Bayesian clustering of farm types using the mixtures model

A Bayesian method of classifying observations that are assumed to come from a number of distinct subpopulations is outlined. The method is illustrated with simulated data and applied to the classification of farms according to their level and variability of income. The resultant classification shows a greater diversity of technical charactersitics within farm types than is conventionally the case. The range of mean farm income between groups in the new classification is wider than that of the conventional method and the variability of income within groups is narrower. Results show that the highest income group in 2000 included large specialist dairy farmers and pig and poultry producers, whilst in 2001 it included large and small specialist dairy farms and large mixed dairy and arable farms. In both years the lowest income group is dominated by non-milk producing livestock farms.

Changes in in vitro susceptibility of influenza A H3N2 viruses to a neuraminidase inhibitor drug during evolution in the human host

Objectives: Influenza A H3N2 viruses isolated recently have characteristic receptor binding properties that may decrease susceptibility to neuraminidase inhibitor drugs. A panel of clinical isolates and recombinant viruses generated by reverse genetics were characterized and tested for susceptibility to zanamivir. Methods: Plaque reduction assays and neuraminidase enzyme inhibition assays were used to assess susceptibility to zanamivir. Receptor binding properties of the viruses were characterized by differential agglutination of red blood cells (RBCs) from different species. Sequence analysis of the haemagglutinin (HA) and neuraminidase (NA) genes was carried out. Results: Characterization of a panel of H3N2 clinical isolates from 1968 to 2000 showed a gradual decrease in agglutination of chicken and guinea pig RBCs over time, although all isolates could agglutinate turkey RBCs equally. Sequence analysis of the HA and NA genes identified mutations in conserved residues of the HA1 receptor binding site, in particular Leu-226 --> Ile-226/Val-226, and modification of potential glycosylation site motifs. This may be indicative of changes in virus binding to sialic acid (SA) receptors in recent years. Although recent isolates had reduced susceptibility to zanamivir in MDCK cell based plaque reduction assays, no difference was found in an NA enzyme-inhibition assay. Assays with recombinant isogenic viruses showed that the recent HA, but not the NA, conferred reduced susceptibility to zanamivir. Conclusion: This study demonstrates that recent clinical isolates of influenza A H3N2 virus no longer agglutinate chicken RBCs, but despite significant receptor binding changes as a result of changes in HA, there was little variation in sensitivity of the NA to zanamivir.

Hespellia stercorisuis gen. nov., sp nov and Hespellia porcina sp nov., isolated from swine manure storage pits

Four Gram-positive-staining, strictly anaerobic, non-spore-forming, rod-shaped organisms were isolated from a pig manure storage pit. Comparative 16S rRNA gene sequence analysis revealed that the isolates belonged to two related but distinct groups. Sequence analysis showed that the two groups of isolates were highly related to each other (approx. 97% 16S rRNA gene sequence similarity), forming a distinct cluster within the Clostridium coccoides suprageneric rDNA grouping. Biochemical and physiological studies confirmed the division of the isolates into two related, albeit distinct, groups. Based on both phenotypic and phylogenetic evidence, it is proposed that the unidentified rod-shaped isolates from pig manure should be classified in a novel genus, Hespellia gen. nov., as Hespellia stercorisuis sp. nov. and Hespellia porcina sp. nov. The type species of the novel genus is H. stercorisuis (type strain, PC18(T) = NRRL B-23456(T) = CCUG 46279(T) = ATCC BAA-677(T)) and the type strain of H. porcina is PC80(T) (= NRRL B-23458(T) = ATCC BAA-674(T)).

A novel galactooligosaccharide mixture increases the bifidobacterial population numbers in a continuous in vitro fermentation system and in the proximal colonic contents of pigs in vivo

Prebiotics are nondigestible food ingredients that encourage proliferation of selected groups of the colonic microflora, thereby altering the composition toward a more beneficial community. In the present study, the prebiotic potential of a novel galactooligosaccharide (GOS) mixture, produced by the activity of galactosyltransferases from Bifidobacterium bifidum 41171 on lactose, was assessed in vitro and in a parallel continuous randomized pig trial. In situ fluorescent hybridization with 16S rRNA-targeted probes was used to investigate changes in total bacteria, bifidobacteria, lactobacilli, bacteroides, and Clostridium histolyticum group in response to supplementing the novel GOS mixture. In a 3-stage continuous culture system, the bifidobacterial numbers for the first 2 vessels, which represented the proximal and traverse colon, increased (P < 0.05) after the addition of the oligosaccharide mixture. In addition, the oligosaccharide mixture strongly inhibited the attachment of enterohepatic Escherichia coli (P < 0.01) and Salmonella enterica serotype Typhimurium (P < 0.01) to HT29 cells. Addition of the novel mixture at 4% (wt:wt) to a commercial diet increased the density of bificlobacteria (P < 0.001) and the acetate concentration (P < 0.001), and decreased the pH (P < 0.001) compared with the control diet and the control diet supplemented with inulin, suggesting a great prebiotic potential for the novel oligosaccharide mixture. J. Nutr. 135: 1726-1731, 2005.

Subdoligranulum variabile gen. nov., sp nov from human feces

During studies on the microflora of human feces we have isolated a strictly anaerobic, non-spore-forming, Gram-negative staining organism which exhibits a somewhat variable coccus-shaped morphology. Comparative 16S ribosomal RNA gene sequencing studies show the unidentified organism is phylogenetically a member of the Clostridium leptum supra-generic rRNA cluster and displays a close affinity to some rDNA clones derived from human and pig feces. The nearest named relatives of the unidentified isolate corresponded to Faecalibacterium prausnitzii (formerly Fusobacterium prausnitzii) displaying a 16S rRNA sequence divergence of approximately 9%, with Anaerofilum agile and A. pentosovorans the next closest relatives of the unidentified bacterium (sequence divergence approximately 10%). Based on phenotypic and phylogenetic considerations, it is proposed that the unusual coccoid-shaped organism be classified as a new genus and species, Subdoligranulum variabile. The type strain of S. variabile is BI 114(T) (= CCUG 47106(T) = DSM 15176(T)). (C) 2004 Elsevier Ltd. All rights reserved.

Atopostipes suicloacale gen. nov., sp. nov., isolated from an underground swine manure storage pit

Phenotypic and molecular genetic studies were performed on an unknown facultative anaerobic, catalase-negative, non-spore-forming, rod-shaped bacterium isolated from a pig manure storage pit. The unknown bacterium was nutritionally fastidious with growth enhanced by the addition of rumen fluid and was phenotypically initially identified as an Eubacterium species. Comparative 16S rRNA gene sequencing studies, however, revealed that the unknown bacterium was phylogenetically distant from Eubacterium limosum (the type species of the genus Eubacterium) and related organisms. Phylogenetically, the unknown species displayed a close association with an uncultured organism from human subgingival plaque and formed an unknown sub-line within a cluster of organisms which includes Alloioccoccus otitis, Alkalibacterium olivoapovliticus, Allofustis seminis, Dolosigranulum pigrum, and related organisms, within the low mol% G + C Gram-positive bacteria. Sequence divergence values of > 8% with all known taxonomically recognised taxa, however, clearly indicates the novel bacterium represents a hitherto unknown genus. Based on both phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium from pig manure be classified in a new genus and species, as Atopostipes suicloacale gen. nov., sp. nov. The type strain of Atopostipes suicloacale is PPC79(T) = NRRL 23919(T) = DSM 15692(T). Crown Copyright (C) 2004 Published by Elsevier Ltd. All rights reserved.

The synthesis and cytotoxic evaluation of a series of benzodioxole substituted titanocenes

Using 6-benzo[1,3]dioxolefulvene (1a), a series of benzodioxole substituted titanocenes was synthesized. The benzyl-substituted titanocene bis[(benzo[1,3]dioxole)-5-methylcyclopentadienyl] titanium (IV) dichloride (2a) was synthesized from the reaction of Super Hydride with 1a. An X-ray determined crystal structure was obtained for 2a. The ansa-titanocene (1,2-di(cyclopentadienyl)1,2-di-(benzo[1,3]dioxole)-ethanediyl) titanium(IV) dichloride (2b) was synthesized by reductive dimerisation of la with titanium dichloride. The diarylmethyl substituted titanocene bis(di(benzo[1,3]dioxole)-S-methylcyclopentadienyl) titanium(IV) dichloride (20 was synthesized by reacting la with the para-lithiated benzodioxole followed by transmetallation with titanium tetrachloride. When titanocenes 2a-c were tested against pig kidney (LLC-PK) cells inhibitory concentrations (IC50) of 2.8 X 10(-4), 1.6 x 10(-4) and 7.6 x 10(-5) m, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, when compared with unsubstituted titanocene dichloride, but are not as impressive as values obtained for titanocenes previously synthesized using the above methods. Copyright (c) 2006 John Wiley & Sons, Ltd.

Heteroaryl substituted titanocenes as potential anti-cancer drugs

From the reaction of Super Hydride (LiBEt3H) with 6-(furyl)fulvene (1a), 6-(thiophenyl)fulvene (1b) or 6-(N-methyl-pyrrole)fulvene (1c) the corresponding lithium cyclopentadienide intermediates (2a-c) were obtained. These intermediates were reacted with titanium tetrachloride and bis-[(furyl-2-cyclopentadienylmethane)] titanium(IV) dichloride (3a) and bis-[(thiophenyl-2-cyclopentadienylmethane)] titanium(IV) dichloride (3b) and bis-[(N-methylpyrrole-2-cyclopentadienylmethane)] titanium(IV) dichloride (3c) were obtained and subsequently characterised by X-ray crystallography. When titanocenes 3a-c were tested against pig kidney (LLC-PK) cells inhibitory concentrations (IC50) of 1.6 x 10(-4) M, 1.5 x 10(-4) M and 9.1 x 10(-5) M, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, when compared to their corresponding ansa substituted analogues and also in comparison to unsubstituted titanocene dichloride. (c) 2006 Elsevier Inc. All rights reserved.

Proliferative and antiproliferative effects in substituted titanocene anticancer drugs

Substituted titanocenes like ansa-titanocenes, diarylmethyl-substituted and benzyl-substituted titanocenes, are known for their cytotoxic potential and they can be synthesised using 6-arylfulvenes. Nevertheless, in the case of using 6-(4-morpholin-4yl-phenyl) fulvene (5a) or 6-{[bis-(2-methoxyethyl)amino]phenyl} fulvene (5b) the synthetic possibilities seem to be limited, but the morpholino and the bis-(2-methoxyethyl)amino substituent are in terms of an improved water solubility and drug availability in the cell very interesting groups. The corresponding benzaldehydes, which are the starting material for the synthesis of these fulvenes, were not commercially available and therefore, a modified synthetic approach had to be introduced. Nevertheless, the reactivity of the obtained fulvenes was unexpected and only the ansa-titanocene bis-[{[bis-(2-methoxyethyl)amino]phenyl}cyclopentadienyl] titanium(IV) dichloride (6b) and the benzyl-substituted titanocene [1,2-di(cyclopentadienyl)-1,2-di(4-morpholin-4yl-phenyl)-ethanediyl] titanium dichloride (8a) could be obtained and characterised. When the benzyl-substituted titanocene (8a) was tested against pig kidney cells (LLC-PK) an anti-proliferative effect, resulting in an IC50 value of 25 mu M, was observed. This IC50 value is in the lower range of the cytotoxicities evaluated for titanocenes up to now. The ansa-titanocene (6b) showed surprisingly, when tested on the same cell line, a proliferative effect.

Glycol methyl ether and glycol amine substituted titanocenes as antitumor agents

6-[4-(2-Methoxyethoxy)phenyl]fulvene (3a) and 6-(4-[2-(di-methylamino)ethoxy]phenyl)fulvene (3b) were prepared as starting materials for the synthesis of three dofferent classes of titanocenes, which are ansa-titanocenes, diarylmethyl-substituted titanicenes and benzyl-substituted titanocenes and benyzyl-subtituted titanocenes. Because the synthetic possibilities seem to be limited, only ansa-titanocene {1,2-bis(cyclopentadienyl)-1,2-bis[4-(2-methoxyethoxy)phenyl]ethanediyl}titanium dichloride (4a) and benzyl-substituted titanocene bis-{[4-(2-methoxyethoxy)benzyl]cyclopentadienyl}titantium(IV) dichloride (6a) were obtained and characterised. The change in the substitution pattern f the phenyl moiety from an oxygen atom to a nitrogen atom had such a big influence on the reaction that not one compound of the threee titanocene classes could be synthesised, and it was also not possible to obtain diarylmethyl-substituted titanocenes with the use of either of the fulvenes. When benzyl-substituted titanocene 6a was tested agianst pig kidney cells (LLC-PK), an antiproliferative effect that result in an IC50 value of 43 mu m, was observed. This IC50 value is in the lower range of the cytotoxicities evaluated for titanocenes up to now. ansa-Titanocene 4a surprisingly showed, when tested on the same cell line, a proliferative effect together with a fast rate of hydrolysis.

Diheteroarylmethyl substituted titanocenes: a novel class of possible anti-cancer drugs

From the reaction of tert-butyl lithium or n-butyl lithium with N-methylpyrrole (1a), furan (1b) or 2-bromo-thiophen (1c), 2-N-methylpyrrolyl lithium (2a), 2-furyl lithium (2b) or 2-thiophenyl lithium (2c), respectively, was obtained. When reacted with 6-(2-N-methylpyrrolyl) fulvene (3a), 6-(2-furyl) fulvene (3b) or 6-(2-thiophenyl) fulvene (3c), the corresponding lithiated intermediates were formed (4a-c). Titanocenes (5a-c) were obtained through transmetallation with titanium tetrachloride. When these titanocenes were tested against pig kidney epithelial (LLC-PK) cells, inhibitory concentrations (IC50) of 32 mu M, 140 mu M, and 240 mu M, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, compared to their ansa-analogues. (c) 2006 Elsevier B.V. All rights reserved.

Diarylmethyl substituted titanocenes: promising anti-cancer drugs

From the reaction of tert-butyl lithium with p-bromo-N,N-dimethylaniline (1a), p-bromoanisole (1b) or 1-bromo-3,5-dimethoxybenzene (1c), p-N,N-dimethylanityl lithium (2a), p-anisyl lithium (2b) or (3,5-dimethoxyphenyl) lithium (2c), respectively, were obtained. When reacted with 6-(p-N,N-dimethylanilinyl)fulvene (3a), 6-(p-methoxyphenyl)fulvene (3b) or 3,5-(dimethoxyphenyl)fulvene (3c), the corresponding lithiated intermediates were formed (4a-c). Titanium tetrachloride was added "in situ", obtaining titanocenes 5a-C, respectively. When these titanocenes were tested against pig kidney carcinoma (LLC-PK) cells, inhibitory concentrations (IC50) Of 3.8 x 10(-5) M, 4.5 x 10(-5) M, and 7.8 x 10(-5) M, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, compared to their ansa-analogues. (c) 2006 Elsevier Ltd. All rights reserved.

The effects of paeonol on the electrophysiological properties of cardiac ventricular myocytes

Previous studies have shown that "Mudanpi", a Chinese herbal medicine, has a significant cardioprotective effect against myocardial ischaemia. Based on these findings we hypothesised that paeonol, the main component of Mudanpi, might have an effect on the cellular electrophysiology of cardiac ventricular myocytes. The effects of paeonol on the action potential and ion channels of cardiac ventricular myocytes were studied using the standard whole-cell configuration of the patch-clamp technique. Ventricular myocytes were isolated from the hearts of adult guinea-pig by enzymic dispersion. The myocytes were continuously perfused with various experimental solutions at room temperature and paeonol applied in the perfusate. Action potentials and membrane currents were recorded using both current and voltage clamp modes of the patch-clamp technique. Paeonol, at concentrations 160 mu M and 640 mu M, decreased the action potential upstroke phase, an action associated with the blockade of the voltage-gated, fast sodium channel. The effects of paeonol on both action potential and Na+ current were concentration dependent. Paeonol had a high affinity for inactivated sodium channels. Paeonol also shortened the action potential duration, in a manner not associated with the blockade of the calcium current, or the enhancement of potassium currents. These findings suggest that paeonol, and therefore Mudanpi, may possess antiarrhythmic activity, which may confer its cardioprotective effects. (c) 2006 Elsevier B.V All rights reserved.

Porcine models for the metabolic syndrome, digestive and bone disorders: a general overview

The aim of this review article is to provide an overview of the role of pigs as a biomedical model for humans. The usefulness and limitations of porcine models have been discussed in terms of metabolic, cardiovascular, digestive and bone diseases in humans. Domestic pigs and minipigs are the main categories of pigs used as biomedical models. One drawback of minipigs is that they are in short supply and expensive compared with domestic pigs, which in contrast cost more to house, feed and medicate. Different porcine breeds show different responses to the induction of specific diseases. For example, ossabaw minipigs provide a better model than Yucatan for the metabolic syndrome as they exhibit obesity, insulin resistance and hypertension, all of which are absent in the Yucatan. Similar metabolic/physiological differences exist between domestic breeds (e.g. Meishan v. Pietrain). The modern commercial (e.g. Large White) domestic pig has been the preferred model for developmental programming due to the 2- to 3-fold variation in body weight among littermates providing a natural form of foetal growth retardation not observed in ancient (e.g. Meishan) domestic breeds. Pigs have been increasingly used to study chronic ischaemia, therapeutic angiogenesis, hypertrophic cardiomyopathy and abdominal aortic aneurysm as their coronary anatomy and physiology are similar to humans. Type 1 and II diabetes can be induced in swine using dietary regimes and/or administration of streptozotocin. Pigs are a good and extensively used model for specific nutritional studies as their protein and lipid metabolism is comparable with humans, although pigs are not as sensitive to protein restriction as rodents. Neonatal and weanling pigs have been used to examine the pathophysiology and prevention/treatment of microbial-associated diseases and immune system disorders. A porcine model mimicking various degrees of prematurity in infants receiving total parenteral nutrition has been established to investigate gut development, amino acid metabolism and non-alcoholic fatty liver disease. Endoscopic therapeutic methods for upper gastrointestinal tract bleeding are being developed. Bone remodelling cycle in pigs is histologically more similar to humans than that of rats or mice, and is used to examine the relationship between menopause and osteoporosis. Work has also been conducted on dental implants in pigs to consider loading; however with caution as porcine bone remodels slightly faster than human bone. We conclude that pigs are a valuable translational model to bridge the gap between classical rodent models and humans in developing new therapies to aid human health.

Improving the efficiency of energy utilization in cattle

The efficiency of energy utilisation in cattle is a determinant of the profitability of milk and beef production, as well as their environmental impact. At an animal level, meat and milk production by ruminants is less efficient than pig and poultry production, in part due to lower digestibility of forages compared with grains. However, when compared on the basis of human-edible inputs, the ruminant has a clear efficiency advantage. There has been recent interest in feed conversion efficiency (FCE) in dairy cattle and residual feed intake, an indicator of FCE, in beef cattle. Variation between animals in FCE may have genetic components, allowing selection for animals with greater efficiency and reduced environmental impact. A major source of variation in FCE is feed digestibility, and thus approaches that improve digestibility should improve FCE if rumen function is not disrupted. Methane represents a substantial loss of digestible energy from rations. Major determinants of methane emission are the amount of feed consumed and the proportions of forage and concentrates fed. In addition, feeding fat has long been known to reduce methane emission. A myriad of other supplements and additives are currently being investigated as mitigators of methane emission, but in many cases compounds effective in sheep are ineffective in lactating dairy cows. Ultimately, the adoption of ‘best practice’ in diet formulation and management may be the most effective option for reducing methane. In assessing the efficiency of energy use for milk and meat production by cattle, and their environmental impact, it is imperative that comparisons be made at a systems level, and that the wider social and economic implications of mitigation policy are considered.