Longer resistance of some DNA traits from BT176 maize to gastric juice from gastrointestinal affected patients.

The presence of antibiotic resistance marker genes in genetically engineered plants is one of the most controversial issues related to Genetically Modified Organism (GMO)-containing food, raising concern about the possibility that these markers could increase the pool of antibiotic resistance genes. This study investigates the in vitro survival of genes bla and cryIA(b) of maize Bt176 in human gastric juice samples. Five samples of gastric juice were collected from patients affected by gastro-esophageal reflux or celiac disease and three additional samples were obtained by pH modification with NaHCO3. DNA was extracted from maize Bt176 and incubated with samples of gastric juices at different times. The survival of the target traits (bla gene, whole 1914 bp gene cry1A(b), and its 211 bp fragment) was determined using PCR. The stability of the target genes was an inverse function of their lengths in all the samples. Survival in samples from untreated subjects was below the normal physiological time of gastric digestion. On the contrary, survival time in samples from patients under anti-acid drug treatment or in samples whose pH was modified, resulted strongly increased. Our data indicate the possibility that in particular cases the survival time could be so delayed that, as a consequence, some traits of DNA could reach the intestine. In general, this aspect must be considered for vulnerable consumers (people suffering from gastrointestinal diseases related to altered digestive functionality, physiological problems or drug side-effects) in the risk analysis usually referred to healthy subjects.

Melaleuca alternifolia essential oil possesses potent anti-staphylococcal activity extended to strains resistant to antibiotics.

Melaleuca alternifolia Cheel essential oil (TTO) and its major component terpinen-4-ol were examined against a large number of clinical isolates of Staphylococcus aureus to establish their anti-staphylococcal activities. Classic and established procedures were used to study M.I.C., time-kill curves, synergism and mutational frequency. The anti-staphylococcal activity of terpinen-4-ol and TTO were superior to those of antibiotics belonging to the major families (all the tested drugs are for topical use or included in ointments, eye drops or used during surgery); terpinen 4-ol and TTO were active against strains resistant to mupirocin, fusidic acid, vancomycin, methicillin and linezolid. TTO and terpinen-4-ol were bactericidal as revealed by time-kill curves; the frequency of mutational frequency to TTO was < 2.9 x 10 9. The study demonstrates good anti-staphylococcal activity of TTO and terpinen-4-ol against a large number of S.aureus isolates and suggests the possible application of these agents for topical treatment of staphylococcal infections. This is the first extensive study on the anti-staphylococcal activity of TTO. The results suggest that this compound may have application as a topical agent for the control of superficial staphylococcal infections, including activity against organisms resistant to antibiotics which can be used, or are specific, for topical use.

Combined Plate Microbial Assay (CPMA): a 6-plate-method for simultaneous first and second level screening of antibacterial residues in meat.

This paper proposes an improved high throughput microbial method for the simultaneous performance of first and second level screening for antibacterial residues in meat. It is based on growth inhibition of B. subtilis on agar medium pH 6, 7.2 and 8, of B. cereus on agar medium pH 5.9, of M. luteus on agar medium pH 8 and of E. coli on agar medium pH 7.2 (research or first level screening) and on the use of confirmatory solutions (Pase, Paba, MgSO4) for the identification or second level screening. In kidney control samples, dialysis membranes were interposed between samples and the agar surface to both prevent the action of lysozyme and reduce false positive results. The proposed method detects beta-lactams, sulfonamides, tetracyclines, aminoglycosides, macrolides and quinolones at MRL concentrations and reliably indicates the inhibitor family. Results are obtained in 18-24 h.

Antimycotic activity of Melaleuca alternifolia essential oil and its major components.

AIMS: The aim of this study was to analyse the antimycotic properties of Melaleuca alternifolia essential oil (tea tree oil, TTO) and its principal components and to compare them with the activity of 5-fluorocytosine and amphotericin B. METHODS AND RESULTS: The screening for the antimycotic activity was performed by serial twofold dilutions in Roswell Park Memorial Institute medium with the inclusion of Tween-80 (0.5%). TTO and terpinen-4-olo were the most active compounds. CONCLUSIONS: The majority of the organisms were sensitive to the essential oil, with TTO and terpinen-4-olo being the most active oils showing antifungal activity at minimum inhibitory concentration values lower than other drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a sample large enough to determine the antifungal properties of TTO and terpinen-4-olo and suggests further studies for a possible therapeutic use.

Clostridium botulinum spores and toxin in mascarpone cheese and other milk products.

A total of 1,017 mascarpone cheese samples, collected at retail, were analyzed for Clostridium botulinum spores and toxin, aerobic mesophilic spore counts, as well as pH, a(w) (water activity), and Eh (oxidation-reduction potential). In addition 260 samples from other dairy products were also analyzed for spores and botulinum toxin. Experiments were carried out on naturally and artificially contaminated mascarpone to investigate the influence of different temperature conditions on toxin production by C. botulinum. Three hundred and thirty-one samples (32.5%) of mascarpone were positive for botulinal spores, and 7 (0.8%) of the 878 samples produced at the plant involved in an outbreak of foodborne botulism also contained toxin type A. The chemical-physical parameters (pH, a(w), Eh) of all samples were compatible with C. botulinum growth and toxinogenesis. Of the other milk products, 2.7% were positive for C. botulinum spores. Growth and toxin formation occurred in naturally and experimentally contaminated mascarpone samples after 3 and 4 days of incubation at 28 degrees C, respectively.

A case of infant botulism associated with honey feeding in Italy.

A case of infant botulism in a 9 week-old female is described. A strain of C. botulinum type B was isolated from the feces of the baby. The epidemiologic study detected in a sample of home canned honey Clostridium botulinum spores of the same serotype that was isolated from the patient. The honey had been used only to sweeten the pacifier of the baby. This is the first case of infant botulism in Europe linked conclusively to honey.

Presence of tobramycin in kidneys and placentae of Sprague-Dawley rat fetuses and newborns following in utero exposure.

The maternal-fetal transfer of tobramycin (TBM) was investigated in the rat by means of a microbiological assay, to assess the presence and amount in the kidneys and placentae of fetuses at gestational day (GD) 20, in the kidneys of newborns 6 and 11 days after the end of treatment and in the kidneys of the dams. In the qualitative assay, pregnant rats were injected i.p. with 0, 30, 60 mg/kg b.w. of TBM on GD 10-19. A group of dams treated in parallel with 30 mg/kg b.w. was utilized for a microbiological semiquantitative assay. All litters contained some fetuses showing no detectable TBM accumulation in either kidney or in placentae: at 30 mg/kg/b.w. accumulation appeared more prevalent in placenta than in the kidneys of the corresponding fetuses, as confirmed also by the semiquantitative assay. Some newborns (about 6%) of both groups showed detectable renal TBM residues on the 6th and on the 11th day after the end of treatment. The frequency of newborns showing residues was not obviously related to the dose or the day of sampling, and the concentrations of TBM found were comparable to those observed in fetuses. It is possible that they represent a particularly sensitive subgroup.

Wound botulism: clinical and microbiological findings of an Italian case.

A case of wound botulism in a 41-year old man is reported. The patient had accidently been wounded when he fell on an iron bar. Some days later he developed typical clinical manifestations of botulism. Wound botulism was confirmed by detection and quantification of type B botulinal toxin in the serum. Ventilatory supportive care was necessary and botulinal antitoxin was not given. The patient was hospitalized for 30 days and recovery was complete.

Kinetics of excretion in milk of some antimastitis drugs.

A study on the kinetics of excretion in milk of some antimastitis drugs is described. The five antibiotic molecules used were detected by confronting two methods: the Galesloot-Hassing method which, even though specific for the detection of penicillin in milk, is officially used for the detection of antibiotic residues in general; and the M. luteus paper disk assay, which uses M. luteus ATCC 9341 as test microorganism. The obtained results show that withdrawal times for the assayed molecules are longer than those declared and that M. luteus is more efficient for the detection of kanamycin residues.

[Food poisoning caused by Clostridium botulinum type E]. / Intossicazione alimentare da Clostridium botulinum tipo E.

The results of a microbiological investigation carried out into a home-canned tuna fish are reported in relation to a suspected botulism case. Toxin of Cl. botulinum type E was detected by mouse toxicity and neutralization tests. The food specimen were also cultured for Cl. botulinum. The isolates was identified as Cl. botulinum type E by biochemical, gas chromatographic and immunological tests. The outbreak in which for the first time in Italy, the Cl. botulinum type E is involved, concerns one person who showed typical signs and symptoms consistent with botulism (abdominal cramps, dilatated pupils, diplopia, dysphagia, paralysis of lower upper limbs). The laboratory results are discussed with relation to environmental characteristics of the micro-organism and their resistance to same chemical and physical factors with are involved in the canning practice.

Riboflavin status among rural children in Southern Italy.

A sample of 107 boys aged 7-10 in a rural area of Southern Italy was studied for riboflavin deficiency and its association with milk consumption. The boys represented 74 per cent of the total male population of that age group in the study area. The nutritional status was assessed by means of anthropometric indicators, dietary intakes by a 24-h recall method and the riboflavin status was evaluated by the assay of erythrocyte glutathione reductase activity. The nutritional status was found to be generally satisfactory with about one tenth of the children presenting stunting, wasting, or obesity. This picture is comparable to that recorded at the national level. The overall incidence of biochemical riboflavin deficiency was 13 per cent. No clinical sign of riboflavin deficiency was observed. None of the anthropometric indicators of malnutrition appeared to be related to biochemical evidence of riboflavin malnutrition. Dietary data showed that the children consumed a relatively small amount of milk and dairy products (mean 224 +/- 109 g/d). Thirteen out of 14 children with biochemical evidence of riboflavin deficiency belonged to the group who consumed less than 300 g/d of milk. However, only 15 per cent of the children consuming less than 300 g/d of milk and dairy products had biochemical evidence of riboflavin deficiency. It appears that the dietary pattern in rural areas with traditionally low milk consumption is compatible with a relatively satisfactory riboflavin nutriture. This finding suggests that milk and dairy products may occupy, under different dietary practices, a role less critical than usually attributed.

Nutrition, environment and physical performance of preschool children in Italy.

While overt malnutrition is known to interfere with several bodily functions and to cause a deterioration of the level of physical performance, little or no information is available on the effect of marginal nutrition on functional development, particularly at earlier ages. A cross-sectional study of the diet, somatic development and functional response to exercise of 2,241 children, aged 1-6 years, representing contrasting socioeconomic environments, has been carried out. The findings indicate that the upper socioeconomic urban child from Central Italy consumes a better diet and is larger than the underprivileged Southern child. While a greater proportion of the latter group experience a considerable degree of growth retardation, the better efficiency of their heart responses to exercise indicates that the level of nutrition of these children is still good enough to be compatible with a more satisfactory degree of physical fitness. The body fat content and skinfold thickness of the child from the Center have found to be significantly higher than those of the children from the poorer sections of the population, suggesting that at least part of the extra energy available to him for physical activity is being deposited as fat. This raises the question of the desirability of changes in somatic development characteristic of upward social mobility, when accompanied by increased adiposity without a proportional increase in the functional capacity.