963 resultados para Liver and ethanol


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The benefit of polymeric immuno-nanoparticles (NPs-Tx-HER), consisting of paclitaxel (Tx)-loaded nanoparticles coated with anti-HER2 monoclonal antibodies (Herceptin, trastuzumab), in cancer treatment was assessed in a disseminated xenograft ovarian cancer model induced by intraperitoneal inoculation of SKOV-3 cells overexpressing HER2 antigens. The study was focused on the evaluation of therapeutic efficacy and biodistribution of NPs-Tx-HER compared to other Tx formulations. The therapeutic efficacy was determined by two methods: bioluminescence imaging and survival rate. The treatment regimen consisted in an initial dose of 20mg/kg Tx administered as 10mg/kg intravenously (IV) and 10mg/kg intraperitonealy (IP), followed by five alternative IP and IV injections of 10mg/kg Tx every 3 days. The bioluminescence study has clearly shown the superior anti-tumor activity of NPs-Tx-HER compared to free Tx. As a confirmation of these results, a significantly longer survival of mice was observed for NPs-Tx-HER treatment compared to free Tx, Tx-loaded nanoparticles coated with an irrelevant mAb (Mabthera, rituximab) or Herceptin alone, indicating the potential of immuno-nanoparticles in cancer treatment. The biodistribution pattern of Tx was assessed on healthy and tumor bearing mice after IV or IP administration. An equivalent biodistribution profile was observed in healthy mice for Tx encapsulated either in uncoated nanoparticles (NPs-Tx) or in NPs-Tx-HER. No significant difference in Tx biodistribution was observed after IV or IP injection, except for a lower accumulation in the lungs when NPs were administered by IP. Encapsulated Tx accumulated in the organs of the reticulo-endothelial system (RES) such as the liver and spleen, whereas free Tx had a non-specific distribution in all tested organs. Compared to free Tx, the single dose injection (IV or IP) of encapsulated Tx in mice bearing tumors induced a higher tumor accumulation. However, no difference in overall tumor accumulation between NPs-Tx-HER and NPs-Tx was observed. In conclusion, the encapsulation of Tx into NPs-Tx-HER immuno-nanoparticles resulted in an improved efficacy of drug in the treatment of disseminated ovarian cancer overexpressing HER2 receptors.

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Background and Aims: The impact of d iagnostic delay ( a period from appearance of f irst s ymptoms t o diagnosis) o n the clinical c ourse o f Crohn's disease (CD) i s unknown. W e examined whether length of d iagnostic delay a ffects d isease outcome. Methods: Data from the Swiss IBD cohort study were analyzed. T he frequencies of o ccurrence of b owel s tenoses, internal fistulas, perianal f istulas, and CD-related surgery at distinct i ntervals a fter C D diagnosis (0 - < 2 , 2 - < 6,  6 years) were c ompared f or g roups o f patients w ith different length of d iagnostic delay. Results: T he data from a g roup o f 200 CD patients with long diagnostic delay (> 24 months, 76th - 100th p ercentile) were c ompared to t hose from a group of 4 61 patients with a short diagnostic delay ( within 9 months, 1st - 50th p ercentile). T reatment r egimens d id n ot d iffer between t he two groups. Two years following diagnosis, p atients with long diagnostic delay presented more frequently with bowel stenoses (25% vs. 13.1%, p = 0.044), internal fistulas (10% vs. 2%, p = 0.018), perianal f istulas ( 20% vs. 8 .1%, p = 0.023) a nd more frequently underwent intestinal surgery (15% vs. 5 .1%, p = 0.024) t han patients with short diagnostic delay. Intestinal surgery was a lso m ore frequently p erformed  6 y ears after diagnosis in t he group with long d iagnostic delay ( 56.2% vs. 42.3%, p = 0.005) w hen compared to t he g roup with short diagnostic delay. Conclusions: L ong diagnostic delay i s associated with worse o utcome c haracterized by t he development o f increased bowel damage, n ecessitating more frequently operations in t he years following CD d iagnosis. Efforts should be undertaken to shorten the diagnostic delay.

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Obesity is an excess of fat mass. Fat mass is an energy depot but also an endocrine organ. A deregulation of the sympathetic nervous system (SNS) might produce obesity. Stress exaggerates diet-induced obesity. After stress, SNS fibers release neuropeptide Y (NPY) which directly increases visceral fat mass producing a metabolic syndrome (MbS)-like phenotype. Adrenergic receptors are the main regulators of lipolysis. In severe obesity, we demonstrated that the adrenergic receptor subtypes are differentially expressed in different fat depots. Liver and visceral fat share a common sympathetic pathway, which might explain the low-grade inflammation which simultaneously occurs in liver and fat of the obese with MbS. The neuroendocrine melanocortinergic system and gastric ghrelin are also greatly deregulated in obesity. A specific mutation in the type 4 melanocortin receptor induces early obesity onset, hyperphagia and insulin-resistance. Nonetheless, it was recently discovered that a mutation in the prohormone convertase 1/3 simultaneously produces severe gastrointestinal dysfunctions and obesity.

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The measurement of fat balance (fat input minus fat output) involves the accurate estimation of both metabolizable fat intake and total fat oxidation. This is possible mostly under laboratory conditions and not yet in free-living conditions. In the latter situation, net fat retention/mobilization can be estimated based on precise and accurate sequential body composition measurements. In case of positive balance, lipids stored in adipose tissue can originate from dietary (exogenous) lipids or from nonlipid precursors, mainly from carbohydrates (CHOs) but also from ethanol, through a process known as de novo lipogenesis (DNL). Basic equations are provided in this review to facilitate the interpretation of the different subcomponents of fat balance (endogenous vs exogenous) under different nutritional circumstances. One difficulty is methodological: total DNL is difficult to measure quantitatively in man; for example, indirect calorimetry only tracks net DNL, not total DNL. Although the numerous factors (mostly exogenous) influencing DNL have been studied, in particular the effect of CHO overfeeding, there is little information on the rate of DNL in habitual conditions of life, that is, large day-to-day fluctuations of CHO intakes, different types of CHO ingested with different glycemic indexes, alcohol combined with excess CHO intakes, etc. Three issues, which are still controversial today, will be addressed: (1) Is the increase of fat mass induced by CHO overfeeding explained by DNL only, or by decreased endogenous fat oxidation, or both? (2) Is DNL different in overweight and obese individuals as compared to their lean counterparts? (3) Does DNL occur both in the liver and in adipose tissue? Recent studies have demonstrated that acute CHO overfeeding influences adipose tissue lipogenic gene expression and that CHO may stimulate DNL in skeletal muscles, at least in vitro. The role of DNL and its importance in health and disease remain to be further clarified, in particular the putative effect of DNL on the control of energy intake and energy expenditure, as well as the occurrence of DNL in other tissues (such as in myocytes) in addition to hepatocytes and adipocytes.

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Stable protein-DNA complexes can be assembled in vitro at the 5' end of Xenopus laevis vitellogenin genes using extracts of nuclei from estrogen-induced frog liver and visualized by electron microscopy. Complexes at the three following sites can be identified on the gene B2: the transcription initiation site, the estrogen responsive element (ERE) and in the first intron. The complex at the transcription initiation site is stabilized by dinucleotides and thus represents a ternary transcription complex. The formation of the complexes at the two other sites is enhanced by estrogen and is reduced by tamoxifen, an antagonist of estrogen, while this latter effect is reversed by adding an excess of hormone. No sequence homology is apparent between the site containing the ERE and the binding site in intron I and functional tests in MCF-7 cells suggest that these two sites are not equivalent. Finally, we made use of previously characterized deletion mutants of the 5' flanking region of the gene B1, a close relative of the gene B2, to demonstrate that the 13-bp palindromic core element of the ERE is involved in the formation of the complexes observed upstream of the transcription initiation site.

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BACKGROUND: The envelope glycoprotein of lymphocytic choriomeningitis virus (LCMV) can efficiently pseudotype lentiviral vectors. Some strains of LCMV exploit high affinity interactions with α-dystroglycan (α-DG) to bind to cell surfaces and subsequently fuse in low pH endosomes. LCMV strains with low α-DG affinity utilize an unknown receptor and display unique tissue tropisms. We pseudotyped non-primate feline immunodeficiency virus (FIV) vectors using LCMV derived glycoproteins with high or low affinity to α-DG and evaluated their properties in vitro and in vivo. METHODS: We pseudotyped FIV with the LCMV WE54 strain envelope glycoprotein and also engineered a point mutation in the WE54 envelope glycoprotein (L260F) to diminish α-DG affinity and direct binding to alternate receptors. We hypothesized that this change would alter in vivo tissue tropism and enhance gene transfer to neonatal animals. RESULTS: In mice, hepatic α- and β-DG expression was greatest at the late gestational and neonatal time points. When displayed on the surface of the FIV lentivirus the WE54 L260F mutant glycoprotein bound weakly to immobilized α-DG. Additionally, LCMV WE54 pseudotyped FIV vector transduction was neutralized by pre-incubation with soluble α-DG, while the mutant glycoprotein pseudotyped vector was not. In vivo gene transfer in adult mice with either envelope yielded low transduction efficiencies in hepatocytes following intravenous delivery. In marked contrast, neonatal gene transfer with the LCMV envelopes, and notably with the FIV-L260F vector, conferred abundant liver and lower level cardiomyocyte transduction as detected by luciferase assays, bioluminescent imaging, and β-galactosidase staining. CONCLUSIONS: These results suggest that a developmentally regulated receptor for LCMV is expressed abundantly in neonatal mice. LCMV pseudotyped vectors may have applications for neonatal gene transfer. ABBREVIATIONS: Armstrong 53b (Arm53b); baculovirus Autographa californica GP64 (GP64); charge-coupled device (CCD); dystroglycan (DG); feline immunodeficiency virus (FIV); glycoprotein precursor (GP-C); firefly luciferase (Luc); lymphocytic choriomeningitis virus (LCMV); nuclear targeted β-galactosidase (ntLacZ); optical density (OD); PBS/0.1% (w/v) Tween-20 (PBST); relative light units (RLU); Rous sarcoma virus (RSV); transducing units per milliliter (TU/ml); vesicular stomatitis virus (VSV-G); wheat germ agglutinin (WGA); 50% reduction in binding (C50).

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The objective of this study was to evaluate the plasma concentrations of insulin-like growth factor-I (IGF-I), and the mRNA hepatic expression of IGF-I and of the growth hormone receptors GHR and GHR 1A, in postpartum beef cows. Four Angus and four crossbred (Angus x Nelore) postpartum suckled beef cows were used. Liver and blood samples were collected every 10 days, from calving to 40 days postpartum, for gene expression and for β-hydroxybutyrate and IGF-I assays, respectively. Samples for progesterone assay were collected every other day, from day 10 to 40 postpartum. Three cows ovulated before 40 days postpartum. IGF-I concentration was higher in Angus x Nelore than in Angus cows. There was no difference in the expression of GHR, GHR 1A and IGF-I according to breed or ovulatory status. IGF-I concentrations were higher in crossbred cows, but have not changed according to postpartum ovulatory status. Moreover, changes in postpartum IGF-I concentrations are not associated with changes in liver GHR, GHR 1A and IGF-I mRNA expression in either breed.

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PPARs are members of the nuclear hormone receptor superfamily and are primarily involved in lipid metabolism. The expression patterns of all 3 PPAR isotypes in 22 adult rat organs were analyzed by a quantitative ribonuclease protection assay. The data obtained allowed comparison of the expression of each isotype to the others and provided new insight into the less studied PPAR beta (NR1C2) expression and function. This isotype shows a ubiquitous expression pattern and is the most abundant of the three PPARs in all analyzed tissues except adipose tissue. Its expression is especially high in the digestive tract, in addition to kidney, heart, diaphragm, and esophagus. After an overnight fast, PPAR beta mRNA levels are dramatically down-regulated in liver and kidney by up to 80% and are rapidly restored to control levels upon refeeding. This tight nutritional regulation is independent of the circulating glucocorticoid levels and the presence of PPAR alpha, whose activity is markedly up-regulated in the liver and small intestine during fasting. Finally, PPAR gamma 2 mRNA levels are decreased by 50% during fasting in both white and brown adipose tissue. In conclusion, fasting can strongly influence PPAR expression, but in only a few selected tissues.

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There has been much concern regarding the role of dietary fructose in the development of metabolic diseases. This concern arises from the continuous increase in fructose (and total added caloric sweeteners consumption) in recent decades, and from the increased use of high-fructose corn syrup (HFCS) as a sweetener. A large body of evidence shows that a high-fructose diet leads to the development of obesity, diabetes, and dyslipidemia in rodents. In humans, fructose has long been known to increase plasma triglyceride concentrations. In addition, when ingested in large amounts as part of a hypercaloric diet, it can cause hepatic insulin resistance, increased total and visceral fat mass, and accumulation of ectopic fat in the liver and skeletal muscle. These early effects may be instrumental in causing, in the long run, the development of the metabolic syndrome. There is however only limited evidence that fructose per se, when consumed in moderate amounts, has deleterious effects. Several effects of a high-fructose diet in humans can be observed with high-fat or high-glucose diets as well, suggesting that an excess caloric intake may be the main factor involved in the development of the metabolic syndrome. The major source of fructose in our diet is with sweetened beverages (and with other products in which caloric sweeteners have been added). The progressive replacement of sucrose by HFCS is however unlikely to be directly involved in the epidemy of metabolic disease, because HFCS appears to have basically the same metabolic effects as sucrose. Consumption of sweetened beverages is however clearly associated with excess calorie intake, and an increased risk of diabetes and cardiovascular diseases through an increase in body weight. This has led to the recommendation to limit the daily intake of sugar calories.

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The aim of this study was to evaluate the reliability of insect larvae as samples for toxicological investigations. For this purpose, larvae of Lucilia sericata were reared on samples of minced pig liver treated with different concentrations of codeine: therapeutic, toxic, and potentially lethal doses. Codeine was detected in all tested larvae, confirming the reliability of these specimens for qualitative toxicology analysis. Furthermore, concentrations measured in larvae were correlated with levels in liver tissue. These observations bring new elements regarding the potential use of opiates concentrations in larvae for estimation of drug levels in human tissues. Morphine and norcodeine, two codeine metabolites, have been also detected at different concentrations depending on the concentration of codeine in pig liver and depending on the substance itself. The effects of codeine on the development of L. sericata were also investigated. Results showed that a 29-h interval bias on the evaluation of the larval stage duration calculated from the larvae weight has to be considered if codeine was present in the larvae substrate. Similarly, a 21-h interval bias on the total duration of development, from egg to imago, has to be considered if codeine was present in the larvae substrate.

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Immune responses have the important function of host defense and protection against pathogens. However, the immune response also causes inflammation and host tissue injury, termed immunopathology. For example, hepatitis B and C virus infection in humans cause immunopathological sequel with destruction of liver cells by the host's own immune response. Similarly, after infection with lymphocytic choriomeningitis virus (LCMV) in mice, the adaptive immune response causes liver cell damage, choriomeningitis and destruction of lymphoid organ architecture. The immunopathological sequel during LCMV infection has been attributed to cytotoxic CD8(+) T cells. However, we now show that during LCMV infection CD4(+) T cells selectively induced the destruction of splenic marginal zone and caused liver cell damage with elevated serum alanin-transferase (ALT) levels. The destruction of the splenic marginal zone by CD4(+) T cells included the reduction of marginal zone B cells, marginal zone macrophages and marginal zone metallophilic macrophages. Functionally, this resulted in an impaired production of neutralizing antibodies against LCMV. Furthermore, CD4(+) T cells reduced B cells with an IgM(high)IgD(low) phenotype (transitional stage 1 and 2, marginal zone B cells), whereas other B cell subtypes such as follicular type 1 and 2 and germinal center/memory B cells were not affected. Adoptive transfer of CD4(+) T cells lacking different important effector cytokines and cytolytic pathways such as IFNγ, TNFα, perforin and Fas-FasL interaction did reveal that these cytolytic pathways are redundant in the induction of immunopathological sequel in spleen. In conclusion, our results define an important role of CD4(+) T cells in the induction of immunopathology in liver and spleen. This includes the CD4(+) T cell mediated destruction of the splenic marginal zone with consecutively impaired protective neutralizing antibody responses.

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BACKGROUND: Both nutritional and genetic factors are involved in the pathogenesis of nonalcoholic fatty liver disease and insulin resistance. OBJECTIVE: The aim was to assess the effects of fructose, a potent stimulator of hepatic de novo lipogenesis, on intrahepatocellular lipids (IHCLs) and insulin sensitivity in healthy offspring of patients with type 2 diabetes (OffT2D)--a subgroup of individuals prone to metabolic disorders. DESIGN: Sixteen male OffT2D and 8 control subjects were studied in a crossover design after either a 7-d isocaloric diet or a hypercaloric high-fructose diet (3.5 g x kg FFM(-1) x d(-1), +35% energy intake). Hepatic and whole-body insulin sensitivity were assessed with a 2-step hyperinsulinemic euglycemic clamp (0.3 and 1.0 mU x kg(-1) x min(-1)), together with 6,6-[2H2]glucose. IHCLs and intramyocellular lipids (IMCLs) were measured by 1H-magnetic resonance spectroscopy. RESULTS: The OffT2D group had significantly (P < 0.05) higher IHCLs (+94%), total triacylglycerols (+35%), and lower whole-body insulin sensitivity (-27%) than did the control group. The high-fructose diet significantly increased IHCLs (control: +76%; OffT2D: +79%), IMCLs (control: +47%; OffT2D: +24%), VLDL-triacylglycerols (control: +51%; OffT2D: +110%), and fasting hepatic glucose output (control: +4%; OffT2D: +5%). Furthermore, the effects of fructose on VLDL-triacylglycerols were higher in the OffT2D group (group x diet interaction: P < 0.05). CONCLUSIONS: A 7-d high-fructose diet increased ectopic lipid deposition in liver and muscle and fasting VLDL-triacylglycerols and decreased hepatic insulin sensitivity. Fructose-induced alterations in VLDL-triacylglycerols appeared to be of greater magnitude in the OffT2D group, which suggests that these individuals may be more prone to developing dyslipidemia when challenged by high fructose intakes. This trial was registered at clinicaltrials.gov as NCT00523562.

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Personal results are presented to illustrate the development of immunoscintigraphy for the detection of cancer over the last 12 years, from the early experimental results in nude mice grafted with human colon carcinoma to the most modern form of immunoscintigraphy applied to patients, using I123 labeled Fab fragments from monoclonal anti-CEA antibodies detected by single photon emission computerized tomography (SPECT). The first generation of immunoscintigraphy used I131 labeled, immunoadsorbent purified, polyclonal anti-CEA antibodies and planar scintigraphy, as the detection system. The second generation used I131 labeled monoclonal anti-CEA antibodies and SPECT, while the third generation employed I123 labeled fragments of monoclonal antibodies and SPECT. The improvement in the precision of tumor images with the most recent forms of immunoscintigraphy is obvious. However, we think the usefulness of immunoscintigraphy for routine cancer management has not yet been entirely demonstrated. Further prospective trials are still necessary to determine the precise clinical role of immunoscintigraphy. A case report is presented on a patient with two liver metastases from a sigmoid carcinoma, who received through the hepatic artery a therapeutic dose (100 mCi) of I131 coupled to 40 mg of a mixture of two high affinity anti-CEA monoclonal antibodies. Excellent localisation in the metastases of the I131 labeled antibodies was demonstrated by SPECT and the treatment was well tolerated. The irradiation dose to the tumor, however, was too low at 4300 rads (with 1075 rads to the normal liver and 88 rads to the bone marrow), and no evidence of tumor regression was obtained. Different approaches for increasing the irradiation dose delivered to the tumor by the antibodies are considered.

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Absorption, transport and storage of iron are tightly regulated, as expected for an element, which is both essential and potentially toxic. Iron deficiency is the leading cause of anaemia, and it also compromises immune function and cognitive development. Iron overload damages the liver and other organs in hereditary hemochromatosis, and in thalassaemia patients with both transfusion and non-transfusionrelated iron accumulation. Excess iron has harmful effects in chronic liver diseases caused by excessive alcohol, obesity or viruses. There is evidence for involvement of iron in neurodegenerative diseases and in Type 2 diabetes. Variation in transferrin saturation, a biomarker of iron status, has been associated with mortality in patients with diabetes and in the general population13. All these associations between iron and either clinical disease or pathological processes make it important to understand the causes of variation in iron status. Importantly, information on genetic causes of variation can be used in Mendelian randomization studies to test whether variation in iron status is a cause or consequence of disease. We have used biomarkers of iron status (serum iron, transferrin, transferrin saturation and ferritin), which are commonly used clinically and readily measurable in thousands of individuals, and carried out a meta-analysis of human genomewide association study (GWAS) data from 11 discovery and eight replication cohorts. Our aims were to identify additional loci affecting markers of iron status in the general population and to relate the significant loci to information on gene expression to identify relevant genes. We also made an initial assessment of whether any such loci affect iron status in HFE C282Y homozygotes, who are at genetic risk of HFE-related iron overload (hereditary hemochromatosis type 1, OMIM #235200)

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Adipose tissue (AT) is distributed as large differentiated masses, and smaller depots covering vessels, and organs, as well as interspersed within them. The differences between types and size of cells makes AT one of the most disperse and complex organs. Lipid storage is partly shared by other tissues such as muscle and liver. We intended to obtain an approximate estimation of the size of lipid reserves stored outside the main fat depots. Both male and female rats were made overweight by 4-weeks feeding of a cafeteria diet. Total lipid content was analyzed in brain, liver, gastrocnemius muscle, four white AT sites: subcutaneous, perigonadal, retroperitoneal and mesenteric, two brown AT sites (interscapular and perirenal) and in a pool of the rest of organs and tissues (after discarding gut contents). Organ lipid content was estimated and tabulated for each individual rat. Food intake was measured daily. There was a surprisingly high proportion of lipid not accounted for by the main macroscopic AT sites, even when brain, liver and BAT main sites were discounted. Muscle contained about 8% of body lipids, liver 1-1.4%, four white AT sites lipid 28-63% of body lipid, and the rest of the body (including muscle) 38-44%. There was a good correlation between AT lipid and body lipid, but lipid in"other organs" was highly correlated too with body lipid. Brain lipid was not. Irrespective of dietary intake, accumulation of body fat was uniform both for the main lipid storage and handling organs: large masses of AT (but also liver, muscle), as well as in the"rest" of tissues. These storage sites, in specialized (adipose) or not-specialized (liver, muscle) tissues reacted in parallel against a hyperlipidic diet challenge. We postulate that body lipid stores are handled and regulated coordinately, with a more centralized and overall mechanisms than usually assumed.