Study of peroxisome proliferator-activated receptor-γ coactivator-1α expression and cytoapoptosis in masseter muscles of unilateral chewing rat / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the changes of peroxisome proliferator- activated receptor-γ coactivator -1α (PGC-1α) mRNA and cytoapoptosis in the rats' masseter muscle which had been influenced by unilateral chewing, and to explore the theoretical foundation of changes in masticatory muscles induced by unilateral chewing.</p><p><b>METHODS</b>The animal models were established by extracting the Wistar rats' left maxillary molars. Thirty- six female Wistar rats were randomly divided into four groups of 2, 4, 6 and 8 weeks, nine each. In each group there were six rats with molar extracted and three as control. The Ca²⁺ level was detected by atomic spectrophotometric method. The relative expression of PGC-1α mRNA was detected by real- time fluorescent quantitative PCR. The apoptosis index was detected by Hoechst staining.</p><p><b>RESULTS</b>The Ca²⁺ level in the muscle on the extraction side were significantly higher than that in the controls in the beginning stage of unilateral chewing, and reached the peak at the 4th week [(43.62 ± 2.36) µg/g]. The relative expressions of PGC-1α increased from the beginning and reached the maximum level at the 4th week [extraction side: (1.57 ± 0.10); non-extraction side: (1.92 ± 0.06)], while the relative expressions of PGC-1α in 6 and 8 weeks decreased gradually [extraction side: (1.06 ± 0.08), (1.08 ± 0.07); non- extraction side: (1.09 ± 0.10), (1.11 ± 0.08)]. The changes of apoptosis index on non- extraction side increased continually and peaked at the 6th week [(38.56 ± 1.64)%].</p><p><b>CONCLUSIONS</b>PGC-1α and cytoapoptosis played important roles in different stages of tissue remodeling induced by unilateral chewing.</p>

Studies on the correlation between the expression of Toll-like receptor 4 and the synovitis of the temporomandibular joint in rats / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression of the Toll-like receptor-4 (TLR-4) in temporo-mandibular joint synovitis in rats, and to discuss the correlation between the expression of TLR-4 and the synovitis.</p><p><b>METHODS</b>Sixty male wistar rats were randomly divided into five groups, 12 each. Group A was the control group in which the rats were given normal diet.In Group B, the rats' bilateral masseter muscles were cut off (masseter resection group). In Group C, An cast metal crown were bonded on the mandibular right first molar of each rat (occlusal interference group). In Group D, occlusal pad were bonded on maxillary molars of each rat (occlusal dimension increase group). In Group E, rats' bilateral masseter muscles were re-sected and occlusal pads were bonded on their maxillary molars (masseter resection and occlusal dimension increase group). Pathological changes of synovium were observed using hematoxylin and eosin (HE) stains and pathology scores were evaluated. The expression of TLR- 4 were determined by immunohistochemical stains, and the expression of TLR-4 mRNA were determined by real-time PCR. The correlation between the expression of TLR-4, TLR-4 mRNA and the pathological score were analyzed using Spearman analysis.</p><p><b>RESULTS</b>The pathological scores of Group A-E were 0.5 ± 0.5, 2.5 ± 1.0, 2.7 ± 1.0, 3.0 ± 0.9, 5.3 ± 1.2 respectively. The expression of TLR-4 were (3.2 ± 1.5)%, (16.± 2.6)%, (15.8 ± 2.1)%, (17.5 ± 2.4)%, (38.2 ± 4.4) %. The expression of TLR-4 mRNA were 1.07 ± 0.09, 2.12 ± 0.33, 2.07 ± 0.29, 2.17 ± 0.34, 4.53 ± 0.46. Compared with group A, groups B- E showed significant higher pathology score (P < 0.05) and increased expression of both TLR-4 (P < 0.05) and TLR-4 mRNA (P < 0.05). An significant positive correlation was found between the expression of TLR- 4 and the pathology score (r = 0.785, P < 0.05), and between the expression of TLR- 4 mRNA and the pathology score (r = 0.720, P < 0.05).</p><p><b>CONCLUSIONS</b>TLR-4 may be closely associated with the development of the synovitis of TMJ of rats.</p>

Study on absorption ingredients of Plantaginis semen by in vitro everted intestinal sac method / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a method for quick investigating the absorption ingredients of Plantaginis semen and guiding the index selection for its quality control.</p><p><b>METHOD</b>The absorption of three concentrations of Plantaginis semem was investigated with the in vitro everted intestinal sac (VEIS) model The intestinal sac contents of jejunum and ileum were collected at different time and geniposidic acid was detected by HPLC and LC-MS(n) as the representative marker.</p><p><b>RESULT</b>Six ingredients could be detected. At different concentrations of Plantaginis semen, geniposidic acid tested by VEIS showed that there was a good linear correlation between the drug absorption from the medium across the intestinal epithelium into the sac contents in various intestines section. The absorption of the gut sacs from 0 to 90 min manifested a significant time-dependent manner. The Ka of geniposidic acid in the jejunum and ileum increased along with the raised dosage of the Plantaginis Semen (P < 0.05), which indicated a passive absorption manner.</p><p><b>CONCLUSION</b>This method can be used as a tool to investigate the absorption ingredients of Plantaginis Semen. Comparing with the jejunum, the ileum can provide more absorption information faster. The optimal incubation time in intestinal sac was 90 min.</p>

Quantitative analysis of four alkaloids in Xianglian preparations by QAMS method / 中国中药杂志

<p><b>OBJECTIVE</b>To examine the feasibilities of the method, quantitative analysis of multi-components by single marker (QAMS) for determination of four alkaloids in Xianglian preparations.</p><p><b>METHOD</b>A HPLC method was developed to determine the contents of four alkaloids, epiberberine, coptisine, palmatine and berberine in Xianglian preparations. Berberine was selected as the internal reference substance, and 3 relative correction factors to berberine were calculated. The contents of the four alkaloids in 16 batches of samples were determined by both external standard method and QAMS. The new method was evaluated by comparing the quantitative results with of the external standard method.</p><p><b>RESULT</b>No significant differences were found between the quantitative results of four alkaloids in 16 batches of samples determined by the two methods.</p><p><b>CONCLUSION</b>QAMS is feasible for determination of four alkaloids simultaneously, and the developed method can be used for quality control of Xiang Lian preparations.</p>

Numerical simulation of semi-circular section stent grafts / 中国组织工程研究

Geometrically virtual models of three-dimensional blood flow field and eight types of mesh stent (different porosity and different stent shape) were constructed using SoildWorks software, and simulation of stented models were performed respectively using finite element software ANSYS11.0 according to computation fluid dynamics method. The flow resistance of the semi-circular section stent model of blood flow from the semi-circular planar surface was greater than the reverse in a certain range of permeability. However, the result was the opposite when the porosity increased to a specific value. For both grid-stent model and sine-stent model, flow resistance of blood that flowed from the stent in both directions increased with the porosity reduction. Under the same porosity and the direction of blood flow from the same stent, the flow resistance of the grid stent model was 1.5 times greater than the sine-stent model. Results showed that there are different effects on the flow resistance in blood flow in different directions from the semi-circular section stent model.

Relation between frequent transient ischemic attacks and intracranial or extracranial artery lesions / 中华神经科杂志

Objective To investigate the relationship between the stenosis of clinically relevant artery or the characteristics of carotid plaques and frequent transient ischemic attacks(TIA).Methods Seventy-nine consecutive patients sufiered TIA attribute to carotid territory in the acute phase(within 7 days )who had been admitted to neurology department of Xuanwu Hospital from August 2005 to January 2007 were retrospectively analyzed.Patients with nonatherosclerotic vasculal disease were excluded.According to the times of TIA from the first attack to the day of hospitaliztion(within 7 days)patients were divided into two groups:those who had sparse TIA(onsets＜3 times),and those who had multiple TIA(onsets≥3 times).All patients underwent the examination of DSA.carotid ultrasound and transcranial doppler.The degree of stenosis of clinically relevant artery and the characteristics of carotid plaques were compared between the two groups.According to degree of stenosis of relevant artery,we defined as normal or＜50%stenosis.50%-69%stenosis.70%-99%stenosis or occlusion.According to the characteristics of carotid plaques we divided into stable or unstable plaques.Resuits Patients with TIA in carotid territory had more intracranial artery diseases.The middle cerebral artery was the most commonly involved artery(5 1.2%).the extracranial internal carotid artery was the next(37.2%).Multiple TIA were more likely to have a short duration of symptoms≤10 min than sparse TIA(x2=5.343,P=0.021).A significant stenosis of clinically relevant artery(≥50%)was demonstrated more frequently in the multiple TIA group(66.7%)than in the sparse TIA group(35.3%,x2=7.655,P=0.006).No significant correlation was observed between the multiple TIA and characteristics of carotid plaques in the focus side(x2=0.939,P=0.332).Conclusions Frequent TIA is significantly associated with a short duration of symptoms and≥50% stenosis of clinically relevant artery.Transient flow reduction by hemodynamic compromise may he an important mechanism of frequent TIA.