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Prediction of portal and hepatic blood flow from intake level data in cattle
There is growing interest in developing integrated post-absorptive metabolism models for dairy 30 cattle. An integral part of linking a multi-organ post-absorptive model is the prediction of nutrient 31 fluxes between organs, and thus blood flow. It was the purpose of this paper to use a multivariate 32 meta-analysis approach to model portal blood flow (PORBF) and hepatic venous blood flow 33 (HEPBF) simultaneously, with evaluation of hepatic arterial blood flow (ARTBF; ARTBF = 34 HEPBF β PORBF) and PORBF/HEPBF (%) as calculated values. The database used to develop 35 equations consisted of 296 individual animal observations (lactating and dry dairy cows and beef 36 cattle) and 55 treatments from 17 studies, and a separate evaluation database consisted of 34 37 treatment means (lactating dairy cows and beef cattle) from 9 studies obtained from the literature. 38 Both databases had information on DMI, MEI, body weight and a basic description of the diet 39 including crude protein intake and forage proportion of the diet (FP; %). Blood flow (L/h or L/kg 40 BW0.75/h) and either DMI or MEI (g or MJ/d or g or MJ/kg BW0.75/d) with linear and quadratic 41 fits were examined. Equations were developed using cow within experiment and experiment as 42 random effects, and blood flow location as a repeated effect. Upon evaluation with the evaluation 43 database, equations based on DMI typically resulted in lower root mean square prediction errors, 44 expressed as a % of the observed mean (rMSPE%) and higher concordance correlation coefficient 45 (CCC) values than equations based on MEI. Quadratic equation terms were frequently non-46 significant, and the quadratic equations did not out-perform their linear counterparts. The best 47 performing blood flow equations were: PORBF (L/h) = 202 (Β± 45.6) + 83.6 (Β± 3.11) Γ DMI (kg/d) and HEPBF (L/h) = 186 (Β± 45.4) + 103.8 (Β± 3.10) Γ DMI (kg/d), with rMSPE% values of 17.5 and 49 16.6 and CCC values of 0.93 and 0.94, respectively. The residuals (predicted β observed) for 50 PORBF/HEPBF were significantly related to the forage % of the diet, and thus equations for 51
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PORBF and HEPBF based on forage and concentrate DMI were developed: PORBF (L/h) = 210 52 (Β± 51.0) + 82.9 (Β± 6.43) Γ Forage (kg DM/d) + 82.9 (Β± 6.04) Γ Concentrate (kg DM/d), and 53 HEPBF (L/h) = 184 (Β± 50.6) + 92.6 (Β± 6.28) Γ Forage (kg DM/d) + 114.2 (Β± 5.88) Γ Concentrate 54 (kg DM/d), where rMSPE% values were 17.5 and 17.6 and CCC values were 0.93 and 0.94, 55 respectively. Division of DMI into forage and concentrate fractions improved the joint Bayesian 56 Information Criterion (BIC) value for PORBF and HEPBF (BIC = 6512 vs. 7303), as well as 57 slightly improved the rMSPE and CCC for ARTBF and PORBF/HEPBF. This was despite 58 minimal changes in PORBF and HEPBF predictions. Developed equations predicted blood flow 59 well, and could easily be used within a post absorptive model of nutrient metabolism. Results also 60 suggest different sensitivity of PORBF and HEPBF to the composition of DMI, and accounting 61 for this difference resulted in improved ARTBF predictions
Optimizing expression and purification of an ATP-binding gene gsiA from Escherichia coli k-12 by using GFP fusion
The cloning, expression and purification of the glutathione (sulfur) import system ATP-binding protein (gsiA) was carried out. The coding sequence of Escherichia coli gsiA, which encodes the ATP-binding protein of a glutathione importer, was amplified by PCR, and then inserted into a prokaryotic expression vector pWaldo-GFPe harboring green fluorescent protein (GFP) reporter gene. The resulting recombinant plasmid pWaldo-GFP-GsiA was transformed into various E. coli strains, and expression conditions were optimized. The effect of five E. coli expression strains on the production of the recombinant gsiA protein was evaluated. E. coli BL21 (DE3) was found to be the most productive strain for GsiA-GFP fusion-protein expression, most of which was insoluble fraction. However, results from in-gel and Western blot analysis suggested that expression of recombinant GsiA in Rosetta (DE3) provides an efficient source in soluble form. By using GFP as reporter, the most suitable host strain was conveniently obtained, whereby optimizing conditions for overexpression and purification of the proteins for further functional and structural studies, became, not only less laborious, but also time-saving
Carcinogenic Effects in a Phenylketonuria Mouse Model
Phenylketonuria (PKU) is a metabolic disorder caused by impaired phenylalanine hydroxylase (PAH). This condition results in hyperphenylalaninemia and elevated levels of abnormal phenylalanine metabolites, among which is phenylacetic acid/phenylacetate (PA). In recent years, PA and its analogs were found to have anticancer activity against a variety of malignancies suggesting the possibility that PKU may offer protection against cancer through chronically elevated levels of PA. We tested this hypothesis in a genetic mouse model of PKU (PAHenu2) which has a biochemical profile that closely resembles that of human PKU. Plasma levels of phenylalanine in homozygous (HMZ) PAHenu2 mice were >12-fold those of heterozygous (HTZ) littermates while tyrosine levels were reduced. Phenylketones, including PA, were also markedly elevated to the range seen in the human disease. Mice were subjected to 7,12 dimethylbenz[a]anthracene (DMBA) carcinogenesis, a model which is sensitive to the anticancer effects of the PA derivative 4-chlorophenylacetate (4-CPA). Tumor induction by DMBA was not significantly different between the HTZ and HMZ mice, either in total tumor development or in the type of cancers that arose. HMZ mice were then treated with 4-CPA as positive controls for the anticancer effects of PA and to evaluate its possible effects on phenylalanine metabolism in PKU mice. 4-CPA had no effect on the plasma concentrations of phenylalanine, phenylketones, or tyrosine. Surprisingly, the HMZ mice treated with 4-CPA developed an unexplained neuromuscular syndrome which precluded its use in these animals as an anticancer agent. Together, these studies support the use of PAHenu2 mice as a model for studying human PKU. Chronically elevated levels of PA in the PAHenu2 mice were not protective against cancer
Avoidable mortality attributable to anthropogenic fine particulate matter (Pm2.5) in Australia
Ambient fine particulate matter 2.5) air pollution increases premature mortalityglobally. Some PM2.5 is natural, but anthropogenic PM2.5 is comparatively avoidable. We determinedthe impact of long-term exposures to the anthropogenic PM component on mortality in Australia.PM2.5-attributable deaths were calculated for all Australian Statistical Area 2 (SA2; n = 2310) regions.All-cause death rates from Australian mortality and population databases were combined withannual anthropogenic PM2.5 exposures for the years 2006β2016. Relative risk estimates were derivedfrom the literature. Population-weighted average PM2.5 concentrations were estimated in eachSA2 using a satellite and land use regression model for Australia. PM2.5-attributable mortality wascalculated using a health-impact assessment methodology with life tables and all-cause death rates.The changes in life expectancy (LE) from birth, years of life lost (YLL), and economic cost of lostlife years were calculated using the 2019 value of a statistical life. Nationally, long-term populationweighted average total and anthropogenic PM2.5 concentrations were 6.5 Β΅g/m3(min 1.2βmax 14.2)and 3.2 Β΅g/m3(min 0βmax 9.5), respectively. Annually, anthropogenic PM2.5-pollution is associatedwith 2616 (95% confidence intervals 1712, 3455) deaths, corresponding to a 0.2-year (95% CI 0.14, 0.28)reduction in LE for children aged 0β4 years, 38,962 (95%CI 25,391, 51,669) YLL and an average annualeconomic burden of 4.0 billion, $8.1 billion). We conclude that the anthropogenicPM2.5-related costs of mortality in Australia are higher than community standards should allow,and reductions in emissions are recommended to achieve avoidable mortality
An Extremes of Phenotype Approach Confirms Significant Genetic Heterogeneity in Patients with Ulcerative Colitis
Background and Aims: Ulcerative colitis [UC] is a major form of inflammatory bowel disease globally. Phenotypic heterogeneity is defined by several variables including age of onset and disease extent. The genetics of disease severity remains poorly understood. To further investigate this, we performed a genome wide association [GWA] study using an extremes of phenotype strategy. Methods: We conducted GWA analyses in 311 patients with medically refractory UC [MRUC], 287 with non-medically refractory UC [nonMRUC] and 583 controls. Odds ratios [ORs] were calculated for known risk variants comparing MRUC and non-MRUC, and controls. Results: MRUCβcontrol analysis had the greatest yield of genome-wide significant single nucleotide polymorphisms [SNPs] [2018], including lead SNP = rs111838972 [OR = 1.82, p = 6.28 Γ 10β9] near MMEL1 and a locus in the human leukocyte antigen [HLA] region [lead SNP = rs144717024, OR = 12.23, p = 1.7 Γ 10β19]. ORs for the lead SNPs were significantly higher in MRUC compared to non-MRUC [p < 9.0 Γ 10β6]. No SNPs reached significance in the non-MRUCβcontrol analysis (top SNP, rs7680780 [OR 2.70, p = 5.56 Γ 10β8). We replicate findings for rs4151651 in the Complement Factor B [CFB] gene and demonstrate significant changes in CFB gene expression in active UC. Detailed HLA analyses support the strong associations with MHC II genes, particularly HLA-DQA1, HLA-DQB1 and HLA-DRB1 in MRUC. Conclusions: Our MRUC subgroup replicates multiple known UC risk variants in contrast to non-MRUC and demonstrates significant differences in effect sizes compared to those published. Non-MRUC cases demonstrate lower ORs similar to those published. Additional risk and prognostic loci may be identified by targeted recruitment of individuals with severe disease.Sally Mortlock, Anton Lord, Grant Montgomery, Martha Zakrzewski, Lisa A.Simms, Krupa Krishnaprasad, Katherine Hanigan, James D. Doecke, Alissa Walsh, Ian C. Lawrance, Peter A.Bampton, Jane M. Andrews, Gillian Mahy, Susan J. Connor, Miles P.Sparrow, Sally Bell, Timothy H. Florin, Jakob Begun, Richard B. Gearry, Graham L. Radford-Smit
Environmental Emission of Pharmaceuticals from Wastewater Treatment Plants in the USA
The residual drugs, drug bioconjugates, and their metabolites, mostly from human and veterinary usage, are routinely flushed down the drain, and enter wastewater treatment plants (WWTP). Increasing population, excessive use of allopathic medicine, continual introduction of novel drugs, and existing inefficient wastewater treatment processes result in the discharge of large volumes of pharmaceuticals and their metabolites from the WWTPs into the environment. The effluent from the WWTPs globally contaminate ~25% of rivers and the lakes. Pharmaceuticals in the environment, as contaminants of emerging concerns, behave as pseudo-persistent despite their relatively short environmental half-lives in the environment. Therefore, residual levels of pharmaceuticals in the environment not only pose a threat to the wildlife but also affect human health through contaminated food and drinking water. This chapter highlights WWTPs as point-sources of their environmental emissions and various effects on the aquatic and terrestrial ecosystem
Glutathione Provides a Source of Cysteine Essential for Intracellular Multiplication of Francisella tularensis
Francisella tularensis is a highly infectious bacterium causing the zoonotic disease tularemia. Its ability to multiply and survive in macrophages is critical for its virulence. By screening a bank of HimarFT transposon mutants of the F. tularensis live vaccine strain (LVS) to isolate intracellular growth-deficient mutants, we selected one mutant in a gene encoding a putative Ξ³-glutamyl transpeptidase (GGT). This gene (FTL_0766) was hence designated ggt. The mutant strain showed impaired intracellular multiplication and was strongly attenuated for virulence in mice. Here we present evidence that the GGT activity of F. tularensis allows utilization of glutathione (GSH, Ξ³-glutamyl-cysteinyl-glycine) and Ξ³-glutamyl-cysteine dipeptide as cysteine sources to ensure intracellular growth. This is the first demonstration of the essential role of a nutrient acquisition system in the intracellular multiplication of F. tularensis. GSH is the most abundant source of cysteine in the host cytosol. Thus, the capacity this intracellular bacterial pathogen has evolved to utilize the available GSH, as a source of cysteine in the host cytosol, constitutes a paradigm of bacteriaβhost adaptation
Predisposition to Cancer Caused by Genetic and Functional Defects of Mammalian Atad5
ATAD5, the human ortholog of yeast Elg1, plays a role in PCNA deubiquitination. Since PCNA modification is important to regulate DNA damage bypass, ATAD5 may be important for suppression of genomic instability in mammals in vivo. To test this hypothesis, we generated heterozygous (Atad5+/m) mice that were haploinsuffficient for Atad5. Atad5+/m mice displayed high levels of genomic instability in vivo, and Atad5+/m mouse embryonic fibroblasts (MEFs) exhibited molecular defects in PCNA deubiquitination in response to DNA damage, as well as DNA damage hypersensitivity and high levels of genomic instability, apoptosis, and aneuploidy. Importantly, 90% of haploinsufficient Atad5+/m mice developed tumors, including sarcomas, carcinomas, and adenocarcinomas, between 11 and 20 months of age. High levels of genomic alterations were evident in tumors that arose in the Atad5+/m mice. Consistent with a role for Atad5 in suppressing tumorigenesis, we also identified somatic mutations of ATAD5 in 4.6% of sporadic human endometrial tumors, including two nonsense mutations that resulted in loss of proper ATAD5 function. Taken together, our findings indicate that loss-of-function mutations in mammalian Atad5 are sufficient to cause genomic instability and tumorigenesis
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