AIM To study the effect of dl-3-n-butylphthalide (dl-NBP) on arachidonic acid(AA) release and phospholipase A2 (PLA2) mRNA in cerebral cortex of rats subjected to focal cerebral ischemia. METHODS Focal cerebral ischemia was induced by inserting a monofilament nylon suture into the internal carotid artery and blocking the origin of the middle cerebral artery. AA was determined with high performance liquid chromatography (HPLC). The PLA2 mRNA expression was evaluated by Northern blot analysis. RESULTS Six hours of cerebral ischemia induced AA release in the ischemic cerebral cortex. dl-NBP (10 or 20 mg·kg-1) and nimodipine (0.5 mg·kg-1) given intraperitoneally 5 min and 120 min again after the onset of ischemia significantly reduced AA concentration in the cerebral cortex (P<0.01). d-NBP, but not l-NBP, decreased AA release in the brain after middle cerebral artery occlusion. The expression of PLA2 mRNA in cerebral cortex induced by cerebral ischemia was also inhibited by dl-NBP and d-NBP (10 or 20 mg·kg-1, ip). CONCLUSION dl-NBP and d-NBP inhibited AA release and PLA2 mRNA expression in the ischemic brain tissue in vivo.

Objective To construct the human osteoblast-like cell model with estrogen receptor α(ERα)subunit gene knocked down. Methods According to the computer-aided design(CAD),ERα-specific small interference RNA(siRNA)gene was synthesized and cloned into the expression vector pSilencer 4.1-CMV. The recombinant ERα siRNA plasmid was transfected into human osteoblast-like cell line MG63 by lipofectin,the cloned MG63 ceils were selected by hygromycin,and the cloned MG63 cell was cultured more than 20 passages after transfection.The expression of ERα mRNA in MG63 cells was detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression and location of ERα protein were identified by immunocytochemistry.Compared with control groups,proliferation rate,growth cycle and expression did not show significant difference.Results The recombinant eukaryote plasmid vector was constructed.Furthermore,the recombinant plasmid knocked down ERα protein in human osteoblast-like cells. Conclusions The human osteoblast-like cell model with RNAi-knocked down ERα gene is constructed successfully.This model appears to be very useful for the future research on ERα biological characters and on molecular mechanism of bone metabolism.

4-Hydroxybenzoate (4HBA) is an important chemical compound used for synthesis of liquid crystal. Production of 4HBA from renewable resources is an effective mean to solve problems such as environmental pollution and petroleum shortage. This review briefly introduces the chemical synthesis of 4HBA from oil compounds, and mainly describes the progress in 4HBA biosynthesis from renewable resources by plants and microorganisms. In most intriguing aspect of plant-based synthesis of 4HBA is the appeal of directly synthesizing a chemical from CO2. However, the glucosylation system in plant cells converting 4HBA to glucose conjugates, causing the post treatment a problem. The recombinant microorganisms produce pure 4HBA, but less efficient. A new strain of Microbulbifer has ability to naturally accumulate 4HBA from glucose. Elucidation of the metabolic pathways and regulation systems would improve 4HBA synthesis efficiency.
Alteromonadaceae ; metabolism ; Glucose ; chemistry ; Glycosylation ; Industrial Microbiology ; Metabolic Networks and Pathways ; Parabens ; metabolism ; Plants ; metabolism

BACKGROUND:One-hole split endoscope technique has been widely used in the treatment of lumbar degenerative diseases,but there is no relevant literature on the safety analysis of this technique in the treatment of upper lumbar disc herniation. OBJECTIVE:To observe the position relationship of nerve roots,intervertebral space and bone landmarks in the upper lumbar spine by three-dimensional lumbar CT reconstruction technology,and to provide a basis for the clinical operation of one-hole split endoscope surgery. METHODS:Twenty-six patients with upper lumbar disc herniation underwent a lumbar CT scan.Mimics 17.0 software was imported to measure the related imaging parameters of L1/2 to L3/4 segments:(1)Measurement of vertical distance:In coronal view,the distance(a)from the intersection point of the medial facet of the superior articular process and the superior endplate(N)to the apex of the articular process(S);in the coronal view,the distance(b)from the sagittal intersection(M)of N and the inferior endplate to the apex of the inferior articular process(X).(2)Measured horizontal distance:the distance(c)between the cross-section of N and the lower edge of the outlet nerve root(N2);distance(d)between the cross-section of N and the intersection point of neural tissue(N1);N1 to N2 distance(e);distance(f)between the cross-section of M and the lateral edge of the nerve tissue(M1);M to M cross-section and exit nerve root intersection(M2)distance(g);distance(h)from M1 to M2;distance(i)from M2 to N1;distance(j)from the posterior edge of the articular surface(R)to M2 in sagittal view of the superior articular process. RESULTS AND CONCLUSION:(1)With the decrease of the segment,the distances a and b gradually increased,and the distance j gradually decreased.There was no significant difference between L1/2 and L2/3 segments(P>0.05).(2)With the decrease of the segment,distance d first decreased and then increased;distance f gradually decreased;distances c,e,g,h and i gradually increased;and there was no significant difference between L2/3 and L3/4 segments(P>0.05).(3)Distance i was the shortest distance without pulling nerve roots in the natural state,and the area of the safety zone was between four points M1,M2,N1,and N2.The bone was removed to the upper and lower endplates by biting the bone downward and upward through S and X,respectively,to expose the intervertebral space,and the window of distance g to M2 could be opened outward to avoid injury of the outlet nerve roots.(4)In conclusion,the upper lumbar vertebrae have unique anatomical characteristics.Based on the relevant measurements of nerve roots,spinal dura and intervertebral space,the parameters of the one-hole split endoscope technique are more accurate and safe during operation.