ABSTRACT
The objective of this research was to clone 1-deoxy-D-xylulose 5-phosphate reductoisomerase gene (MoDXR) and its promoter sequence from Morinda officinalis and carry out bioinformatic analysis, cis-acting elements analysis, and prokaryotic expression. On the basis of the MoDXR gene sequence obtained from the M. officinalis transcriptome and with NCBI-ORFfinder analysis, a pair of specific primers were designed, and used for RT-PCR amplification. The promoter region sequence at the 5′ end of MoDXR gene was isolated by the genome walking technique. Localization of MoDXR was carried out by subcellular analysis. The prokaryotic expression plasmid pET-28a-MoDXR was constructed and transfected into Escherichia coli BL21(DE3) chemically-competent cells; the recombiant plasmid expressed fusion protein after the induction by IPTG. The full-length cDNA of MoDXR was 2 015 bp,and open reading frame (ORF) size was 1 425 bp, and it encoded 474 amino acid residues and had a molecular mass of 51.27 kD. Sequence comparison with BlastP to the NCBI database revealed that MoDXR had high sequence similarity with many other DXRs, such as Coffea arabica DXR (CaDXR) and Rauvolfia verticillata DXR (RvDXR). A phylogenetic tree revealed that MoDXR had its closest relationship with DXR from Coffea arabica and Gardenia jasminoides. The subcellular localization revealed that MoDXR protein was located on the chloroplast. Plantcare analysis indicated that the promoter region sequence of MoDXR was 1 493 bp, covering multiple light, stress, and hormone-responsive cis-regulatory elements; protein electrophoresis showed that the expressed protein was the anticipated size. This research lays the foundation for further purification and structural and functional characterization of the MoDXR protein.
ABSTRACT
<p><b>OBJECTIVE</b>To study the biodistribution of L-[S-methyl-(11)C]-methioine ((11)C-MET) and explore its clinical application in positron emission tomography (PET) for brain tumor detection.</p><p><b>METHODS</b>Twenty-four Wistar rats and divided into 6 equal groups and injected with (11)C-MET through the tail vein and killed by decollation at 5, 10, 20, 30 and 40 min after injection, respectively. The liver, brain, blood, heart, lung, kidney, and spleen were harvested to measure the radioactivity and calculate the biodistribution of (11)C-MET. PET imaging with (11)C-MET was performed in 6 normal volunteers and 30 patients with pathologically confirmed brain gliomas.</p><p><b>RESULTS AND CONCLUSION</b>(11)C-MET showed high blood uptake and a long retention in the tumor mass, therefore can be a valuable tracer for PET imaging of brain tumor and the hypophysis.</p>
Subject(s)
Adult , Aged , Animals , Female , Humans , Male , Middle Aged , Rats , Brain , Diagnostic Imaging , Metabolism , Pathology , Brain Neoplasms , Diagnosis , Diagnostic Imaging , Metabolism , Carbon Radioisotopes , Glioma , Diagnosis , Diagnostic Imaging , Metabolism , Injections, Intravenous , Positron-Emission Tomography , Methods , Radiopharmaceuticals , Pharmacokinetics , Rats, Wistar , Sensitivity and Specificity , Tissue Distribution , Vitamin U , PharmacokineticsABSTRACT
<p><b>BACKGROUND</b>Evaluation of fetal central nervous system (CNS) agenesis by ultrasonography (US) is frequently limited, but magnetic resonance imaging (MRI) has its own advantages and is gaining popularity in displaying suspected fetal anomalies. The purpose of this study was to explore the value of MRI in detecting fetal CNS agenesis.</p><p><b>METHODS</b>Thirty-four women (aged from 22 to 35 years, average 27 years) with complicated pregnancies (16 - 39 weeks of gestation, average 30 weeks) were examined with a 1.5 T superconductive MR unit within 24 hours after ultrasonography. Half-Fourier acquisition single-shot turbo spin-echo (HASTE) T(2)-weighted imaging (T(2)WI) sequence were performed in all patients, and fast low angle shot (FLASH) T(1)-weighted imaging (T(1)WI) sequence were applied sequentially in seven of them. Comparison of the results was made between the MRI and US findings as well as autopsy or postnatal follow-up MRI findings.</p><p><b>RESULTS</b>The gyrus, sulcus, corpus callosum, thalamus, cerebellum, brainstem, and spinal cord of fetus were shown more clearly on T(2)-weighted MR images than on T(1)-weighted MR images. MRI corrected the diagnosis of US in 10 cases (10/34, 29.41%) and the diagnosis was missed only in 1 case (1/34, 2.94%).</p><p><b>CONCLUSION</b>MRI has advantages to US in detecting fetal CNS anomalies and is a supplement to US in complicated pregnancies.</p>