Safety Assessment of Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA Determined in Trials with Wistar Rats.

Colonization of Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA in the gastro-intestinal tract was determined by using Wistar rats as model. The strains were administered through intragastric gavage over 14 days. FISH with strain-specific oligonucleotide probes indicated that Lact. plantarum 423 adhered to the surfaces of the ileum and the cecum. Enterococcus mundtii ST4SA, on the other hand, adhered to the surfaces of the cecum and colon. Results obtained by DGGE have shown that strains 423 and ST4SA excluded Enterobacteriaceae, but not lactic acid bacteria, from the cecum and colon. No signs of perforation of epithelial cells by strains 423 and ST4SA were detected. The spleen and liver appeared healthy and blood counts were normal, suggesting that the strains are not pathogenic. Both strains produce antimicrobial peptides active against a number of pathogens and may be considered as probiotics.

Expression of the Mucus Adhesion Gene Mub, Surface Layer Protein Slp and Adhesion-Like Factor EF-TU of Lactobacillus acidophilus ATCC 4356 Under Digestive Stress Conditions, as Monitored with Real-Time PCR.

Expression of the mucus adhesion gene Mub, surface layer protein Slp and adhesion-like factor EF-Tu by Lactobacillus acidophilus ATCC 4356 grown in the presence of mucin, bile and pancreatin and at low pH was studied using real-time PCR. None of the genes were up-regulated under increasing concentrations of mucin, while Slp and EF-Tu were up-regulated in the presence of bile and pancreatin at normal concentrations (0.3%, w/v) and under stress conditions (1.0%, w/v).

Expression of the mucus adhesion genes Mub and MapA, adhesion-like factor EF-Tu and bacteriocin gene plaA of Lactobacillus plantarum 423, monitored with real-time PCR.

Expression of the mucus adhesion genes Mub and MapA, adhesion-like factor EF-Tu and bacteriocin gene plaA by Lactobacillus plantarum 423, grown in the presence of bile, pancreatin and at low pH, was studied by real-time PCR. Mub, MapA and EF-Tu were up-regulated in the presence of mucus, proportional to increasing concentrations. Expression of MapA was up-regulated in the presence of 3.0 g/l bile and 3.0 g/l pancreatin at pH 6.5. Similar results were recorded in the presence of 10.0 g/l bile and 10.0 g/l pancreatin at pH 6.5. Expression of Mub was down-regulated in the presence of bile and pancreatin, whilst the expression of EF-Tu and plaA remained unchanged. Expression of Mub and MapA remained unchanged at pH 4.0, whilst expression of EF-Tu and plaA were up-regulated. Expression of MapA was down-regulated in the presence of 1.0 g/l l-cysteine HCl, suggesting that the gene is regulated by transcription attenuation that involves cysteine.

Markers of hepatitis B in nurses and domestic staff in an area of high endemicity.

Results obtained in two sero-epidemiologic surveys of hospital personnel in Durban were collated to yield information on 423 nurses and 141 domestic staff. The prevalence of antibodies to HBV was 14.9 per cent in 101 white nurses, 52.5 per cent in 322 African nurses and 51.8 per cent in 141 African domestics. This represents a greater than eight times increase for white nurses and a 50 per cent increase for African nurses and domestics over that seen in the equivalent blood donor groups (P less than 0.001 in each case). Antibody prevalence increased with age for all three staff groups, as did the number of individuals exhibiting a marker pattern (HBcAb greater than HBsAb) suggestive of persisting infection. No white nurses but 14 (4.3 per cent) African nurses and 17 (12.1 per cent) African domestics were HBsAg positive, the antigenaemia in domestics representing a significant increase (P less than 0.001) over the 4.0 per cent seen in female African blood donors. Six of the nurses and two of the domestics were also HBeAg positive. African nurses in adult medical wards showed greatest exposure (57 per cent) closely followed by nurses working in outpatient departments (54 per cent) and as theatre staff (52 per cent). Lower exposure rates (40 per cent) were seen in paediatric and renal unit nurses. This contrasts with results obtained for doctors in the two surveys which indicated that while Indian and white doctors are at significantly higher risk in the African hospital, African doctors are not, and that doctors working in surgical and renal departments are at higher risk than doctors on adult medical wards.(ABSTRACT TRUNCATED AT 250 WORDS)