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mRNA Ratio (mrna + ratio)

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Medical Sciences80%

Selected Abstracts

Effect of lactational exposure to 1,2,3,4- tetrachlorodibenzo-p-dioxin on cytochrome P-450 1A1 mRNA in the neonatal rat liver: Quantitative analysis by the competitive RT-PCR method

PEDIATRICS INTERNATIONAL, Issue 5 2001
Yumi Kono
AbstractBackground and Methods: The aim of this study was to assess the effect of lactational exposure to dioxins in neonates on the cytochrome P450 1A1 (CYP1A1) induction in the level of gene expression. Maternal rats were treated with a single dose of 50 or 100 ,mol/kg 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TCDD), a low potent congener of dioxins, on the first day post-partum (day 1). Induction of CYP1A1 mRNA expression was quantitatively analyzed by the competitive reverse transcription,polymerase chain reaction (RT,PCR) method. Results: The CYP1A1 mRNA was detectable at extremely low amounts in the liver of control neonates and mothers. The mRNA ratios of CYP1A1 to ,-actin in neonates were dose-dependently increased by the treatment of 1,2,3,4-TCDD of their mothers. Its peak occurred on day 6 and was sustained at the same level on day 10. Increases of the ratio with 100 ,mol/kg 1,2,3,4-TCDD on day 2, 6 and 10 were 26-, 40- and 40-fold of the appropriate controls, respectively. These levels paralleled the activity of ethoxyresorufin-o-deethylase, representing CYP1A mediated monooxygenase. In the mother, the mRNA ratio was increased only to threefold of the control, 10 days after treatment. Conclusion: Current RT-PCR procedure enabled to assess both constitutive and induced levels of CYP1A1 mRNA in the neonatal rat livers. Although the dose of 1,2,3,4-TCDD selected in this study was about 5000 times higher than the daily intake of dioxins in breast-fed infants, CYP1A1 mRNA was highly induced for a longer period of time in neonatal rats receiving 1,2,3,4-TCDD via lactation than the treated maternal rats. [source]

Preventive effect of hochu-ekki-to, a Japanese herbal medicine, on bleomycin-induced lung injury in mice

RESPIROLOGY, Issue 6 2007
Shunji TAJIMA
Objective: Pulmonary fibrosis is thought to be closely associated with the T-helper type-2 (Th2) immune response. Recent studies have shown that hochu-ekki-to (TJ-41), a Japanese herbal medicine, may correct the Th1/Th2 imbalance skewed to Th2. The present study was designed to investigate the preventive effect of TJ-41 on the development of bleomycin (BLM)-induced lung injury in mice. Methods: Female C57BL/6 mice were divided into a group given ordinary feed and another group given the same feed plus TJ-41 mixed in at a dose of 1 g/kg/day. Both groups were maintained on this diet for 8 weeks before and 5 weeks after administration of 2 mg/kg BLM intratracheally. Results: Mortality after BLM-induced lung injury was significantly lower in the TJ-41-treated mice. The hydroxyproline content and fluid content in the lung on day 35 was significantly lower in the TJ-41-treated mice. Histologically, TJ-41 reduced the number of infiltrating cells, thus ameliorating the destruction of the lung architecture, and attenuated the lung fibrosis score. Furthermore, TJ-41 inhibited the expression of the interleukin-5/interferon-, mRNA ratio in the lung on day 7. Conclusions: Treatment with TJ-41 partially prevented experimental lung fibrosis through the correction of the Th1/Th2 imbalance skewed to Th2. [source]

Possible predictive factors for ICSI?

ANDROLOGIA, Issue 4 2003
Molecular biology techniques in combination with therapeutic testicular biopsies
Summary. Applying intracytoplasmic sperm injection (ICSI), the selection of an unsuccessful spermatozoon results in great emotional consequences for the couple. Therefore, there is a need for a prognostic parameter to estimate their chances for successful fertility treatment. This review summarizes both the main reasons for spermatogenic impairment, and possible predictive factors for successful sperm retrieval applying testicular sperm extraction and outcome of ICSI. While basic sperm parameters, aetiology and type of spermatozoa, and serum follicle-stimulating hormone and inhibin levels have been shown to be unrelated to the outcome of ICSI, Y-chromosome microdeletions are known to have a negative influence on the fertilizing capacity of spermatozoa. Recently, a significant correlation has been reported between the protamine-1 to protamine-2 mRNA ratio in haploid spermatids of testicular biopsies and the ability of spermatozoa for successful fertilization of an oocyte. In future, both the outstanding role of the haploid spermatids and the involvement of molecular biological techniques will improve the role of therapeutic testicular biopsies. [source]

Fast set-up of doxycycline-inducible protein expression in human cell lines with a single plasmid based on Epstein,Barr virus replication and the simple tetracycline repressor

FEBS JOURNAL, Issue 3 2007
Markus Bach
We have developed a novel plasmid vector, pEBTetD, for full establishment of doxycycline-inducible protein expression by just a single transfection. pEBTetD contains an Epstein,Barr virus origin of replication for stable and efficient episomal propagation in human cell lines, a cassette for continuous expression of the simple tetracycline repressor, and a cytomegalovirus-type 2 tetracycline operator (tetO2)-tetO2 promoter. As there is no integration of vector into the genome, clonal isolation of transfected cells is not necessary. Cells are thus ready for use 1 week after transfection; this contrasts with 3,12 weeks for other systems. Adequate regulation of protein expression was accomplished by abrogation of mRNA polyadenylation. In northern analysis of seven cDNAs coding for transport proteins, pools of transfected human embryonic kidney 293 cells showed on/off mRNA ratios in the order of 100 : 1. Cell pools were also analyzed for regulation of protein function. With two transport proteins of the plasma membrane, the on/off activity ratios were 24 : 1 and 34 : 1, respectively. With enhanced green fluorescent protein, a 23 : 1 ratio was observed based on fluorescence intensity data from flow cytometry. The unique advantage of our system rests on the unmodified tetracycline repressor, which is less likely, by relocation upon binding of doxycycline, to cause cellular disturbances than chimera of tetracycline repressor and eukaryotic transactivation domains. Thus, in a comprehensive comparison of on- and off-states, a steady cellular background is provided. Finally, in contrast to a system based on Flp recombinase, the set-up of our system is inherently reliable. [source]

A novel beta-delta globin gene fusion, anti-Lepore Hong Kong, leads to overexpression of delta globin chain and a mild thalassaemia intermedia phenotype when co-inherited with ,0 -thalassaemia

BRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2007
Chi-Chiu So
Summary Anti-Lepore haemoglobins (Hb) are rare ,, fusion variants that arise from non-homologous crossover during meiosis, resulting in a ,,,,,, configuration. A novel anti-Lepore mutation (anti-Lepore Hong Kong) was found in two Chinese families with raised Hb A2. Direct sequencing revealed a crossover within a 54-bp region spanning the junction of cap site (CAP) and exon 1, which predicted the production of normal , -globin. Determination of ,/, -mRNA ratios by quantitative real-time polymerase chain reaction demonstrated downregulation of the , gene in cis due to the interposed ,, fusion gene. Although heterozygotes have normal red cell indices and are clinically silent, compound heterozygotes with ,0 mutation in trans produce a mild thalassaemia intermedia phenotype with a markedly raised Hb A2 level that may mimic clinically mild Hb E- ,+ -thalassaemia. Awareness of the presence of anti-Lepore Hong Kong will help to resolve diagnostic problems in regions with significant prevalence of globin disorders. [source]