Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MEAT”

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 883 records · Page 49Linked to original sources

Meat, milk, saturated fatty acids, the Pro12Ala and C161T polymorphisms of the PPARgamma gene and colorectal cancer risk in Japanese.

The peroxisome proliferator-activated receptor gamma (PPARgamma) gene plays important roles in energy homeostasis. To examine interactions between consumption of foods and fatty acids and the Pro12Ala and C161T (His447His) polymorphisms for colorectal cancer, we performed two case-control studies in Japanese. In study 1, there were 128 colorectal cancer cases and 238 non-cancer controls, and in study 2 there were 257 cases and 771 (age- and sex-matched) non-cancer controls. Assessment of food and nutrients consumption in study 1 was via a nine-item questionnaire, while in study 2 assessment of consumption was according to a more detailed semiquantitative food frequency questionnaire. Consumption of foods and fatty acids was divided into low, moderate and high groups. The overall frequency of the Ala allele was <4%, and the frequencies of the Pro/Pro + C/C and Pro/Pro + (C/T + T/T) genotypes were 70-73% and 20-26%, respectively. Compared with subjects with low meat intake and the Pro/Pro + C/C genotype, those with high meat consumption and the same genotype had a stronger increased risk in study 1 [OR, 2.88; 95% CI, 1.14-7.30; P for trend = 0.02], but a positive association with processed meat consumption was greatest in those with the Pro/Pro + (C/T + T/T) genotype (P for trend = 0.05) in study 2. Likewise, high consumption of saturated fatty acids and milk appeared to confer marginal increased risk and stronger decreased risk, respectively, in those with the Pro/Pro and Pro/Pro + C/C genotypes (OR, 1.35 and 0.65; 95% CI, 0.93-1.96 and 0.43-1.00; P for trend = 0.10 and 0.06). Further large-scale studies are needed to determine colorectal cancer risk according to relationships between the PPARgamma gene polymorphisms and dietary intakes of meat, processed meat, milk and saturated fatty acids in Japanese with very low frequency of the Ala allele.

Adult↗

The rapid estimation of microbial contamination of raw meat by measurement of adenosine triphosphate (ATP).

Bacteria were separated from raw meat homogenate by a simple three-stage process. Centrifugation (10 s at 2000 g) removed coarse particles; stirring with the cation exchange resin Bio-Rex 70 removed smaller particles and filtration through 0.22 micron membranes removed soluble materials. By this process 70-80% of the microbial populations of meat homogenates were consistently isolated on the filters. A linear relationship was found between log10 microbial ATP and log10 colony count of meat over the range 10(5)-10(9) cfu/g. The value of ATP/cfu for meat samples was within the range previously reported for pure cultures. These data indicated that ATP extracted from the filters originated from bacteria in the meat samples. Several samples can be analysed simultaneously in an elapsed time of 20-25 min. The variability associated with estimates of both colony counts and ATP levels has been determined.

Adenosine Triphosphate↗

Effects of gaseous environment and temperature on the storage behaviour of Listeria monocytogenes on chicken breast meat.

Portions of skinless chicken breast meat (pH 5.8) were inoculated with a strain of Listeria monocytogenes and stored at 1, 6 or 15 degrees C in (1) aerobic conditions; (2) 30% CO2 + air; (3) 30% CO2 + N2; and (4) 100% CO2. When samples were held at 1 degree C the organism failed to grow under any of the test conditions, despite marked differences between treatments in spoilage rate and ultimate microflora. At 6 degrees C counts of L. monocytogenes increased ca 10-fold in aerobic conditions before spoilage of the meat, but only when the inoculum culture was incubated at 1 degree C rather than 37 degrees C. In CO2 atmospheres growth of L. monocytogenes was inhibited on meat held at 6 degrees C, especially under 100% CO2. By contrast, storage at 15 degrees C led to spoilage of the meat within 2 d, in all gaseous environments, and listeria levels increased up to 100-fold. Differences in the behaviour of L. monocytogenes on poultry and red meats are discussed.

Aerobiosis↗

Simultaneous detection of Carnobacterium and Leuconostoc in meat products by multiplex PCR.

AIMS: To develop a multiplex PCR approach for simultaneous detection of Leuconostoc and Carnobacterium and its validation in meat products. METHODS AND RESULTS: Two multiplex PCR assays were developed using newly designed 16S rDNA-directed primers adapted to the current taxonomic situation of genera Leuconostoc and Carnobacterium that allow: (i) simultaneous detection of both genera, and members of the nonmotile species of genus Carnobacterium and (ii) identification in a single assay of the nonmotile species C. divergens, C. maltaromicum and C. gallinarum. Sensitivity values of 10(3) and 10(4) CFU g(-1) were determined for multiplex PCR detection of Carnobacterium and Leuconostoc, respectively, following artificially inoculated meat trials. In addition, both multiplex PCR assays were validated in 14 naturally contaminated samples covering nine types of meat products. Results obtained by colony identification were confirmed by PCR detection. CONCLUSIONS: The methods described in this study provide a rapid and reliable tool for PCR detection of Carnobacterium and Leuconostoc, in meat products, and for colony identification. SIGNIFICANCE AND IMPACT OF THE STUDY: This multiplex PCR approach will help in the analysis of the spoilage microbiota of refrigerated vacuum-packaged meat product in order to determine the appropriate preservation method.

Animals↗

A salmonellosis outbreak linked to internally contaminated pork meat.

In August 1995, we investigated an outbreak of salmonellosis among patrons who attended a church camp in southern Sydney. Of the 73 attendees interviewed, 22 reported a gastroenteritis illness within two days of the conclusion of the camp, with one attendee hospitalised. Two stool specimens, one from each of two attendees, were both positive for Salmonella typhimurium phage type 9. A cohort study of 68 attendees established a statistically significant association between illness and the consumption of de-boned roast pork (estimated relative risk infinite, p = 0.03) and between illness and the degree of cooking of the pork meat (chi 2 for trend 5.8, p < 0.02). The outbreak was most likely caused by consumption of roast pork that had been internally contaminated during the de-boning process. Meat and meat products that may be internally contaminated, such as de-boned meats, should be thoroughly cooked. Guidelines about minimum cooking temperatures of meats liable to internal contamination should be developed for commercial food handlers in Australia.

Adolescent↗

Improved bioluminescent enzyme immunoassay for the rapid detection of Salmonella in chicken meat samples.

AIMS: To evaluate an improved bioluminescent enzyme immunoassay (BEIA) using biotinylated firefly luciferase for the rapid detection of Salmonella in naturally contaminated chicken meat samples. METHODS AND RESULTS: Capture agents and lipopolysaccharide (LPS) extraction reagents for Salmonella were investigated to improve the sensitivity of the BEIA. Also, the use of Oxoid SPRINT (Simple Pre-enrichment and Rapid Isolation New Technology) as a pre-enrichment and selective medium for 26-h BEIA detection of Salmonella in chicken meat samples was examined. The use of polymyxin B as a capture agent on solid support and 3-[(3-Cholamidopropyl) dimethylammonio] propanesulfonic acid (CHAPS) for extraction of the LPS facilitated sensitive detection of Salmonella. Of 120 chicken meat samples, 25 samples were positive using the improved BEIA with the SPRINT and 25 samples were positive using the SPRINT followed by the standard isolation methods. CONCLUSIONS: The improved BEIA, in which polymxin B was used as a capture agent and CHAPS was used for extraction of the antigen, had a sensitivity of 96.0% and a specificity of 98.9% for the detection of Salmonella in chicken meat. SIGNIFICANCE AND IMPACT OF THE STUDY: The improved BEIA combined with the SPRINT medium for the detection of Salmonella in chicken meat samples produced comparable results to the culture methods in 26 h.

Animals↗

Polymorphism of the N-acetyltransferase 2 gene, red meat intake, and the susceptibility of hepatocellular carcinoma.

OBJECTIVE: Carcinogenic aromatic amines, derived from cooked meat, are activated or inactivated by hepatic N-acetyltransferase (NAT). The aim of this study was to evaluate the relationship of NAT2 genetic polymorphisms with hepatocellular carcinoma (HCC), with special reference to the interaction of dietary habits. METHODS: Peripheral white blood cell DNA from 185 HCC patients and 185 matched controls were genotyped for NAT2 by a polymerase chain reaction-restriction fragment length polymorphism method. All the subjects studied were chronic viral hepatitis B or C carriers with liver cirrhosis. Dietary habits of the subjects were assessed using a semiquantitative food frequency questionnaire. RESULTS: There was no association between the susceptibility of HCC and the overall NAT2 genotypes. However, in rapid acetylators (with two wild type NAT2*4 alleles), there was a trend of increased HCC risk from low to intermediate and high red meat intake (OR = 1, 2.66, 3.89; p(trend) = 0.016), even when adjusted for family history of HCC and habitual alcohol drinking. The interaction between red meat intake and the NAT2*4 acetylator status for an increased risk of HCC was significant (p = 0.007). CONCLUSIONS: Polymorphisms of the NAT2 gene may confer different susceptibilities to the effect of red meat intake on HCC. In rapid acetylators with chronic viral hepatitis-related cirrhosis, red meat intake may play a role in hepatocarcinogenesis.

Aged↗

Fat, fiber, meat and the risk of colorectal adenomas.

OBJECTIVE: The aim of this study was to determine the relationship between fat, fiber, and meat intake, and risk of colorectal adenoma recurrence. METHODS: We determined adenoma recurrence and dietary intake for 1,520 participants in two randomized trials: The Antioxidant Polyp Prevention Study and Calcium Polyp Prevention Study. Subjects underwent baseline colonoscopy with removal of all adenomas, and dietary intake was estimated with a validated semiquantitative food frequency questionnaire. Follow-up colonoscopy was performed 1 and 4 yr later. Pooled risk ratios for adenoma recurrence were obtained by generalized linear regression, with adjustment for age, sex, clinical center, treatment category, study, and duration of observation. RESULTS: In the total colorectum, fiber intake was weakly and nonsignificantly associated with a risk for all adenomas (RR quartile 4 vs quartile 1=0.85, 95% CI 0.69-1.05) and advanced adenomas (RR=0.88, 95% CI 0.54-1.44). Associations were stronger for adenomas in the proximal colon (RR=0.73, 95% CI 0.56-0.97) and some fiber subtypes (fruit and vegetable, grain). There was no association between fat or total red meat intake and risk of adenoma or advanced adenoma recurrence. However, when considering other meats, risk (quartile 4 vs quartile 1) for advanced adenoma was increased for processed meat (RR=1.75, 95% CI 1.02-2.99) and decreased for chicken (RR=0.61, 95% CI 0.38-0.98). CONCLUSION: The inverse associations between fiber intake and risk of adenoma recurrence we observed are weak, and not statistically significant. Our data indicate that intake of specific meats may have different effects on risk.

Adenoma↗

Virus warts in meat handlers.

An epidemiological study has been made of virus warts on the hands of all workers in a large meat processing factory. The meat handled is pork and beef. A total of 1141 employees were examined, 687 of whom were constantly handling meat. The plant outline and the work of the 144 workers in the butchery section are described in detail. The prevalence of warts in meat handlers was 33.6-70.4% in different sections. The prevalence in non-meat handlers varied from 18.2% to 44.4%. Half of the employees with warts were unaware of them, particularly in regard to plane warts.

Adult↗

Consumption of charcoal-broiled meat as an experimental tool for discerning CYP1A2-mediated drug metabolism in vivo.

Cytochrome P450 1A2 (CYP1A2) is a major drug-metabolising enzyme. Polycyclic aromatic hydrocarbons, present in high concentrations in tobacco smoke and charcoal-broiled meat, are known to induce CYP1A2. The purpose of the present study was to validate enzyme induction by consumption of charcoal-broiled meat as an experimental tool for discerning CYP1A2-mediated drug metabolism in vivo. Twenty-four healthy, non-smoking men, all extensive metabolisers of sparteine (CYP2D6), participated in the study. All participants were genotyped for a putative CYP1A2-inducibility genotype. In the study diet period charcoal-broiled meat was served for lunch and dinner for five consecutive days. All participants were tested with probe reactions for CYP1A2 (caffeine) and CYP2C19 (proguanil) before and after consuming the study diet. Further, in three subgroups, they were tested with either the CYP1A2-substrate tacrine or probe reactions for CYP3A4 (quinidine) or CYP2C9 (tolbutamide). Neither probe reactions for CYP1A2, CYP2C9, CYP2C19 or CYP3A4 were affected by consumption of charcoal-broiled meat as practised in this study. No modifying role of the CYP1A2-inducibility genotype was evident. A number of experimental limitations are discussed, among them the lack of standardisation of exposure, the timing of phenotyping, and the choice of probe reactions. In conclusion, consumption of charcoal-broiled meat as practised in the present study appears not to be a useful experimental tool for discerning CYP1A2-mediated metabolism in vivo.

Adult↗

The excretion of urea by dogs following a meat meal.

1. After a meal of meat (10g/kg), urea excretion in dogs increased by about 200%, plasma urea by 60% and exogenous creatinine clearance by 40% in comparison with control experiments. 2. Urea, given by stomach tube in doses producing the same increase in plasma urea, caused urea excretion to increase by only 90%, with no increase in creatinine clearance. With the increased glomerular filtration rate after meat there was added excretion of urea. 3. In control experiments and after urea, the rate of excretion of urea was directly proportional to plasma urea. The ratio urea clearance/creatinine clearance, was 0-45. 4. After meat, urea clearance increased more than creatinine clearance, the ratio increasing to 0-55, i.e. a smaller fraction of the filtered urea was re-absorbed after meat. 5. After meat, 10g/kg, the rate of urea production rose to 230-600 mumole/min for 4-6 hr.

Animals↗

Sulphate excretion by dogs following ingestion of ammonium sulphate or meat.

1. When normal conscious dogs were given small doses of (NH4)2SO4 by stomach tube, the rate of excretion of SO4 increased due to increase in plasma SO4 without change in creatinine clearance. After eating meat, increased SO4 excretion was due to increase in glomerular filtration rate without change in plasma SO4. 2. The calculated rate of tubular reabsorption of SO4 did not change significantly either after (NH4)2SO4 or after meat. 3. The rate of production of SO4 after meat was estimated. In 4 hr approximately one fifth of the S in meat was converted to inorganic SO4; in the same time approximately one third of the N in the meat was converted into urea. 4. Half of the SO4 in the doses of (NH4)2SO4 was absorbed from the gut; all of the NH was converted into urea. (NH4)2SO4 thus produced acidosis. 5. After (NH4)2SO4, increased excretion of NH4+ accompanied the increased excretion of SO4-but Na+, K+ in urine also increased.

Absorption↗

Effects of nisin on growth of bacteria attached to meat.

Nisin had an inhibitory effect on gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, and Streptococcus lactis) but did not have an inhibitory effect on gram-negative bacteria (Serratia marcescens, Salmonella typhimurium, and Pseudomonas aeruginosa) attached to meat. Nisin delayed bacterial growth on meats which were artificially inoculated with L. monocytogenes or Staphylococcus aureus for at least 1 day at room temperature. If the incubation temperature was 5 degrees C, growth of L. monocytogenes was delayed for more than 2 weeks, and growth of Staphylococcus aureus did not occur. We also found that the extractable activity of nisin decreased rapidly when the meats were incubated at ambient temperatures and that this decrease was inversely related to the observed inhibitory effect. These findings disclosed that nisin delays the growth of some gram-positive bacteria attached to meat. However, nisin alone may not be sufficient to prevent meat spoilage because of the presence of gram-negative and other nisin-resistant gram-positive bacteria.

Animals↗

Role of osmolytes in adaptation of osmotically stressed and chill-stressed Listeria monocytogenes grown in liquid media and on processed meat surfaces.

Listeria monocytogenes is a food-borne pathogen that is widely distributed in nature and is found in many kinds of fresh and processed foods. The pervasiveness of this organism is due, in part, to its ability to tolerate environments with elevated osmolarity and reduced temperatures. Previously, we showed that L. monocytogenes adapts to osmotic and chill stress by transporting the osmolyte glycine betaine from the environment and accumulating it intracellularly (R. Ko, L. T. Smith, and G. M. Smith, J. Bacteriol. 176:426-431, 1994). In the present study, the influence of various environmental conditions on the accumulation of glycine betaine and another osmolyte, carnitine, was investigated. Carnitine was shown to confer both chill and osmotic tolerance to the pathogen but was less effective than glycine betaine. The absolute amount of each osmolyte accumulated by the cell was dependent on the temperature, the osmolarity of the medium, and the phase of growth of the culture. L. monocytogenes also accumulated high levels of osmolytes when grown on a variety of processed meats at reduced temperatures. However, the contribution of carnitine to the total intracellular osmolyte concentration was much greater in samples grown on meat than in those grown in liquid media. While the amount of each osmolyte in meat was less than 1 nmol/mg (fresh weight), the overall levels of osmolytes in L. monocytogenes grown on meat were about the same as those in liquid samples, from about 200 to 1,000 nmol/mg of cell protein for each osmolyte. This finding suggests that the accumulation of osmolytes is as important in the survival of L. monocytogenes in meat as it is in liquid media.

Adaptation, Physiological↗

Survival or growth of Escherichia coli O157:H7 in a model system of fresh meat decontamination runoff waste fluids and its resistance to subsequent lactic acid stress.

A potential may exist for survival of and resistance development by Escherichia coli O157:H7 in environmental niches of meat plants applying carcass decontamination interventions. This study evaluated (i) survival or growth of acid-adapted and nonadapted E. coli O157:H7 strain ATCC 43895 in acetic acid (pH 3.6 +/- 0.1) or in water (pH 7.2 +/- 0.2) fresh beef decontamination runoff fluids (washings) stored at 4, 10, 15, or 25 degrees C and (ii) resistance of cells recovered from the washings after 2 or 7 days of storage to a subsequent lactic acid (pH 3.5) stress. Corresponding cultures in sterile saline or in heat-sterilized water washings were used as controls. In acetic acid washings, acid-adapted cultures survived better than nonadapted cultures, with survival being greatest at 4 degrees C and lowest at 25 degrees C. The pathogen survived without growth in water washings at 4 and 10 degrees C, while it grew by 0.8 to 2.7 log cycles at 15 and 25 degrees C, and more in the absence of natural flora. E. coli O157:H7 cells habituated without growth in water washings at 4 or 10 degrees C were the most sensitive to pH 3.5, while cells grown in water washings at 15 or 25 degrees C were relatively the most resistant, irrespective of previous acid adaptation. Resistance to pH 3.5 of E. coli O157:H7 cells habituated in acetic acid washings for 7 days increased in the order 15 degrees C > 10 degrees C > 4 degrees C, while at 25 degrees C cells died off. These results indicate that growth inhibition by storage at low temperatures may be more important than competition by natural flora in inducing acid sensitization of E. coli O157:H7 in fresh meat environments. At ambient temperatures in meat plants, E. coli O157:H7 may grow to restore acid resistance, unless acid interventions are applied to inhibit growth and minimize survival of the pathogen. Acid-habituated E. coli O157:H7 at 10 to 15 degrees C may maintain a higher acid resistance than when acid habituated at 4 degrees C. These responses should be evaluated with fresh meat and may be useful for the optimization of decontamination programs and postdecontamination conditions of meat handling.

Acetic Acid↗

Survival of aerobic and anaerobic bacteria in chicken meat during freeze-dehydration, rehydration, and storage.

Total and anaerobic counts were ascertained on boneless, cooked, cubed, frozen chicken meat. We determined survival of aerobes and anaerobes in the natural flora after the meat was freeze-dehydrated and rehydrated at room temperature for 30 min and at 50, 85, and 100 C for 10 min. Total and anaerobic counts of bacteria in the rehydrated meat were established during storage of samples at 4, 22, and 37 C-until a spoilage odor was detected. Samples were also inoculated with Clostridium sporogenes and were dried and rehydrated at 100 C and stored at 37 C. Approximately 21% of the aerobes and 37% of the anaerobes survived drying and rehydration at room temperature. Many genera of aerobes, anaerobes, and facultative anaerobes survived drying and rehydration at 50 C; only sporeformers survived rehydration at 85 or 100 C. Low-temperature (4 C) storage of rehydrated meat produced ample shelf life (over 20 days), whereas storage at the higher temperature resulted in a shelf life of less than 30 hr. Approximately 81% of the C. sporogenes cells survived rehydration at 100 C and grew to over 10(7) cells within 40 hr. Our study presents additional data for adequate microbiological control in processing of freeze-dehydrated meat. Also, it points out the natural selection for sporeformers at high temperature of rehydration, stressing the need for consumer education in product handling for safety purposes.

Animals↗

Effect of nitrite and nitrate on toxin production by Clostridium botulinum and on nitrosamine formation in perishable canned comminuted cured meat.

Comminuted ham was formulated with different levels of sodium nitrite and nitrate, inoculated with Clostridium botulinum, and pasteurized to an internal temperature of 68.5 C. When added to the meat, nitrite concentrations decreased, and cooking had little effect on them. Nitrite concentrations decreased more rapidly during storage at 27 than at 7 C; however they remained rather constant at formulated levels throughout the experiment at both incubation temperatures. The level of nitrite added to the meat greatly influenced growth and toxin production of C. botulinum. The concentration of nitrite necessary to effect complete inhibition was dependent on the inoculum level. With 90 C. botulinum spores/g of meat, botulinum toxin developed in samples formulated with 150 but not with 200 mug of nitrite per g of meat. At a spore level of 5,000/g, toxin was detected in samples with 400 but not with 500 mug of nitrite per g of the product incubated at 27 C. At lower concentrations of nitrite, growth was retarded at both spore levels. No toxin developed in samples incubated at 7 C. Nitrate showed a statistically significant inhibitory effect at a given nitrite level; however, the effect was insufficient to be of practical value. Analyses for 14 volatile nitrosamines from samples made with varying levels of nitrite and nitrate were negative at a detection level of 0.01 mug of nitrite or nitrate per g of meat.

Animals↗

Effects of amplification facilitators on diagnostic PCR in the presence of blood, feces, and meat.

The full potential of diagnostic PCR is limited, in part, by the presence of inhibitors in complex biological samples that reduce the amplification efficiency. Therefore, different pre-PCR treatments are being used to reduce the effects of PCR inhibitors. The aim of the present study was to investigate the effects of 16 amplification facilitators to enhance DNA amplification in the presence of blood, feces, or meat. Different concentrations of amplification facilitators and inhibitory samples were added to PCR mixtures containing rTth or Taq DNA polymerase. The addition of 0.6% (wt/vol) bovine serum albumin to reaction mixtures containing Taq DNA polymerase reduced the inhibitory effect of blood and allowed DNA amplification in the presence of 2% instead of 0.2% (vol/vol) blood. Furthermore, the addition of bovine serum albumin (BSA) to reaction mixtures containing feces or meat enhanced the amplification capacities of both polymerases. Taq DNA polymerase was able to amplify DNA in the presence of 4% instead of 0.4% (vol/vol) feces and 4% instead of 0.2% (vol/vol) meat, and rTth was able to amplify DNA in the presence of 4% instead of 0.4% (vol/vol) feces and 20% instead of 2% (vol/vol) meat. The single-stranded DNA binding T4 gene 32 protein (gp32) had a relieving effect similar to that of BSA, except when it was added to PCR mixtures of rTth containing meat and of Taq DNA polymerase containing feces. The relieving effects of betaine and a cocktail of proteinase inhibitors were more sample specific. The addition of 11.7% (wt/vol) betaine allowed Taq DNA polymerase to amplify DNA in the presence of 2% (vol/vol) blood, while the addition of proteinase inhibitors allowed DNA amplification by both polymerases in the presence of 4% (vol/vol) feces. When various combinations of betaine, BSA, gp32, and proteinase inhibitors were tested, no synergistic or additive effects were observed. The effects of facilitators on real-time DNA synthesis instead of conventional PCR were also studied.

Blood↗