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1.
An investigation on the influence of lead toxicity on some of the hepatic enzymes was studied in rats both after a shorter
interval of 15 d and after longer intervals of 60 and 90 d. Three different doses of lead as 5, 10, and 50 mg/kg body wt were
administered orally on every alternate day. Whereas significant inhibition of succinic dehydrogenase was seen following lead
poisoning, the activity acid and alkaline phosphatase increased with lead intoxication. The histoarchitecture of the liver
was grossly intact. Liver accumulated less lead compared to kidney at 60 and 90 d. 相似文献
2.
Ryota Masuzaki Sophia Zhao M. Todd Valerius Daisuke Tsugawa Yuki Oya Kevin C. Ray Seth J. Karp 《The Journal of biological chemistry》2016,291(7):3346-3358
After significant injury, the liver must maintain homeostasis during the regenerative process. We hypothesized the existence of mechanisms to limit hepatocyte proliferation after injury to maintain metabolic and synthetic function. A screen for candidates revealed suppressor of cytokine signaling 2 (SOCS2), an inhibitor of growth hormone (GH) signaling, was strongly induced after partial hepatectomy. Using genetic deletion and administration of various factors we investigated the role of SOCS2 during liver regeneration. SOCS2 preserves liver function by restraining the first round of hepatocyte proliferation after partial hepatectomy by preventing increases in growth hormone receptor (GHR) via ubiquitination, suppressing GH pathway activity. At later times, SOCS2 enhances hepatocyte proliferation by modulating a decrease in serum insulin-like growth factor 1 (IGF-1) that allows GH release from the pituitary. SOCS2, therefore, plays a dual role in modulating the rate of hepatocyte proliferation. In particular, this is the first demonstration of an endogenous mechanism to limit hepatocyte proliferation after injury. 相似文献
3.
Jiefeng He Haichao Zhao Dongfeng Deng Yadong Wang Xiao Zhang Haoliang Zhao Zongquan Xu 《Journal of cellular physiology》2020,235(3):2464-2477
This study aimed to identify significant biomarkers related to the prognosis of liver cancer using long noncoding RNA (lncRNA)-associated competing endogenous RNAs (ceRNAs) analysis. Differentially expressed mRNA and lncRNAs between liver cancer and paracancerous tissues were screened, and the functions of these mRNAs were predicted by gene ontology and pathway enrichment analyses. A ceRNA network consisting of differentially expressed mRNAs and lncRNAs was constructed. LncRNA FENDRR and lncRNA HAND2-AS1 were hub nodes in the ceRNA network. A risk score assessment model consisting of eight genes (PDE2A, ESR1, FBLN5, ALDH8A1, AKR1D1, EHHADH, ADRA1A, and GNE) associated with prognosis were developed. Multivariate Cox regression suggested that both pathologic_T and risk group could be regarded as independent prognostic factors. Furthermore, a nomogram model consisting of pathologic_T and risk group showed a good prediction ability for predicting the survival rate of liver cancer patients. The nomogram model consisting of pathologic_T and a risk score assessment model could be regarded as an independent factor for predicting prognosis of liver cancer. 相似文献
4.
Libo Tan Amanda E. Wray Michael H. Green A. Catharine Ross 《Journal of lipid research》2014,55(6):1077-1086
Vitamin A (VA) metabolism in neonates is virtually uncharacterized. Our objective was to develop a compartmental model of VA metabolism in unsupplemented and VA-supplemented neonatal rats. On postnatal day 4, pups (n = 3/time) received 11,12-[3H]retinol orally, in either oil (control) or VA combined with retinoic acid (VARA) [VA (∼6 mg/kg body weight) + 10% retinoic acid]. Plasma and tissues were collected at 14 time points up to 14 days after dose administration. VARA supplementation rapidly, but transiently, increased total retinol mass in plasma, liver, and lung. It decreased the peak fraction of the dose in plasma. A multi-compartmental model developed to fit plasma [3H]retinol data predicted more extensive recycling of retinol between plasma and tissues in neonates compared with that reported in adults (144 vs. 12–13 times). In VARA pups, the recycling number for retinol between plasma and tissues (100 times) and the time that retinol spent in plasma were both lower compared with controls; VARA also stimulated the uptake of plasma VA into extravascular tissues. A VARA perturbation model indicated that the effect of VARA in stimulating VA uptake into tissues in neonates is both dramatic and transient. 相似文献
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6.
Lodovica Vergani Marina Fanin Andrea Martinuzzi Andrea Galassi Andrea Appi Rosalba Carrozzo Maurizio Rosa Corrado Angelini 《Molecular and cellular biochemistry》1990,98(1-2):225-230
Summary FABPs in the various tissues play an important role in the intracellular fatty acid transport and metabolism. Reye's syndrome (RS) and multisystemic lipid storage (MLS) are human disorders characterized by a disturbance of lipid metabolism of unknown etiology. We investigated for the first time L-FABP in these two conditions. Affinity purified antibodies against chicken L-FABP were raised in rabbits, and found to cross-react specifically with partially purified human L-FABP. L-FABP content in liver samples of two patients with RS and MLS was investigated by immuno-histochemistry, SDS-PAGE and ELISA. L-FABP immuno-histochemistry showed increased reactivity in the liver of RS patient and normal reactivity in MLS liver. L-FABP increase in RS liver was confirmed by densitometry of SDS-PAGE and ELISA method. By these two methods the increase amounted to 180% and 199% (p < 0.02), respectively, as compared to controls. A possible role of L-FABP in the pathogenesis of RS is discussed. 相似文献
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9.
《Bioorganic & medicinal chemistry》2016,24(21):5052-5060
Targeting the interaction between G-Protein Coupled Receptor, CXCR4, and its natural ligand CXCL12 is a leading strategy to mitigate cancer metastasis and reduce inflammation. Several pyridine-based compounds modeled after known small molecule CXCR4 antagonists, AMD3100 and WZ811, were synthesized. Nine hit compounds were identified. These compounds showed lower binding concentrations than AMD3100 (1000 nM) and six of the nine compounds had an effective concentration (EC) less than or equal to WZ811 (10 nM). Two of the hit compounds (2g and 2w) inhibited invasion of metastatic cells at a higher rate than AMD3100 (62%). Compounds 2g and 2w also inhibit inflammation in the same range as WZ811 in the paw edema test at 40% reduction in inflammation. These preliminary results are the promising foundation of a new class of pyridine-based CXCR4 antagonists. 相似文献
10.
L. G. Mukwaya 《Entomologia Experimentalis et Applicata》1986,41(3):203-212
The male blowfly, Phormia regina Meigen shows preference among a variety of natural and artificial foods. In a laboratory study preference was observed among sweet and fermenting juices as well as between liver and fish. The preferences between fresh and fermenting juices were based not only on component sugars, but also on other components, namely, amino acids, alcohol salts and presumably other chemical compounds. The preference between decaying liver and fish was probably based partly on the composition and concentration of amino acids in these foods. A variety of amino acids were found in foods and some of these amino acids were shown to be excitatory, some inhibitory and others neutral. Salts were also observed to be present in the juices; and in a laboratory study NaCl at lower concentrations acted synergestically with 0.1 M sucrose and at higher concentrations repulsive. It is suggested that feeding preference is based on several chemicals which behave either in an excitatory, additive, neutral, inhibitory or synergistic manner. The ratio of excitants to inhibitants is important in deciding the direction of preference.
Résumé P. regina Meigen mâle préfere certains aliments naturels ou artificiels. Au laboratoire ses préférences parmi les jus sucrés sont les suivantes: orange > miel > pomme > sucrose 0.1 M; et parmi les aliments en décomposition: sucrose 0.1 M > foie > poisson. Les jus frais sont préférés aux jus fermentés. Les préférences ne dépendent pas seulement de la nature des sucres, mais aussi des acides aminés, de l'alcool, des sels et probablement d'autres substances chimiques. Le foie contient à la fois le plus grand nombre et la concentration la plus élevée en acides aminés, ce qui explique partiellement le goût pour le foie. Expérimentalement on peut classer les acides aminés en stimulants, inhibiteurs et neutres. Des sels ont été notés dans les jus, mais aucune analyse qualitative et quantitative n'en a été faite. Mélangé à du sucrose à 0.1 M, NaCl agit en synergie aux faibles concentrations, devient neutre à 0.175 M et à des concentrations supérieures le sucrose seul est préféré au mélange avec NaCl. Cependant, un mélange de NaCl à 0.25 M (bien qu'une telle concentration soit peu probable dans des jus végétaux) avec du sucrose à 0.1 M était préféré à l'eau. Il en est déduit que les préférences alimentaires. dans la nature sont orientées par plusieurs substances chimiques qui se comportent d'une façon stimulante, additive, neutre, inhibitrice ou synergique, et que les préférences alimentaires sont relatives. Le rapport de stimulants sur inhibiteurs est important dans la détermination du sens de la préférence.相似文献