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Biomedical subjects

Z Matyás

Publications and source records attributed to Z Matyás.

At least 19 recordsLinked to original sources
PubMed1992

The state of food hygiene and foodborne diseases: requirements for the future.

The current world situation of foodborne diseases is reviewed with an analysis of the factors responsible for their occurrence in both developed and developing countries. Strategies to solve the problems associated with food hygiene are also reviewed with special attention to the most recent approaches identified and worked out by the main institutions concerned. Specific suggestions are given for more effective planning and implementation of future global food hygiene programmes.

Developing Countries↗
PubMed1992

[Epidemiologic aspects of a new approach to monitoring hygienic food handling using the hazard analysis critical control points (HACCP) system].

The hitherto used traditional control of food hygiene focused on assessment whether the controlled sanitary and technological practice is consistent with requirements of regulations sometimes comprises also details of minor importance. To put it briefly, in the course of the production process are many check-up points, but only some or possibly only one is a critical control point. Moreover, by periodic supervision the hygienist is able to record the hygienic and technological state typical only for the time of control. Microbiological examination of final products can reveal only negative sequelae of microbial processes; it does not provide information on the conditions of contamination nor ensure protection against it. For these and other reasons the conclusion is reached that the hitherto used traditional approach of the hygiene supervision is not quite effective and must be replaced by a more active approach focused on the control of factors threatening the wholesomeness already during the production process. The new approach to supervision of food hygiene is the HACCP system (hazard analysis critical control points). The system works rationally as it is based on analysis of systematically assembled data on the causes and conditions which evoked the illness of the consumers by food products or meals. HACCP can be described as prompt, as health or quality problems are revealed immediately after their genesis during production or processing and are eliminated immediately. The system is also comprehensive as it comprises not only the basic technological process incl. processing or modification of ingredients but takes into account also the handling of the given food product after termination of production and in particular final culinar processing. The system can be applied to all pathogenic agents transmitted by foods to man from bacteria and their toxins, viruses, parasites, moulds and mycotoxins, biotoxins but also contaminants and radionuclides. The system requires reliable epidemiological statistics of alimentary infections and intoxications and in practice the participation of an epidemiologist, hygienist and food technologist.

Food Handling↗
PubMed1991

[The effects of some technologies on survival of Campylobacter jejuni in food of animal origin].

The effects of some technologies (cooling, freezing, salting, packaging, fermentation, cold smoking, heat treatment) on the survival of Campylobacter jejuni were investigated. The different technological procedures can be considered as barriers influencing to a certain degree the survival of C. jejuni. The low value aw on the surface of chilled meat and oxygen presence reduce the occurrence of C. jejuni, but the low storage temperature prolongs the survival of C. jejuni to two days. In chilled poultry the high relative water content is combined with the low temperature and C. jejuni is able to survive even for five days. In the freezing process the low temperature has only partial effects on C. jejuni devitalization; C. jejuni can survive in this case for two to eight weeks. The survival of C. jejuni is prolonged considerably by packaging: six to seven days in polyethylene sheet, 10 days in vacuum packing and 10 to 13 days in gas packing (80% N2 and 20% CO2). NaCl can partly devitalize C. jejuni, and in comminuted meant it survives for five to seven days. In the non-precooked meat products (TNMV) and with the minimally fortnight time of ripening a number of barriers play their role which are destroying C. jejuni (aw, pH, antagonistic microflora). Due to these barriers C. jejuni was isolated in these products maximally for seven days. In this type of products with short durability (two to three days) the action of barriers is limited, that means C. jejuni could be demonstrated for two to six days.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

The gnotobiotic piglet as a model for the pathogenesis of Campylobacter jejuni infection.

The pathogenesis of enteric changes was studied in gnotobiotic piglets which, after hysterectomy had been infected orally with Campylobacter jejuni on the first day of their life. The involvement of the entire large intestine became clinically manifest by scouring on days post infection (DPI) 4 to DPI 5, and pathomorphologically, by simultaneous inflammation and severe edema of the intestinal wall. Histology and SEM revealed inflammatory edema with abundant neutrophils, microulcerations, focal propagation and activation of goblet cells, and a presence of mucin-positive material within the intestinal lumen. TEM examination revealed disconnected interdigitating folds and wide dilated intercellular spaces between enterocytes. The endothelial cells of small blood vessels in the lamina propria showed hypertrophy with increase in the thickness of their basal lamina. Ultrastructural lesions of the large intestinal microcirculation also support the hypothesis that disturbances in the vascular system are responsible for edema in the cecum and colon. Gnotobiotic piglets may be used as a suitable animal model to study colitis induced by C. jejuni.

Animals↗
PubMed1989

[Dynamics of Campylobacter jejuni invasion in gnotobiotic piglets].

The study deals with the results of the investigation of C. jejuni populations in the intestines of gnotobiotic piglets after oral infection with C. jejuni in the span of one to five days after infection (DAI). The infection of the whole large intestine was revealed, with the onset of pathological lesions 3rd DAI. C. jejuni was isolated from liver, gallbladder, ileum, rectum, colon, mesenterial lymphatic node, rectal smears and blood. From 1st to 5th DAI C. jejuni was demonstrated in liver, gallbladder and posterior part of ileum. In the cecum and rectum C. jejuni was detected as late as on 2nd-3rd DAI to 5th DAI and in mesenterial lymphatic nodes from 2nd to 4th DAI. In rectal smears C. jejuni was found out regularly during the whole period of experiment. C. jejuni was also isolated from inflammatory infiltrate. Histological examination revealed C. jejuni between the villi and in the contents of cup-shaped cells from 2nd to 5th DAI.

Animals↗
PubMed1987

[Campylobacter jejuni and its incidence in meat packaged under warm conditions].

The problem of survival of Campylobacter jejuni was studied in artificially contaminated butchered meat packed in warm condition. Apart from the presence of Campylobacter jejuni, the total number of microorganisms and the shelf life of the meat were studied. With plain packing, Campylobacter jejuni survived six to seven days and the shelf life of the meat was about a week. In vacuum-packed meat Campylobacter jejuni was isolated for ten to eleven days and sensory changes occurred after ten to fourteen days. In meat packed in protective atmosphere Campylobacter jejuni was able to survive for ten to thirteen days and the meat kept its sensory properties for a fortnight or longer. There were no differences in the survival of Campylobacter jejuni in pork and beef, nor were there any substantial differences in the microorganism survival in PSE, DFD meat and in intact meat.

Animals↗
PubMed1983

[Study of the presence of sterigmatocystin in Czechoslovak grain].

Owing to its carcinogenic, hepatotoxic, nephrotoxic and dermatotoxic action, sterigmatocystine belongs to risky substances. Grains should be therefore examined for its content. A detailed description of a simple method for a current examination of grains for sterigmatocystine content is given and the method is recommended. Seventy-four samples were examined (24 samples of wheat, 19 samples of barley, 16 samples of maize, 10 samples of oats and 5 samples of rye) coming from the South Moravian, West Slovakian and East Slovakian regions from the 1980 and 1981 harvests. Only two barley samples and two maize samples were found to be positive: the maize samples contained about 50 micrograms and the samples of barley 200 and 400 micrograms of sterigmatocystine per 1 kg. One sample of wheat had a trace amount of the substance.

Czechoslovakia↗
PubMed1983

[Characteristics of the meat of cattle with cysticercosis due to experimental infection with the eggs of the tapeworm Taenia saginata and treated with praziquantel].

Eleven test and control bullocks of the Bohemian Spotted breed were studied for the effect of cysticercosis and their treatment with praziquantel on the properties of meat and fat. As found, the disease affected the composition of meat and fat and some of the studied characteristics and technological properties of meat. Although the measles disappeared after treatment, they were not resorbed. Therefore, irrespective of the worsened meat quality, the meat and organs of such animals cannot be evaluated in any other way but according to the valid veterinary regulations.

Animals↗
PubMed1982

[Detection of T-2 toxin in grains using thin layer chromatography with silica gel (TLC)].

The TLC method of the detection of T-2 toxin in grains is described. A thin layer of silica gel with a sensitivity of 3 mg/kg is used in this method. In comparison with the biological assay for dermal irritability, the TLC method is 30 times less sensitive. However, it has one great advantage over the bioassay: its specificity. It is recommended for practice to use a screening method based on the test for the dermal irritability of rabbits. When the content of toxins is higher, the analytic method can be used for trying to identify the given mycotoxin of the trichothecene group. T-2 toxin was detected in none of the 33 samples of tested grains (14 samples of barley, 7 wheat, 5 rye, 5 oats, 2 samples of maize).

Chromatography, Thin Layer↗
PubMed1982

[Biological assay for trichothecenes in grain].

Three different extract preparation procedures were used to produce the extracts to be applied to the skin of rabbits. In this way one hundred samples of the grains (wheat - 35, barley - 31, maize - 10, rye - 10, oats - 14) originating from the South Moravian, West Slovakian and East Slovakian regions were tested. These samples were taken from the 1980 crop which grew under climatic conditions extremely suitable for the growth of fusaria and the production of mycotoxins. Out of one hundred tested samples only five (5%) had a toxic effect on the rabbit skin. Out of these five samples only three (3%) contained T-2 toxin at the amount of 1 mg . kg-1 (two barley samples) and 0.1 mg . kg-1 (one barley sample) when examined semiquantitatively. The dermal changes evoked by two other samples were caused by other mycotoxins of the trichothecene group because the phenomenon typical of T-2 toxin (stronger skin reaction after 48 hrs than after 24 hrs after application) was not observed. The described method is recommended for screening examination of the grains for the presence of trichothecene mycotoxins.

Animal Feed↗
PubMed1982

[Study of cheeses for the presence of sterigmatocystin].

Sixty-six samples of hard cheeses (Edam Block, Edam Cake, Svĕtlan, Moravian Block, Emmenthal), taken from retail shops, were examined by the chromatographic method using thin silica-gel layer. Three samples were positive. It was demonstrated by semiquantitative examination that two samples of Edam Cake contained 7.5 and 17.5 micrograms of sterigmatocystine in kg and one sample of Moravian Block contained 7.5 micrograms/kg. The described method is very simple and is recommended to be used by food-control institutions for the practical examination of cheese for the presence of sterigmatocystine.

Cheese↗
PubMed1981

[The occurrence of zearalenone in domestic grains].

The occurrence of zearalenone had not been tested n Czechoslovakia; out of a number of analytic procedures for the determination of this mycotoxin in grains and some feed mixtures, the method described by Mirocha et al. (1974) was chosen for this study. The tests were performed with 61 samples of grain and 22 samples of other feeds. In barley 58.3% of the samples were positive in the range from 0.19 to 0.82 micromol.kg-1 in wheat 46.4% of samples in the range from 0.19 to 0.57 micromol. kg-1, in maize 6.7% of samples, containing 0.33 mumol.kg-1. Oat samples contained no zearalenone. The positive findings in the samples of the commercial mixtures COS 1, COS 2, SOL and KPB ranged from 0.19 to 0.32 mumol. kg-1. Zearalenone concentrations above 0.32 mumol. kg-1 were found in seven samples of wheat, in four samples of barley, in one sample of maize and in one sample of complete feed mixture for early-weaned piglets. The described method is recommended for screening examination of grains for zearalenone in Czechoslovakia.

Animal Feed↗
PubMed1981

[The effect of fattening of swine using grape cake on carcass characteristics and meat quality].

Fattened pigs were given standard diet containing 10% of crushed cake from white or red grapes. The replacement of part of the diet by this material was not found to exert any adverse influence on the health of the animals, evaluated according to slaughter characteristics. In most of the studied characteristics of the carcass and meat the difference between the control and experimental animals was not statistically significant and the meat of the animals had satisfactory nutritional and technological properties. The use of both kinds of grape cake resulted in the production of carcasses with a higher percentage of lean meat. The experimental animals also had a higher proportion of essential fatty acids in intramuscular fat.

Adipose Tissue↗
PubMed1981

[The effect of Ridzol P used in pig fattening on carcass characteristics and meat quality].

The meat and fat of slaughter pigs given diet with Ridzol P (60 mg per kg of feed) were studied. During the veterinary examination the additive was not found to have any adverse effect on the health of the animals. Judging from the studied meat and fat characteristics, there were no significant differences in the nutritive and technological value of the meat of the pigs given feed with Ridzol P, as compared with the controls. The additive was found to have a good influence on significantly higher weight of the cut lean parts. Hardly any difference was found in the proportions of the fatty acids of intramuscular fat, back fat and flare fat.

Adipose Tissue↗
PubMed1981

[Analysis of aflatoxin Ml in fresh milk].

Seventy-seven samples of cow's milk were examined by the method after Stubble-field (1979) for the presence fo aflatoxin M1; 34 of these samples came directly from farms and 43 were mixed, being taken from tank trucks. Aflatoxin M1 was found in five samples from farms and in none of the mixed samples. In the positive cases, concentrations were determined semiquantitatively and were found to range from a trace amount up to 0.38 microgram aflatoxin M1 per litre of milk. Hence the aflatoxin M1 concentration levels never exceeded tha admissible limit value.

Aflatoxin M1↗
PubMed1981

[The effect of adding dried pig feces to the diet of egg-laying hens on the quality of eggs].

Eggs from two groups of layers (eight hens in each group) were subjected to examination. The hens were given diet with pig dried faeces at a concentration of 2.5% and 5% for six months and at a concentration of 5% and 10% for another five months. The organoleptic examination of the eggs and determination of some chemical characteristics of yolks and albumins did not reveal any systematic deviations of their properties in comparison with the eggs from the hens of the control group. This did not suggest that pig faeces added to hen diet as a feed component might have a negative effect on egg quality.

Animal Feed↗