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Background Preoperative (neoadjuvant) chemotherapy and radiotherapy are more effective than similar postoperative treatment for oesophageal, gastric, and rectal cancers, perhaps because of more effective micrometastasis eradication and reduced risk of incomplete excision and tumour cell shedding during surgery. The FOxTROT trial aims to investigate the feasibility, safety, and efficacy of preoperative chemotherapy for colon cancer. Methods In the pilot stage of this randomised controlled trial, 150 patients with radiologically staged locally advanced (T3 with >= 5 mm invasion beyond the muscularis propria or T4) tumours from 35 UK centres were randomly assigned (2:1) to preoperative (three cycles of OxMdG [oxaliplatin 85 mg/m(2), l-folinic acid 175 mg, fluorouracil 400 mg/m(2) bolus, then 2400 mg/m(2) by 46 h infusion] repeated at 2-weekly intervals followed by surgery and a further nine cycles of OxMdG) or standard postoperative chemotherapy (12 cycles of OxMdG). Patients with KRAS wild-type tumours were randomly assigned (1:1) to receive panitumumab (6 mg/kg; every 2 weeks with the first 6 weeks of chemotherapy) or not. Treatment allocation was through a central randomisation service using a minimised randomisation procedure including age, radiological T and N stage, site of tumour, and presence of defunctioning colostomy as stratification variables. Primary outcome measures of the pilot phase were feasibility, safety, and tolerance of preoperative therapy, and accuracy of radiological staging. Analysis was by intention to treat. This trial is registered, number ISRCTN 87163246. Findings 96% (95 of 99) of patients started and 89% (85 of 95) completed preoperative chemotherapy with grade 3-4 gastrointestinal toxicity in 7% (seven of 94) of patients. All 99 tumours in the preoperative group were resected, with no significant differences in postoperative morbidity between the preoperative and control groups: 14% (14 of 99) versus 12% (six of 51) had complications prolonging hospital stay (p=0.81). 98% (50 of 51) of postoperative chemotherapy patients had T3 or more advanced tumours confirmed at post-resection pathology compared with 91% (90 of 99) of patients following preoperative chemotherapy (p=0.10). Preoperative therapy resulted in significant downstaging of TNM5 compared with the postoperative group (p=0.04), including two pathological complete responses, apical node involvement (1% [one of 98] vs 20% [ten of 50], p

The effect of abomasal fructo-oligosaccharides supplementation on sheep faecal microbiota was investigated in a balanced, two Latin square, cross-over design experiment. Ten fistulated sheep were managed in five consecutive periods, with each of five treatments (an ‘acidified saline’ control or one of four prebiotic candidates chosen to represent different types of oligosaccharides: Arabinogalactan, Fibruline, Raftilose, or Yacon) administered to two sheep in each period. Seven grams of fructo-oligosaccharides were used daily for each animal. In each period, fresh faecal samples were collected before, during and after ‘supplementation’ for the analysis of bifidobacteria, lactobacilli, Escherichia coli, sulphite-reducing clostridia, total anaerobes, pH and dry matter. The treatments with Fibruline, Raftilose and Yacon increased the sheep faecal bifidobacteria after 9 days of daily dosing. Compared with the control, the Raftilose treatment caused the greatest increase by 2.128 log10 CFU/g of faeces...

Aims: To identify the abattoir source(s) of psychrophilic clostridia causing ‘blown pack’ spoilage of vacuum-packed chilled meats. Methods and Results: Molecular procedures were used to detect the presence of specific 16S rRNA gene fragments of blown pack-causing clostridia in samples collected from a commercial abattoir and its environs. Blown pack-causing clostridia were consistently detected in hide, soil and faecal samples, as well as in samples collected at slaughter plant locations associated with handling of animals and animal carcasses prior to pelt removal. Conclusions: The data indicate that pelts per se or soil particles/faecal material attached thereto are the most probable primary reservoir of blown pack clostridia in the abattoir. Significance and Impact of the Study: The paper provides information critical for controlling blown pack spoilage in commercial meat-processing plants.

Aims: To develop a practical molecular procedure that directly, without isolation, and specifically detects the presence of clostridia which cause ‘blown pack’ spoilage of vacuum-packed meat. Methods and Results: Primer sets and PCR amplification procedures were developed that detect the presence of 16S rDNA gene and/or 16S-23S rDNA internal transcribed spacer fragments of ‘blown pack’ causing clostridia in meat. The specificity of the developed procedures was evaluated with DNA obtained from close phylogenetic neighbours of ‘blown pack’ causing clostridia, food clostridia and common meat spoilage microorganisms. The sensitivity of detection was assessed in non-enriched and low-temperature-enriched beef mince inoculated with serially diluted pure cultures of Clostridium estertheticum DSMZ 8809T and Cl. gasigenes DB1AT . The efficacy of detection procedures was evaluated for naturally contaminated vacuum-packed meat samples. Three primer sets, 16SE, 16SDB and EISR, produced amplicons of the expected size with DNA templates from target clostridia, but failed to yield PCR products with DNAs from any other microorganisms tested. With 16SE and 16SDB primers, minimum levels of detection were 104 CFU g−1 for non-enriched, and 102 CFU g−1 for enriched meat samples. Based on the established specificity of these primers, as well as DNA sequencing of amplicons, Cl. gasigenes was confirmed as the causative agent of ‘blown pack’ spoilage in two packs, and Cl. estertheticum as the causative agent in the third. Conclusions: The developed method can be used for rapid detection of ‘blown pack’ causing clostridia in commercial blown packs, or following low temperature enrichment, for detection of these microorganisms in meat containing as few as 100 clostridial cells per gram. Significance and Impact of the Study: The paper reports practical procedures that can be used for rapid confirmation of the causative agents of clostridial ‘blown pack’ spoilage in commercial spoiled packs, or for detection of psychrophilic clostridia in epidemiological trace back of ‘blown pack’ spoilage incidents in meat processing plants.

Aims: To identify the abattoir source(s) of culturable psychrophilic clostridia causing ‘blown pack’ spoilage of vacuum-packed chilled meats. Methods and Results: Psychrophilic and psychrotolerant clostridia were isolated from hides, faeces and tonsils of deer slaughter stock, and from a meat plant environment. The isolates were differentiated using restriction fragment length polymorphism analysis of the 16S rDNA gene (PCR–RFLP) and 16S-23S rDNA internal transcribed spacer (ITS) analysis. PCR–RFLP group I clostridia were found to have restriction patterns indistinguishable from the patterns of ‘blown pack’-causing Clostridium gasigenes DB1AT and R26. Gas production in packs inoculated with vegetative cells of PCR–RFLP group I clostridia was first evident after 14 days at 2 °C. The prevalence of these clostridia was similar in hide and faecal samples from slaughter animals, but these micro-organisms were absent from tonsils and the meat plant environment. Banding patterns of PCR–RFLP group II clostridia showed some cross-similarity with patterns of the ‘blown pack’-causing micro-organism Cl. estertheticum DSM 8809T and Cl. estertheticum-like meat strains. The majority of clostridia in PCR–RFLP group II were found in the faeces of slaughter animals. Isolates representing PCR–RFLP group II did not, however, produce gas in vacuum packs stored at 2 °C for 84 days. Conclusions: The data suggest that soil particles attached to hide or present in faeces are the most probable primary reservoir from which ‘blown pack’ clostridia are introduced onto carcasses. Therefore, dressing procedure hygiene remains paramount in order to control the spread of psychrophilic Clostridium spp. in a meat plant. Significance and Impact of the Study: The paper provides information critical for controlling ‘blown pack’ spoilage in meat processing plants. It reports on the use of molecular techniques for determination of abattoir sources of ‘blown pack’-causing clostridia.

Aims: To develop a practical molecular procedure that directly (without isolation) and specifically detects the presence of clostridia, which cause the deep tissue spoilage condition . Methods and Results: A primer set was designed and a PCR amplification procedure developed to detect the presence of Clostridium algidicarnis and Cl. putrefaciens 16S rDNA gene fragments in meat. The procedure yielded amplicons of the expected size with homologous DNA templates, but failed to give PCR products with DNAs from 47 food clostridia and common meat spoilage micro-organisms. The minimum level of detection was 104 cfu g−1 for nonenriched meat samples. Based on the established specificity of these primers, as well as DNA sequencing of amplicons, the presence of Cl. algidicarnis and/or Cl. putrefaciens was confirmed in a swab sample taken from the cartilage of an ovine stifle joint, which on opening exhibited strong offensive odours. Conclusions: The developed method can be used for rapid detection of clostridia causing deep tissue spoilage in commercial vacuum packs. Significance and Impact of the Study: The paper reports practical procedures that can be used for rapid confirmation of the causative agents of deep tissue clostridial spoilage in commercial vacuum-packed chilled meats.

This study was undertaken to determine if carbon dioxide packaging of meat afforded a food safety advantage over vacuum packaging with respect to botulinal toxin production during chilled storage. A cocktail of washed spores from five toxigenic clostridial strains - four reference Clostridium botulinum strains [types A, B (2 strains) and E] and a C. butyricum type E strain - was inoculated onto lamb chumps. Of these strains, two were psychrotolerant. The inoculated chumps were individually carbon dioxide packaged and duplicate packs were placed into storage at 10, 8, 6, 4 and 2C. All storage regimens included a weekly defrost cycle when meat surface temperatures increased by up to 6 to 7C during a 2 to 2.5 h period. After 84 days storage, packs were assessed for the presence of botulinal toxin using the mouse bioassay procedure. All packs contained botulinal toxin. To compare toxin production in vacuum and carbon dioxide packs at chill temperatures, the challenge trials were repeated for 4 and 2C storage. Packs were examined at regular intervals for toxin presence. Both pack types contained toxin after 21 and 48 days storage at 4 and 2C, respectively. In the unlikely, but not impossible, event that raw meat would be contaminated with psychrotolerant toxin-capable clostridial spores, product safety, with respect to botulinal toxin presence after prolonged chilled storage, requires storage temperatures to be maintained below 2C for both vacuum and carbon dioxide packaged product.

Isolates (259) of psychrotrophic Clostridium spp. associated with either blown pack spoilage (five isolates) or slaughter stock (254 isolates) were screened for the presence of botulinum neurotoxin (BoNT) genes using degenerate PCR primers capable of amplifying A, B, E, F and G BoNT genes. No BoNT gene amplification products were detected using DNA templates from the 259 psychrotrophic isolates, including 249 isolates that showed the same 16S rRNA gene Restriction Fragment Length Polymorphism (RFLP) patterns as authentic Cl. botulinum type B. It is concluded that although the growth of such micro-organisms in vacuum-packed chilled meat leads to product spoilage, it does not prejudice product safety.

Low-frequency, seasonal variations in sea level and sea-surface temperature (SST) for the north-east coast of the North Island, New Zealand were investigated using mainly multivariate analyses in the frequency domain over a 20-year period (1973–92). The dominant influence on the annual cycle of sea level (mean amplitude=378 mm) is associated with thermo-steric sea-level adjustments, which explains 50–80% of the variance in the annual frequency band. Sea levels generally peak at the end of April (austral autumn), lagging the SST cycle by around 2 months. The inclusion of secondary forcing variables (barometric pressure and alongshore wind stress) in the multivariate analysis increases the proportion of the variance explained to 70–90+%. Thermo-steric adjustments in sea level almost completely mask the inverted-barometer effect at annual and longer timescales. The response of sea level to wind stress (alongshore) is also anticorrelated to its response to barometric pressure, thereby appearing to reduce the magnitude of the barometric factor below 10 mm hPa−1. These latter factors, along with changes in oceanic current patterns and seasonal coupling of El Nino–Southern Oscillation effects, cause secondary effects on seasonal sea-level variability.

Aerobic and anaerobic plate counts were compared for routine monitoring of the microflora, dominated by lactic acid bacteria, developing on vacuum- and carbon dioxide-packaged raw meat during chilled storage. No statistical differences were observed between aerobic and anaerobic enumerations, made on plate count and blood agar plates, of the microflora developing on beef striploins packaged under vacuum or carbon dioxide during 14 weeks' storage at 0 degree C. With both techniques the spoilage microflora development differed between the two packaging regimes. The results indicate that there is no necessity for aerobic plate counts to be replaced by anaerobic plate counts in the routine microbiological examination of the spoilage microflora developing on chilled meats packaged under anoxic modified atmospheres.

Three beef dressing lines of different capacity (160, 440 and 800 head d(-1)) were investigated with respect to contamination associated with carcass/hide and carcass/faeces contacts, the distribution of microbial contamination on carcasses and the antimicrobial efficacy of cold water carcass washes. Swab samples were taken from up to 17 sites for determination of Aerobic Plate Counts at 37 degrees C (APC 37 degrees C) and Escherichia coli enumeration using the Petrifilm procedure. The three beef dressing systems produced virtually identical patterns of microbial contamination. High contamination was found at those sites associated with opening cuts and/or subject to hide contact during hide removal. Where contamination is intermittent, the use of mean microbial data tended to obscure evidence of faecal or hide contact. Consequently, worst-case results, as represented by the 95th percentile value, were used to identify probable instances and sources of contact contamination. Sites not subject to faecal contamination or hide contact typically had swab sample APC (37 degrees C) values of less than log 2.00 cfu cm(-2) accompanied by the occasional detection of E. coli at levels below log 1.00 cfu cm(-2). Sites contacted by 'clean' hide typically had APC (37 degrees C) counts of log 3.00 cfu cm(-2) or greater accompanied by occasional E. coli counts not exceeding log 2.00 cfu cm(-2). Sites contaminated by direct faecal contact or contact with faecally contaminated hides typically had APC (37 degrees C) counts equal to, or greater than, log 4.00 cfu cm(-2) accompanied by E. coli counts exceeding log 2.00 cfu cm(-2). Cold water carcass washing was ineffective in removing microbial contamination and tended to bring about a posterior to anterior redistribution, resulting in increased counts at forequarter sites.

Process pasteurization values for reference temperature 70 degrees C (P70) were calculated from the temperature profiles of 250 g luncheon meat chubs cooked under experimental conditions. A simple equation relating Process P70-value and the time and temperature of cooking was derived. With minimal cooking (P70 = 40) the surviving microflora (10(3)/g) wad dominated by species of Lactobacillus, Brochothrix and Micrococcus. These organisms were destroyed by more intensive cooking (P70 = 105), leaving a flora (10(2)/g) composed of Bacillus and Micrococcus species. The spoilage that developed after 14 d storage at 25 degrees C reflected the severity of the heat treatment received by each chub: with P70 between 40 and 90, a Streptococcus spoilage sequence occurred; with P70 between 105 and 120, a Bacillus/Streptococcus spoilage sequence occurred; with P70 of 135 and above, a Bacillus spoilage sequence occurred. Cooking to a P70 = 75 was adequate to reduce the surviving microflora to the 10(2)/g level associated with current good manufacturing practice.

Summary The antibody-dependent cell-mediated larvicidal response of AO rats against Trichinella spiralis newborn larvae was studied in vivo. Rats were immunized with 2000-3000 muscle larvae orally and then challenged 6-20 days later with 10 000-20 000 newborn larvae intraperitoneally. Newborn larvae recovery from the peritoneal cavity decreased significantly and was accompanied by cuticular cell adherence and killing of newborn larvae by day 9 of infection. Similar effects were observed when newborn larvae were incubated with blood obtained from immunized rats. The cell adherence and larvicidal responses reached their peak by day 16 of the primary infection. Passive transfer experiments demonstrated that newborn larvae infectivity was substantially impaired once cell adherence occurred. Culicular adherence took place in vitro only when immune serum was added to the incubation medium. Complete destruction of newborn larvae in vivo after passive transfer, as measured by muscle larvae burden was only evident after exposure to both immune serum and immune cells, not to either alone. Non-specific stimulation of the peritoneal cavity with a sterile intestinal infection failed to induce cuticular adherence or larval killing in these rats. We conclude that a stage-specific antibody-dependent cell-mediated larvicidal response is rapidly generated in vivo after the host is exposed to newborn larvae. It is a systemic response which impairs the infectivity of newborn larvae and can destroy them before they reach muscle tissue.

A pour plate procedure employing 10 plates at each of 2 dilutions was used to determine the Aerobic Plate Count of bacteria in tropical surface water. The counts were conducted on 3 water samples at each of the following incubation temperatures: 20, 25, 30, 35 and 40°C. Colonies appearing on the plates were counted after 24, 48, 72, 96 and 120 h incubation. Following statistical analysis ( P = 0.05) of the results it is recommended that 30°C for 72 h be adopted as a standard incubation regime for Aerobic Plate Counts of bacteria in warm tropical waters.

The shelf life at 25°C of chub-packed luncheon meat was inversely related to oxygen (O2) availability within the casing. With fibrous casings that are freely permeable to O2, shelf life was less than 3 d. With plastic casings of low O2 permeability, the shelf life was 7 d when air was trapped in the emulsion during the casing filling process, 14 d when air was not trapped (normal vacuum-stuffing) and greater than 28 d when vacuum-stuffed chubs were stored in hydrogen (H2). The initial spoilage bacteria, Bacillus spp., grew only at the surface unless air was trapped in the emulsion when growth occurred throughout the luncheon meat. Bacillus spp. failed to grow on luncheon meat stored under H2. Oxygen availability within the casing determined both the site and rate of microbial spoilage of chub-packed luncheon meat.

The effect of salt (NaCl) on the efficacy of nisin in preventing outgrowth of Bacillus licheniformis spores was determined in Plate Count Agar (PCA). An equivalent liquid medium was used for heat activation. Nisin and salt were added to the heat-activation medium, the PCA, or both. The spores were extremely sensitive to nisin; outgrowth were completely inhibited in salt-free media when 10 iu/ml of nisin was present in both the heat-activation and the growth media or when 100 iu/ml nisin was present in either the heat-activation and the growth medium. In media supplemented with 1% salt, outgrowth occurred from 1% of spores exposed to 100 iu/ml nisin in either the heat-activation or the growth medium. A 3% salt supplement was necessary before detectable outgrowth occurred when both the heat-activation and the growth media contained 100 iu/ml nisin. Salt appears to antagonize the sporicidal action of nisin by interfering with nisin adsorption onto the spore.

The fecal coliform populations of raw sewage, sewage lagoon effluent, and river water were determined using the most probable number technique. The total coliphage populations of the three water sources were determined using Escherichia coli B (ATCC 11303-1) host cells. The ratios of fecal coliforms to coliphage in the three water samples were 87:1, 4.2:1, and 0.15:1, respectively. The ratio of fecal coliforms to coliphage in stored raw sewage decreased from 87:1 to about 1:1 within 7 days at 20°C and within 28 days at 4°C. These changing ratios resulted from the greater longevity of the coliphage compared with that of the coliform bacteria. The use of the ratio of fecal coliforms to coliphage is not considered reliable as an index of when a fecal pollution event occurred because the ratio is influenced by prior contamination, presence of sediment, chlorination, and temperature.

Freshly cooked luncheon meat in a plastic (PVDC) casing had an aerobic plate count of about 102/g. The flora was composed of approximately equal numbers of Bacillus and Micrococcus spp. Storage at 10°C for 42 d produced little increase in bacterial numbers, or changes in pH value or glucose content at either the surface or core of the luncheon meat. Storage at 25°C allowed Bacillus spp. to proliferate at the surface. The inhibitory effect of salt and nitrite on the growth of heated Bacillus spores at low redox potentials probably accounts for the absence of growth within the product. Growth at the surface was accompanied by a fall in pH (6.8 to 6.2) and an increase in glucose (1.6 to 3.6 mg/g) and L(+)-lactic acid (1.2 to 2.3 mg/g). By day 14 the Bacillus spp. had been displaced by a Streptococcus sp. (107/g) which remained the dominant organism until the experiment ended on day 28. The pH continued to fall from 5.7 on day 14 to 5.2 on day 28, the L(+)-lactic acid rose to 6.1 mg/g, but the glucose remained constant at the day 7 level (3.6 mg/g). This indicates that glucose converted to lactic acid was largely replaced by hydrolysis of the starch portion of the luncheon meat mediated by amylases produced by the Bacillus microflora. It appears that growth of the Streptococcus is dependent upon the denitrifying activities of the initial Bacillus flora reducing the concentration of nitrite ion to non-inhibitory levels.