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Hiroyuki Yamamoto

Publications and source records attributed to Hiroyuki Yamamoto.

At least 37 records · Page 2Linked to original sources
PubMed2006

Sulfurivirga caldicuralii gen. nov., sp. nov., a novel microaerobic, thermophilic, thiosulfate-oxidizing chemolithoautotroph, isolated from a shallow marine hydrothermal system occurring in a coral reef, Japan.

Novel thermophilic bacteria, designated strains VW1 and MM1(T), were isolated from hydrothermal fluid and microbial mat samples, respectively, collected from a shallow marine hydrothermal system (water depth 22 m) occurring in coral reefs off Taketomi Island, Okinawa, Japan. Cells of the two novel strains were motile rods with a single polar flagellum in the exponential growth phase. In a medium that included elemental sulfur, cells of the two strains became non-motile with oval to spherical cell shapes. For both strains, growth occurred at between 30 and 60 degrees C (optimum temperature of 50-55 degrees C; 60-80 min doubling time) and between pH 5.5 and 7.1 (optimum pH 6.0). The isolates were microaerobic chemolithoautotrophs capable of using thiosulfate or tetrathionate as the sole energy source, O(2) as the sole electron acceptor and CO(2) as the sole carbon source. Organic substrates, such as yeast extract and tryptone, inhibited growth of both strains. The G+C contents of genomic DNA were 51.3 and 49.5 mol% for strains VW1 and MM1(T), respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains were closely related to each other (99.9 % sequence similarity) and were distantly related to other previously described genera within the Gammaproteobacteria. The novel isolates could also be differentiated from other gammaproteobacterial genera on the basis of their physiological properties. It is suggested that the novel isolates represent the type species of a new genus, for which the name Sulfurivirga caldicuralii gen. nov., sp. nov. (type strain MM1(T)=JCM 13439(T)=DSM 17737(T)) is proposed.

Animals↗
PubMed2006

Involvement of multiple epitope-specific cytotoxic T-lymphocyte responses in vaccine-based control of simian immunodeficiency virus replication in rhesus macaques.

Cytotoxic T-lymphocyte (CTL) responses are crucial for the control of immunodeficiency virus replication. Possible involvement of a dominant single epitope-specific CTL in control of viral replication has recently been indicated in preclinical AIDS vaccine trials, but it has remained unclear if multiple epitope-specific CTLs can be involved in the vaccine-based control. Here, by following up five rhesus macaques that showed vaccine-based control of primary replication of a simian immunodeficiency virus, SIVmac239, we present evidence indicating involvement of multiple epitope-specific CTL responses in this control. Three macaques maintained control for more than 2 years without additional mutations in the provirus. However, in the other two that shared a major histocompatibility complex haplotype, viral mutations were accumulated in a similar order, leading to viral evasion from three epitope-specific CTL responses with viral fitness costs. Accumulation of these multiple escape mutations resulted in the reappearance of plasma viremia around week 60 after challenge. Our results implicate multiple epitope-specific CTL responses in control of immunodeficiency virus replication and furthermore suggest that sequential accumulation of multiple CTL escape mutations, if allowed, can result in viral evasion from this control.

Amino Acid Substitution↗
PubMed2006

Role of matrix metalloproteinase-7 (matrilysin) in human cancer invasion, apoptosis, growth, and angiogenesis.

Matrix metalloproteinase (MMP)-7, also known as matrilysin, is a "minimal domain MMP" that exhibits proteolytic activity against components of the extracellular matrix (ECM). Matrilysin is frequently overexpressed in human cancer tissues and is associated with cancer progression. Tumorigenesis is a multistep process involving cell growth, invasion, metastasis, and angiogenesis. Matrilysin has been shown to play important roles not only in degradation of ECM proteins, but also in the regulation of several biochemical processes such as activation, degradation, and shedding of non-ECM proteins. This minire-view provides a summary of the current literature on the roles of matrilysin in tumorigenesis with a focus on the roles of modifications of non-ECM proteins by matrilysin and other related MMPs in tumorigenesis. Proteolysis of insulin-like growth factor binding protein by matrilysin results in increased bioavailability of insulin-like growth factors and enhanced cellular proliferation. Matrilysin has also been implicated in the ectodomain shedding of several cell surface molecules. Heparin-binding epidermal growth factor precursor (proHB-EGF) is cleaved by matrilysin into mature HB-EGF, which promotes cellular proliferation. Membrane-bound Fas ligand (FasL) is cleaved into soluble FasL, which increases apoptosis of cells adjacent to tumor cells. E-cadherin is converted to soluble E-cadherin to promote invasion. Tumor necrosis factor (TNF)-alpha precursor is cleaved to release soluble TNF-alpha to increase apoptosis. We propose that these matrilysin-mediated pathways provide the necessary and logical mechanisms to promote cancer progression.

Animals↗
PubMed2006

Pharmacological differences between Liu-Jun-Zi-Tang, a traditional Chinese herbal medicine, and domperidone on isolated guinea-pig ileum.

The different characteristics of Liu-Jun-Zi-Tang, a spray-dried powdered extract from 8 Chinese herbs, and domperidone, a D2 antagonist, both of which are used clinically for the treatment of gastritis, were validated in isolated guinea pig ileal longitudinal muscle. Liu-Jun-Zi-Tang at 0.05 mg/ml did not affect the twitch response by electrical field stimulation, but it concentration-dependently inhibited the twitch response at concentrations of 0.1 and 1.0 mg/ml, and maximum inhibition occurred 5 min after application of Liu-Jun-Zi-Tang. In the presence of Liu-Jun-Zi-Tang, the concentration-response curve for ACh-contraction showed inhibition in a non-competitive manner, which is the same as domperidone. In the presence of Liu-Jun-Zi-Tang (1.0 mg/ml), ACh (10(-7) M)-, histamine (5x10(-7) M)- and barium chloride (10(-4) M)-induced basal contractions were inhibited by 24, 19 and 54 %, respectively. On the other hand, in the presence of domperidone (2x10(-5) M), ACh- and barium chloride-induced basal contractions were inhibited by 28 and 63%, respectively, similar to that in the presence of Liu-Jun-Zi-Tang. However, the inhibition of histamine-induced contraction in the presence of domperidone was significantly increased (81%) compared with that in the presence of Liu-Jun-Zi-Tang. These findings suggest that Liu-Jun-Zi-Tang has milder effects on histamine-induced disorders than domperidone. In other words, domperidone has a more potent effect on histamine-induced disorders.

Acetylcholine↗
PubMed2006

[A case in which the subject was affected by Listeia meningoencephalitis during administration of infliximab for steroid-dependent adult onset Still's disease].

The subject was a 22-year-old woman who developed high fever and arthralgias and eruptions in the extremities around June 2005. She sought medical advice at a nearby dermatology clinic, where hepatic dysfunction was noted on blood testing. The patient was thus hospitalized the next day. Although CRP levels were significantly high, no sign of infection was observed and bone marrow cell differentiation was normal. Adult onset Still's disease was diagnosed based on the observation of persistent high fever >39 degrees C, eruptions, increased leukocytes, pharyngeal pain, splenomegaly, hepatic dysfunction, negative autoantibody results from blood testing, and high serum ferritin levels. Administration of prednisolone 30 mg/day was initiated, but proved ineffective. Steroid pulse therapy was conducted, and the subject was transferred to our medical facility for continued treatment. Attempts were made to control the disease using combined steroid and cyclosporine administration; but exacerbation of high serum ferritin levels and hepatic dysfunctions were observed, so a second course of steroid pulse therapy was conducted. Symptoms improved temporarily, but steroid levels were difficult to reduce. Cyclosporine was therefore replaced by methotrexate, and administration of infliximab was initiated. In the course of treatment, administration of a sulfamethoxazole/trimethoprim combination was initiated, but was discontinued due to suspicion of drug-induced hepatic injury. A second administration of infliximab was conducted in late August, and rapid improvements in clinical symptoms and abnormal test values was observed. However, high fever and headache developed suddenly in early September. Based on the results of spinal fluid testing, blood and spinal fluid cultures and MRI of the head, Listeria meningoencephalitis was diagnosed. Diplopia and impaired consciousness occurred during the disease course, and formation of a brain abscess was observed on imaging. However, symptoms were controlled by long-term combination administration of ampicillin and gentamicin. Administration of infliximab was discontinued for treatment of adult onset Still's disease, and steroid levels were reduced following double-membrane filtration plasma exchange. On follow-up, no relapse of symptoms or abnormalities in blood test values were observed, so the subject was discharged from our medical facility in December 2005. In treatment for rheumatic diseases, a dramatic improvement in treatment results for pathologies displaying tolerance against conventional treatments has been acquired with the development of biological drugs. However, opportunistic infections represent a serious problem, and appropriate preventative measures are required. The present report describes a case in which the subject was affected by Listeria meningoencephalitis during administration of infliximab for steroid-dependent adult Still's disease. Since listeriosis is one of the complications, along with tuberculosis, that warrants precautionary measures, this case is reported and discussed.

Adult↗
PubMed2006

Activation of the ribosomal protein L13 gene in human gastrointestinal cancer.

Although ribosomal proteins are major components of ribosomes, recent data have shown them to have extraribosomal functions apart from ribosome and protein biosynthesis. In our earlier study, we showed that ribosomal protein L13 mRNA was up-regulated in response to DNA damage in hamster cells. We report here that L13 expression is up-regulated in human gastrointestinal cancers. We also examined the biological role of L13 on human cancer cells. Knocking down L13 expression using small interfering RNA (siRNA) resulted in drastic attenuation of cancer cell growth with significant G1 and G2/M arrest of the cell cycle. Moreover, L13 siRNA significantly enhanced the cellular sensitivity to certain DNA damaging agents and, concordantly, L13-overexpressing cells demonstrated greater chemoresistance compared to parent cells, suggesting an inverse correlation between L13 expression and chemosensitivity. By using semiquantitative RT-PCR, we analyzed expression of L13 in freshly resected cancer tissue of the stomach, colorectum and liver. Up-regulation of L13 mRNA expression was observed in 10 (28%) of 36 gastric, 19 (41%) of 46 colorectal and 5 (20%) of 25 liver cancer tissue samples compared to adjacent normal tissue samples. We also found that increased expression of the L13 gene correlated with clinical staging in gastric cancers. The results of this study suggest that L13 plays an essential role in the progression of some gastrointestinal malignancies.

Animals↗
PubMed2005

Frequent epigenetic inactivation of Wnt inhibitory factor-1 in human gastrointestinal cancers.

Aberrant activation and upregulation of the Wnt pathway is a key feature of many cancers. Wnt antagonists have recently attracted wide attention. Wnt inhibitory factor-1 (WIF-1) is a secreted antagonist that can bind to Wnt proteins directly and inhibit Wnt signaling pathway. It has been reported that WIF-1 expression is down regulated in several solid tumors and that WIF-1 is silenced by promoter hypermethylation in lung and colorectal cancer. By using RT-PCR, bisulfite sequence analysis, and methylation-specific PCR, we analysed expression and methylation of WIF-1 in cancer cell lines and freshly resected cancer tissues of the esophagus, stomach, colorectum, and pancreas. Downregulation of WIF-1 mRNA expression was observed in 61 (91.0%) of 67 cancer cell lines, 16 (80.0%) of 20 esophageal, 23 (74.2%) of 31 gastric, 41 (82.0%) of 50 colorectal, and six (75.0%) of eight pancreatic cancer tissues. Downregulation of WIF-1 expression was also observed at protein level. No significant association between WIF-1 downregulation and clinicopathological characteristics was found, suggesting that downregulation of WIF-1 expression is an early event in carcinogenesis of these cancers. Indeed, downregulation of WIF-1 expression was observed in 32 (72.7%) of 44 colorectal adenoma tissues and 18 (78.2%) of 23 early mucosal or submucosal colorectal carcinoma tissues. CpG island hypermethylation in the WIF-1 promoter region correlated with downregulation of WIF-1 expression in cancer cell lines and tissues. Treatment with demethylating agent, 5-aza-2'-deoxycytidine (5-aza-dC), restored WIF-1 expression in cancer cell lines. A combined treatment of 5-aza-dC and a histone deacetylase inhibitor, trichostatinA, restored WIF-1 expression synergistically, indicating the role of cytosine methylation and histone deacetylation in the silencing of the WIF-1 gene. Transfection of the WIF-1 gene construct into TE-1 esophageal cancer cell lines or SW48 colon cancer cell lines lacking WIF-1 expression resulted in a significant inhibition on colony formation, cell proliferation, anchorage-independent growth in soft agar. TOPflash assay showed WIF-1 inhibits Wnt canonical signaling in these cell lines. These results suggest tumor suppressive function of WIF-1, due to its ability to inhibit Wnt signaling. Our results suggest that WIF-1 silencing due to promoter hypermethylation is an important mechanism underlying aberrant activation of the Wnt signaling pathway in carcinogenesis of the digestive organs. Modulation of the Wnt pathway, through reversal of WIF-1 silencing by demethylating agents, is a potential target for treatment and/or prevention of gastrointestinal cancers.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Concomitant RASSF1A hypermethylation and KRAS/BRAF mutations occur preferentially in MSI sporadic colorectal cancer.

Methylation-associated inactivation of RASSF1A has frequently been observed in several human malignancies including sporadic colorectal and gastric cancer. However, nothing is known about the RASSF1A methylation status in the setting of MMR-deficient gastrointestinal tumours. In this study, we analysed systematically alterations in KRAS, BRAF and RASSF1A, in order to define the frequency and the pattern of these genetic/epigenetic alterations in three distinct subsets of MSI gastrointestinal tumours. Further, an association study was performed between RASSF1A methylation and the clinicopathological parameters in order to determine the profile of tumours harbouring this epigenetic event. A total of 56 MSI sporadic gastrointestinal tumours (31 colorectal and 25 gastric) and 20 MSI HNPCC analysed for KRAS/BRAF were analysed for RASSF1A promoter hypermethylation by MSP and DNA sequencing. No significant differences were found between the frequency of RASSF1A methylation in sporadic MSI colorectal and gastric carcinomas and HNPCC carcinomas (P=0.31). Methylation of RASSF1A was present in 16 of 31 (52%) sporadic MSI colorectal and 11 of 25 (44%) MSI gastric carcinomas, and in six of 20 (30%) HNPCC carcinomas. Nearly 36% of MSI sporadic colorectal carcinomas (CRCs) had RASSF1A methylation and activating mutations at KRAS and/or BRAF. In contrast, only 10 and 8% of HNPCC and sporadic gastric carcinomas, respectively, had concomitant KRAS mutations and RASSF1A methylation. The MSI sporadic gastric and CRCs with RASSF1A methylation were preferentially poorly differentiated (P=0.03, 0.05, respectively). We show that the profile of alterations RASSF1A, KRAS/BRAF is different among the three groups of MSI gastrointestinal tumours. Further, we demonstrate that MSI sporadic CRCs accumulated significantly more epigenetic/genetic alterations in RASSF1A, KRAS/BRAF than MSI sporadic gastric or HNPCC carcinomas (P=0.016). These results are likely to have therapeutic implications in the near future, due to the possibilities of using specific kinase inhibitors alone or in association with demethylating agents in MSI tumour types harbouring KRAS or BRAF mutations and RASSF1A methylation.

Carcinoma↗
PubMed2005

Mechanisms of inactivation of the receptor tyrosine kinase EPHB2 in colorectal tumors.

The receptor tyrosine kinase EPHB2 has recently been shown to be a direct transcriptional target of TCF/beta-catenin. Premalignant lesions of the colon express high levels of EPHB2 but the expression of this kinase is reduced or lost in most colorectal carcinomas. In addition, inactivation of EPHB2 has been shown to accelerate tumorigenesis initiated by APC mutation in the colon and rectum. In this study, we investigated the molecular mechanisms responsible for the inactivation of EPHB2 in colorectal tumors. We show here the presence of mutations in repetitive sequences in exon 17 of EPHB2 in 6 of 29 adenomas with microsatellite instability (MSI), and 101 of 246 MSI carcinomas (21% and 41%, respectively). Moreover, we found EPHB2 promoter hypermethylation in 54 of the 101 colorectal tumors studied (53%). Importantly, EPHB2 expression was restored after treatment of EPHB2-methylated colon cancer cells with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine. In conclusion, in this study, we elucidate the molecular mechanisms of inactivation of EPHB2 and show for the first time the high incidence of frameshift mutations in MSI colorectal tumors and aberrant methylation of the regulatory sequences of this important tumor suppressor gene.

Adenoma↗
PubMed2005

The association of DNA-dependent protein kinase activity with chromosomal instability and risk of cancer.

The DNA double-strand breaks (DSBs) repair pathway has been implicated in maintaining genomic integrity via suppression of chromosomal rearrangements. DNA-dependent protein kinase (DNA-PK) has an important role with DNA DSBs repair. In this study, 93 of untreated cancer patients and 41 of cancer-free healthy volunteers were enrolled. Peripheral blood was collected, separated and centrifuged; DNA-PK activity was measured by DNA-pull-down assay. The expressions of DNA-PKcs, Ku70 and Ku86 were examined by RT-PCR assay and western blotting. Chromosomal aberrations were examined by cytogenetic methods. DNA-PK activities of peripheral blood lymphocytes (PBL) in patients with uterine cervix or breast cancer were significantly lower than those in normal volunteers. Age and smoking had no association with DNA-PK activity, whereas DNA-PK activity and the expression of Ku70, Ku86 and DNA-PKcs in RT-PCR were interrelated. A similar tendency was seen in western blot assay but less clear than in RT-PCR. Therefore, the association between DNA-PK activity and expression of DNA-PK in protein level could not be concluded. The frequency of chromosome aberration, such as dicentric chromosomes and excess fragment increased as the DNA-PK activity decreased. In conclusion, DNA-PK activity is associated with chromosomal instability. DNA-PK activity in PBL is associated with risk of breast and uterine cervix cancer. DNA-PK activity in PBL can be used to select individuals for whom an examination should be performed because of their increased susceptibility to breast and uterine cervix cancer.

Adult↗
PubMed2005

Microbial community in a geothermal aquifer associated with the subsurface of the Great Artesian Basin, Australia.

To investigate the biomass and phylogenetic diversity of the microbial community inhabiting the deep aquifer of the Great Artesian Basin (GAB), geothermal groundwater gushing out from the aquifer was sampled and analyzed. Microbial cells in the groundwater were stained with acridine orange and directly counted by epifluorescence microscopy. Microbial cells were present at a density of 10(8)-10(9) cells per liter of groundwater. Archaeal and bacterial small-subunit rRNA genes (rDNAs) were amplified by PCR with Archaea- and Bacteria-specific primer sets, and clone libraries were constructed separately. A total of 59 clones were analyzed in archaeal and bacterial 16S rDNA libraries, respectively. The archaeal 16S rDNA clones were divided into nine operated taxonomic units (OTUs) by restriction fragment length polymorphism. These OTUs were closely related to the methanogenic genera Methanospirillum and Methanosaeta, the heterotrophic genus Thermoplasma, or miscellaneous crenarchaeota group. More than one-half of the archaeal clones (59% of total 59 clones) were placed beside phylogenetic clusters of methanogens. The majority of the methanogen-related clones (83%) was closely related to a group of hydrogenotrophic methanogens (genus Methanospirillum). The bacterial OTUs branched into seven phylogenetic clusters related to hydrogen-oxidizing thermophiles in the genera Hydrogenobacter and Hydrogenophilus, a sulfate-reducing thermophile in the genus Thermodesulfovibrio, chemoheterotropic bacteria in the genera Thermus and Aquaspirillum, or the candidate division OP10. Clones closely related to the thermophilic hydrogen-oxidizers in the genera Hydrogenobacter and Hydrogenophilus were dominant in the bacterial clone library (37% of a total of 59 clones). The dominancy of hydrogen-users strongly suggested that H(2) plays an important role as a primary substrate in the microbial ecosystem of this deep geothermal aquifer.

Archaea↗
PubMed2005

BRAF-V600E is not involved in the colorectal tumorigenesis of HNPCC in patients with functional MLH1 and MSH2 genes.

Recently, it was shown that the oncogenic activation of BRAF, a member of the RAS/RAF family of kinases, by the V600E mutation is characteristic for sporadic colon tumors with microsatellite instability. Further, it was shown to associate with the silencing of the mismatch repair (MMR) gene MLH1 by hypermethylation. Moreover, BRAF mutations proved to be absent in tumors from hereditary nonpolyposis colorectal cancer syndrome (HNPCC) families with germline mutations in the MMR genes MLH1 and MSH2. These data suggest that the oncogenic activation of BRAF is involved only in sporadic colorectal tumorigenesis. In order to further support this hypothesis, we have extended the analysis of the BRAF gene to a different subset of HNPCC families without germline mutations in MLH1 and MSH2. BRAF-V600E mutations were analysed by automatic sequencing in 38 tumors from HNPCC families with germline mutations in the MSH6 gene and also in HNPCC (suspected) families that do not have mutations in the MMR genes MLH1, MSH2 and MSH6. All patients belong to different families. No mutations were detected in 14 tumors from HNPCC patients with germline mutations in MSH6. Further, no mutations of BRAF were found in tumors from 23 MMR-negative families, from which 13 fulfilled the Amsterdam criteria (HNPCC) and 10 were suspected for HNPCC as they were positive for the Bethesda criteria. Overall, our data reinforce the concept that BRAF is not involved in the colorectal tumorigenesis of HNPCC. The detection of a positive BRAF-V600E mutation in a colorectal cancer suggests a sporadic origin of the disease and the absence of germline alterations of MLH1, MSH2 and also of MSH6. These findings have a potential impact in the genetic testing for HNPCC diagnostics and suggest a potential use of BRAF as exclusion criteria for HNPCC or as a molecular marker of sporadic cancer.

Amino Acid Substitution↗
PubMed2005

Alkaline phosphatase encapsulated in gellan-chitosan hybrid capsules.

Alkaline phosphatase (ALP) was encapsulated in gellan-chitosan polyion complex (PIC) capsules using a convenient procedure. The recovery of ALP was about 50% when the capsules were prepared by dropping a solution of ALP and gellan mixture (ALP/gellan) into a chitosan solution. When p-nitrophenyl phosphate (p-NPP) and 5-bromo-4-chloro-3-indolyl phosphate (BCIP) were incubated with ALP/gellan-chitosan capsules as substrates for ALP, the transparent colorless capsules changed to yellow and blue, respectively. The encapsulation of ALP into the PIC capsules was also confirmed by SDS-PAGE and immunoblot analyses. The ALP and polypeptides of more than 30 kDa remained without release even after incubation at 4 degrees C for 14 d. The biochemical properties of the encapsulated ALP activity were similar to those of the intact enzyme. When the solution containing p-NPP was loaded on a column packed with ALP/gellan-chitosan capsules at 27 degrees C, approximately 75% of p-NPP was hydrolyzed by passing through the column. No significant leakage of ALP was observed during the procedure, indicating that the capsules were resistant to pressure in the chromatographic operation. Furthermore, 70% of the hydrolytic activity of the packed capsules remained after storage at 4 degrees C for one month. These results suggest that the polyion complex capsules could be useful materials for protein fixation without chemical modification. [Diagram: see text] Encapsulation of ALP into PIC capsules and the morphological changes seen in the absence of the ALP substrate and in the presence of p-NPP and BICP.

Alkaline Phosphatase↗
PubMed2005

Association of Ets-related transcriptional factor E1AF expression with overexpression of matrix metalloproteinases, COX-2 and iNOS in the early stage of colorectal carcinogenesis.

It is now becoming clear that matrix metalloproteinases (MMPs) play a key role in tumor development and growth. MMPs are overexpressed in a variety of premalignant tumor tissues, including colorectal adenoma. Little is known about the mechanisms underlying the overexpression of MMPs in adenoma tissues. E1AF, an Ets family transcriptional factor, has been shown to play an important role in the expression of MMPs and cyclooxygenase-2 (COX-2) in advanced colorectal cancers. The aim of this study was to examine the E1AF expression and determine whether it is correlated with the expression of MMPs, COX-2 and inducible nitric oxide synthase (iNOS) in human colorectal adenoma and submucosal cancer (pT1). Using the semi-quantitative RT-PCR, 90 colorectal tumors, including 63 adenomas and 27 cancers (pT1), were analyzed for the expression of E1AF, MMPs, COX-2 and iNOS. Immunohistochemical analysis and in vitro transfection assays were also performed. E1AF mRNA was detected in 43 (47.8%) of the 90 colorectal tumors. E1AF overexpression was significantly correlated with histopathology. E1AF expression was correlated significantly with the expression of MMP-1 and MMP-7. Overexpression of COX-2 and iNOS mRNA expression was observed in 42.2% and 66.7% of the 90 colorectal tumors, respectively. COX-2 was correlated significantly with size, gender, histopathology and E1AF. iNOS was correlated significantly with size, histopathology, E1AF and COX-2. The correlation of E1AF expression with COX-2 and iNOS expression was also demonstrated by immunohistochemistry. Northern blot analysis of transfectants showed the effect of E1AF on COX-2 expression as well as iNOS on E1AF/COX-2 expression in colon cancer cell lines. The results suggest that E1AF, in conjunction with the expression of MMP-1, MMP-7, COX-2 and iNOS, plays an important role in the early stage of colorectal carcinogenesis.

Adenovirus E1A Proteins↗
PubMed2005

Measurement of Pseudomonas aeruginosa multidrug efflux pumps by quantitative real-time polymerase chain reaction.

Multidrug efflux pumps contribute to multiple antibiotic resistance in Pseudomonas aeruginosa. Pump expression usually has been quantified by Western blotting. Quantitative real-time polymerase chain reaction has been developed to measure mRNA expression for genes of interest. Whether this method correlates with pump protein quantities is unclear. We devised a real-time PCR for mRNA expression of MexAB-OprM and MexXY-OprM multidrug efflux pumps. In laboratory strains differing in MexB and MexY expression and in several clinical isolates, protein and mRNA expression correlated well. Quantitative real-time PCR should be a useful alternative in quantitating expression of multidrug efflux pumps by P. aeruginosa isolates in clinical laboratories.

Bacterial Outer Membrane Proteins↗