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1.

Background  

Cystic Fibrosis is a pleiotropic disease in humans with primary morbidity and mortality associated with a lung disease phenotype. However, knockout in the mouse of cftr, the gene whose mutant alleles are responsible for cystic fibrosis, has previously failed to produce a readily, quantifiable lung phenotype.  相似文献   
2.
OBJECTIVE: To determine whether tumor marker pi glutathione transferase (GST-pi) is expressed in hepatocellular carcinoma (HCC) and other chronic liver diseases and to compare its expression with that of alpha-fetoprotein (AFP). STUDY DESIGN: Samples used were formalin-fixed, paraffin-embedded liver tissues: normal (n = 3), chronic hepatitis B (n = 15), cirrhosis (n = 15) and HCC (n = 30). The expression of AFP and GST-pi was detected by using immunohistochemistry with the peroxidase-antiperoxidase method. AFP immunoreactivity was based on the cytoplasm of the hepatocytes, while GST-pi immunoreactivity was based on the nuclei of hepatocytes. RESULTS: In normal liver tissues, AFP was not expressed. However, there was strong staining of GST-pi in bile duct epithelium cells and weak staining in hepatocytes. Our results showed higher AFP immunoreactivity in cases of HCC (36.7%) as compared to cirrhosis (6.7%) and hepatitis B (0%), whereas GST-pi immunoreactivity was lower in cases of HCC (53.3%) as compared to cases of cirrhosis (100.0%) and hepatitis B (93.3%). Percent sensitivity of AFP determination for HCC was 36.7% as compared to 53.3% for GST-pi, thus making GST-pi a more sensitive marker for detection of HCC. This study showed a significant relationship between the intensity and percentage of cells stained in hepatitis B, cirrhosis and HCC for GST-pi immunoreactivity (P < .001, .001 and .05, respectively) but not for AFP (P > .05). Statistical analysis showed that there was no significant relationship between expression of AFP and GST-pi in cirrhosis and HCC cases. Hepatitis B virus infection in HCC cases showed a positive rate of 46.7%, with AFP staining positively in 42.9% of tissues and GST-pi staining positively in 57.1% of tissues. CONCLUSION: AFP is a diagnostic but rather insensitive tissue marker for HCC. However, the absence of AFP in benign chronic liver disease makes this marker useful in differentiating between HCC and other chronic liver diseases, whereas GST-pi can be used as a diagnostic marker for HCC as well as in detecting other chronic liver diseases.  相似文献   
3.
4.

Background

The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.

Results

Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.

Conclusions

Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.
  相似文献   
5.

Background

We developed a new version of the open source software package Peptrix that can yet compare large numbers of Orbitrap? LC-MS data. The peptide profiling results for Peptrix on MS1 spectra were compared with those obtained from a small selection of open source and commercial software packages: msInspect, Sieve? and Progenesis?. The properties compared in these packages were speed, total number of detected masses, redundancy of masses, reproducibility in numbers and CV of intensity, overlap of masses, and differences in peptide peak intensities. Reproducibility measurements were taken for the different MS1 software applications by measuring in triplicate a complex peptide mixture of immunoglobulin on the Orbitrap? mass spectrometer. Values of peptide masses detected from the high intensity peaks of the MS1 spectra by peptide profiling were verified with values of the MS2 fragmented and sequenced masses that resulted in protein identifications with a significant score.

Findings

Peptrix finds about the same number of peptide features as the other packages, but peptide masses are in some cases approximately 5 to 10 times less redundant present in the peptide profile matrix. The Peptrix profile matrix displays the largest overlap when comparing the number of masses in a pair between two software applications. The overlap of peptide masses between software packages of low intensity peaks in the spectra is remarkably low with about 50% of the detected masses in the individual packages. Peptrix does not differ from the other packages in detecting 96% of the masses that relate to highly abundant sequenced proteins. MS1 peak intensities vary between the applications in a non linear way as they are not processed using the same method.

Conclusions

Peptrix is capable of peptide profiling using Orbitrap? files and finding differential expressed peptides in body fluid and tissue samples. The number of peptide masses detected in Orbitrap? files can be increased by using more MS1 peptide profiling applications, including Peptrix, since it appears from the comparison of Peptrix with the other applications that all software packages have likely a high false negative rate of low intensity peptide peaks (missing peptides).  相似文献   
6.
cDNAs encoding TCR alpha- and beta-chains specific for HLA-A2-restricted cancer-testis Ag NY-ESO-1 were cloned using a 5'RACE method from RNA isolated from a CTL generated by in vitro stimulation of PBMC with modified NY-ESO-1-specific peptide (p157-165, 9V). Functionality of the cloned TCR was confirmed by RNA electroporation of primary PBL. cDNA for these alpha- and beta-chains were used to construct a murine stem cell virus-based retroviral vector, and high titer packaging cell lines were generated. Gene transfer efficiency in primary T lymphocytes of up to 60% was obtained without selection using a method of precoating retroviral vectors onto culture plates. Both CD4(+) and CD8(+) T cells could be transduced at the same efficiency. High avidity Ag recognition was demonstrated by coculture of transduced lymphocytes with target cells pulsed with low levels of peptide (<20 pM). TCR-transduced CD4 T cells, when cocultured with NY-ESO-1 peptide pulsed T2 cells, could produce IFN-gamma, GM-CSF, IL-4, and IL-10, suggesting CD8-independent, HLA-A2-restricted TCR activation. The transduced lymphocytes could efficiently recognize and kill HLA-A2- and NY-ESO-1-positive melanoma cell lines in a 4-h (51)Cr release assay. Finally, transduced T cells could efficiently recognize NY-ESO-1-positive nonmelanoma tumor cell lines. These results strongly support the idea that redirection of normal T cell specificity by TCR gene transfer can have potential applications in tumor adoptive immunotherapy.  相似文献   
7.

Background

Canine hemangiosarcoma (HSA) is a malignant tumor with poor long-term prognosis due to development of metastasis despite aggressive treatment. The phosphatidyl-inositol-3 kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway is involved in its endothelial pathologies; however, it remains unknown how this pathway plays a role in canine HSA. Here, we characterized new canine HSA cell lines derived from nude mice-xenografted canine HSAs and investigated the deregulation of the signaling pathways in these cell lines.

Results

Seven canine HSA cell lines were established from 3 xenograft canine HSAs and showed characteristics of endothelial cells (ECs), that is, uptake of acetylated low-density lipoprotein and expression of canine-specific CD31 mRNA. They showed varied morphologies and mRNA expression levels for VEGF-A, bFGF, HGF, IGF-I, EGF, PDGF-B, and their receptors. Cell proliferation was stimulated by these growth factors and fetal bovine serum (FBS) in 1 cell line and by FBS alone in 3 cell lines. However, cell proliferation was not stimulated by growth factors and FBS in the remaining 3 cell lines. Phosphorylated p44/42 Erk1/2 was increased by FBS stimulation in 4 cell lines. In contrast, phosphorylation of Akt at Ser473, mTOR complex 1 (mTORC1) at Ser2448, and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) at Ser65 was high in serum-starved condition and not altered by FBS stimulation in 6 cell lines, despite increased phosphorylation of these residues in normal canine ECs. This suggested that the mTORC2/Akt/4E-BP1 pathway was constitutively activated in these 6 canine HSA cell lines. After cell inoculation into nude mice, canine HSA tumors were formed from 4 cell lines and showed Akt and 4E-BP1 phosphorylation identical to the parental cell lines.

Conclusions

Our findings suggest that the present cell lines may be useful tools for investigating the role of the mTORC2/Akt/4E-BP1 pathway in canine HSA formation both in vivo and in vitro.  相似文献   
8.
We have performed a detailed analysis of the recognition of melanoma Ags by the tumor-infiltrating lymphocytes (TIL) 1790, isolated from a patient who experienced a dramatic tumor regression following immunization with peptides from the gp100, MART-1, and tyrosinase Ags. This TIL was found to recognize HLA-A2-restricted CTL epitopes in tyrosinase-related protein (TRP)-2 (clone MR7) and NY-ESO-1 (clone M8). These epitopes were the same as the previously identified nonapeptide TRP-2: 180-188, and the overlapping NY-ESO-1 peptides, obtained by using lymphocytes from in vitro stimulation. We also cloned a previously unknown TRP-2 mRNA isoform (TRP-2-6b) that contained two novel exons alternatively spliced from the sixth intron between exons 6 and 7 of TRP-2 mRNA. The isoform encoded an HLA-A2-restricted antigenic epitope recognized by TIL clone MB4. An immunologic analysis of the patient's PBMC obtained before treatment showed the presence of high reactivity against NY-ESO-1 and both TRP-2 Ags, but not the Ags used for immunization. Because immune response against these Ags was less pronounced, it is possible that NY-ESO-1, TRP-2, and TRP-2-6b may be of importance in the generation of CTL-mediated tumor destruction and may have played a role in the dramatic tumor regression seen in this patient.  相似文献   
9.
The number of grains per panicle is an important yield-related trait in cereals which depends in part on panicle branching complexity. One component of this complexity is the number of secondary branches per panicle. Previously, a GWAS site associated with secondary branch and spikelet numbers per panicle in rice was identified. Here we combined gene capture, bi-parental genetic population analysis, expression profiling and transgenic approaches in order to investigate the functional significance of a cluster of 6 ANK and ANK-TPR genes within the QTL. Four of the ANK and ANK-TPR genes present a differential expression associated with panicle secondary branch number in contrasted accessions. These differential expression patterns correlate in the different alleles of these genes with specific deletions of potential cis-regulatory sequences in their promoters. Two of these genes were confirmed through functional analysis as playing a role in the control of panicle architecture. Our findings indicate that secondary branching diversity in the rice panicle is governed in part by differentially expressed genes within this cluster encoding ANK and ANK-TPR domain proteins that may act as positive or negative regulators of panicle meristem’s identity transition from indeterminate to determinate state.  相似文献   
10.
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