AIM: To investigate the effect of L-phenyla lanine on vascular remodeling in hypertensive rats. METHODS: Vascular remodeling was measured by laser scanning conf ocal microscopy (LSCM) in mesenteric resistance arteries isolated from spontaneo usly hypertensive rat (SHR) and normotensive Wistar-Kyoto (WKY) rat. The effect of L-phenylalanine on the hypertensive vascular remodeling was observed. The thi rd most distal first-order branches of mesenteric resistance arteries from SHR a nd WKY were studied. The arteries were fixed under pressure. The segments were s tained with the nuclear dye propidium iodide. The diameter, wall thickness and o rientation angle of smooth muscle cells were measured with LSCM. RESULTS: Compared with WKY, SHR arteries showed: (1) smaller lum en, (2) increased wall thickness, (3) disorganized orientation angle of smooth m uscle cells. L-phenylalanine treatment induced specific changes in the lumen, wa ll thickness and the orientation angle of smooth muscle cells. CONCLUSIONS: Hypertension induces vascular remodeling of the bra nches of mesenteric arteries from SHR. L-phenylalanine inhibits the vascular rem odeling process of hypertension.

Objective To analyze the characteristics ot lymph node metastasis and prognostic factors for carcinoma of papilla of Vater (CPV) after pancreaticoduodenectomy (PD).Methods From January 2005 to December 2010,94 patients with CPV underwent PD and dissection of regional lymph nodes at the Eastern Hepatobiliary Surgery Hospital.We carefully evaluated nodal involvement in the patients to determine the lymphatic spread of CPV and analyzed the clinicopathological variables in relation to prognosis.Results The overall rate of nodal involvement was 46.8％.Using the UICC staging (7th edition),lymphatic invasion in pT1,pT2,pT3 and pT4 were 15.4％ (2/13),62.7％ (32/51),80.0％ (8/10) and 100％ (2/2),respectively.The metastatic rates in the posterior pancreaticoduodenal lymph nodes,the mesopancreatic lymph nodes,the hepatoduodenal ligamental lymph nodes and the proper hepatic periarterial lymph nodes were 30.9％ (29/94),21.3％ (20/94),11.7％(11/94) and 6.4％ (6/94),respectively.Significant prognostic factors were tumor pT stage (P＜0.01),duodenal wall infiltration (P =0.001),liver metastasis (P =0.001),pancreatic paren chymal invasion (P=0.004),nodal involvement (P＜0.01) and different regional lymph nodes invasion (the posterior pancreaticoduodenal,P＜0.01; the mesopancreatic,P＜0.01; the hepatoduodenal ligamental,P＜0.01; the proper hepatic periarterial,P=0.010).Cox regression analysis for overall survival revealed that the posterior pancreaticoduodenal nodal involvement (P＜0.01),the mesopancreatic nodal involvement (P＜0.01) and duodenal wall infiltration (P=0.019) were significant independent prognostic risk factors.Conclusions The mesopancreatic lymph nodes and the posterior pancreaticoduodenal lymph nodes should equally be regarded as the first stop in lymphatic spread of CPV.Therefore,we should pay much attention to these regional lymph node dissections,especially to ensure complete resection of the uncinate process and the mesopancreas.

Objective To assess clinical curative effect of three types of combined posterior atlantoaxial internal fixation techniques in treatment of atlantoaxial instability. Methods The study involved 68 patients with atlantoaxial instability treated with different fixation techniques from August 2002 to March 2008. ( 1 ) Transpedicular fixation was performed in 32 patients including 20 patients with Anderson Ⅱ odontoid fractures (seven with old odontoid fracture and 13 with fresh fractures), six with type Anderson Ⅲ fresh odontoid fractures, four with disrupt of transverse ligament of the atlas and two with congenital loose odontoid process combined with atlantoaxial instability. (2) Transpedicular internal fixation with screws of atlas incorporating C2 laminar screws was performed in 20 patients with upper cervical injury including eight with type Ⅱ odontoid process fractures combined with atlantoaxial backward dislocation,four with type Ⅱ odontoid process fractures combined with atlantoaxial forward dislocation, two with nonunion of odontoid process fractures, three with type Ⅲ odontoid process fractures combined with atlantoaxial unsteadiness and three with atlantoaxial dislocation combined with disrupt of transverse ligament of atlas. (3)A total of 16 patients with traumatic atlantoaxial instability, reducible atlantoaxial dislocation and irreducible atlantoaxial dislocation were treated with four-point internal fixation technique using autologous iliac bone grafts. Results (1) A total of 120 screws were implanted in 32 patients, with no spinal cord or vertebral artery injury after surgery. Atlas lateral mass fixation was adopted in three patients because of broken posterior arch of the atlas. Postoperative CT showed that two screws were inserted into the vertebral artery hole and that one screw was inserted medially into the spinal canal and caused medial correx rupture, but both with no clinical symptoms. All 32 patients were followed up for 6-42 months ( average 26 months), which showed solid fusion in all patients. The postoperative JOA scores ranged from 13.2 points to 16.8 points (average 14. 8 points). (2) Thirty-two screws were implanted in 20 patients,with no spinal cord or vertebral artery injury. The patients were followed up for mean six months ( range 6-14 months). Postoperative X-ray showed sound bone fusion, with no cervical instability, loosening or breakage of the screws. (3) The symptoms of all the patients were improved at different degrees, with no neurological deterioration or severe complications, such as nerve blood vessel injury. All 16 patients were followed up for 8-26 months ( average 16 months), which showed bony fusion in all patients at 3-6 months after surgery. The spinal cord function was improved markedly in five patients, good in eight, mild in two but unchanged in one. Conclusions Three types of combined posterior atlantoaxial internal fixation techniques have advantages of rigid, short-segmental and three-dimensional fixation and hence are effective methods for treatment of upper cervical injuries. The combination mode can be varied according to specific condition of the patients.

Objective:To explore the expression of aquaporin1 (AQP1) in human glioma tissues and its relationship with the clini-copathological parameters and prognosis of this tumor. This study also observed the function of AQP1 in the proliferation and invasion of LN229 glioblastoma cells. Methods:The expression of AQP1 in 135 cases of glioma was detected by immunohistochemical meth-od, and the correlation between AQP1 and pathological features of glioma was analyzed. The relationship of AQP1 with survival was al-so investigated using 103 specimens with complete clinical data. AQP1 was successfully transfected into LN229 cells with lentiviral vector, and the expression of AQP1 protein was tested by Western blot. Cell proliferation was detected by using methyl thiazolyl tetrazo-lium assay, whereas cell invasion was determined by Transwell assay. Results:The expression of AQP1 was positively correlated with pathological grading. High AQP1 expression was associated with poor prognosis (P<0.05). Moreover, the overexpression of AQP1 can significantly increase the proliferation and invasion of LN229 cells (P<0.05). Conclusion:AQP1 is closely associated with the progres-sion of glioma. Upregulation of the AQP1 expression promoted the proliferation and metastasis of glioma cells. These findings indicat-ed that AQP1 can function as a therapeutic target for glioma in future research.

Objective:To investigate the functions of the ITSN1-S SH3 domains in U87 glioblastoma cell proliferation and to de-termine the underlying molecular mechanism. Methods: A recombinant lentiviral vector with an mGFP label was constructed. EH1-EH2, EH1-EH2-CC, and ITSN1-S genes were amplified using polymerase chain reaction and then cloned into recombinant lenti-viral vectors. The four lentiviral plasmids were packaged using HEK 293T cells and subsequently used to infect U87 cells. Stable cells were screened using puromycin and separately labeled as vector/U87, EH1-EH2/U87, EH1-EH2-CC/U87, and ITSN1-S/U87. Western blotting was used to detect the expression of each protein. Proliferation and soft agar assays were performed to detect cell proliferation. Results:In the proliferation and soft agar assays, the proliferation capacity of the ITSN1-S/U87 cells was clearly enhanced compared with those of the vector/U87, EH1-EH2/U87, and EH1-EH2-CC/U87 cells (P<0.05). Moreover, the proliferation capacity of the latter three groups showed no observable difference (P>0.05). On the 6th day, the vector/U87, EH1-EH2/U87, EH1-EH2-CC/U87, and ITSN1-S/U87 cell numbers were (29.16 ± 1.19) × 104, (22.82 ± 0.94) × 104, (22.17 ± 0.90) × 104, and (21.93 ± 1.15) × 104, respectively. On the 21st day, the number of colony formation in vector/U87, EH1-EH2/U87, EH1-EH2-CC/U87, and ITSN1-S/U87 was (6.37±0.41)×103, (2.65±0.34)×103, (2.23±0.31)×103, and (2.1±0.29)×103, respectively . Conclusion:ITSN1-S overexpression significantly promotes U87 cell proliferation. Specifically, the SH3 domains possibly serve vital functions in glioma cell proliferation.

Objective To investigate the stress characteristics of atlanto-axial bony structure under conditions of anteflexion,posterior extension,lateral flexion,and rotation after artificial atlanto-odontoid joint arthroplasty using three-dimensional finite element method and to improve the orientation of artificial atlantoodontoid joint from perspective of stress.Methods A three-dimensional finite element model of prosthetic atlanto-odontoid joint arthroplasty was created from CT images of the artificial atlantoodontoid joint and cervical vertebrae using software Mimics,Freeform,and Ansys.Stress characteristics of the model dealt with proneness,posterior extension,lateral flexion,or rotation loads were observed.Biomechanical performance of the bony structure of the model was analyzed and the orientation in improving the prosthesis was discussed.Results Anteflexion loading produced a maximum stress of 0.138 ×l08 N/m2 at the junction of lateral mass and posterior arch of the atlas,and 0.201 × 108 N/m2 at axial nail hole,contact point of plates with the axis,and posterior arch of the axis.Posterior extension loading produced a maximum stress of 0.666 × 107 N/m2 at junction of lateral mass and posterior arch of the atlas and 0.254 × 108 N/m2 at arch of the axis.Besides,stress concentration occurred at atlantoaxis nail hole.Right bending produced a maximum stress of 0.124 × 108 N/m2 at nail hole of right mass of atlas and 0.178 × 108 N/m2 at right contact point of the axis with plates.Right rotation produced a maximum stress of 0.847 × 107 N/m2 at junction of lateral mass and posterior arch of the atlas and 0.170 × 109 N/m2 at contact point of the axis with plates.The finite element model comprised 28 620 nodes and 107 441 units and provided good defining of the structural properties of artificial atlanto-odontoid joint arthroplasty.Under different loading conditions,the stress was mainly distributed in contact point of the vertebral body with plates,nail holes,junction of lateral mass and posterior arch of the atlas,and axial pedicle.Conclusions Prosthetic atlanto-odontoid joint scatters a part of the stress and alters the stress distribution of the atlas and axis from the intact condition.Finite element method can obtain complete analysis of the stress distribution of the artificial atlanto-odontoid joint arthroplasty.

Aquaporin 1 (AQP1) is a specific protein that transports water molecules through the cell membrane. AQP1 mainly ex-presses in the choroid plexus epithelial cells of the central nervous system and participates in the formation of cerebrospinal fluid. In gli-omas, AQP1 expresses in neoplastic astrocytes and vascular endothelial cells. AQP1 expression is increased in parallel with histological grade in gliomas. AQP1 expression in gliosarcoma cell line is induced by dexamethasone, platelet-derived growth factor, sodium chlo-ride, hypoxia, D-glucose, and fructose. AQP1 mRNA expression is upregulated with increasing dosage. Through the expression of AQP1 in gliomas and the existing research on its function, we suggest that AQP1 may participate in tumor angiogenesis and tumor-relat-ed edema. AQP1 is closely associated with glioma cell migration. The function of AQP1 and its mechanism has been elucidated. Thus, this protein can be used as a new therapeutic target to inhibit the metastasis and recurrence of gliomas.

Objective To evaluate the clinical effect and safety of the occiput-cervicle or C1-C2 internal fixation and bone graft fusion in treatment of the unstable atlas fracture.Methods A retrospective study was performed in 38 patients with unstable atlas fractures treated by the occiput-cervicle or C1-C2 internal fixation and bone graft fusion from October 2004 to March 2009.Six patients with comminuted atlas fracture combined with instability of the occipito-atlantoid articulations were treated with occiput-C2 fusion(five patients)and with occiput-C3 fusion(one patient).There were seven patients with typical Jefferson fractures,three with semiring fractures,eight with atlas fractures combined with Anderson type Ⅱ odontoid process fractures,three with atlas fractures combined with Hangman's fractures (two patients with Levine and Edwards type Ⅲ Hangman's fractures were treated with occiput-C3 fusion and one patient Levine and Edwards type Ⅱ Hangman's fracture was treated with C1-C2 fusion),three with atlas fracture combined with lower cervicle injury,six with rupture of transverse ligament combined with instability of atlanto-axial joint(Dickman transverse ligament type Ⅰ injury)and two with comminuted fracture of the lateral mass associated with bony avulsion of the medial tubercle and transverse ligament(Dickman transverse ligament type Ⅱ injury).Of all,five patients were treated with occiput-C2 fusion,three treated with occiput-C3 fusion and 30 treated with C1-C2 fusion.Results All the patients were followed up for a range of 12-46 months(average 28 months),which showed improvement of clinical symptoms in some extent postoperatively.The operation time ranged from 80 to 190 min ates(average 135 minates),with intraoperative blood loss for 200-3 300 ml(average 460 ml)and average fluoroscopic time for 60 seconds.There were no neurological deficits,vertebral artery related complications or other complications in all the patients during the surgical operation.No neurological deficit was aggravated after the patient's mobilization with brace three days after operation.The enous plexus of blood vessel at C1-C2 rupture induced by the use of electrocautery was found in three patients who showed no cerebral hemodynamic deficit after hemostasis with hemostatic sponge and cotton piece.The follow-up X-ray and CT manifested osseous fusion in all the patients,with no looseness or breakage of the screws.The late follow-up showed pain associated with movement and limited range of motion in four patients(11%)and occipital neuralgia in one.Conclusions An occiput-cervicle fixation fusion or a C1-C2 fixation fusion combined with short external fixation can reestablish the upper cervical stability and prevent further injury of the spinal cord and nerve function and hence is an ideal option for C1 burst fracture with or without rupture of the transverse ligament.

Objective To investigate the current status of treatment on traumatic ruptured spleen in a regional medical center in Tianjin,China.Method Logistic analysis of 16 impact ffactors of treatment decision on 147 patients with traumatic ruptured spleen.Results The type of trauma,pulse rate at admission,result of abdominal puncture and CT grade were related to treatment decision making.Splenectomy was carried out in 89 patients (60.54％) which accounted for 89.90％ of all surgical procedures.Splenectomy was carried out in 50.85％ of patients with CT grade 1 or 2 (or 85.71％ of grade 1 and 2 surgery),and 100％ of CT grade 3 or 4.Spleen preservation surgery was carried out in 7 patients with CT grade 1 or 2.Conclusion Splenectomy was carried out in most cases in this study.It is necessary to investigate the treatment of splenic trauma in regional medical centers,and to develop more reliable surgical techniques to carry out more spleen-preservation surgery ffor CT grade 1 or 2 ruptured spleen.

Objective To investigate the optimal trajectory of posterior occipital condyle screw fixation via radiological and anatomical study.Methods Twelve adult craniocervical junction complete specimens were selected.The length,width and height of occipital condyle and the inclination angle of the longest axis were measured by CT scanning and reconstruction.Subsequently,occipital condyle screws were inserted with reference to CT measurements.After screw fixation,accuracy and safety of the placement of occipital condyle screw were verified by gross observation and CT scanning.Results Preoperative measurements of height and width of the occipital condyles indicated the placement of 4.0 mm bicortical screws was secure.Left vertebral artery horizontal sections of 2 specimens were slightly pressed without damage.CT scanning identified no damage to the inner or outer wall of the occipital condyle and the hypoglossal canal.Trajectory parameters between the right and left sides were slightly different,but no significant difference was observed (P ＞ 0.05).Average screw channel length and inclination angle were (20.8 ±2.6)mm and (37.1 ± 4.7)°respectively.Angle between screw and skull base tangent was observed as (8.5 ± 1.7) °.Distance between screw axis and hypoglossal canal was observed as (3.1 ± 1.1) mm.And the distance averaged (4.6 ± 1.4) mm between occipital condyle screw entry point and skull base and (6.1 ± 1.5) mm between entry point and inside edge of the occipital condyle.Conclusion Occipital condyle can be used as a new alternative fixed point in occipitocervical fusion.