A method using dry ashing combined with triple-phase ion-exchange chromatography was developed to enrich chlorine in the plant, which could eliminate the effect of organic impurities on the determination of chlorine isotope by thermal ionization mass spectrometry. In the procedure, the recoveries indicated that there was no loss of chlorine and no fractionation of chlorine isotopes occur. The results showed that the composition of chlorine isotope in the tissues of plants in Qinghai-Tibet Plateau area and Shandong area ranged from-1 . 79‰ to ﹢4 . 77‰ with an average of 1 . 20‰. δ37Cl values of the two plant samples in Shandong area not more than 0‰indicated that 35 Cl was enriched in the organs of the two plants andδ37Cl values in Qinghai-Tibet Plateau area more than 0‰ indicated the deficiency of 35 Cl. Chlorine isotope composition fractionated significantly in the plant samples or in different tissues of a plant. This may be caused by the differences of the medium where the plants grow, the transport of chlorine or the physiological effect in the uptake of chlorine by plants , which put forward a new insight for the further investigation of chlorine behavior in plant and the global cycling of chlorine in the biogeochemistry.

BACKGROUND: Application of traditional osteoarthritis animal models was limited by long duplicated time, poor stability, different successful rate, and rough analysis of osteoarthritis.OBJECTIVE: To observe clinical and pathological features of osteoarthritis by modified Hulth modeling way and to determine the stages of ostecarthritis.METHODS: A 2-cm medial longitudinal incision was resected to expose knee joint. Anterior and posterior cruciate ligament and medial collateral ligament were cut off, and medial meniscus was fully cut to reserve articular cartilage., The injured limb was not fixed postoperatively. Animals were allowed to move freely. At one week after surgery, 800 000 U penicillin was used to avoid from infection, 30 mind, twice per day, for 12 successive weeks. The normal group was treated without any treatments. Pathological features were observed using Mankin scores under electron and optic microscope at 4, 6, 8, 10, and 12 weeks postoperatively.RESULTS AND CONCLUSION: Changes of osteoarthritis were observed in the model group at 4 and 6 weeks after operation,showing synovial hyperemia and hyperplasia, increased synovial fluid effusion, cartilage surface roughness, matrix stained tinge,and Mankin score of 3.5-3.8. Intermediate stage changes of osteoarthdUs were found in the model group at 8 weeks after operation, showing synovial hyperplasia, less synovial fluid, flssuration reaching cartilage surface, cartilage cells with tangled and uneven staining matrix, Mankins score of 8-9. Advanced osteoarthritis changes were observed in the model group at 12 weeks after operation, showing severe nodular synovial hyperplasia, less and turbid synovial fluid, osteophyte formation of serious exposure of subchondral bone, cartilage calls reducing the majority of loss of matrix staining, and Mankin score of 12-14. Electron microscopy indicated a coincidence with the histological observation of cell mutation. The rabbit model by Hulth suggested that early change of osteoarthritis occurred at 6 weeks after operation, intermediate stage at 8 weeks, and advanced stage at 12 weeks.This model could be more comprehensive response to osteoarthdtis cartilage degeneration from early compensatory hypertrophy to decompensation after the cartilage cells and matrix reduction, cartilage softened to endarterectomy missing characterized the late changes in the entire process.

Aim To investigate the effect of intrathecal injection of fluorocitrate(Fc)on mechanical and thermal hyperalgesia induced by complete Freund's adjuvant(CFA)injection in rats.Methods The mechanical withdrawal threshold(MWT)and thermal withdrawal latency(TWL)were measured before and after CFA or Fc treatment.The changes of glial fibrillary acidic protein(GFAP)and OX-42(a microglial marker)expression in the spinal cord dorsal horn were evaluated by immunohistochemistry analysis.Results Rats with CFA-induced arthritis showed mechanical allodynia and thermal hyperalgesia,which was correlated with the increased GFAP and OX-42 expression in the spinal cord dorsal horn.Intrathecal injection of Fc markedly suppressed CFA-induced thermal hyperalgesia and mechanical allodynia.Fc significantly attenuated the activation of GFAP and OX-42 in the spinal cord dorsal horn.Conclusions The glia activation in spinal cord is closely related to the progress of CFA-induced peripheral hyperalgesia.Fc may exert antihyperalgesic effect by inhibiting the activation of astrocyte and microglia.

BACKGROUND:Clinical work shows that there are a large proportion of patients suffering from osteoerthritis(OA)and osteoporosis(OP),therefore establishing OA+OP models to simulate the clinical disease in postmenopausal women addreasing the basic characteristics of lesions,will offer better prevention and treatment of OA+OP in clinical practice.OBJECTIVE:To attempt to create OA+OP animal model.DESlGN,TIME AND SETTING:Randomized controlled animal expedment in terms of call pathology was perforrned between August 2008 and January 2009 in the Scientific Research Center and Traditional Chinese MediciRe Hospital of Xinjiang Medical University.MATERIALS:Forty 4-month-old female SD rats,weighing(210±10)g,were randomly divided into normal control group,OA group,OP group,OA+OP group.METHODS:In the OA+OP group,rats underwent abdominal incision 1.5 cm longitudinal on both sides of lumbar spine on back,followed by bilateral ovarian resection and ovarian artery ligation,to establish OP models.One month after the skin incision,left knee skin,subcutaneous tissue and fascia were cut,then joint capsule was given a vertical incision.Anterior cruciata ligament was cut off in orthophoria,meniscus was removed,followed by subcutaneous tissue and skin suture,OA model was prepared and placed under warm environment.antibiotic subcutaneous injection for 3 days,and the displacement of one month.OA group and OP group were produced in accordance with the above method of OA.OP model.Normal control rats received no treatment.MAIN OUTCOME MEASURES:When the rats were 6 months old,the left knee femoral condyle articular cartilage were examined by light microscopy and electron microscopy,left femur was used to measure proximal femoral bone mineral density.RESULTS:In three groups of model rats,articular cartilage become thinning and degeneration.In the OP model group and OA+OP model group,trabecular was sparse and arranged in disorder.In the OA model group and OA+OP model group,the incision layer was chiefly deleted,transferring layer was greatly injured,call hypertrophy and colony were observed,a large amount of blood capillary invaded into cartilage and calcification layer,even break through tidal line;in OP model group,incision layer of articular cartilage became thinning and appeared bilateral tidal line.In the OA model group and OA+OP model group,knee condylar number of special-shaped cartilage cells increased,manifested as irregular nuclei,reduced cell organelle,nuclear shnnkage,chromatin uneven distdbution,mitochondrial swelling,rough expansion of endoplasmic raticutum,accumutation of cytoplasmic microfilaments,showing lipid droplets and glycogen granules,gliel fibdllary fracture,disorder arrangement,a large number of cartilage calls were apoptotic.Three groups of model rats exhibited a dramatically decreased bone mineral density compared with control rats(P＜0.05).CONCLUSION:The animal modal of OA+OP was successfully established.

Objective To investigate the effect of propentofylline on nerve growth factor (NGF) and IL-1βrelease from rat cerebral cortical astrocytes. Methods Primary cultured rat astrocytes from SD rats (1-3 d,weighing 6-8 g) after 4 passages were randomly divided into 8 groups ( n = 6 wells each): group Ⅰ control (group C); group Ⅱ , Ⅲ, Ⅳ the astrocytes were exposed to propentofylline 10, 100 and 1000 μmol/L respectively (group P1, P2, P3 ); group Ⅴ the astrocytes were exposed to LPS 1 μg/ml and group Ⅵ, Ⅶ, Ⅷ the astrocytes were exposed to propentofylline 10, 100 and 1000 μmol/L in addition to LPS 1 μg/ml (group P1 + LPS, P2 + LPS,P3 + LPS). The astrocytes were then incubated for 3 days in all 8 groups. The concentrations of IL-1β and NGF in the supernatant were detected at 1 and 3 days of incubation using ELISA. Results LPS activated astrocytes resulting in decrease in NGF release and increase in IL-1β release. Propentofylline significantly increased NGF release and decreased IL-1β release from astrocytes incubated alone or with LPS by suppressing activation of astrocytes. Conclusion Propentofylline can enhance NGF release and inhibit IL-1β release from rat cerebral cortical astrocytes.

Objective To evaluate the role of gliocytes in the spinal cord in the development of inflammatory pain (IP) in rats. Methods Adult male SD rats weighing 180-220 g were used in this experiment. A catheter was implanted in the subarachnoid space according to the method described by Yang. Animals with abnormal motor function of the hindlimb after intrathecal (IT) catheter implantation were excluded. IP was induced by subcutaneous (sc) injection of complete Freund's adjuvant (CFA) 50 μl at the lateral side of the ankle joint of the right hindpaw. Sixty-five rats were randomly divided into 5 groups ( n = 13 each): group I IP control normal saline (NS) 50μl was injected sc instead of CFA; group II IP; group IE PC (IT) + IP control fluorinated citric acid (FC, a gliocyte metabolism inhibitor) 1 nmol/10μl was injected IT at 15 min before NS 50 μl sc injection; group IV NS (IT) + IP and group V FC (IT) + IP. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured 2 d before induction of IP (T_0, baseline) .before and at 2, 4, 6, 8, 10, 12, 24 and 26 h (T_(1-9)) after sc NS or CFA injection. Five enimals in each group were killed at T_5 (8 h after sc NS/CFA injection) and the lumbar segment (L_(4,5)) was removed for determination of glial fibrillary acidic protein ( CFAP) and OX-42 expression by immuno-histochemistry. Results In group Ⅱ and Ⅳ sc CFA significantly decreased MWT and TWL. Mechanical and thermal hyperalgegia induced by sc CFA was significantly suppressed by intrathecal FC in group V . IP significantly increased GFAP and OX-42 expression in the spinal cord. Intrathecal FC significantly attenuated IP-induced up-regulation of GFAP and OX-42 expression in the spinal cord. Conclusion The activation of gliocytes in the spinal cord is involved in the development of CFA-induced hyperalgesia in rats.

Pancreatic ductal adenocarcinoma (PDAC) is among the most devastating human malignancies. The poor clinical outcome in PDAC is partly attributed to a growth-permissive tumor microenvironment. In the PDAC microenvironment, the stroma is characterized by the development of extensive fibrosis, with stromal components outnumbering pancreatic cancer cells. Each of the components within the stroma has a distinct role in conferring chemoresistance to PDAC, and intrinsic chemoresistance has further worsened this pessimistic prognosis. The nucleoside analog gemcitabine (GEM) is usually the recommended first-line chemotherapeutic agent for PDAC patients and is given alone or in combination with other agents. The mechanisms of intrinsic resistance to GEM are an active area of ongoing research. This review highlights the important role the complex structure of stroma in PDAC plays in the intrinsic resistance to GEM and discusses whether antistroma therapy improves the efficacy of GEM. The addition of antistroma therapy combined with GEM is expected to be a novel therapeutic strategy with significant survival benefits for PDAC patients.

Objective To explore the clinical significance and mechanisms of chromatin licensing and DNA repli-cation factor 1(CDT1)in lung adenocarcinoma).Methods The gene expression samples of lung adenocarcinoma tissue and normal lung tissue were downloaded from the TCGA database,and perform differential analysis,GO a-nalysis,independent prognosis analysis,and correlation analysis with immunotherapy using R language.CDT1 ex-pression in lung adenocarcinoma and normal tissues was detected by PCR in clinical samples.The changes of cell proliferation and cycle in si-CDT1 knockdown group and si-NC control group were detected by flow cytometry.The invasive ability of each group was detected by Transwell.The expressions of CDT1,TPX2 and p53 in each group were detected by Western blot.Results The TCGA data analysis revealed CDT1 as a differentially expressed gene.GO analysis indicated that CDT1 was closely associated with the cell cycle.The high expression of CDT1 in lung adenocarcinoma tissues was validated in clinical samples.CDT1 could serve as an independent factor for predicting the prognosis of lung adenocarcinoma and had predictive value for immunotherapy in lung adenocarcinoma.Knock-down of CDT1 resulted in a significant decrease in cell proliferation ability compared to the control group,and cells were noticeably arrested in the G1 phase.Transwell assay results demonstrated a significant reduction in invasive capacity in the CDT1 knockdown group.Knockdown of CDT1 led to a significant decrease in TPX2 expression and a significant increase in p53 expression,while overexpression of CDT1 yielded the opposite effect.Conclusion Re-sults demonstrate the elevated expression of CDT1 in lung adenocarcinoma,its association with prognostic signifi-cance,and its impact on lung adenocarcinoma's occurrence and development by influencing TPX2 and p53.