Animal board invited review: Specialising and intensifying cattle production for better efficiency and less global warming: contrasting results for milk and meat co-production at different scales.

Cattle are the world's largest consumers of plant biomass. Digestion of this biomass by ruminants generates high methane emissions that affect global warming. In the last decades, the specialisation of cattle breeds and livestock systems towards either milk or meat has increased the milk production of dairy cows and the carcass weight of slaughtered cattle. At the animal level and farm level, improved animal performance decreases feed use and greenhouse gas emissions per kg of milk or carcass weight, mainly through a dilution of maintenance requirements per unit of product. However, increasing milk production per dairy cow reduces meat production from the dairy sector, as there are fewer dairy cows. More beef cows are then required if one wants to maintain the same meat production level at country scale. Meat produced from the dairy herd has a better feed efficiency (less feed required per kg of carcass weight) and emits less methane than the meat produced by the cow-calf systems, because the intake of lactating cows is largely for milk production and marginally for meat, whereas the intake of beef cows is entirely for meat. Consequently, the benefits of breed specialisation assessed at the animal level and farm level may not hold when milk and meat productions are considered together. Any change in the milk-to-meat production ratio at the country level affects the numbers of beef cows required to produce meat. At the world scale, a broad diversity in feed efficiencies of cattle products is observed. Where both productions of milk per dairy cow and meat per head of cattle are low, the relationship between milk and meat efficiencies is positive. Improved management practices (feed, reproduction, health) increase the feed efficiency of both products. Where milk and meat productivities are high, a trade-off between feed efficiencies of milk and meat can be observed in relation to the share of meat produced in either the dairy sector or the beef sector. As a result, in developing countries, increasing productivities of both dairy and beef cattle herds will increase milk and meat efficiencies, reduce land use and decrease methane emissions. In other regions of the world, increasing meat production from young animals produced by dairy cows is probably a better option to reduce feed use for an unchanged milk-to-meat production ratio.

Inactivation of Cryptosporidium parvum oocysts and faecal indicator bacteria in cattle slurry by addition of ammonia.

AIMS: To determine inactivation of Cryptosporidium parvum oocysts and reduction of Escherichia coli and enterococci in cattle slurry added aqueous ammonia. METHODS AND RESULTS: Escherichia coli, enterococci and nonviable C. parvum oocysts (DAPI+PI+) were enumerated every second day for 2 weeks in cattle slurry amended with 60 mmol l-1 aq. ammonia and compared with untreated slurry at three temperatures. Regardless of temperature, the proportion of nonviable C. parvum oocysts increased significantly faster over time in slurry with added ammonia than raw slurry (P = 0·021) corresponding to 62·0% higher inactivation (P = 0·001) at day 14. Additionally, 91·8% fewer E. coli and 27·3% fewer enterococci were observed in slurry added ammonia at day 14 compared to raw slurry. CONCLUSION: The addition of aqueous ammonia to raw slurry significantly reduced the viability of C. parvum oocysts and numbers of bacterial indicators. Hence, ammonia is usable at lower pathogen concentrations in slurry before application to agricultural land. SIGNIFICANCE AND IMPACT OF THE STUDY: Livestock waste is a valuable source of plant nutrients and organic matter, but may contain high concentrations of pathogens like E. coli and Cryptosporidium sp. that can be spread in the environment, and cause disease outbreaks. However, die-off rates of pathogens in organic waste can increase following increasing ammonia concentrations.

A 6-month randomized, double-blind, placebo-controlled trial of weekly exenatide in adolescents with obesity.

BACKGROUND: Pharmacological treatment options for adolescents with obesity are very limited. Glucagon-like-peptide-1 (GLP-1) receptor agonist could be a treatment option for adolescent obesity. OBJECTIVE: To investigate the effect of exenatide extended release on body mass index (BMI)-SDS as primary outcome, and glucose metabolism, cardiometabolic risk factors, liver steatosis, and other BMI metrics as secondary outcomes, and its safety and tolerability in adolescents with obesity. METHODS: Six-month, randomized, double-blinded, parallel, placebo-controlled clinical trial in patients (n = 44, 10-18 years, females n = 22) with BMI-SDS > 2.0 or age-adapted-BMI > 30 kg/m2 according to WHO were included. Patients received lifestyle intervention and were randomized to exenatide extended release 2 mg (n = 22) or placebo (n = 22) subcutaneous injections given once weekly. Oral glucose tolerance tests (OGTT) were conducted at the beginning and end of the intervention. RESULTS: Exenatide reduced (P < .05) BMI-SDS (-0.09; -0.18, 0.00), % BMI 95th percentile (-2.9%; -5.4, -0.3), weight (-3 kg; -5.8, -0.1), waist circumference (-3.2 cm; -5.8, -0.7), subcutaneous adipose tissue (-552 cm3 ; -989, -114), 2-hour-glucose during OGTT (-15.3 mg/dL; -27.5, -3.1), total cholesterol (11.6 mg/dL; -21.7, -1.5), and BMI (-0.83 kg/m2 ; -1.68, 0.01) without significant change in liver fat content (-1.36; -3.12, 0.4; P = .06) in comparison to placebo. Safety and tolerability profiles were comparable to placebo with the exception of mild adverse events being more frequent in exenatide-treated patients. CONCLUSIONS: Treatment of adolescents with severe obesity with extended-release exenatide is generally well tolerated and leads to a modest reduction in BMI metrics and improvement in glucose tolerance and cholesterol. The study indicates that the treatment provides additional beneficial effects beyond BMI reduction for the patient group.

Phase II multicentre trial of oral quisinostat, a histone deacetylase inhibitor, in patients with previously treated stage IB-IVA mycosis fungoides/Sézary syndrome.

BACKGROUND: Quisinostat is a hydroxamate, second-generation, orally available pan-histone deacetylase inhibitor. OBJECTIVES: To evaluate the efficacy and safety of oral quisinostat in patients with previously treated cutaneous T-cell lymphoma (CTCL). METHODS: Patients received quisinostat 8 mg or 12 mg on days 1, 3 and 5 of each week in 21-day treatment cycles. Primary efficacy end point was cutaneous response rate (RR) based on the modified Severity Weighted Assessment Tool (mSWAT). Secondary end points included global RR, duration of response (DOR) in skin, progression-free survival (PFS), pruritus relief, safety and pharmacodynamic markers. RESULTS: Eight of 26 (25 evaluable) patients achieved ≥ 50% reduction in mSWAT score at least once, with confirmed cutaneous response in six (RR 24%). There was a low global RR of 8%. DOR in skin ranged from 2·8 to 6·9 months. Median PFS was 5·1 months. Pruritus relief was more frequent in cutaneous responders (67%) than nonresponders (32%). Serial tumour biopsies revealed an increase in acetylated tubulin, indicating a target effect of histone deacetylase 6. Twenty-one of 26 (81%) patients were withdrawn from the study before or at clinical cut-off; five (19%) continued to receive treatment with quisinostat. The most common drug-related adverse events were nausea, diarrhoea, asthenia, hypertension, thrombocytopenia and vomiting. Grade 3 drug-related adverse events included hypertension, lethargy, pruritus, chills, hyperkalaemia and pyrexia. CONCLUSIONS: Quisinostat 12 mg three times weekly is active in the treatment of patients with relapsed or refractory CTCL, with an acceptable safety profile. Combination therapy with other drugs active in CTCL may be appropriate.

Children with cerebral palsy do not achieve healthy physical activity levels.

AIM: This study compared daily activity energy expenditure (AEE) in children with cerebral palsy with a control group and investigated whether the children achieved healthy levels of physical activity. METHODS: We enrolled eight children with bilateral cerebral palsy, from eight to 10 years of age, and a group of controls matched for age and gender. For three days, physical activity was simultaneously measured by accelerometers and self-reports using a diary. The daily AEE results were compared between groups and methods. The number of children that achieved healthy physical activity levels in each group was explored. RESULTS: Children with cerebral palsy had significantly lower daily AEE, as measured by accelerometers, than the controls, and they did not achieve the healthy moderate to heavy physical activity level defined in the Nordic Nutrition Recommendations. Self-reports using the diaries resulted in an overestimation of physical activity compared with the ankle accelerometer measurements in both groups. CONCLUSION: Our investigation of physical activity in children with cerebral palsy and controls using accelerometers and a diary found low levels of daily AEE and physical activity, and these results were most prominent in the group with cerebral palsy. The diaries overestimated physical activity in both groups.

Isotope dilution ESI-LC-MS/MS for quantification of free and total Nε-(1-Carboxymethyl)-L-Lysine and free Nε-(1-Carboxyethyl)-L-Lysine: comparison of total Nε-(1-Carboxymethyl)-L-Lysine levels measured with new method to ELISA assay in gruel samples.

ESI-LC-MS/MS method with isotope dilution and SPE based on cation-exchange was developed for determination of free and total Nε-(1-Carboxymethyl)-L-Lysine (CML) and free Nε-(1-Carboxyethyl)-L-Lysine (CEL). The use of nonafluoropentanoic acid in mobile phase was omitted, SPE recoveries of 82±3% and 91±10% (n=6) for CML and CEL respectively and, calibration curves (R(2)>0.9985) were attained. The method was applied to gruel samples and LoQ for the method was 5 ng/ml, RSD <10% and accuracy was 115%. Total CML levels in the gruel samples varied from 103-408 mg/kg protein. Free CML levels which were 1000 times lower than total CML were three times higher than free CEL levels. CML in a gruel sample was 127±7, 84±9 and 253±28 mg/kg using the current ESI-LC-MS/MS, ELISA and GC-MS respectively. The described method has advantages over ELISA with respect to reproducibility and specificity and over GC-MS with respect to reproducibility.

Escherichia coli contamination of lettuce grown in soils amended with animal slurry.

A pilot study was conducted to assess the transfer of Escherichia coli from animal slurry fertilizer to lettuce, with E. coli serving as an indicator of fecal contamination and as an indicator for potential bacterial enteric pathogens. Animal slurry was applied as fertilizer to three Danish agricultural fields prior to the planting of lettuce seedlings. At harvest, leaves (25 g) of 10 lettuce heads were pooled into one sample unit (n = 147). Soil samples (100 g) were collected from one field before slurry application and four times during the growth period (n = 75). E. coli was enumerated in slurry, soil, and lettuce on 3M Petrifilm Select E. coli Count Plates containing 16 mg/liter streptomycin, 16 mg/liter ampicillin, or no antimicrobial agent. Selected E. coli isolates (n = 83) originating from the slurry, soil, and lettuce were genotyped by pulsed-field gel electrophoresis (PFGE) to determine the similarity of isolates. The slurry applied to the fields contained 3.0 to 4.5 log CFU/g E. coli. E. coli was found in 36 to 54% of the lettuce samples, streptomycin-resistant E. coli was found in 10.0 to 18.0% of the lettuce samples, and ampicillin-resistant E. coli in 0 to 2.0% of the lettuce samples (the detection limit was 1 log CFU/g). The concentration of E. coli exceeded 2 log CFU/g in 19.0% of the lettuce samples. No E. coli was detected in the soil before the slurry was applied, but after, E. coli was present until the last sampling day (harvest), when 10 of 15 soil samples contained E. coli. A relatively higher frequency of E. coli in lettuce compared with the soil samples at harvest suggests environmental sources of fecal contamination, e.g., wildlife. The higher frequency was supported by the finding of 21 different PFGE types among the E. coli isolates, with only a few common PFGE types between slurry, soil, and lettuce. The frequent finding of fecal-contaminated lettuce indicates that human pathogens such as Salmonella and Campylobacter can be present and represent food safety hazards.

Escherichia coli contamination and health aspects of soil and tomatoes (Solanum lycopersicum L.) subsurface drip irrigated with on-site treated domestic wastewater.

Faecal contamination of soil and tomatoes irrigated by sprinkler as well as surface and subsurface drip irrigation with treated domestic wastewater were compared in 2007 and 2008 at experimental sites in Crete and Italy. Wastewater was treated by Membrane Bio Reactor (MBR) technology, gravel filtration or UV-treatment before used for irrigation. Irrigation water, soil and tomato samples were collected during two cropping seasons and enumerated for the faecal indicator bacterium Escherichia coli and helminth eggs. The study found elevated levels of E. coli in irrigation water (mean: Italy 1753 cell forming unit (cfu) per 100 ml and Crete 488 cfu per 100 ml) and low concentrations of E. coli in soil (mean: Italy 95 cfu g(-1) and Crete 33 cfu g(-1)). Only two out of 84 tomato samples in Crete contained E. coli (mean: 2700 cfu g(-1)) while tomatoes from Italy were free of E. coli. No helminth eggs were found in the irrigation water or on the tomatoes from Crete. Two tomato samples out of 36 from Italy were contaminated by helminth eggs (mean: 0.18 eggs g(-1)) and had been irrigated with treated wastewater and tap water, respectively. Pulsed Field Gel Electrophoresis DNA fingerprints of E. coli collected during 2008 showed no identical pattern between water and soil isolates which indicates contribution from other environmental sources with E. coli, e.g. wildlife. A quantitative microbial risk assessment (QMRA) model with Monte Carlo simulations adopted by the World Health Organization (WHO) found the use of tap water and treated wastewater to be associated with risks that exceed permissible limits as proposed by the WHO (1.0 × 10(-3) disease risk per person per year) for the accidental ingestion of irrigated soil by farmers (Crete: 0.67 pppy and Italy: 1.0 pppy). The QMRA found that the consumption of tomatoes in Italy was deemed to be safe while permissible limits were exceeded in Crete (1.0 pppy). Overall the quality of tomatoes was safe for human consumption since the disease risk found on Crete was based on only two contaminated tomato samples. It is a fundamental limitation of the WHO QMRA model that it is not based on actual pathogen numbers, but rather on numbers of E. coli converted to estimated pathogen numbers, since it is widely accepted that there is poor correlation between E. coli and viral and parasite pathogens. Our findings also stress the importance of the external environment, typically wildlife, as sources of faecal contamination.

Physical capacity, respiratory quotient and energy expenditure during exercise in male patients with schizophrenia compared with healthy controls.

BACKGROUND: Despite massive research on weight gain and metabolic complications in schizophrenia there are few studies on energy expenditure and no current data on physical capacity. AIM: To determine oxygen uptake capacity, respiratory quotient (RQ) and energy expenditure during a submaximal exercise test in patients with schizophrenia and healthy controls. METHOD: Ten male patients and 10 controls were included. RQ and energy expenditure were investigated with indirect calorimetry during a cycle ergometer test. The submaximal work level was defined by heart rate and perceived exhaustion. Physical capacity was determined from predicted maximal oxygen uptake capacity (VO(2-max)). RESULTS: The patients exhibited significantly higher RQ on submaximal workloads and lower physical capacity. A significant lower calculated VO(2-max) remained after correction for body weight and fat free mass (FFM). Energy expenditure did not differ on fixed workloads. CONCLUSION: RQ was rapidly increasing in the patients during exercise indicating a faster transition to carbohydrate oxidation and anaerobic metabolism that also implies a performance closer to maximal oxygen uptake even at submaximal loads. This may restrict the capacity for everyday activity and exercise and thus contribute to the risk for weight gain. Physical capacity was consequently significantly lower in the patients.

Microbiological assessments of compost toilets: in situ measurements and laboratory studies on the survival of fecal microbial indicators using sentinel chambers.

Compost toilet systems were assessed for their ability to reduce microbial indicators and pathogens. Bacterial pathogens were not detected in any samples indicating a low survival rate in composting feces and/or an initial low occurrence. Indicator bacteria showed large variations with no clear trend of lower bacterial numbers after longer storage. In controlled composting experiments, thermophilic conditions were only reached when amendments were made (grass and a sugar solution). Even then it was impossible to ensure a homogenous temperature in the composting fecal material and therefore difficult to achieve a uniform reduction and killing of indicator organisms. Presumptive thermotolerant coliforms, Salmonella typhimurium Phage 28 B and eggs of Ascaridia galli, proved useful as indicators. However, regrowth was detected for enterococci and total numbers of bacteria grown at 36 degrees C. These indicator parameters may therefore overestimate the level of other (pathogenic) bacteria present in the material and can not be recommended for use as reliable indicator organisms in composting toilet systems. The addition of indicator bacteria to fecal material contained in semi-permeable capsules proved to be a useful technique to ensure that microorganisms were contained in a small test volume.

Increased lipolysis in LCHAD deficiency.

An increasing number of fatty acid oxidation defects are being detected owing to diagnostic improvements and a greater awareness among clinicians. The metabolic block leads to energy disruption, fatty infiltration, and toxic effects on organ functions exerted by beta-oxidation metabolites. This investigation was undertaken to assess the influence of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency on lipolysis and energy turnover. We addressed the question whether the lipolysis and glucose production rates would be altered in the fasting state in a child with this disease. Lipolysis, glucose production and resting energy expenditure (REE) were studied in a 17-month-old girl with LCHAD deficiency and her healthy twin sister. Lipolysis and glucose production were determined after a 4-6 h fast by constant-rate infusion of [1,1,2,3,3-(2)H(5)]glycerol and [6,6-(2)H(2)]glucose and analysis by gas chromatography-mass spectrometry. REE was estimated by indirect calorimetry. The affected girl showed 50% higher lipolysis than did her sister, whereas the glucose production rates were similar. Plasma levels of dicarboxylic acids of 6-12 carbon atoms chain length, 3-hydroxy fatty acids of 6-18 carbon atoms chain length, total free fatty acids, and acylcarnitines were increased in the patient, as was REE. Since glucose production rates and plasma glucose levels were similar in the two girls, the increased lipolysis observed in the patient probably represents a compensatory mechanism for energy generation. This is achieved at the price of an augmented risk for fatty acid infiltration and toxic effects of beta-oxidation intermediates. This highlights the importance of avoiding fasting in these patients.

Differences in resting energy expenditure and body composition between patients with schizophrenia and healthy controls.

OBJECTIVE: A lowered energy metabolism in schizophrenia was reported already in the 1920s. However, these early investigations were case studies without control groups or statistical analysis. In this study the resting energy expenditure (REE) and relevant body composition variables were measured in patients with schizophrenia and healthy controls. METHOD: REE was determined in 30 patients and 17 controls. The difference between the measured and the expected level for each individual was calculated as DeltaREE. Body composition was assessed with bioelectrical impedance and calliper measurements. RESULTS: DeltaREE was significantly lower in the patients than in the controls. A decrease was also seen in the non-medicated patients. The patients showed significantly lower percentages of water in fat free-mass and intracellular water. CONCLUSION: The lowering of REE and body water fractions may suggest a homeostatic aberration in schizophrenia that may be of importance for the understanding of metabolic disturbances observed in the disease.

Dissemination of vancomycin-resistant enterococci harboring vanA through disposal of waste derived from industrial production of vancomycin.

We demonstrated the occurrence of vancomycin-resistant enterococci (VRE) in waste derived from the industrial production of vancomycin and their dissemination through disposal of such waste into a sewage treatment plant. Bacteriological counts on a medium selective for enterococci (Slanetz-Bartley agar) revealed the presence of high numbers of presumptive VRE (approximately 10(6) CFU/ml) in the waste originating from the fermentation biomass used for vancomycin production. The waste was also found to contain active residues of vancomycin (64-1,024 microg/ml) by bioassays using a vancomycin-susceptible enterococcal strain. Randomly amplified polymorphic DNA (RAPD) analysis of 65 presumptive VRE isolates from the waste allowed distinction of four genotypes, two of which (A and D) belonged to the genus Enterococcus, most likely E. faecium, and harbored the vanA gene conferring high-level vancomycin resistance. The same VRE strains found in the waste occurred also in the biological tanks and the final effluent of the sewage treatment plant receiving the waste, as demonstrated by the detection of undistinguishable pulsed-field gel electrophoresis (PFGE) patterns in VRE isolated from these sources. These results indicate the need to assess the possible dissemination of VRE and other antibiotic-resistant bacteria through disposal of waste derived from antibiotic production.

Vibrio cholerae O1 outbreak isolates in Mozambique and South Africa in 1998 are multiple-drug resistant, contain the SXT element and the aadA2 gene located on class 1 integrons.

The characteristics of Vibrio cholerae O1 biotype El Tor, serotype Ogawa isolates from outbreaks of cholera in 1998 amongst migrant workers in the South African provinces of Gauteng and Mpumalanga, on the border of Mozambique, are reported. The isolates seem to have originated from the same clone since they are of two closely related BglI ribotypes. These ribotypes had a high similarity to ribotypes of V. cholerae O1 recently found in three South-east Asian countries. Isolates were resistant to furazolidone, streptomycin, sulfamethoxazole, trimethoprim and tetracycline. Only two isolates contained plasmids of 54 and 63 kb in size. PCR and DNA sequencing revealed that the chromosomally located resistance determinants present included an aadA2 gene cassette contained in a class 1 integron; the SXT element, which is a transposon-like element containing resistance genes; and the tetA gene. A co-transfer of chromosomal closely located genes encoding the SXT element and tetA was shown by mating experiments, PCR and pulsed-field gel electrophoresis analyses. Our study shows for the first time that multiple-resistant V. cholerae O1 isolates containing class 1 integrons and the SXT element were responsible for cholera outbreaks in Southern Africa. Studies are needed to determine the spread of this multiple-resistant O1 strain and further genetic details of the association of the SXT element, tetA and class 1 integrons, including their means of transfer.

Clinical and environmental isolates of Vibrio cholerae serogroup O141 carry the CTX phage and the genes encoding the toxin-coregulated pili.

We report sporadic cases of a severe gastroenteritis associated with Vibrio cholerae serogroup O141. Like O1 and O139 serogroup strains of V. cholerae isolated from cholera cases, the O141 clinical isolates carry DNA sequences that hybridize to cholera toxin (CT) gene probes. The CT genes of O1 and O139 strains are carried by a filamentous bacteriophage (termed CTX phage) which is known to use toxin-coregulated pili (TCP) as its receptor. In an effort to understand the mechanism of emergence of toxigenic O141 V. cholerae, we probed a collection of O141 clinical and environmental isolates for genes involved in TCP production, toxigenicity, virulence regulation, and other phylogenetic markers. The collection included strains isolated between 1964 and 1995 from diverse geographical locations, including eight countries and five U.S. states. Information collected about the clinical and environmental sources of these isolates suggests that they had no epidemiological association. All clinical O141 isolates hybridized to probes specific for genes encoding CT (ctx), zonula occludens toxin (zot), repetitive sequence 1 (RS1), RTX toxin (rtxA), the major subunit of TCP (tcpA), and the essential regulatory gene that controls expression of both CT and TCP (toxR). In contrast, all but one of the nonclinical O141 isolates were negative for ctx, zot, RS1, and tcpA, although these strains were positive for rtxA and toxR. The one toxigenic environmental O141 isolate was also positive for tcpA. Ribotyping and CT typing showed that the O141 clinical isolates were indistinguishable or closely related, while a toxigenic water isolate from Louisiana showed a distantly related ribotype. Nonclinical O141 isolates displayed a variety of unrelated ribotypes. These data support a model for emergence of toxigenic O141 that involves acquisition of the CTX phage sometime after these strains had acquired the pathogenicity island encoding TCP. The clonal nature of toxigenic O141 strains isolated from diverse geographical locations suggests that the emergence is a rare event but that once it occurs, toxigenic O141 strains are capable of regional and perhaps even global dissemination. This study stresses the importance of monitoring V. cholerae non-O1, non-O139 serogroup strains for their virulence gene content as a means of assessing their epidemic potential.

Serum anti-p53 in relation to mutations across the entire translated p53 gene in colorectal carcinomas.

Previous reports have claimed that antibodies to mutated p53 protein indicate poor outcome in malignant disease. The mechanism behind this highly specific process is unclear, although it has been claimed that certain DNA alterations are prone to induction of immune response, since wild-type p53 is almost never immunogenic. The aim of the present analysis was to evaluate whether the presence of anti-p53 was statistically significantly related to any certain DNA alterations in the entirely expressed p53 gene in primary tumors of colorectal cancer. P53 serum antibodies were determined by an enzyme linked immunosorbant assay (ELISA). P53 antibodies were detected in serum of 24 of 88 patients (27%). Twenty-two of 24 (92%) sero-positive patients had mutations in their p53 gene while only 22 of 64 (34%) sero-negative patients had p53 mutations (p<0.01). Mutations were mainly missense with a trend to significantly higher frequency of deletions in sero-negative patients compared to sero-positive subjects (8/25, 32% and 2/22, 9% respectively, p<0.08). Mutations in sero-positive patients were mainly located in exon 5 and 7 and within conserved regions (17 of 22 mutations). In sero-negative patients missense mutations were usually located in exon 5, 7 and 8 being also most frequently located within conserved regions. Most of the p53 deletions in sero-negative patients were however located outside conserved regions (seven of eight deletions). There was no statistical difference between sero-positive and negative patients concerning the spectrum of mutations along the expressed gene. Our study demonstrates that p53 antibodies are usually related to p53 gene mutations but a mutational event is not sufficient to elicit self-immunization. Cellular protein binding to p53 or individual differences of major histocompatibility complex based presentation of p53 protein sequences by immune cells is therefore the most likely explanation between sero-negative and sero-positive patients.

Mutations and allelic loss of p53 in primary tumor DNA from potentially cured patients with colorectal carcinoma.

PURPOSE: To compare p53 alterations in survivors and nonsurvivors after surgery for colorectal cancer. PATIENTS AND METHODS: Twenty-nine potentially cured patients with colorectal carcinoma, without recurrent disease for more than 6 years after their primary surgery, were selected to match a group of 41 colorectal cancer patients with early metastatic spread to the liver. All patients were screened for mutations in the p53 gene, exons 5 to 9, by denaturing gradient gel electrophoresis and subsequent sequencing. RESULTS: The frequency of p53 mutations was significantly different in cured patients (60%) compared with patients with early relapse (41%, P <.05). A significant difference was found in the distribution of mutations, indicating that potentially cured patients had a different proportion of mutations in conserved regions of p53 (P =.02). This difference was explained by a significantly different frequency of mutations in exon 8 (40% v 15%, P =.03), which is part of the conserved region V. All mutations in region V were codon 273 mutations in cured patients, whereas three of four mutations were located in codon 273 in patients with metastatic disease. Allelic loss of p53 (loss of heterozygosity [LOH]) was demonstrated in 26% of the cured patients and in 39% of patients with metastatic disease (P =.36). The combination of mutation and LOH of p53 was the same (17%) in both groups. CONCLUSION: A large number of p53 mutations in colorectal cancer do not promote disease progression. Some mutations, particularly within conserved regions, may even counteract negative functional effects of other p53 structural alterations. A complete loss of p53 function was not related to survival or progression after curative operation of colorectal carcinoma.

P53 mutations in primary tumors and subsequent liver metastases are related to survival in patients with colorectal carcinoma who undergo liver resection.

BACKGROUND: The appearance of p53 mutations in colorectal carcinoma was determined, independent of differentiation and tumor stage of the primary tumors, in relation to the survival of patients who were scheduled to undergo liver resection. METHODS: Tumor material was analyzed for p53 mutations in primary colorectal tumors and subsequent liver metastases from 41 consecutive patients who were scheduled to undergo surgical liver resection. DNA sequencing and immunohistochemical staining of p53 protein within tumor nuclei were performed. RESULTS: Primary tumors displayed p53 mutations within exons 5-9 in 41% of patients. No mutations were found in exons 4, 10, or 11. Forty-one percent of metastatic lesions had the same single mutation that was found in the primary tumor, whereas 11% of metastatic lesions had one additional mutation within exons 5-9; 22% had mutations only in their liver metastases, whereas corresponding primary tumors displayed wild-type p53. None of the patients had mutated p53 in their primary tumor and wild type in their metastases. Survival after undergoing liver resection was correlated negatively (P < 0.05-0.01) with Duke Stages A-D classification of the primary tumors, tumor differentiation, and radicality (> 0.7-0.8 mm) of resected liver metastases. CONCLUSIONS: The presence of p53 mutations in patients with metastatic lesions was related significantly (P < 0.003) to better survival after the patients underwent liver resection compared with patients with wild type p53 in their metastatic lesions. This finding was not related to covariates, such as Duke classification, tumor differentiation, type of liver metastasis, or metastatic radicality during resections. Explanations for this unexpected finding remain unclear, although the authors speculate that occult tumor cells with p53 mutations may be less responsive to growth factor(s) exposure during hepatic regeneration after resection.

Time of day type of food--relation to mood and hunger during 24 hours of constant conditions.

A six-day high-carbohydrate meal (HC; 65 E% (energy percent) carbohydrates, 20 E% fat and 15 E% protein) and a six-day high-fat meal (HF; 40 E% carbohydrates, 45 E% fat and 15 E% protein) were given to seven healthy subjects in a crossover design. On the last day subjects were kept awake for 24 hours in a metabolic laboratory while substrate utilisation and energy expenditure were measured by indirect calorimetry. The subjects were given isocaloric meals every four hours. Results showed that hunger decreased at night (F = 4.2, p < 0.05) and linearly increased after meal intake. Macronutrient composition (fat/carbohydrates) seemed to be of less importance for hunger. Hunger and thirst were found to be strongly associated with gastrointestinal substances, for hunger the strongest being a negative correlation with triacylglycerol (partial correlation = -0.39). It is suggested that it might not be necessary for shift workers to eat full portions at night but that satiation will occur with less food. Possibly lack of adjustment of nocturnal food intake might be one reason why overweight is common in shift work populations.