Dynamic role of single-celled fungi in ruminal microbial ecology and activities.

In ruminants, high fermentation capacity is necessary to develop more efficient ruminant production systems. Greater level of production depends on the ability of the microbial ecosystem to convert organic matter into precursors of milk and meat. This has led to increased interest by animal nutritionists, biochemists and microbiologists in evaluating different strategies to manipulate the rumen biota to improve animal performance, production efficiency and animal health. One of such strategies is the use of natural feed additives such as single-celled fungi yeast. The main objectives of using yeasts as natural additives in ruminant diets include; (i) to prevent rumen microflora disorders, (ii) to improve and sustain higher production of milk and meat, (iii) to reduce rumen acidosis and bloat which adversely affect animal health and performance, (iv) to decrease the risk of ruminant-associated human pathogens and (v) to reduce the excretion of nitrogenous-based compounds, carbon dioxide and methane. Yeast, a natural feed additive, has the potential to enhance feed degradation by increasing the concentration of volatile fatty acids during fermentation processes. In addition, microbial growth in the rumen is enhanced in the presence of yeast leading to the delivery of a greater amount of microbial protein to the duodenum and high nitrogen retention. Single-celled fungi yeast has demonstrated its ability to increase fibre digestibility and lower faecal output of organic matter due to improved digestion of organic matter, which subsequently improves animal productivity. Yeast also has the ability to alter the fermentation process in the rumen in a way that reduces methane formation. Furthermore, yeast inclusion in ruminant diets has been reported to decrease toxins absorption such as mycotoxins and promote epithelial cell integrity. This review article provides information on the impact of single-celled fungi yeast as a feed supplement on ruminal microbiota and its function to improve the health and productive longevity of ruminants.

Saccharomyces cerevisiae as a probiotic feed additive to non and pseudo-ruminant feeding: a review.

The production of livestock and poultry faces major challenges to meet the global demand for meat and dairy products and eggs due to a steady increase in the world's population and the ban of antibiotics in animal production. This ban has forced animal nutritionists to seek for natural alternatives to antibiotics. In this context, the yeast Saccharomyces cerevisiae has received considerable attention in the last decade. It has been reported that feed supplementation with live yeast cells improve feed efficiency, enhance feed digestibility, increase animal performance, reduce the number of pathogenic bacteria, improve animal health and reduce the negative environmental impacts of livestock production. The current review sheds light on the effects of the use of live S. cerevisiae cells in the diets of nonruminant and pseudo-ruminant's animals and the mechanisms by which they exert its effects. This review work revealed that the addition of S. cerevisiae in poultry feed causes a phenomenon called competitive exclusion of pathogenic bacteria capable of causing disease adhere to the yeast surface, and so removing a large amount of harmful micro-organisms and allowing the Animal defend more effectively, the production of antimicrobial agents, the balancing the gut microbiota and stimulation of host adaptive immune system and improving gut morphological structure, thus these benefits are reflected on the overall poultry health. In addition, in the presence of live S. cerevisiae cells, the immunity of rabbits was improved due to the high number of white blood cell. In addition, apparent digestibility of acid and neutral detergent fibre was improved in horses and rabbits. Saccharomyces cerevisiae in pig diets augment mucosal immunity by increasing IgM and IgA activity against pathogens, enhance intestinal development and function, adsorb mycotoxins, modulate gut microbiota and reduce postweaning diarrhoea.

Identification of two novel bacterial phosphatase-encoding genes in Pseudomonas putida strain P13.

AIMS: Isolation and identification of genes encoding putative phosphatases from Pseudomonas putida strain P13 DSM 23335. METHODS AND RESULTS: By functional screening of a P. putida P13 genomic library, a number of Pho+ clones were identified. Two genes were identified that encoded proteins exhibiting both phytase and sugar phosphatase activities. The proteins were 249 and 462 amino acids, with molecular masses of 26 and 50 kDa respectively. Sequence alignments revealed no significant similarities to representatives of known phosphatase or phytase gene families. However, the genes were found to have a high similarity to members of the major facilitator superfamily (MFS). Both genes were overexpressed in Escherichia coli and the corresponding partially purified recombinant enzymes were found to have significant phytate-dephosphorylating activity. The protein designated P. putida phytase 1 (Ppp1) displayed the highest activity among potential substrates studied on Na phytate, whereas Ppp2 more likely represents a sugar phosphatase than a phytase. The optimal conditions for phytate dephosphorylation were determined as 60°C and pH 4·5 (Ppp1) or pH 5·0 (Ppp2). CONCLUSIONS: Two novel bacterial phosphatase-encoding genes, named ppp1 and ppp2, were isolated from P. putida P13 DSM 23335 by a functional screening procedure. SIGNIFICANCE AND IMPACT OF THE STUDY: Phosphatase-encoding genes are of great importance for industrial applications, particularly in agriculture. The identified phosphatase genes represent a new class of acid phosphatases.

State of the art of nonthermal and thermal processing for inactivation of micro-organisms.

Despite the constant development of novel thermal and nonthermal technologies, knowledge on the mechanisms of microbial inactivation is still very limited. Technologies such as high pressure, ultraviolet light, pulsed light, ozone, power ultrasound and cold plasma (advanced oxidation processes) have shown promising results for inactivation of micro-organisms. The efficacy of inactivation is greatly enhanced by combination of conventional (thermal) with nonthermal, or nonthermal with another nonthermal technique. The key advantages offered by nonthermal processes in combination with sublethal mild temperature (<60°C) can inactivate micro-organisms synergistically. Microbial cells, when subjected to environmental stress, can be either injured or killed. In some cases, cells are believed to be inactivated, but may only be sublethally injured leading to their recovery or, if the injury is lethal, to cell death. It is of major concern when micro-organisms adapt to stress during processing. If the cells adapt to a certain stress, it is associated with enhanced protection against other subsequent stresses. One of the most striking problems during inactivation of micro-organisms is spores. They are the most resistant form of microbial cells and relatively difficult to inactivate by common inactivation techniques, including heat sterilization, radiation, oxidizing agents and various chemicals. Various novel nonthermal processing technologies, alone or in combination, have shown potential for vegetative cells and spores inactivation. Predictive microbiology can be used to focus on the quantitative description of the microbial behaviour in food products, for a given set of environmental conditions.

Ajuga turkestanica increases Notch and Wnt signaling in aged skeletal muscle.

BACKGROUND: The declining myogenic potential of aged skeletal muscle is multifactorial. Insufficient satellite cell activity is one factor in this process. Notch and Wnt signaling are involved in various biological processes including orchestrating satellite cell activity within skeletal muscle. These pathways become dysfunctional during the aging process and may contribute to the poor skeletal muscle competency. Phytoecdysteroids are natural adaptogenic compounds with demonstrated benefit on skeletal muscle. AIM: To determine the extent to which a phytoecdysteroid enriched extract from Ajuga turkestanica (ATE) affects Notch and Wnt signaling in aged skeletal muscle. MATERIALS AND METHODS: Male C57BL/6 mice (20 months) were randomly assigned to Control (CT) or ATE treatment groups. Chow was supplemented with either vehicle (CT) or ATE (50 mg/kg/day) for 28 days. Following supplementation, the triceps brachii muscles were harvested and immunohistochemical analyses performed. Components of Notch or Wnt signaling were co-labelled with Pax7, a quiescent satellite cell marker. RESULTS: ATE supplementation significantly increased the percent of active Notch/Pax7+ nuclei (p = 0.005), Hes1/Pax7+ nuclei (p = 0.038), active B-catenin/Pax7+ nuclei (p = 0.011), and Lef1/Pax7+ nuclei (p = 0.022), compared to CT. ATE supplementation did not change the resting satellite cell number. CONCLUSIONS: ATE supplementation in aged mice increases Notch and Wnt signaling in triceps brachii muscle. If Notch and Wnt benefit skeletal muscle, then phytoecdysteroids may provide a protective effect and maintain the integrity of aged skeletal muscle.

[The novel intracellular phytase of enterobacteriaceae: isolation and properties].

For the first time phytase enzyme was isolated from Pantoea vagans 3.2 strain and was subjected to investigation. The enzyme was purified about 474-fold to apparent homogeneity from the crude extract of the strain, its primary structure was determined and it was concluded that phytase of Pantoea vagans 3.2 belongs to the family of histidine acid phosphatases. It has a molecular mass of about 46 kDa and Km for the hydrolysis of sodium phytate was 0.28 mM. Some physicochemical properties ofphytase were investigated.

Cost-effectiveness of insulin glargine versus NPH insulin for the treatment of Type 2 diabetes mellitus, modeling the interaction between hypoglycemia and glycemic control in Switzerland.

OBJECTIVE: The objective of this study was to evaluate the short-term and long-term clinical and economic outcomes associated with insulin glargine or NPH insulin in patients with Type 2 diabetes mellitus (T2DM) inadequately controlled with oral anti-diabetic drugs in Switzerland, modeling the interaction between hypoglycemia and glycemic control (HbA1c). METHODS: A validated discrete event simulation model for T2DM was used to predict incidence of short-term complications (symptomatic, nocturnal and severe hypoglycemic events) and long-term complications (microvascular and macrovascular events), life expectancy, quality-adjusted life years (QALYs) and direct medical costs in patients treated with insulin glargine or NPH insulin. The model was populated with published Swiss patient characteristics with T2DM. Baseline risks of hypoglycemic events, utility decrements of diabetes-related long-term complications and the hypoglycemia fear score were derived from the literature. Relative risk reductions of hypoglycemia adjusted for HbA1c using insulin glargine compared with NPH insulin were based on a published negative binomial meta-regression analysis. Costs of severe hypoglycemia, micro- and macrovascular events were analyzed from literature whenever possible otherwise guideline-projected resource-use estimations were valued with Swiss official prices or tariffs in 2006 CHF. Simulations were run with 1,000 patients per cohort over a time horizon of 40 years. Incremental cost effectiveness ratios (ICERs) were presented as cost per QALY and per life year gained (LYG). Future costs and clinical benefits were discounted at 3.5%. Wide-range one-way sensitivity analyses were performed. RESULTS: Insulin glargine was associated with an improvement in quality of life (0.098 QALYs per patient) and additional life expectancy (0.05 life years gained per patient) compared to NPH insulin. Incremental costs of CHF 2,578 resulted in an ICER of CHF 26,271 per QALY and CHF 51,100 per LYG. The cost per QALY was most sensitive to changes in costs, utility decrements and relative risk reductions of hypoglycemia. CONCLUSIONS: This study evaluated, for the first time, the cost effectiveness of insulin glargine versus NPH insulin for the treatment of T2DM considering the interaction between glycemic control and hypoglycemia in Switzerland. The base case and sensitivity analyses demonstrated that insulin glargine proved to be cost-effective with respect to accepted willingness to pay thresholds and therefore represents good value for money.

Application of machine learning methodology for PET-based definition of lung cancer.

We applied a learning methodology framework to assist in the threshold-based segmentation of non-small-cell lung cancer (NSCLC) tumours in positron-emission tomography-computed tomography (PET-CT) imaging for use in radiotherapy planning. Gated and standard free-breathing studies of two patients were independently analysed (four studies in total). Each study had a pet-ct and a treatment-planning ct image. The reference gross tumour volume (GTV) was identified by two experienced radiation oncologists who also determined reference standardized uptake value (SUV) thresholds that most closely approximated the GTV contour on each slice. A set of uptake distribution-related attributes was calculated for each PET slice. A machine learning algorithm was trained on a subset of the PET slices to cope with slice-to-slice variation in the optimal suv threshold: that is, to predict the most appropriate suv threshold from the calculated attributes for each slice. The algorithm's performance was evaluated using the remainder of the pet slices. A high degree of geometric similarity was achieved between the areas outlined by the predicted and the reference SUV thresholds (Jaccard index exceeding 0.82). No significant difference was found between the gated and the free-breathing results in the same patient. In this preliminary work, we demonstrated the potential applicability of a machine learning methodology as an auxiliary tool for radiation treatment planning in NSCLC.

Effects of gamma radiation on maize samples contaminated with Fusarium verticillioides.

The efficacy of gamma-irradiation as a method of decontamination of maize containing Fusarium verticillioides under controlled conditions of relative humidity (RH) (97.5%) and water activity has been studied. Maize grains inoculated with a spore suspension of F. verticillioides were irradiated to 2, 5, and 10 kGy. Thereafter, the irradiated and control samples were analyzed for the presence of fumonisins, their viable cells were counted, and their morphology was investigated by electronic microscopy. It was found possible to decrease the risk of exposure to fumonisins by irradiating maize to 5 or 10 kGy. However, at the dose of 2 kGy, the survived fungi (36%) can produce more fumonisins than the fungi in the control unirradiated samples under the same conditions.

Cost-effectiveness and cost-utility of insulin glargine compared with NPH insulin based on a 10-year simulation of long-term complications with the Diabetes Mellitus Model in patients with type 2 diabetes in Switzerland.

OBJECTIVE: The objective of this study was to evaluate the cost-effectiveness of insulin glargine compared with NPH insulin in patients with type 2 diabetes and in whom OAD (oral anti-diabetics) had failed in Switzerland. METHODS: Long-term diabetes outcomes were simulated with the Diabetes Mellitus Model (DMM) over a period of 10 years. The incidences of long-term complications (micro- and macrovascular events) were simulated for 10,000 patients over 10 years for six different scenarios. The scenarios were based on HbA1c reductions observed in clinical trials. For insulin glargine, HbA1c reductions of 0.96% (pessimistic case) and 1.24% (optimistic case) were simulated for three different HbA1c baseline values (10, 9 and 8%). For NPH insulin the HbA1c reduction was assumed to be 0.84%. A cost model and a utility model were developed in order to use the cumulated incidences of the simulations for the calculation of cost and QALYs (quality-adjusted life years). The unit costs of micro- and macrovascular events were assessed on the basis of published literature and guideline-projected resource-use estimations for Switzerland. Disutility values of diabetes-related long-term complications were derived from the literature. Total direct medical costs or QALYs were assessed by a combination of cumulated incidences of each event up to 10 years with the corresponding unit cost per event (in addition to the acquisition cost) or with disutility values per event, respectively. Events, total cost, and QALYs were discounted at 3%. In scenarios where no savings could be shown for insulin glargine, incremental cost-effectiveness ratios were calculated as the incremental cost per event prevented and the cost per QALY gained. RESULTS: Cost comparison demonstrated that insulin glargine is the dominant strategy for the optimistic case scenario starting at a baseline HbA1c value of 10% as savings in the management of complications exceeded the difference in acquisition costs after 8 years of treatment. Optimistic case scenarios for baseline HbA1c values of 9 and 8% achieved costs per QALY gained amounting to CHF 2,853 and CHF 5,711 and costs per event prevented amounting to CHF 2,054 and CHF 4,899, respectively. Pessimistic case scenarios for baseline HbA1c values of 10, 9 and 8% resulted in costs per QALY gained amounting to CHF 40,441, CHF 45,701 and CHF 49,468 and costs per event prevented amounting to CHF 27,742, CHF 32,451 and CHF 41,620, respectively. CONCLUSIONS: This study investigated the long-term health-economic implications of treating type 2 diabetes patients, in whom OAD had failed, with insulin glargine versus NPH insulin in Switzerland. The 10-year simulations demonstrated that the deltaHbA1c reductions of 0.4 and 0.12% achieved with insulin glargine led to a reduction of long-term complications, mortality and associated costs as well as to an improved quality of life. Insulin glargine proved to be cost-effective and represents good to excellent value for money compared to NPH insulin.

Glucose-1-phosphatase (AgpE) from Enterobacter cloacae displays enhanced phytase activity.

Using a screening procedure developed for detection of phytate hydrolysing enzymes, the gene agpE encoding glucose-1-phosphatase was cloned from an Enterobacter cloacae VKPM B2254 plasmid library. Sequence analysis revealed 78% identity on nucleotide and 79% identity on peptide level to Escherichia coli glucose-1-phosphatase characterising the respective gene product as a representative of acid histidine phosphatases harbouring the RH(G/N)RXRP motif. The purified recombinant protein displayed maximum specific activity of 196 U mg(-1) protein against glucose-1-phosphate but was also active against other sugar phosphates and p-nitrophenyl phosphate. High-performance ion chromatography of hydrolysis products revealed that AgpE can act as a 3-phytase but is only able to cleave off the third phosphate group from the myo-inositol sugar ring. Based on sequence comparison and catalytic behaviour against phytate, we propose to classify bacterial acid histidine phosphatases/phytases in the three following subclasses: (1) AppA-related phytases, (2) PhyK-related phytases and (3) Agp-related phytases. A distinguished activity of 32 U mg(-1) of protein towards myo-inositol-hexa-phosphate, which is two times higher than that of E. coli Agp, suggests that possibly functional differences in terms of phytase activity between Agp- and AppA-like acid histidine phosphatases are fluent.

Human papillomavirus status in advanced cervical cancer: predictive and prognostic significance for curative radiation treatment.

Human papillomavirus (HPV) infection plays a major role in oncogenesis of squamous cell carcinoma of the cervix. This study was performed to investigate if HPV status and E2 gene integrity are prognostic parameters for clinical outcome and predictive for radiation response. Forty women with locally advanced cervical cancer treated with curative radiotherapy were analyzed for HPV infection and E2 gene integrity by multiplex polymerase chain reaction. Statistical analyses were performed for overall survival, disease-free survival (DFS), local progression-free survival, and treatment response (clinical complete remission). Twenty-eight (70%) of 40 carcinomas were HPV positive. The only significant factor for a better overall survival, DFS, and local progression-free survival was HPV positivity (P < 0.02, P= 0.02, and P < 0.05, log-rank, respectively). HPV-positive tumors had a significantly better clinical complete remission (67% vs 33%, P= 0.04, Fisher's exact test). An intact E2 gene region showed a trend for a better DFS (P= 0.1, log-rank). This study reveals HPV as an independent prognostic parameter for outcome and radiation response. Integration of the virus genome into host cell DNA might be a molecular target to determine the treatment response of HPV-positive cancers.

A multi-criteria approach to Great Barrier Reef catchment (Queensland, Australia) diffuse-source pollution problem.

This paper presents a multi-criteria based tool for assessing the relative impact of diffuse-source pollution to the Great Barrier Reef (GBR) from the river basins draining into the GBR lagoon. The assessment integrates biophysical and ecological data of water quality and pollutant concentrations with socio-economic information pertaining to non-point source pollution and (potential) pollutant impact. The tool generates scores for each river basin against four criteria, thus profiling the basins and enabling prioritization of management alternatives between and within basins. The results support policy development for pollution control through community participation, scientific data integration and expert knowledge contributed by people from across the catchment. The results specifically provided support for the Reef Water Quality Protection Plan, released in October 2003. The aim of the plan is to provide a framework for reducing discharge of sediment, nutrient and other diffuse-source loads and (potential) impact of that discharge and for prioritising management actions both between and within river basins.

Correlation between the tumoral expression of beta3-integrin and outcome in cervical cancer patients who had undergone radiotherapy.

Integrins are cell-surface receptors, which mediate cell-to-cell and cell-to-extracellular matrix adhesion. Besides playing an important role in tumour angiogenesis, beta3-integrin is also expressed in several types of epithelial cancer cells. It was the purpose of the present study to evaluate the prognostic value of beta3-integrin expression in patients with cervical cancer. Biopsies were taken from 82 patients with squamous cell or adenocarcinomas of the uterine cervix who had undergone external-beam radiotherapy with or without brachytherapy. These tissue samples were analysed immunohistochemically for the expression of beta3-integrin. The impact of immunoreactivity for beta3-integrin on survival end points was assessed by univariate and multivariate analyses, and its correlation with clinicopathological characteristics evaluated by crosstabulations. beta3-integrin was expressed in 61% (50 of 82) of the patients. Kaplan-Meier curves revealed local progression-free survival, distant metastasis-free survival and cause-specific survival to be significantly shorter (P-values according to the log-rank test: 0.002, 0.04 and 0.01, respectively) in patients with beta3-integrin expression. The prognostic impact of this parameter was even higher than for other well-known prognostic parameters and remained statistically significant in the multivariate analyses. beta3-integrin, which is expressed in the majority of patients with advanced cervical cancer, has a significant prognostic impact on outcome according to univariate and multivariate analyses.

Introduction of a novel dose saving acquisition mode for the PortalVision aS500 EPID to facilitate on-line patient setup verification.

In external beam radiotherapy, electronic portal imaging becomes more and more an indispensable tool for the verification of the patient setup. For the safe clinical introduction of high dose conformal radiotherapy like intensity modulated radiation therapy, on-line patient setup verification is a prerequisite to ensure that the planned dosimetric coverage of the tumor volume is actually realized in the patient. Since the direction of setup fields often deviates from the direction of the treatment beams, extra dose is delivered to the patient during the acquisition of these portal images which may reach clinical relevance. The aim of this work was to develop a new acquisition mode for the PortalVision aS500 electronic portal imaging device from Varian Medical Systems that allows one to take portal images with reduced dose while keeping good image quality. The new acquisition mode, called RadMode, selectively enables and disables beam pulses during image acquisition allowing one to stop wasting valuable dose during the initial acquisition of "reset frames." Images of excellent quality can be taken with 1 MU only. This low dose per image facilitates daily setup verification with considerably reduced extra dose.

Predicting subcellular localization of proteins using machine-learned classifiers.

MOTIVATION: Identifying the destination or localization of proteins is key to understanding their function and facilitating their purification. A number of existing computational prediction methods are based on sequence analysis. However, these methods are limited in scope, accuracy and most particularly breadth of coverage. Rather than using sequence information alone, we have explored the use of database text annotations from homologs and machine learning to substantially improve the prediction of subcellular location. RESULTS: We have constructed five machine-learning classifiers for predicting subcellular localization of proteins from animals, plants, fungi, Gram-negative bacteria and Gram-positive bacteria, which are 81% accurate for fungi and 92-94% accurate for the other four categories. These are the most accurate subcellular predictors across the widest set of organisms ever published. Our predictors are part of the Proteome Analyst web-service.

Molecular and physiological characterisation of a 3-phytase from soil bacterium Klebsiella sp. ASR1.

Klebsiella sp. strain ASR1 isolated from an Indonesian rice field is able to hydrolyse myo-inositol hexakis phosphate (phytate). The phytase protein was purified and characterised as a 42 kDa protein accepting phytate, NADP and sugar phosphates as substrates. The corresponding gene (phyK) was cloned from chromosomal DNA using a combined approach of protein and genome analysis, and expressed in Escherichia coli. The recombinant enzyme was identified as a 3-phytase yielding myo-inositol monophosphate, Ins(2)P, as the final product of enzymatic phytate hydrolysis. Based on its amino acid sequence, PhyK appears to be a member of a hitherto unknown subfamily of histidine acid phytate-degrading enzymes with the active site RHGXRXP and HD sequence motifs, and is different from other general phosphatases and phytases. Due to its ability to degrade sodium phytate to the mono phosphate ester, the phyK gene product is an interesting candidate for industrial and agricultural applications to make phytate phosphorous available for plant and animal nutrition.