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Moderate Staining (moderate + staining)
Selected AbstractsCell type-dependent expression of HCN1 in the main olfactory bulbEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003Noémi B. Holderith Abstract In many brain regions, hyperpolarization-activated cationic currents (Ih) are involved in the generation of rhythmic activities, but the role of Ih in olfactory oscillations remains unclear. Knowledge of the cellular and subcellular distributions of hyperpolarization-activated and cyclic nucleotide-gated channel (HCN) subunits is necessary for understanding the role of Ih in olfactory network activities. Using light microscopic immunocytochemistry, we demonstrate strong HCN1 labelling of the glomerular layer and moderate staining of granule cell, internal and external plexiform layers of the rat main olfactory bulb. In the glomerular layer, among many unlabelled neurons, two distinct subpopulations of juxtaglomerular cells are labelled. Approximately 10% of the juxtaglomerular cells strongly express HCN1. These small diameter cells are immunoreactive for GABA and comprise a subpopulation of periglomerular cells. An additional subset of juxtaglomerular cells (, 1%) expresses low levels of HCN1. They are large in diameter, GABA immunonegative but immunopositive for vesicular glutamate transporter 2, characterizing them as external tufted cells. Quantitative immunogold localization revealed that the somatic plasma membranes of periglomerular cells contain approximately four times more HCN1 labelling than those of external tufted cells. Unlike in cortical pyramidal cells, immunogold density for HCN1 does not significantly differ in somatic and dendritic plasma membranes of external tufted cells, indicating that post-synaptic potentials arriving at proximal and distal dendrites are modulated by the same density of Ih. Our results demonstrate a cell type-dependent expression of HCN1 in the olfactory bulb and predict a differential contribution of distinct juxtaglomerular cell types to network oscillations. [source] Elevated expression of bisecting N -acetylglucosaminyltransferase-III gene in a human fetal hepatocyte cell line by hepatitis B virusJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2004JAE-KYOUNG SHIM Abstract Background and Aim:, UDP-N-acetylglucosamine: ,-D-mannoside ,-1,4 N-acetylglucosaminyltransferase III (GnT-III) is a key enzyme in N-glycan biosytnesis. Human GnT-III enzyme activity was found to be elevated in the serum of patients with hepatomas and liver cirrhosis and in hepatocellular carcinoma tissues. Therefore, to understand the relationship between the elevation in GnT-III activity and hepatitis B viral (HBV) hepartocarcinogenesis, we investigated GnT-III gene expression in the HBV-infected cells. Methods:, A cell line, HFH-T1, producing HBV was produced by natural infection of human fetal hepatocytes. A 170-bp band corresponding to the pre-S1 region of HBV was detected in the culture medium by polymerase chain reaction. Virions were also isolated from the culture medium by sucrose density gradient centrifugation. The synthesis of both ,-fetoprotein and albumin as an indicator that these cells were functional hepatocytes and the extent of differentiation was examined. Polymerase chain reaction and Western blot analysis using a monoclonal antibody, GT273, which was prepared using human aglycosyl recombinant GnT-III were used for HBV DNA and GnT-III detection. Results:, Two types of HBV-related particles were secreted into the culture medium; one was a Dane particle (40 nm in size) containing HBV DNA and the other was a subviral hepatitis B surface antigen particle (20 nm in size) that did not contain the viral genome. The secretion from the cell line was diminished by the number of passages and, thus, this cell was renamed as HFH-T2. A decreased level of the HBV was secreted from the cells after a rest period. HFH-T2 cells showed a weak staining for ,-fetoprotein and a moderate staining for albumin in the cytoplasm around the nucleus. High levels of a 0.7 kb DNA fragment originating from GnT-III DNA were detected in HFH-T2 cells. Western blot analysis using a monoclonal antibody, GT273, whixh was prepared using human aglycosyl recombinant GnT-III showed a single band, corresponding to Mr 63 kDa, whereas aglycosyl GnT-III showed a band at Mr 53 kDa, with a molecular weight difference of about 10 kDa. This indicates that HFH-T2 cells express glycosylated GnT-III. GnT-III activities were 347.2 ± 53.6 pmol/mg of protein/h in HFH-T2, 276 ± 26.3 in Hep3B, 252.5 ± 23.3 in HepG2 and 30.7 ± 3.4 in NIH-3T3. GnT-III activity was higher in HFH-T2 cells than in the hepatoma cell lines, Hep3B and HepG2. Conclusion:, A human fetal hepatocyte cell line was transformed by infection with HBV and the cell line expressed high levels of GnT-III as the levels of secretion of HBV decreased. The decrease in HBV secretion from HFH-T2 cells could be due to a high level of expression of GnT-III. Such a cell line could be used to investigate relationships between HBV infection and glycosyltransferase gene expression. Furthermore, this cell line will be useful in future studies on the effect of the expression of GnT-III on other glycosyltransferase. [source] Post-transplant recurrent hepatitis C: immunohistochemical detection of hepatitis C virus core antigen and possible pathogenic implicationsLIVER INTERNATIONAL, Issue 6 2008Mário G. Pessôa Abstract Introduction: The mechanisms by which severe cholestatic hepatitis develops after liver transplantation are not fully understood. Reports on immunohistochemical distribution of hepatitis C virus (HCV) antigens are still scarce, but recently, HCV immunostaining was suggested for early diagnosis of cholestatic forms of recurrent hepatitis C in liver grafts. After purification, Rb246 pab anticore (aa1-68) yielded specific, granular cytoplasmic staining in hepatocytes. Signal amplification through the Envision-Alkaline Phosphatase System avoided endogenous biotin and peroxidase. Aims/Methods: Rb246 was applied to liver samples of explants of 12 transplant recipients, six with the most severe form of post-transplantation recurrence, severe cholestatic hepatitis (group 1) and six with mild recurrence (group 2). We also assessed immuno-reactivity at two time-points post-transplantation (median 4 and 22 months) in both groups. HCV-core Ag was semiquantified from 0 to 3+ in each time point. Serum HCV-RNA was also measured on the different time points by branched DNA. Results: In the early post-transplant time point, one patient had a mild staining (1+), two patients had a moderate staining (2+) and the other three had no staining in group 1, compared with five patients with no staining (0) and one patient with mild staining (1+) in group 2. Late post-transplant liver samples were available in nine patients, and two out of four samples in group 1 showed a mild staining, compared with no staining patients in five patients in group 2. Strikingly, on the explant samples, HCV immunostaining was strongly positive in group 1, and mildly positive in group 2. Two out of five samples showed 3+ staining, and three samples showed 2+ staining in group 1; two out of five samples showed no staining, two samples showed 1+ staining and one sample showed 2+ staining in group 2. Serum HCV-RNA was significantly higher in group 1, on both time-points post-transplantation. HCV-core Ag was not directly associated with serum HCV-RNA on the different time points. Conclusion: These preliminary results suggest that strong HCV immunostaining in the explant is predictive of more severe disease recurrence. [source] Immunohistochemical analysis of CYP2A13 in various types of human lung cancersCANCER SCIENCE, Issue 4 2010Tatsuki Fukami Human CYP2A13, which is expressed in the respiratory tract, is the most efficient enzyme for the metabolic activation of tobacco-specific nitrosamines such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The relevance of CYP2A13 in carcinogenicity and toxicity in the respiratory tract has been suggested, but the expression of CYP2A13 protein in lung cancer tissues remains to be determined. We first prepared a mouse monoclonal antibody against human CYP2A13. The antibody showed no cross reactivity with the other CYP isoforms including CYP2A6. Using the specific antibody, we performed immunohistochemical analysis for human lung carcinomas. In adenocarcinomas (n = 15), all specimens were positive for the staining and five samples showed strong staining. In squamous cell carcinomas (n = 15) and large cell carcinomas (n = 15), each 14 samples were positive for the staining and two and three samples showed strong staining, respectively. In small cell carcinoma samples (n = 15), eight samples were negative for the staining and five samples showed weak or moderate staining. In conclusion, we first found that the expression of CYP2A13 was markedly increased in non-small cell lung carcinomas. The high expression might be associated with the tumor development and progression in non-small cell lung carcinomas. (Cancer Sci 2010; 101: 1024,1028) [source] Differential expression of two new members of the p53 family, p63 and p73, in extramammary Paget's diseaseCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 5 2008S. Chen Summary Background., The proteins p53, p63 and p73 are known to be overexpressed and to play important roles in the pathogenesis of many tumours, but the expression of p63 and p73 has not previously been investigated in extramammary Paget's disease (EMPD). Aim., To investigate the potential contribution of p53, p63 and p73 in the pathogenesis of EMPD. Methods., In total, 35 paraffin wax-embedded tissue samples from patients with EMPD were examined using immunohistochemical staining for p53, p63 and p73. Results., All of the 35 EMPD specimens, including all 6 invasive EMPD and 2 metastatic lymph-node specimens, showed nuclear overexpression of both p53 and p73. The expression levels (percentage of positive cells) of p53 and p73 (90.66 ± 12.53% and 80.20 ± 13.07%) in EMPD were significantly higher than those of normal skin. There was a significant correlation between the expression levels of p53 and p73 in EMPD. In 29 of 35 EMPD specimens, there was no nuclear expression of p63, and weak or moderate staining was found in only 6 specimens. The expression level of p63 in EMPD was significantly less than that in normal skin. Conclusions., Our study shows that the concordant overexpression of p53 and p73 and the decreased expression of p63 may play a pivotal role in the pathogenesis of EMPD. The decreased expression of p63 may play a more important role in the pathogenesis of EMPD than the overexpression of p53 and p73. [source] | ||||||||||