920 resultados para Protein phosphatase 1
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Background To investigate potential cardiovascular and other effects of long-term pharmacological interleukin 1 (IL-1) inhibition, we studied genetic variants that produce inhibition of IL-1, a master regulator of inflammation. Methods We created a genetic score combining the effects of alleles of two common variants (rs6743376 and rs1542176) that are located upstream of IL1RN, the gene encoding the IL-1 receptor antagonist (IL-1Ra; an endogenous inhibitor of both IL-1α and IL-1β); both alleles increase soluble IL-1Ra protein concentration. We compared effects on inflammation biomarkers of this genetic score with those of anakinra, the recombinant form of IL-1Ra, which has previously been studied in randomised trials of rheumatoid arthritis and other inflammatory disorders. In primary analyses, we investigated the score in relation to rheumatoid arthritis and four cardiometabolic diseases (type 2 diabetes, coronary heart disease, ischaemic stroke, and abdominal aortic aneurysm; 453 411 total participants). In exploratory analyses, we studied the relation of the score to many disease traits and to 24 other disorders of proposed relevance to IL-1 signalling (746 171 total participants). Findings For each IL1RN minor allele inherited, serum concentrations of IL-1Ra increased by 0·22 SD (95% CI 0·18–0·25; 12·5%; p=9·3 × 10−33), concentrations of interleukin 6 decreased by 0·02 SD (−0·04 to −0·01; −1·7%; p=3·5 × 10−3), and concentrations of C-reactive protein decreased by 0·03 SD (−0·04 to −0·02; −3·4%; p=7·7 × 10−14). We noted the effects of the genetic score on these inflammation biomarkers to be directionally concordant with those of anakinra. The allele count of the genetic score had roughly log-linear, dose-dependent associations with both IL-1Ra concentration and risk of coronary heart disease. For people who carried four IL-1Ra-raising alleles, the odds ratio for coronary heart disease was 1·15 (1·08–1·22; p=1·8 × 10−6) compared with people who carried no IL-1Ra-raising alleles; the per-allele odds ratio for coronary heart disease was 1·03 (1·02–1·04; p=3·9 × 10−10). Per-allele odds ratios were 0·97 (0·95–0·99; p=9·9 × 10−4) for rheumatoid arthritis, 0·99 (0·97–1·01; p=0·47) for type 2 diabetes, 1·00 (0·98–1·02; p=0·92) for ischaemic stroke, and 1·08 (1·04–1·12; p=1·8 × 10−5) for abdominal aortic aneurysm. In exploratory analyses, we observed per-allele increases in concentrations of proatherogenic lipids, including LDL-cholesterol, but no clear evidence of association for blood pressure, glycaemic traits, or any of the 24 other disorders studied. Modelling suggested that the observed increase in LDL-cholesterol could account for about a third of the association observed between the genetic score and increased coronary risk. Interpretation Human genetic data suggest that long-term dual IL-1α/β inhibition could increase cardiovascular risk and, conversely, reduce the risk of development of rheumatoid arthritis. The cardiovascular risk might, in part, be mediated through an increase in proatherogenic lipid concentrations. Funding UK Medical Research Council, British Heart Foundation, UK National Institute for Health Research, National Institute for Health Research Cambridge Biomedical Research Centre, European Research Council, and European Commission Framework Programme 7.
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Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication. Using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focused on protein-truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, here we show that rare PTVs in the p53-inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and ovarian cancer. PPM1D PTV mutations were present in 25 out of 7,781 cases versus 1 out of 5,861 controls (P = 1.12 × 10-5), including 18 mutations in 6,912 individuals with breast cancer (P = 2.42 × 10-4) and 12 mutations in 1,121 individuals with ovarian cancer (P = 3.10 × 10-9). Notably, all of the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370-base-pair region in the final exon of the gene, carboxy-terminal to the phosphatase catalytic domain. Functional studies demonstrate that the mutations result in enhanced suppression of p53 in response to ionizing radiation exposure, suggesting that the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function effect typically associated with this class of variant, but instead probably have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the use of sequencing in their identification.
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The androgen receptor (AR) mediates the effects of the male sex-steroid hormones (androgens), testosterone and 5?-dihydrotestosterone. Androgens are critical in the development and maintenance of male sexual characteristics. AR is a member of the steroid receptor ligand-inducible transcription factor family. The steroid receptor family is a subgroup of the nuclear receptor superfamily that also includes receptors for the active forms of vitamin A, vitamin D3, and thyroid hormones. Like all nuclear receptors, AR has a conserved modular structure consisting of a non-conserved amino-terminal domain (NTD), containing the intrinsic activation function 1, a highly conserved DNA-binding domain, and a conserved ligand-binding domain (LBD) that harbors the activation function 2. Each of these domains plays an important role in receptor function and signaling, either via intra- and inter-receptor interactions, interactions with specific DNA sequences, termed hormone response elements, or via functional interactions with domain-specific proteins, termed coregulators (coactivators and corepressors). Upon binding androgens, AR acquires a new conformational state, translocates to the nucleus, binds to androgen response elements, homodimerizes and recruits sequence-specific coregulatory factors and the basal transcription machinery. This set of events is required to activate gene transcription (expression). Gene transcription is a strictly modulated process that governs cell growth, cell homeostasis, cell function and cell death. Disruptions of AR transcriptional activity caused by receptor mutations and/or altered coregulator interactions are linked to a wide spectrum of androgen insensitivity syndromes, and to the pathogenesis of prostate cancer (CaP). The treatment of CaP usually involves androgen depletion therapy (ADT). ADT achieves significant clinical responses during the early stages of the disease. However, under the selective pressure of androgen withdrawal, androgen-dependent CaP can progress to an androgen-independent CaP. Androgen-independent CaP is invariably a more aggressive and untreatable form of the disease. Advancing our understanding of the molecular mechanisms behind the switch in androgen-dependency would improve our success of treating CaP and other AR related illnesses. This study evaluates how clinically identified AR mutations affect the receptor s transcriptional activity. We reveal that a potential molecular abnormality in androgen insensitivity syndrome and CaP patients is caused by disruptions of the important intra-receptor NTD/LBD interaction. We demonstrate that the same AR LBD mutations can also disrupt the recruitment of the p160 coactivator protein GRIP1. Our investigations reveal that 30% of patients with advanced, untreated local CaP have somatic mutations that may lead to increases in AR activity. We report that somatic mutations that activate AR may lead to early relapse in ADT. Our results demonstrate that the types of ADT a CaP patient receives may cause a clustering of mutations to a particular region of the receptor. Furthermore, the mutations that arise before and during ADT do not always result in a receptor that is more active, indicating that coregulator interactions play a pivotal role in the progression of androgen-independent CaP. To improve CaP therapy, it is necessary to identify critical coregulators of AR. We screened a HeLa cell cDNA library and identified small carboxyl-terminal domain phosphatase 2 (SCP2). SCP2 is a protein phosphatase that directly interacts with the AR NTD and represses AR activity. We demonstrated that reducing the endogenous cellular levels of SCP2 causes more AR to load on to the prostate specific antigen (PSA) gene promoter and enhancer regions. Additionally, under the same conditions, more RNA polymerase II was recruited to the PSA promoter region and overall there was an increase in androgen-dependent transcription of the PSA gene, revealing that SCP2 could play a role in the pathogenesis of CaP.
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Plants are rooted to their growth place; therefore it is important that they react adequately to changes in environmental conditions. Stomatal pores, which are formed of a pair of guard cells in leaf epidermis, regulate plant gas-exchange. Importantly, guard cells protect the plant from desiccation in drought conditions by reducing the aperture of the stomatal pore. They serve also as the first barrier against the major air pollutant ozone, but the behaviour of guard cells during ozone exposure has not been sufficiently addressed. Aperture of the stomatal pore is regulated by the influx and efflux of osmotically active ions via ion channels and transporters across the guard cell membrane, however the molecular identity of guard cell plasma membrane anion channel has remained unknown. In the frame of this study, guard cell behaviour during ozone exposure was studied using the newly constructed Arabidopsis whole-rosette gas-exchange system. Ozone induced a Rapid Transient Decrease (RTD) in stomatal conductance within 10 min from the start of exposure, which was followed by a recovery in the conductance within the next 40 min. The decrease in stomatal conductance was dependent on the applied ozone concentration. Three minutes of ozone exposure was sufficient to induce RTD and further ozone application during the closure-recovery process had no effect on RTD, demonstrating that the whole process is programmed within the first three minutes. To address the molecular components responsible for RTD, the ozone response was measured in 59 different Arabidopsis mutants involved in guard cell signalling. Four of the tested mutants slac1 (originally rcd3), ost1, abi1-1 and abi2-1 lacked RTD completely. As the ozone sensitive mutant slac1 lacked RTD, the next aim of this study was to identify and characterize SLAC1. SLAC1 was shown to be a central regulator in response to all major factors regulating guard cell aperture: CO2, light/darkness transitions, ozone, relative air humidity, ABA, NO, H2O2, and extracellular Ca2+. It encodes the first guard cell plasma membrane slow type anion channel to be identified at the molecular level. Interestingly, the rapid type anion conductance was intact in slac1 mutant plants. For activation, SLAC1 needs to be phosphorylated. Protein kinase OST1 was shown to phosphorylate several amino acids in the N-terminal tail of SLAC1, Ser120 was one of its main targets, which led to SLAC1 activation. The lack of RTD in type 2C protein phosphatase mutants abi1-1 and abi2-1, suggests that these proteins have a regulatory role in ozoneinduced activation of the slow type anion channel.
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The tight junction protein claudin-1 (CLDN1) is necessary for hepatitis C virus (HCV) entry into target cells. Recent studies have made disparate observations of the modulation of the expression of CLDN1 on cells following infection by HCV. In one study, the mean CLDN1 expression on cells exposed to HCV declined, whereas in another study HCV infected cells showed increased CLDN1 expression compared to uninfected cells. Consequently, the role of HCV in modulating CLDN1 expression, and hence the frequency of cellular superinfection, remains unclear. Here, we present a possible reconciliation of these disparate observations. We hypothesized that viral kinetics and not necessarily HCV-induced receptor modulation underlies these disparate observations. To test this hypothesis, we constructed a mathematical model of viral kinetics in vitro that mimicked the above experiments. Model predictions provided good fits to the observed evolution of the distribution of CLDN1 expression on cells following exposure to HCV. Cells with higher CLDN1 expression were preferentially infected and outgrown by cells with lower CLDN1 expression, resulting in a decline of the mean CLDN1 expression with time. At the same time, because the susceptibility of cells to infection increased with CLDN1 expression, infected cells tended to have higher CLDN1 expression on average than uninfected cells. Our study thus presents an explanation of the disparate observations of CLDN1 expression following HCV infection and points to the importance of considering viral kinetics in future studies of receptor expression on cells exposed to HCV.
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The bacterial second messenger cyclic diguanosine monophosphate (c-di-GMP) plays an important role in a variety of cellular functions, including biofilm formation, alterations in the cell surface, host colonization and regulation of bacterial flagellar motility, which enable bacteria to survive changing environmental conditions. The cellular level of c-di-GMP is regulated by a balance between opposing activities of diguanylate cyclases (DGCs) and cognate phosphodiesterases (PDE-As). Here, we report the presence and importance of a protein, MSDGC-1 (an orthologue of Rv1354c in Mycobacterium tuberculosis), involved in c-di-GMP turnover in Mycobacterium smegmatis. MSDGC-1 is a multidomain protein, having GAF, GGDEF and EAL domains arranged in tandem, and exhibits both c-di-GMP synthesis and degradation activities. Most other proteins containing GGDEF and EAL domains have been demonstrated to have either DGC or PDE-A activity. Unlike other bacteria, which harbour several copies of the protein involved in c-di-GMP turnover, M. smegmatis has a single genomic copy, deletion of which severely affects long-term survival under conditions of nutrient starvation. Overexpression of MSDGC-1 alters the colony morphology and growth profile of M. smegmatis. In order to gain insights into the regulation of the c-di-GMP level, we cloned individual domains and tested their activities. We observed a loss of activity in the separated domains, indicating the importance of full-length MSDGC-1 for controlling bifunctionality.
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In this study we determined the molecular mechanisms of how homocysteine differentially affects receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG) synthesis in the bone. The results showed that oxidative stress induced by homocysteine deranges insulin-sensitive FOXO1 and MAP kinase signaling cascades to decrease OPG and increase RANKL synthesis in osteoblast cultures. We observed that downregulation of insulin/FOXO1 and p38 MAP kinase signaling mechanisms due to phosphorylation of protein phosphatase 2 A (PP2A) was the key event that inhibited OPG synthesis in homocysteine-treated osteoblast cultures. siRNA knockdown experiments confirmed that FOXO1 is integral to OPG and p38 synthesis. Conversely homocysteine increased RANKL synthesis in osteoblasts through c-Jun/JNK MAP kinase signaling mechanisms independent of FOXO1. In the rat bone milieu, high-methionine diet-induced hyperhomocysteinemia lowered FOXO1 and OPG expression and increased synthesis of proresorptive and inflammatory cytokines such as RANKL, M-CSF, IL-1 alpha, IL-1 beta, G-CSF, GM-CSF, MIP-1 alpha, IFN-gamma, IL-17, and TNF-alpha. Such pathophysiological conditions were exacerbated by ovariectomy. Lowering the serum homocysteine level by a simultaneous supplementation with N-acetylcysteine improved OPG and FOXO1 expression and partially antagonized RANKL and proresorptive cytokine synthesis in the bone milieu. These results emphasize that hyperhomocysteinemia alters the redox regulatory mechanism in the osteoblast by activating PP2A and deranging FOXO1 and MAPK signaling cascades, eventually shifting the OPG:RANKL ratio toward increased osteoclast activity and decreased bone quality (C) 2013 Elsevier Inc. All rights reserved.
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C-di-GMP Bis-(3'-5')-cyclic-dimeric-guanosine monophosphate], a second messenger is involved in intracellular communication in the bacterial species. As a result several multi-cellular behaviors in both Gram-positive and Gram-negative bacteria are directly linked to the intracellular level of c-di-GMP. The cellular concentration of c-di-GMP is maintained by two opposing activities, diguanylate cyclase (DGC) and phosphodiesterase (PDE-A). In Mycobacterium smegmatis, a single bifunctional protein MSDGC-1 is responsible for the cellular concentration of c-di-GMP. A better understanding of the regulation of c-di-GMP at the genetic level is necessary to control the function of above two activities. In this work, we have characterized the promoter element present in msdgc-1 along with the + 1 transcription start site and identified the sigma factors that regulate the transcription of msdgc-1. Interestingly, msdgc-1 utilizes SigA during the initial phase of growth, whereas near the stationary phase SigB containing RNA polymerase takes over the expression of msdgc-1. We report here that the promoter activity of msdgc-1 increases during starvation or depletion of carbon source like glucose or glycerol. When msdgc-1 is deleted, the numbers of viable cells are similar to 10 times higher in the stationary phase in comparison to that of the wild type. We propose here that msdgc-1 is involved in the regulation of cell population density. (C) 2013 Elsevier B.V. All rights reserved.
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The use of titania nanotubes (TiO2-NT) as the working electrode provides a substantial improvement in the electrochemical detection of proteins. A biosensor designed using this strategy provided a robust method to detect protein samples at very low concentrations (C-protein ca 1 ng/mu l). Reproducible measurements on protein samples at this concentration (I-p,I-a of 80 +/- 1.2 mu A) could be achieved using a sample volume of ca 30 mu l. We demonstrate the feasibility of this strategy for the accurate detection of penicillin binding protein, PBP2a, a marker for methicillin resistant Staphylococcus aureus (MRSA). The selectivity and efficiency of this sensor were also validated using other diverse protein preparations such as a recombinant protein tyrosine phosphatase (PTP10D) and bovine serum albumin (BSA). This electrochemical method also presents a substantial improvement in the time taken (few minutes) when compared to conventional enzyme-linked immunosorbent assay (ELISA) protocols. It is envisaged that this sensor could substantially aid in the rapid diagnosis of bacterial infections in resource strapped environments. (C) 2014 Elsevier B.V. All rights reserved.
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Statins are known to modulate cell surface cholesterol (CSC) and AMP-activated protein kinase (AMPK) in nonneural cells; however no study demonstrates whether CSC and AMPK may regulate simvastatin induced neuritogenesis (SIN). We found that simvastatin (SIM) maintains CSC as shown by Fillipin III staining, Flotillin-2 protein expression / localization and phosphorylation of various receptor tyrosine kinases (RTKs) in the plasma membrane. Modulation of CSC revealed that SIN is critically dependent on this CSC. Simultaneously, phospho array for mitogen activated protein kinases (MAPKs) revealed PI3K / Akt as intracellular pathway which modulates lipid pathway by inhibiting AMPK activation. Though, SIM led to a transient increase in AMPK phosphorylation followed by a sudden decline; the effect was independent of PI3K. Strikingly, AMPK phosphorylation was regulated by protein phosphatase 2A (PP2A) activity which was enhanced upon SIM treatment as evidenced by increase in threonine phosphorylation. Moreover, it was observed that addition of AMP analogue and PP2A inhibitor inhibited SIN. Biocomposition of neurites shows that lipids form a major part of neurites and AMPK is known to regulate lipid metabolism majorly through acetyl CoA carboxylase (ACC). AMPK activity is negative regulator of ACC activity and we found that phosphorylation of ACC started to decrease after 6 hrs which becomes more pronounced at 12 hrs. Addition of ACC inhibitor showed that SIN is dependent on ACC activity. Simultaneously, addition of Fatty acid synthase (FAS) inhibitor confirmed that endogenous lipid pathway is important for SIN. We further investigated SREBP-1 pathway activation which controls ACC and FAS at transcriptional level. However, SIM did not affect SREBP-1 processing and transcription of its target genes likes ACC1 and FAS. In conclusion, this study highlights a distinct role of CSC and ACC in SIN which might have implication in process of neuronal differentiation induced by other agents.
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Objectives:To determine if there is a biological mechanism that explains the association between HIV disease progression and increased mortality with low circulating vitamin D levels; specifically, to determine if restoring vitamin D levels induced T-cell functional changes important for antiviral immunity.Design:This was a pilot, open-label, three-arm prospective phase 1 study.Methods:We recruited 28 patients with low plasma vitamin D (<50nmol/l 25-hydroxyvitamin D3), comprising 17 HIV+ patients (11 on HAART, six treatment-naive) and 11 healthy controls, who received a single dose of 200000IU oral cholecalciferol. Advanced T-cell flow cytometry methods measured CD4(+) T-cell function associated with viral control in blood samples at baseline and 1-month after vitamin D supplementation.Results:One month of vitamin D supplementation restored plasma levels to sufficiency (>75nmol/l) in 27 of 28 patients, with no safety issues. The most striking change was in HIV+ HAART+ patients, where increased frequencies of antigen-specific T cells expressing macrophage inflammatory protein (MIP)-1 - an important anti-HIV blocking chemokine - were observed, with a concomitant increase in plasma MIP-1, both of which correlated significantly with vitamin D levels. In addition, plasma cathelicidin - a vitamin D response gene with broad antimicrobial activity - was enhanced.Conclusion:Vitamin D supplementation modulates disease-relevant T-cell functions in HIV-infected patients, and may represent a useful adjunct to HAART therapy. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.
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A asma é uma doença inflamatória crônica caracterizada por hiper-reatividade das vias aéreas, acúmulo de eosinófilos, secreção de muco e remodelamento. No decorrer do estabelecimento do processo inflamatório, há liberação de mediadores endógenos que atuam limitando a evolução do quadro patológico e garantindo a manutenção da homeostasia (COHN, ELIAS e CHUPP, 2004). Dentre estes recebem destaque os hormônios glicocorticóides, reconhecidos por sua atividade anti-inflamatória, dependente, em parte, da geração de fatores intermediários como a proteína anexina-1 (AnxA1) (KAMAL, FLOWER e PERRETTI, 2005; PERRETTI, 2003). Neste estudo investigou-se o papel regulatório da AnxA1 e do peptídeo derivado Ac2-26 (50 - 200 g/animal) no modelo experimental de asma alérgica murina. Camundongos BALB/c (AnxA1+/+) e depletados do gene codificante para AnxA1 (AnxA1-/-) foram sensibilizados com ovoalbumina (OVA 50 g) e hidróxido de alumínio (5 mg), por via subcutânea. Após 14 dias, foi feito reforço com OVA (25 g), por via intraperitoneal, e nos dias 19, 20 e 21 foram desafiados com OVA (25 g), por via intranasal. O tratamento consistiu na administração intranasal do peptídeo Ac2-26 (50 - 200 g), 1 h antes de cada desafio. As análises foram feitas 24 h após o último desafio e incluíram: i) função pulmonar (resistência e elastância) e hiper-reatividade das vias aéreas à metacolina (3 27 mg/ml) através de pletismografia invasiva; ii) alterações morfológicas através de histologia clássica; iii) quantificação de colágeno e iv) quantificação de mediadores inflamatórios através de ELISA. Verificou-se que camundongos AnxA1-/-, quando ativamente sensibilizados e desafiados com OVA apresentaram exacerbação do quadro de hiper-reatividade das vias aéreas, assim como do número de eosinófilos no lavado broncoalveolar e no infiltrado peribrônquico, deposição de colágeno e nos níveis de IL-13 em comparação aos controles AnxA1+/+. Em paralelo, observou-se que o peptídeo Ac2-26 levou a uma redução da hiper-reatividade das vias aéreas frente à estimulação com metacolina nos animais AnxA1+/+. O peptídeo Ac2-26 reduziu o infiltrado inflamatório no parênquima pulmonar e o número de eosinófilos peribronquiolares, além da produção de muco no tecido pulmonar e da geração IL-4, IL-13, eotaxina-1 e -2. Em conjunto, nossos achados mostram que os camundongos AnxA1-/- mostraram-se mais responsivos à estimulação antigênica, o que foi indicativo de que a AnxA1 parece exercer um papel regulatório importante sobre a resposta inflamatória alérgica murina. Além disso, o efeito inibitório do peptídeo Ac2-26 sobre a resposta alérgica pulmonar foi indicativo de que este se coloca como um composto anti-inflamatório e anti-alérgico promissor para utilização na terapia da asma.
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Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-fa
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The objective of this study was to develop soy protein fortified fish sticks from Tilapia. Two preliminary studies were conducted to select the best fish-soy protein-spice mixture combination with four treatments to develop breaded fish sticks. Developed products were organoleptically assessed using 30 untrained panellists with 7-point hedonic scale. The product developed with new combination was compared with market product. Sixty percent of Tilapia fish mince, 12% of Defatted Textured Soy protein (DTSP), 1.6% of salt and 26.4% of ice water (<5°C) and Spice mixture containing 3g of garlic, 2g of pepper 2g of onion and 1.6g of cinnamon were selected as the best formula to manufacture the product. There was no significant difference when compared with market samples in relation to the organoleptic attributes. Proximate composition of the product was 25.76% of crude protein, 2.38% of crude fat, 60.35% of moisture and2.75% of ash. Products were packaged in Poly Vinyl Chloride clear package (12 gauge) and were stored at -1°C and changes in moisture content, peroxide value, pH value and microbiological parameters were assessed during five weeks of storage. Organoleptic acceptability was not changed significantly in all parameters tested (p>0.05). Total aerobic count and yeast and mould count were in acceptable ranges in frozen storage for 5 weeks. Data were analyzed using AN OVA and Friedman non-parametric test.
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Ochotona curzoniae and Microtus oeconomus are the native mammals living on the Qinghai-TibetanPlateau of China. The molecular mechanisms of their acclimatization to the Plateau-hypoxia remain unclear. Expressions of hepatic hypoxia-inducible factor (HIF)-1 alpha, insulin-like growth factor-I (IGF-I)/IGF binding protein (BP)-1(IGFBP-1; including genes), and key metabolic enzymatic genes [lactate dehydrogenase (LDH)-A/isocitrate dehydrogenase (ICD)] are compared in Qinghai-Tibetan- Plateau mammals andsea- level mice after injection of CoCl2 (20, 40, or 60 mg/ kg) and normobaric hypoxia (16.0% O-2, 10.8% O-2, and 8.0% O-2) for 6 h, tested by histochemistry, Western blot analysis, ELISA, and RT-PCR. Major results are CoCl2 markedly increased 1) HIF-1 alpha only in mice, 2) hepatic and circulatory IGF-I in M. oeconomus, 3) hepatic IGFBP-1 in mice and O. curzoniae, and 4) LDH-A but reduced ICD mRNA in mice (CoCl2 20 mg/kg) but were unchanged in the Tibetan mammals. Normobaric hypoxia markedly 1) increased HIF-1 alpha and LDH-A mRNA in mice and M. oeconomus (8.0% O-2) not in O. curzoniae, and 2) reduced ICD mRNA in mice and M. oeconomus (8.0% O-2) not in O. curzoniae. Results suggest that 1) HIF-1 alpha responsiveness to hypoxia is distinct in lowland mice and plateau mammals, reflecting a diverse tolerance of the three species to hypoxia; 2) CoCl2 induces diversities in HIF-1, IGF-I/IGFBP-1 protein or genes in mice, M. oeconomus, and O. curzoniae. In contrast, HIF-1 mediates IGFBP-1 transcription only in mice and in M. oeconomus (subjected to severe hypoxia); 3) differences in IGF-I/IGFBP-1 expressions induced by CoCl2 reflect significant diversities in hormone regulation and cell protection from damage; and 4) activation of anaerobic glycolysis and reduction of Krebs cycle represents strategies of lowland-animals vs. the stable metabolic homeostasis of plateau- acclimatized mammals.