Effects of butyrate on apoptosis in the pig colon and its consequences for skatole formation and tissue accumulation

Evidence exists that butyrate inhibits apoptosis of colon crypt cells in vivo so that less tryptophan from cell debris is available for skatole formation by microbes in the pig colon. In this study, potato starch containing a high proportion of resistant starch was fed to test the hypothesis that increased butyrate formation will occur in the colon and contribute to reduced epithelial cell apoptosis, thus leading to reduced skatole formation and absorption. Two groups of six barrows were provided with catheters in the jugular vein and fed either a ration with pregelatinized starch (high ileal digestibility; controls) or potato starch (low ileal digestibility; PS) as the main carbohydrate. All pigs were fed 31 MJ of metabolizable energy and 381 g of crude protein per day. The controls were fed for 19 d. The PS group received the same control ration for 10 d, and then changed to the PS ration. The total feeding period of PS consisted of a 5 d adaptation period followed by another 19 d. In the continously sampled feces, pH, short chain fatty acids, and skatole were determined. Skatole was additionally measured in blood plasma that was sampled daily. After killing barrows at the end of the feeding period, fat tissue for skatole measurement and colon tissue for histological quantification of mitosis and apoptosis were obtained. Feeding potato starch led to a rapid 2.2 fold increase of fecal butyrate when compared both with the control period of the PS group and the control group (P < 0.001). PS feeding resulted in a decrease in pH from 7.3 to 5.3 (P < 0.001) and apoptosis from 2.06 cells/crypt to 0.90 cells (P < 0.01), whereas there was no change in mitosis. Consequently, skatole decreased both in feces (controls vs PS group: 120.0 vs 1.9 microg/g; P < 0.001) and in blood plasma (1.6 vs 0.2 ng/mL; P < 0.001). The mean concentration of skatole in fat tissue was 167 ng/g tissue in controls, and below the detection limit (0.8 ng/g) in the PS group (P < 0.001). It is concluded that butyrate-dependent inhibition of apoptosis in the colon due to potato starch feeding efficiently inhibits skatole production in barrows. Because of the depressed skatole levels, improved sensory quality of pork is possible.     

Effects of malnutrition on the expression of daintain/AIF-1 in the gut mucosa of pigs

The allograft inflammatory factor (AIF-1/daintain) is a hormone-like peptide produced by activated monocytic cells in a variety of traumatic, inflammatory and degenerative lesions. Gut-derived AIF-1 has been shown to modulate insulin production and to attenuate autoimmune diabetes. As the localization of this gastrointestinal peptide in the porcine duodenum is not known and the pig is a convenient model for the study of nutritional modulation of the mucosal immune compartment, we have localized expression of AIF-1 by immunohistology in the duodenum of either malnourished (energy and protein supply 50% of demands, n = 5) or optimally fed pigs (n = 5). AIF-1 macrophages were predominantly located at the villus tip. The number of positively stained cells per high-power field was significantly (P < or = 0.001) higher in the malnourished pigs (74.6 +/- 2.44; least square means +/- SEM) compared to optimally fed pigs (32.56 +/- 1.99). It is likely that the effect in malnourished pigs can be explained by a more pronounced antigen contact of macrophages due to loss of epithelial integrity. Thus, AIF-1 is a novel marker for the study of the nutritional regulation of the mucosal immune system of the pig. AIF-1 expression in the duodenum was further validated by polymerase chain reaction and sequencing. Surprisingly, we detected a slight deviation from the original sequence (probably representing an allelic variation) and an AIF-1 splice variant, previously not known to occur in pigs.     

Abdominal pythiosis in a Bengal tiger (Panthera tigris tigris).

An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting.     

Über MaBnahmen zur Bestandssteigerung von Fledermäusennahmen zur Bestandssteigerung von Fledermäusen

Ohne Zusammenfassung     

Model studies on reactions occurring in oxidations of lignin with molecular oxygen in Alkaline Media

Basic reactions governing the degradation of lignin in oxidation with molecular oxygen are discussed emphasizing the radical (homolytic) or one-electron transfer-oxidations in the initial phase. The critical oxidation potentials (COP) according to Fieser were found to represent a useful measure for the ease of electron release from lignin-related phenolic models. At low alkalinity rough correlations were observed between the measured COPs and the initial oxygenation rates. The results obtained from quantum mechanical calculations of critical oxidation potentials are briefly discussed.The importance of phenoxy radicals and the hypothetical cyclohexadienone hydroperoxides as intermediates is outlined in view of such degradation reactions as oxidative side-chain eliminations, demethoxylations, and splitting of aromatic rings.Research performed at the Institute of Organic Chemistry, University of Vienna.     

Increased understanding of the cereal phytase complement for better mineral bio-availability and resource management

The present paper summarizes the current state of knowledge on cereal phytase that are particular relevant for improving mineral and phosphate bio-availability. Phytases can initiate the hydrolysis of phytate, the main storage form of phosphate in cereals and the major anti-nutritional factor for the bio-availability of micronutrients in human nutrition. The composition and levels of mature grain phytase activity (MGPA) in cereals is of central importance for efficient phytate hydrolysis. The MGPA varies considerably between species. Substantial activity is present in Triticeae tribe cereals like wheat, barley and rye whereas non-Triticeae cereals such as maize and rice have very little MGPA. Recent studies have determined the evolutionary relationships of phytases in Triticeae and non-Triticeae and highlighted the importance of the purple acid phosphatase phytases (PAPhys). In the Triticeae, PAPhys are synthesized during grain development (PAPhy_a) and during germination (PAPhy_b). In non-Triticeae species, only PAPhys that are mainly synthesized during germination were identified. The new knowledge provides new opportunities for modulating the MGPA in Triticeae cereals but also indicates that nutritionally relevant levels of MGPA are unlikely to be achieved in non-Triticeae by conventional breeding. Increasing MGPA in barley via cisgenesis is discussed.     

Large heterogeneity of the obesity epidemic in Danish adults

OBJECTIVE: To examine to what extent the obesity epidemic is a general phenomenon in adults by assessing the secular change, by birth cohort and age, in the prevalence of obesity and median body mass index (BMI) in Danish men and women measured between 1964 and 1994. DESIGN: Multiple cross-sectional population surveys. SETTING: The greater Copenhagen area of Denmark. SUBJECTS: The study included 17,065 men (30 336 observations) and 13,417 women (24,065 observations), aged 20-84 years. MAIN OUTCOME MEASURES: Trends in median BMI and prevalence of obesity estimated from measured height and weight in 10-year age groups. RESULTS: In general the prevalence of obesity was increasing, although in an irregular way: among men in two phases, during the 1970s and 1990s and among women only during the 1990s. Great heterogeneity was observed between birth cohorts and age groups. There was only little indication of an increasing trend in obesity prevalence for women, except for the 55-64-year-olds. In men, the prevalence of obesity was increasing in all age groups except in the youngest ones, and it was statistically significant only for men aged 35-74 years. There was no significant linear change in median BMI in any group, except for an increasing trend among men aged 50 years and above. CONCLUSION: Although the overall Danish trend for obesity prevalence, similar to trends world-wide, showed a marked increase, the trend was very heterogeneous and generally neither uniform nor significantly positive; the changes were irregular, different among men and women, and different in the different age and birth cohorts. The obesity problem in middle-aged and older men of certain birth cohorts poses a specific public health challenge. Future studies of determinants behind the heterogeneity in the development of the obesity epidemic may provide clues to its causes.     

Use of a substrate/alliinase combination to generate antifungal activity in situ

Allicin, an active ingredient of garlic, possesses a range of antimicrobial properties. Unfortunately, certain properties of the compound, such as chemical instability and low miscibility with water, have hampered its practical use in the past. Here, we show that it is possible to use a binary system consisting of the plant enzyme alliinase and its substrate alliin to generate allicin, and hence antifungal activity, in situ. During application, the two inactive components generate compounds that inhibit growth and infection-related development of the rice blast fungus Magnaporthe grisea. It is therefore possible to "trigger" biological activity in a controlled, yet effective manner. Apart from circumventing many of the drawbacks of allicin, this binary system has additional important advantages, such as low toxicity of its individual components and selective activation. Importantly, alliinase is also able to use different substrates, therefore paving the way to a range of novel, binary antimicrobial systems with custom-made chemical and biochemical properties.     

Paleo-Eskimo mtDNA genome reveals matrilineal discontinuity in Greenland

The Paleo-Eskimo Saqqaq and Independence I cultures, documented from archaeological remains in Northern Canada and Greenland, represent the earliest human expansion into the New World's northern extremes. However, their origin and genetic relationship to later cultures are unknown. We sequenced a mitochondrial genome from a Paleo-Eskimo human by using 3400-to 4500-year-old frozen hair excavated from an early Greenlandic Saqqaq settlement. The sample is distinct from modern Native Americans and Neo-Eskimos, falling within haplogroup D2a1, a group previously observed among modern Aleuts and Siberian Sireniki Yuit. This result suggests that the earliest migrants into the New World's northern extremes derived from populations in the Bering Sea area and were not directly related to Native Americans or the later Neo-Eskimos that replaced them.