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E Crockett

Publications and source records attributed to E Crockett.

6 recordsLinked to original sources

Inhibition of Kupffer cells reduced CXC chemokine production and liver injury.

BACKGROUND: Cytokine production is a critical component of ischemia/reperfusion (IR) injury. In the liver, Kupffer cells produce cytokines and chemokines (i.e., cytokines with chemoattractant properties) that are important mediators in neutrophil recruitment and subsequent hepatocellular injury. Therefore, the role of Kupffer cells in chemokine production in hepatic IR injury was investigated. METHODS: Adult male C57BL/6 mice underwent 90 min of partial hepatic ischemia followed by various reperfusion times (i.e., 0, 1.5, 3, and 6 h). Gadolinium chloride (GC), which inhibits Kupffer cell activity, was administered to mice 48 and 24 h prior to ischemia. The control group received a corresponding volume of normal saline. Plasma levels of the cytokine macrophage inflammatory protein-2 (MIP-2), KC, and tumor necrosis factor (TNF)-alpha and liver mRNA were measured. Liver injury was assessed by plasma level of alanine transaminase (ALT) and histopathology. RESULTS: A reperfusion time-dependent liver injury occurred as indicated by increased levels of plasma ALT and histopathology. The injury was associated with increased plasma TNF-alpha, MIP-2, and KC and their hepatic mRNA expression and neutrophil infiltration into ischemic lobes of the liver. GC treatment significantly reduced the number of Kupffer cells as determined by the immunostained liver tissue sections. The extent of liver injury significantly decreased in GC-treated mice that were associated with decreased levels of plasma ALT, TNF-alpha, MIP-2, and KC and neutrophil infiltration. CONCLUSIONS: This study suggests that Kupffer cells are major contributors to cytokine production in hepatic IR and their modulation may serve as a potential target for therapeutic intervention.

Alanine Transaminase↗

Hepatic ischemia/reperfusion injury in P-selectin and intercellular adhesion molecule-1 double-mutant mice.

Neutrophil adhesion and recruitment represents one of the early cellular events that occur during hepatic ischemia/reperfusion (IR) injury and plays a critical role in determining the extent of tissue damage. The adhesion molecules, such as selectins and intercellular adhesion molecules (ICAM), are important in mediating neutrophil-endothelial cell interactions and neutrophil emigration. The goal of this study was to evaluate the role of P-selectin and ICAM-1 in hepatic IR injury. Male wild-type and P-selectin/ICAM-1-deficient (P/I null) mice underwent 90 minutes of partial hepatic ischemia followed by reperfusion at various time points (0, 1.5, 3, and 6 hours). Reperfusion caused a time-dependent hepatocellular injury in both wild-type and P/I null mice as judged by plasma alanine aminotransferase (ALT) levels and liver histopathology examination. Although ALT levels were slightly lower in the P/I null mice compared with the wild-type mice the differences were not statistically significant. Neutrophil infiltration to the ischemic liver was observed in both mouse groups after 6 hours of reperfusion; however, the infiltration to the midzonal region of the ischemic liver was more pronounced in the wild-type group. This study suggests that hepatocellular injury induced after hepatic IR was independent of P-selectin and ICAM-1 in this model of acute inflammatory tissue injury.

Alanine Transaminase↗

Cholesterol levels explain inverse compensation of membrane order in brush border but not homeoviscous adaptation in basolateral membranes from the intestinal epithelia of rainbow trout

The role of cholesterol in the thermal adaptation of biological membranes is explored. Physical and chemical responses of membranes to acclimation temperature were evaluated using plasma membrane domains (basolateral and brush border) prepared from intestinal epithelia of 5- and 20 °C-acclimated rainbow trout (Oncorhynchus mykiss). Basolateral membranes (BLMs) exhibit perfect homeoviscous efficacy (indicated by fluorescence depolarization using 1,6-diphenyl-1,3,5-hexatriene), although cholesterol content does not change with acclimation temperature (molar ratios of cholesterol to phospholipid are 0.23± 0.01 from 5 °C-acclimated fish and 0.25±0.02 from 20°C-acclimated fish; mean ± s.e.m.). Reductions (greater than 30 %) in each of the two major saturated fatty acids (16:0 and 18:0), and a 42 % increase in the polyunsaturate 22:6 (n-3) are found in BLMs from fish acclimated to 5 °C compared with membranes from warm-acclimated animals, suggesting that the phospholipid acyl chain composition determines the physical properties of BLMs. In marked contrast, brush-border membranes (BBMs) display opposite trends. BBMs from 5 °C-acclimated fish are more ordered than BBMs from 20 °C-acclimated fish (inverse compensation). Cholesterol content expressed relative to protein or relative to total polar lipid (phospholipid plus glycolipid) is significantly higher in cold- than in warm-acclimated fish, and nearly so (P=0.15) relative to phospholipid (0.31±0.03 in 5 °C-acclimated animals and 0.25±0.02 in 20 °C-acclimated animals). Only minor changes in the acyl composition of BBMs are induced by temperature acclimation. These results suggest that bile, a constituent of the apical microenvironment, may impose unusual requirements for membrane order and/or stability in the brush border.

Journal Article↗

[Evolution of serum gammaglutamyl transpeptidase activity in treated hyperthyroid and hypothyroid patients].

The pattern of gammaglutamyl transpeptidase levels was studied in the sera of 25 subjects with hyperthyroidism and 11 subjects with hypothyroidism, before and after treatment, and in 14 age- and sex-matched control subjects. Gammaglutamyl transpeptidase levels were significantly increased in hyperthyroidism (65 +/- 59 U/l) (p less than 0.01) and significantly decreased under treatment (40 +/- 27 U/l) (p less than 0.001). Before treatment, gammaglutamyl transpeptidase levels correlated with alkaline phosphatase levels and 5'-nucleotidase levels, the correlation persisting after treatment with 5'-nucleotidase. Alkaline phosphatase levels significantly increased under treatment (p less than 0.01). The percentages of gammaglutamyl transpeptidase variation correlated with thyroxine (r = 0.44, p less than 0.03), triiodothyronine (r = 0.47, p less than 0.02) and latent fixation capacity (r = 0.44, p less than 0.03) variations. Subjects with hypothyroidism had significantly decreased gammaglutamyl transpeptidase levels before treatment (18 +/- 9 U/l, p less than 0.01). Alkaline phosphatase levels were significantly decreased before treatment, and significantly increased after treatment. For all subjects with hyperthyroidism of hypothyroidism, the percentages of gammaglutamyl transpeptidase variations correlated with thyroxine (r = 0.48, p less than 0.003) and triiodothyronine (r = 0.39, p less than 0.016) variations. These results suggest that variations in gammaglutamyl transpeptidase levels in hyperthyroidism and hypothyroidism are, at least in part, in relation with variations in thyroid hormone levels.

Adult↗

Iron for Children.

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Anemia, Hypochromic↗