 1995, Animal Behaviour, 50, 1475-1481). Because crickets were examined under optimal conditions, these studies did not attempt to address how or whether fitness trade-offs change with the environment. In the present study, we allowed crickets ad libitum access to water, but restricted food intake to the minimum amount that would keep them alive for 20 days. On average, SW males called longer than LW males on 18 of 20 days in the stressed group, and 17 of 20 days in the control group. For both groups, SW males also attracted more females more often than did LW males. Although the absolute call durations decreased in the stressed group compared with the control group, the relative call durations remained approximately the same, as did the proportion of females moving towards the SW male. Cumulative call distributions showed that LW males called little after 10 days of adult life; the amount of time SW males spent calling seemed constant for the duration of the experiment. Copyright 1998 The Association for the Study of Animal Behaviour

Journal Article↗
PubMed1998

"Extravagances" during weight reduction, an analysis of food preference and selection.

As part of a behavioural modification programme for weight reduction in outpatients, obese clients [body mass index (BMI) 41.5+/-5.9 kg/m2], planned to eat once a week, an "extravagance", defined as a highly desired food in controlled quantities. Women (N=65) chose sweets as an "extravagance" more often than did men (42 vs. 17%), whereas men (N=21) preferred alcoholic beverages (44 vs. 16%). The majority described eating the "extravagance" as an enjoyable experience. Fifty out of 69 patients named a food dish as one of the three things that they liked best to eat or drink, 39 listed different kinds of sweets and 29 had a preference for alcoholic beverages. Foods that the patients perceived as a potential contribution to their weight problems were mainly sweets, food dishes and sandwiches.

Adult↗
PubMed1985

[Analysis of proteins in food with electrophoretic and chromatographic methods].

The efficiency of electrophoretic methods (gel electrophoresis, isoelectric focusing, twodimensional techniques) and of chromatographic methods (size exclusion and ion exchange chromatography, reversed phase HPLC) to analyze proteins in foods is reviewed. Several selected applications are discussed in detail. The large diversity of proteins in a particular food results in a unique electrophoretic or chromatographic pattern, that can be used for identification purposes, by means of the so called indicator proteins. The adaptability and resolving power of the methods assure their extended application to many protein containing foods. The uniqueness of the patterns obtained warranties differentiations of even closely related animal or plant foods as well as mixtures of them. The methods also allow quantitative determinations of mixtures of foods. Their ease of handling and good reproducibility and reliability favours their use in routine analyses. Numerous investigations on fish, meat and derived products, non-meat proteins in meat products, milk, cheese, cereals and products made of cereals, oilseed proteins, legumes, fruits and vegetables described in the literature are here presented.

Animals↗
PubMed2000

Hydrazine reagents as derivatizing agents in environmental analysis--a critical review.

Hydrazine reagents are a well-known group of derivatizing agents for the determination of aldehydes and ketones in liquid and gaseous samples. Within this article, the most important hydrazine reagents are critically summarized, and their major applications in different fields, including environmental analysis, food chemistry and industrial analysis are introduced. As 2,4-dinitrophenylhydrazine (DNPH) is the basic reagent for several international standard procedures, its properties are discussed in detail. Particular focus is directed on the chemistry of the hydrazine reagents, and chemical interferences are considered. Recent methods for the determination of various oxidants using hydrazine reagents are presented as well. Due to limited space, this review does not cover the related field of carbohydrate analysis, although many chemical aspects are similar.

Aldehydes↗
PubMed1989

A pharmacological analysis of food intake regulation in rats treated neonatally with monosodium L-glutamate (MSG).

Studies were conducted to examine deficits in food intake regulation in MSG-treated rats that result from known or suspected damage to neurotransmitter systems involved in feeding. Male rats were injected with either MSG (4 mg/g) or sodium chloride on postnatal days 2 and 4 (MSG-Lo) or postnatal days 2, 4, 6 and 8 (MSG-Hi). As adults, MSG-treated and control rats (n = 12/group) were examined for deficits in pharmacologically elicited feeding and other measures of food intake regulation. A second group of MSG-treated (n = 9/group) and control rats (n = 12) were used to measure basal blood pressure and nociceptive reactivity in adulthood. Organ weights, body weight and neuropeptide Y (NPY) content in brain regions were determined at the end of the study. MSG-Hi rats consumed significantly less food than controls during the dark part of the light cycle. Both MSG-Hi and MSG-Lo groups ate significantly less food than controls after a 48-hour fast. MSG-Hi and MSG-Lo rats consumed significantly less food than controls in response to 1.0 mg/kg morphine. MSG-Hi rats consumed significantly less food than controls during the dark phase and significantly more food than controls during the light phase in response to naloxone (1.0 mg/kg). MSG-Lo ate significantly more than controls in response to 0.1 mg/kg guanfacine. MSG-Hi and MSG-Lo showed a significant attenuation in diazepam-stimulated feeding when compared to controls. Blood pressure was significantly lower in both MSG-Hi and MSG-Lo rats compared to controls. Tail flick latencies were not altered by MSG-treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

A behavioral economics analysis of food choice in humans.

Three studies on the behavioral economics of food choice were presented. In Experiment 1 subjects were provided a choice of working for food on concurrent VR4 VR20 schedules, and subjects allocated the majority of their responding to the VR4 schedule. Subjects in Experiment 2 were provided a choice between two foods differing in ratings of subjective liking. The lower rated food was available on an FR1 component of a concurrent schedule, while the higher rated food was available on the other component across six comparisons ranging from FR1 through VR32. Subjects initially chose to work for the higher rated food, but as the constraints for this food increased, subjects chose to work for the lower rated food. In Experiment 3, subjects were provided the choice of a breakfast they liked or the monetary equivalent during deprivation and non-deprivation conditions. The food and money were first compared on equal FR1 schedules. Schedule requirements for money were subsequently maintained on a VR2 schedule, while access to food was presented in four phases from VR4 through VR32. Under deprivation, subjects allocated their time to get the preferred food instead of money only at the FR1 FR1 comparison. Under non-deprivation subjects allocated almost all their responding to work for money. These results suggest that the laboratory choice task is sensitive to schedule differences when food is used as a reinforcer, that subjective liking and schedule constraints for food are both important in determining food choice, and that alternative reinforces can complete with food, but the effect is dependent on both the level of deprivation and constraints on access to food.

Adolescent↗