Real-time Reverse Transcriptase Polymerase Chain Reaction (real-time + reverse_transcriptase_polymerase_chain_reaction)

Distribution by Scientific Domains


Selected Abstracts


Evaluation of a p30 Gene-Based Real-Time Reverse Transcriptase Polymerase Chain Reaction Assay for Detection of Feline Caliciviruses

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2004
Brian A. Scansen
This report describes a feline calicivirus (FCV) p30 gene-based real-time SYBR Green I reverse transcriptase polymerase chain reaction (RT-PCR) assay that is capable of detecting low virus concentrations and a broad range of FCV isolates. The assay consisted of a 1-step RT-PCR reaction with primers delineating a 126-base-pair (bp) region of the FCV p30 gene. Sensitivity of the RT-PCR assay was determined to be equivalent to a FCV titer of 1.2 × 101 to 1.2 × 102 TCID50/mL. The assay was linear over a wide range of template concentrations and had a reaction efficiency of 95%. Specific FCV amplification products were detected from 51 wild-type FCV isolates, whereas specific products were not detected from a canine calicivirus, a rabbit calicivirus, and a bovine calicivirus. The primers used in this study amplified a large number of North American FCV isolates and further confirm the diagnostic utility of p30 gene-based real-time RT-PCR for detection of FCV. [source]


The Effect of Betamethasone Treatment on Neuroactive Steroid Synthesis in a Foetal Guinea Pig Model of Growth Restriction

JOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2010
A. A. McKendry
There are ongoing concerns that antenatal corticosteroids, which are administered to women at high risk of delivering preterm to reduce the incidence of respiratory distress syndrome, have adverse effects on foetal brain development and subsequent effects on behaviour and learning, when administered as repeated courses. The present study aimed to examine whether repeated betamethasone treatment alters the expression of the key-rate limiting enzyme, 5,-reductase, in the synthetic pathway of the potent neuroactive steroid allopregnanolone in the brain and placenta and whether this effect is potentiated in growth restricted foetuses. To investigate this, pregnant guinea pigs carrying either control (sham surgery) or growth-restricted foetuses were treated with vehicle or betamethasone (1 mg/kg/day) for 4 days prior to sacrifice (65d). Placental insufficiency was induced by the ablation of uterine artery branches supplying each placenta at mid gestation, resulting in foetal growth restriction characterised by ,brain sparing'. Real-time reverse transcriptase polymerase chain reaction was used to determine relative 5,-reductase type 1 and 2 mRNA expression in the placenta and brain. Immunohistochemistry was used to examine the glial fibrillary acidic protein (GFAP) expression in the subcortical white matter, CA1 and dentate regions of the hippocampus. 5,-reductase type 2 mRNA expression in the brain was markedly reduced by betamethasone treatment in male foetuses compared to vehicle-treated controls but not in female foetuses. In addition, 5,-reductase type 1 expression in the brain was increased by growth restriction and/or betamethasone treatment in female foetuses but expression in males foetuses did not increase. 5,-reductase type 2 expression in the placenta was markedly reduced by betamethasone treatment compared to vehicle-treated control. Intrauterine growth restriction and betamethasone treatment reduced GFAP expression in the CA1 region of the hippocampus in the brains of male but not female foetuses. These data indicate that betamethasone treatment suppresses placental expression and has sexually dimorphic effects on expression of neuroactive steroid synthetic enzymes in the brain. These actions may lead to adverse effects on the developing brain, particularly in male foetuses, such as the observed effects on GFAP expression. [source]


Cell density- and ComE-dependent expression of a group of mutacin and mutacin-like genes in Streptococcus mutans

FEMS MICROBIOLOGY LETTERS, Issue 1 2006
Jens Kreth
Abstract Streptococcus mutans is a major cariogenic inhabitant of the high cell density oral biofilm (dental plaque). In previous studies, we showed that production of one of its virulence factors, the bacteriocin mutacin IV, was regulated by high cell density as well as the competence regulatory system ComED. In this study, we utilized luciferase fusions and real-time reverse transcriptase polymerase chain reaction (RT-PCR), to demonstrate that high cell density and ComED also regulate an uncharacterized group of mutacin and mutacin-like genes. Under high cell density or in the presence of externally added competence-stimulating peptide (CSP), gene expression increased 10- to 30-fold. Interestingly, high cell density was able to bypass the requirement for CSP addition. However, both cell density and CSP-dependent gene expression had a strict requirement for the ComE response regulator. [source]


Strain- and region-specific gene expression profiles in mouse brain in response to chronic nicotine treatment

GENES, BRAIN AND BEHAVIOR, Issue 1 2008
J. Wang
A pathway-focused complementary DNA microarray and gene ontology analysis were used to investigate gene expression profiles in the amygdala, hippocampus, nucleus accumbens, prefrontal cortex (PFC) and ventral tegmental area of C3H/HeJ and C57BL/6J mice receiving nicotine in drinking water (100 ,g/ml in 2% saccharin for 2 weeks). A balanced experimental design and rigorous statistical analysis have led to the identification of 3.5,22.1% and 4.1,14.3% of the 638 sequence-verified genes as significantly modulated in the aforementioned brain regions of the C3H/HeJ and C57BL/6J strains, respectively. Comparisons of differential expression among brain tissues showed that only a small number of genes were altered in multiple brain regions, suggesting presence of a brain region-specific transcriptional response to nicotine. Subsequent principal component analysis and Expression Analysis Systematic Explorer analysis showed significant enrichment of biological processes both in C3H/HeJ and C57BL/6J mice, i.e. cell cycle/proliferation, organogenesis and transmission of nerve impulse. Finally, we verified the observed changes in expression using real-time reverse transcriptase polymerase chain reaction for six representative genes in the PFC region, providing an independent replication of our microarray results. Together, this report represents the first comprehensive gene expression profiling investigation of the changes caused by nicotine in brain tissues of the two mouse strains known to exhibit differential behavioral and physiological responses to nicotine. [source]


Preventive effects of ME3738 on hepatic fibrosis induced by bile duct ligation in rats

HEPATOLOGY RESEARCH, Issue 7 2008
Kazunori Maeda
Aim:, The aim of this study was to examine the preventive effects of ME3738 on hepatic fibrosis induced by bile duct ligation (BDL) in rats. Methods:, ME3738 (20 mg/day) was administered orally for 21 days immediately after BDL. Fibrosis was assessed by measuring hepatic hydroxyproline (Hyp) content. Activated hepatic stellate cells (HSCs) were assessed by ,-smooth muscle actin (,-SMA) immunostaining. Hepatic thiobarbituric acid-reactive substance (TBARS), 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxy-2-deoxyguanosine (8-OHdG) immunostaining were used to analyze oxidative stress. The gene expressions of collagen-I, transforming growth factor-,1 (TGF-,1), tissue inhibitor of metalloproteinases-1 (TIMP-1), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) in the liver were examined by real-time reverse transcriptase polymerase chain reaction (RT,PCR). Results:, Hepatic Hyp content and the area of hepatic fibrosis in BDL rats treated with ME3738 were reduced by 24% and 39% compared with non-treated BDL rats (hepatic Hyp, 9.40 ± 2.85 vs. 12.39 ± 3.91 mg/liver; P = 0.036; area of hepatic fibrosis, 13.1 ± 3.8 vs. 21.5 ± 10.9; P = 0.045). Furthermore, ,-SMA-positive cells were significantly reduced by 40% (22.3 ± 14.8 vs. 37.6 ± 14.2; P = 0.011), collagen-I mRNA by 83% (6.5 ± 2.2 vs. 38.3 ± 9.1; P = 0.002), HO-1 mRNA by 58% (4.13 ± 1.22 vs. 9.73 ± 1.80; P = 0.018) and hepatic HO-1 content by 26% (2.13 ± 0.80 vs. 2.87 ± 0.19; P = 0.01) following ME3738 treatment. The hepatic expression of TBARS, 4-HNE, 8-OHdG and mRNA levels of TGF-,1, TIMP-1 and IL-6 in the liver were unchanged by ME3738 treatment. Conclusion:, Oral ME3738 administration may prevent the progression of hepatic fibrosis in BDL rats through suppression of the activation and collagen synthesis of HSC and, in part, oxidative stress. ME3738 has potential as a therapeutic drug for cholestatic liver fibrosis. [source]


MicroRNA-10b is overexpressed in malignant glioma and associated with tumor invasive factors, uPAR and RhoC

INTERNATIONAL JOURNAL OF CANCER, Issue 6 2009
Takashi Sasayama
Abstract MicroRNAs (miRNAs) are effective post-transcriptional regulators of gene expression and are important in many biological processes. Although the oncogenic and tumor suppressive functions of several miRNAs have been characterized, the role of miRNAs in mediating tumor invasion and migration remains largely unexplored. Recently, miR-10b was identified as an miRNA highly expressed in metastatic breast cancer, promoting cell migration and invasion. Here, we performed real-time reverse transcriptase polymerase chain reaction (RT-PCR) assays on 43 glioma samples (17 glioblastoma, 6 anaplastic astrocytoma, 10 low-grade astrocytoma, 6 oligodendroglioma and 4 ependymoma) and 6 glioma cell lines. We found that miR-10b expression was upregulated in all glioma samples compared to non-neoplastic brain tissues. The expression levels of miR-10b were associated with higher grade glioma. In addition, mRNA expressions of RhoC and urokinase-type plasminogen activator receptor (uPAR), which were thought to be regulated by miR-10b via HOXD10, were statistically significantly correlated with the expression of miR-10b (p < 0.001, p = 0.001, respectively). Also, protein expression levels of RhoC and uPAR were associated with expression levels of miR-10b (p = 0.009, p = 0.014, respectively). Finally, multifocal lesions on enhanced MRI of 7 malignant gliomas were associated with higher expression levels of miR-10b (p = 0.02). Our data indicated that miR-10b might play some role in the invasion of glioma cells. © 2009 UICC [source]


Suppression of nNOS expression in rat enteric neurones by the receptor for advanced glycation end-products

NEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2006
K. Korenaga
Abstract, Diabetes mellitus results in a loss of neuronal nitric oxide synthase (nNOS) expression in the myenteric plexus but the underlying mechanisms remain unknown. We hypothesized that this may be mediated by advanced glycation end-products (AGEs), a class of modified protein adducts formed by non-enzymatic glycation that interact with the receptor for AGE (RAGE) and which are important in the pathogenesis of other diabetic complications. Whole mount preparations of longitudinal muscles with adherent myenteric plexus (LM-MPs) from the duodenum of adult male rats were exposed to glycated bovines serum albumin (AGE-BSA) or BSA for 24 h. Western blotting, immunohistochemistry and real-time reverse transcriptase polymerase chain reaction (RT-PCR) for mRNA showed a significant reduction in nNOS expression in LM-MPs after exposure to AGE-BSA. NO release, as measured by the Griess reaction, was also significantly reduced by AGE-BSA. A neutralizing antibody against RAGE attenuated the reduction of nNOS protein caused by AGE-BSA. Immunohistochemistry revealed co-localization of RAGE expression with Hu, a marker for neuronal cells but not for S-100, a glial marker. Advanced glycation end-products reduce nNOS expression in the rat myenteric neurones acting via the receptor RAGE. Our results suggest novel pathways for disruption of the nitrergic phenotype in diabetes. [source]


Gibberellins, jasmonate and abscisic acid modulate the sucrose-induced expression of anthocyanin biosynthetic genes in Arabidopsis

NEW PHYTOLOGIST, Issue 4 2008
Elena Loreti
Summary ,,Anthocyanins are secondary metabolites, which play an important role in the physiology of plants. Both sucrose and hormones regulate anthocyanin synthesis. Here, the interplay between sucrose and plant hormones was investigated in the expression of sucrose-regulated genes coding for anthocyanin biosynthetic enzymes in Arabidopsis seedlings. ,,The expression pattern of 14 genes involved in the anthocyanin biosynthetic pathway, including two transcription factors (PAP1, PAP2), was analysed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in Arabidopsis seedlings treated with sucrose and plant hormones. ,,Sucrose-induction of the anthocyanin synthesis pathway was repressed by the addition of gibberellic acid (GA) whereas jasmonate (JA) and abscisic acid (ABA) had a synergic effect with sucrose. The gai mutant was less sensitive to GA-dependent repression of dihydroflavonol reductase. This would seem to prove that GAI signalling is involved in the crosstalk between sucrose and GA in wild-type Arabidopsis seedlings. Conversely, the inductive effect of sucrose was not strictly ABA mediated. Sucrose induction of anthocyanin genes required the COI1 gene, but not JAR1, which suggests a possible convergence of the jasmonate- and sucrose-signalling pathways. ,,The results suggest the existence of a crosstalk between the sucrose and hormone signalling pathways in the regulation of the anthocyanin biosynthetic pathway. [source]


Transcriptome analysis of bud burst in sessile oak (Quercus petraea)

NEW PHYTOLOGIST, Issue 4 2006
Jérémy Derory
Summary ,,Expression patterns of hundreds of transcripts in apical buds were monitored during bud flushing in sessile oak (Quercus petraea), in order to identify genes differentially expressed between the quiescent and active stage of bud development. ,,Different transcriptomic techniques combining the construction of suppression subtractive hybridization (SSH) libraries and the monitoring of gene expression using macroarray and real-time reverse transcriptase polymerase chain reaction (RT-PCR) were performed to dissect bud burst, with a special emphasis on the onset of the process. ,,We generated 801 expressed sequence tags (ESTs) derived from six developmental stages of bud burst. Macroarray experiment revealed a total of 233 unique transcripts exhibiting differential expression during the process, and a putative function was assigned to 65% of them. Cell rescue/defense-, metabolism-, protein synthesis-, cell cycle- and transcription-related transcripts were among the most regulated genes. Macroarray and real-time RT-PCR showed that several genes exhibited contrasted expressions between quiescent and swelling buds, such as a putative homologue of the transcription factor DAG2 (Dof Affecting Germination 2), previously reported to be involved in the control of seed germination in Arabidopsis thaliana. ,,These differentially expressed genes constitute relevant candidates for signaling pathway of bud burst in trees. [source]


Analysis of Testosterone Effects on Sonic Hedgehog Signaling in Juvenile, Adolescent and Adult Sprague Dawley Rat Penis

THE JOURNAL OF SEXUAL MEDICINE, Issue 3 2010
Christopher W. Bond MS
ABSTRACT Introduction., Smooth muscle apoptosis is a major contributing factor to erectile dysfunction (ED) development in prostatectomy and diabetic patients and animal models. A critical regulator of penile smooth muscle and apoptosis is Sonic hedgehog (SHH). The SHH protein is decreased in ED models and SHH treatment of cavernous nerve (CN) injured rats prevents smooth muscle apoptosis. A close association between androgen deficiency and ED has been suggested in the literature, but few studies have examined the molecular effects on penile smooth muscle and on known signaling mechanisms that regulate morphology. Aim., Examine testosterone and SHH interaction in eugonadal adult, adolescent and juvenile rats by performing castration studies and treatment with supraphysiological testosterone. Methods., The eugonadal adult Sprague Dawley rats were either treated with testosterone for 7 or 14 days (N = 14) or were castrated for 4 or 7 days (N = 12). The juvenile rats were treated with testosterone for 8 days (N = 7). The adolescent rats were castrated and sacrificed at P88 (N = 8). The control rats had empty vehicle (N = 22) or sham surgery (N = 20). Main Outcome Measures., The active form of SHH protein and mRNA were quantified by semi-quantitative immunohistochemical analysis and real-time reverse transcriptase polymerase chain reaction (RT-PCR). Results., Testosterone treatment did not alter SHH signaling in juvenile rats. Shh mRNA increased 3.2-fold and SHH protein increased 1.2-fold in rats castrated during puberty. In adult rats, castration decreased Shh mRNA 3.2-fold but did not alter SHH protein. Testosterone supplement in adult rats increased Shh mRNA 2.3-fold and decreased SHH protein 1.3-fold. Conclusions., SHH signaling is independent of testosterone in normal juvenile rats and is sensitive to testosterone during adolescence, while testosterone supplement in the adult adversely impacts SHH signaling in a very similar manner to that observed with CN injury. Bond CW, Angeloni NL, and Podlasek CA. Analysis of testosterone effects on sonic hedgehog signaling in juvenile, adolescent and adult Sprague Dawley rat penis. J Sex Med 2010;7:1116,1125. [source]


Improved sensitivity for detecting micrometastases in pelvic lymph nodes by real-time reverse transcriptase polymerase chain reaction (RT-PCR) compared with conventional RT-PCR in patients with clinically localized prostate cancer undergoing radical prostatectomy

BJU INTERNATIONAL, Issue 8 2009
Tomoaki Terakawa
OBJECTIVE To compare the usefulness between real-time reverse transcriptase polymerase chain reaction (RT-PCR) with that of conventional RT-PCR for detecting micrometastases in pelvic lymph nodes (PLN) dissected during radical prostatectomy (RP) for prostate cancer. PATIENTS AND METHODS In all, 120 patients with clinically localized prostate cancer who underwent RP and pelvic lymphadenectomy were included. Expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) in 2215 PLNs obtained from these 120 patients were assessed by fully quantitative real-time RT-PCR and as well as conventional RT-PCR. Specimens, in which either PSA or PSMA mRNA was positive, were regarded as showing the ,presence of micrometastasis'. RESULTS Pathological examinations detected tumour cells in 29 PLNs from 11 patients, while real-time RT-PCR and conventional RT-PCR further identified micrometastasis in 143 and 81 PLNs from 32 and 19 patients, respectively, with no pathological evidence of nodal involvement; that is, the sensitivity of real-time RT-PCR for detecting micrometastases was significantly higher than that of conventional RT-PCR. In this series, biochemical recurrence occurred in 32 patients, and in both assays, there were significant differences in biochemical recurrence-free survival between patients with and with no micrometastases. However, despite the significant association of micrometastases detected by both assays with biochemical recurrence on univariate analysis, the presence of micrometastases detected by real-time RT-PCR but not that detected by conventional RT-PCR appeared to be useful as an independent predictor on multivariate analysis. CONCLUSIONS Although micrometastatic tumour foci in PLNs that were missed by routine pathological examination could be diagnosed by both real-time RT-PCR and conventional RT-PCR assays, it would be strongly recommended to use real-time RT-PCR to detect micrometastases considering its high sensitivity and the close association between the outcome of this assay and the probability of biochemical recurrence. [source]


Significance of micrometastases in pelvic lymph nodes detected by real-time reverse transcriptase polymerase chain reaction in patients with clinically localized prostate cancer undergoing radical prostatectomy after neoadjuvant hormonal therapy

BJU INTERNATIONAL, Issue 2 2007
Hideaki Miyake
OBJECTIVE To clarify the significance of micrometastases in pelvic lymph nodes in patients treated by radical prostatectomy (RP) for prostate cancer after neoadjuvant hormonal therapy (NHT). PATIENTS AND METHODS The study included 52 patients with clinically localized prostate cancer who received NHT followed by RP. The expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) in 989 lymph nodes isolated from the 52 patients were assessed by a fully quantitative real-time reverse-transcriptase polymerase chain reaction (RT-PCR). We regarded specimens in which either PSA or PSMA mRNA were positive as showing the ,presence of micrometastasis'. Lymph node specimens were also stained immunohistochemically with an antibody against PSA. RESULTS Pathological examinations detected tumour cells in 11 lymph nodes from four patients, and real-time RT-PCR further identified micrometastasis in 40 lymph nodes from 19 patients with no pathological evidence of nodal involvement. The presence of micrometastatic cancer cells was confirmed by immunohistochemical staining in 19 lymph nodes from 11 patients with pathologically negative nodes. The presence of micrometastases was significantly associated with other conventional prognostic variables, including the pretreatment serum PSA level, biopsy Gleason score and surgical margin status. The biochemical recurrence-free survival rate in patients with no micrometastasis was significantly higher than that in those with micrometastasis. Furthermore, multivariate analysis identified the presence of micrometastasis as an independent factor predicting biochemical recurrence. CONCLUSIONS Although residual foci of atrophic prostate cancer cells in resected lymph nodes after NHT can be difficult to diagnose by routine pathological examination, the present results show the usefulness of quantitative real-time RT-PCR targeting PSA and PSMA genes for detecting micrometastatic tumour foci in pelvic lymph nodes from patients with localized prostate cancer treated by NHT followed by RP. Furthermore, the present findings suggest that micrometastases in pelvic lymph nodes might be, at least partly, important in the development of biochemical recurrence in some patients undergoing RP after NHT. [source]


Cyclophilin A is overexpressed in human pancreatic cancer cells and stimulates cell proliferation through CD147

CANCER, Issue 10 2006
Min Li Ph.D.
Abstract BACKGROUND Although overexpression of cyclophilin A (CypA) is associated with several types of cancer, its role in pancreatic cancer has not been studied. In this study the expression of CypA and its receptor CD147 on pancreatic cancer was determined as well as the effect of exogenous CypA on pancreatic cancer cell proliferation. METHODS The expression of CypA and CD147 in human pancreatic cancer cell lines and tissues was determined with real-time reverse transcriptase polymerase chain reaction (RT-PCR), Western blot, and immunostaining. Cell proliferation in response to CypA was performed by [3H]thymidine incorporation assay. Phosphorylation of MAPK and cytokine secretion profiles in pancreatic cancer cells were determined by using the Bio-Plex phosphoprotein assay and cytokine assay. RESULTS Pancreatic cancer cell lines expressed significantly higher levels of CypA and CD147 than normal human pancreatic ductal epithelium (HPDE) cells. Expression of CypA and CD147 was also substantially higher in human pancreatic adenocarcinoma tissues than those in normal pancreatic tissues. Addition of exogenous CypA significantly stimulated pancreatic cancer cell proliferation in a dose-dependent manner and this effect was effectively blocked by pretreatment with anti-CD147 antibody. In addition, CypA activated ERK1/2 and p38 MAPK signaling pathways and increased the secretion of 2 key cytokines IL-5 and IL-17 in Panc-1 cells. CONCLUSIONS The expression of CypA and CD147 was significantly increased in both pancreatic cancer cell lines and tissues. Exogenous CypA promotes pancreatic cancer cell growth, which may be mediated through the interaction with CD147 and the activation of ERK1/2 and p38 MAPKs. Cancer 2006. © 2006 American Cancer Society. [source]