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HA Levels (ha + level)

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Medical Sciences100%

Selected Abstracts

Hyaluronan and its receptors in mucoepidermoid carcinoma

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2006
Richard O. Wein MD
Abstract Background. Hyaluronan (HA) is a prominent extracellular matrix component undergoing continuous production and degradation. Increased HA levels have been described in a variety of tumors. The objective of this study was to examine the staining patterns of HA and two of its associated receptors (CD44 and HARE) in relation to the metastatic potential of mucoepidermoid carcinoma (MC). Immunohistochemical staining of preserved surgical specimens was used. Methods. Tissues from 12 patients with a histologic diagnosis of salivary MC (10 parotid, one submandibular gland, one minor salivary gland) were studied. Half (six of 12) of the patients had regional metastases. Tumor, normal salivary tissue, and regional lymph nodes were stained for HA, CD44, and HARE expression. Specimens were graded for staining intensity and a percent of the specimen stained. Results. Normal salivary tissue did not demonstrate epithelial cell surface HA expression, whereas HA was expressed on tumor cells and in regional lymph nodes containing metastases. These differences were both significant using Student's t test (p < .00002, and p < .0022, respectively). Tumors with positive nodes tended to have greater cell surface HA. Decreased expression or downregulation of HARE was also noted in involved lymph nodes. No differences in CD44 expression were seen between primary specimens and lymph nodes. The observed staining patterns for CD44 and HARE were not reflective of the metastatic potential of the primary MC. Conclusions. Increased HA expression was seen on mucoepidermoid carcinoma cells compared with adjacent normal salivary gland epithelium. This observation may assist in explaining the development of regional metastasis in these tumors. We did not identify specific HA, CD44, or HARE staining patterns in primary lesions that were predictive of regional metastases. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source]

Noninvasive serum markers in the diagnosis of structural liver damage in chronic hepatitis C virus infection

LIVER INTERNATIONAL, Issue 9 2006
Edison R. Parise
Abstract: Aim: Several noninvasive markers are being used to assess the structural liver damage in patients with chronic hepatitis C (CHC). We evaluated the capacity of serum hyaluronic acid (HA), aspartate aminotransferase (AST)/ALT ratio, the AST to platelet ratio index (APRI) and ,-glutamyltransferase (GGT) levels to predict the intensity of hepatic fibrosis in patients with CHC. Patients and methods: In a total of 206 hepatitis C virus RNA-positive biopsied patients, AST, ALT, GGT levels, platelet count and serum HA concentration were determined. The APRI was calculated as the ratio of AST to platelets. Results: HA levels were best correlated with disease stage (r=,0.694; P<0.001). In the diagnosis of significant fibrosis (F2,F4), HA levels [AUC=0.879, 95% CI (0.832,0.927)] and APRI [AUC=0.824 (0.772,0.903)] were the markers with the best diagnostic accuracy. These parameters also best identified the presence of cirrhosis (F4), with an AUC of 0.908 (0.868,0.949) for HA and of 0.837 (0.772,0.903) for APRI. Conclusion: Serum HA was the parameter that alone presented the best diagnostic accuracy in the assessment of hepatic fibrosis in CHC. The APRI showed a better diagnostic sensitivity than GGT levels or the AST/ALT ratio. Its simple determination and low cost make this index a valid alternative for the noninvasive staging of CHC. [source]

Biochemical markers of liver fibrosis and lymphocytic piecemeal necrosis in UDCA-treated patients with primary biliary cirrhosis

LIVER INTERNATIONAL, Issue 3 2004
Christophe Corpechot
Abstract: Background/Aim: We have previously shown that the histological stage and severity of lymphocytic piecemeal necrosis (LPN) are independent predictive factors of cirrhosis development in ursodeoxycholic acid (UDCA)-treated patients with primary biliary cirrhosis (PBC). Our aim during this study was to determine whether biochemical parameters classically used in PBC management and measured under UDCA could be considered as reliable surrogate markers for these histological prognostic indices in clinical practice. Method: The study included 153 patients with PBC who had undergone a control liver biopsy after 2 years of UDCA therapy. The relationships between histological and biological features were assessed by variance analysis and logistic regression. The diagnostic value of independent markers was assessed in terms of their sensitivity, specificity, positive predictive value (PPV) and negative value (NPV) and receiver-operating characteristic curves. Results: Two variables were independently associated with extensive fibrosis (i.e. advanced histological stages): serum levels of bilirubin and hyaluronic acid (HA). A fibrosis index ([bilirubin (,mol/l)/14]+[HA (,g/l)/143]) higher than 1.5 exhibited good PPV and specificity (>74%) but rather poor NPV and sensitivity (<64%) regarding a diagnosis of extensive fibrosis. The only independent marker of LPN was aspartate aminotransferase (AST) activity. AST activity of more than twice the upper limit of normal showed acceptable PPV (>70%) but very low sensitivity (<25%) for a diagnosis of LPN. Conclusions: Serum bilirubin and HA levels measured under UDCA therapy are of acceptable diagnostic value for extensive fibrosis, but none of the biochemical tests commonly employed in the management of PBC can be considered as surrogate markers of LPN. Taken together with our previous results, these findings suggest that liver biopsy may be necessary to screen UDCA-treated patients who might require additional therapies. [source]

Chondroitin sulfate increases hyaluronan production by human synoviocytes through differential regulation of hyaluronan synthases: Role of p38 and Akt

ARTHRITIS & RHEUMATISM, Issue 3 2009
Maha David-Raoudi
Objective To uncover the mechanism by which chondroitin sulfate (CS) enhances hyaluronan (HA) production by human osteoarthritic (OA) fibroblast-like synoviocytes (FLS). Methods The production of HA was investigated by exposing human OA FLS to CS in the presence or absence of interleukin-1, (IL-1,). HA levels were determined by enzyme-linked immunosorbent assay, and levels of messenger RNA (mRNA) for HA synthase 1 (HAS-1), HAS-2, and HAS-3 were determined by real-time polymerase chain reaction analysis. The effect of CS and IL-1, on signaling pathways was assessed by Western blotting. Specific inhibitors were used to determine their effects on both HA production and HAS expression. The molecular size of HA was analyzed by high-pressure liquid chromatography. Results CS increased HA production by FLS through up-regulation of the expression of HAS1 and HAS2. This was associated with activation of ERK-1/2, p38, and Akt, although to a lesser extent. Both p38 and Akt were involved in CS-induced HA accumulation. IL-1, increased HA production and levels of mRNA for HAS1, HAS2, and HAS3. CS enhanced the IL-1,,induced level of HAS2 mRNA and reduced the level of HAS3 mRNA. IL-1,,induced activation of p38 and JNK was slightly decreased by CS, whereas that of ERK-1/2 and Akt was enhanced. More high molecular weight HA was found in CS plus IL-1,,treated FLS than in FLS treated with IL-1, alone. Conclusion CS stimulates the synthesis of high molecular weight HA in OA FLS through up-regulation of HAS1 and HAS2. It reduces the IL-1,,enhanced transcription of HAS3 and increases the production of HA of large molecular sizes. These effects may be beneficial for maintaining viscosity and antiinflammatory properties in the joint. [source]