MicroRNAs (miRNAs) are a class of highly conserved small non-coding RNA molecules.They negatively regulate gene expression at the post-transcriptional level,which may lead either to translational repression or mRNA degradation.MiRNAs are highly conserved in evolution and extensively involve in organism growth,development,apoptosis,and other pathological or physiological processes.Recent studies have shown that the specific miRNAs play important roles in the process of the occurrence and development of ischemic cerebrovascular disease.At the same time,they participate in the regulation of injury mechanism as well as protection and repair mechanisms after cerebral ischemia.Fully understanding the regulatory effect of functional significance of the miRNAs and their changes of expression levels not only help identify therapeutic targets,prevent neuronal death,and reduce ischemic brain damage,but also help clear apoptotic cells,promote angiogenesis and neurogenesis by regulating their expression levels.In addition,miRNAs may also provide a new strategy for the preservation and diagnosis of ischemic stroke.

Objective To observe the effect of leptin on proliferation and apoptosis of breast cancer MCF-7 cell line,and to explore the effect of leptin on occurrence and development of breast cancer.Method The MCF-7 cell line was treated with different concentration of leptin in vitro.Cell proliferation was evaluated by MTT assay. Distribution of cell cycle was determined by flow cytomery, meanwhile the rates of apoptosis were estimated on the basis of Annexin V-FITC/PI apoptosis detection. Results When treated with different concentration of leptin for 24 h, 48 h and 72 h, they could significantly induce the proliferation of MCF-7 cells by MTT method.There was not interaction between concentration of leptin and time course (F=0.919,P=0.523).The main effect of concentration of leptin and time course was statistically significant (F=12.699,P=0.000;F=647.881, P=0.000). Compared 200 ng/ml and 400 ng/ml with the control group, we found the difference was statistically significant by multiple comparison (P=0.007,P=0.000,respectively).The difference was also statistically significant among time course by multiple comparison (P=0.000,respectively).By the flow cytometry analysis,it was found that the 100 ng/ml and 400 ng/ml leptin groups could change the distribution of cell cycle of MCF-7 cell line after 48 h. Compared with control group, the cell number decreased by 14.42 ％ in G0/G1 phase (F=10.464, P=0.044),but increased by 7.57 ％ and 22.19 ％ respectively in S phase (F=47.361,P=0.005).The difference was not statistically significant in G2/M phase (F=1.77, P=0.311).However, the effect of apoptosis inhibition was not obvious. Conclusions Leptin could stimulate the proliferation of MCF-7 cell line and change the distribution of cell cycle.But leptin could not inhibit apoptosis of MCF-7 cell line.It suggested that leptin may serve as a risk factor of breast cancer development.

ObjectiveTo study the role of the myenteric plexus (ENS) nitrergic neurons in type 2 diabetic rats with gastroparesis.MethodsThiry male 8-week-SD rats were randomly divided into control group (CON),type 2 diabetic group (DM),insulin-treated group ( INS ) and insulin-lipoie acid group( LA ),each 15.The rats were sacrificed at 16 weeks after diabetic model established,the stomach relative residual rate of pigmented was measured and the protein content of neuronal nitric oxide synthase (nNOS) was evaluate,the level of malondialdehyde (MDA) and superoxide dismutase (SOD),were measured,the the morphological changes of gastric antrum nitrergic neurons was observed.ResultsCompared with CON group,gastric motility,gastric antrum nitrergic neuron count,T-SOD and CuZn-SOD,and were significantly decreased in DM group ( P ＜0.05).Compared with the CON group,DM group gastric antrum nitrergic neurons nNOS expression decreased,while MDA levels significantly increased ( P ＜ 0.05 ).Compared with DM group,INS group and LA group has significantly rapider gastric motility than that of DM group ( P＜ 0.05 ),the neuron counting markly increased in nitrergic neuron of gastic sinus ( P ＜ 0.05 ),increased expressions of nNOS in gastric sinus,while still lower than control group( P ＜0.05).compared with the INS group,antrum nitrergic neuron counts of LA group significantly increased ( P ＜ 0.05 ).Conclusion The gastrointestinal dyskinesis of type 2 diabetic rats might be associated with lesions of gastric myenteric plexus nitrergic neuron.Insulin intensive therapy and treated with alpha-lipoic acid as an antioxidant can inhibit the abnormally high levels of oxidative stress,protect gastrointestinal nitrergic neurons,delay the progress of diabetic gastrointestinal motility disorders.Insulin combined with a-lipoic acid treatment is superior to single-use insulin.

Objective To summarize and analyze data of solid pseudopapillary tumor of pancreas (SPTP) in China,and investigate its epidemiology,clinical features,diagnosis and treatment.Methods Retrieval of Chinese Medical Current Contents and China Biology Medicine disc by the key words of solid pseudopapillary tumor of the pancreas,papillary cystic tumor of the pancreas,pancreatic papillary epithelial tumor,cystic solid tumor of pancreas and Frantz tumor were performed,and relevant literatures were included.Results A total of 1180 SPTP patients from 117 articles were involved.There were 1054 women and 126 men and the ratio of male to female was 1:8.37.The average age was 29 years old (range 9 ～83 years).Detailed clinical information was available for 1172 cases,and the main clinical manifestations included abdominal discomfort (n=526,44.88％),medical check-up (n=464,39.59％),abdominal mass (n=131,11.18％).Laboratory and imaging tests were non-specific.The tumors size was 1.3～ 30 cm with a mean value of 7.84 cm.Four handreds and seven (36.8％) cases were located in pancreatic head,96 (8.7％)were in pancreas neck and 587 (53.1％) were in the body and tail of pancreas.Eleven handreds and sixteen patients received treatment,and the resection rate was 99.2％ (n =1107).Pathological examination showed that 628(57.0％) cases were benign and 306 (27.8％) were presented as malignant behavior,mainly as infiltrative growth and invasion of the surrounding organs,vessels.Nine handreds and seventy-seven cases were followed up (ranging from 1 month to 13 years),and re-occurrence or metastasis were detected in 42 cases (4.3％) and 24 patients died.Conclusions Solid pseudopapillary tumor of pancreas is a rare pancreatic tumor with low-grade malignant potential,and part of this tumor may present as malignant behavior and it primarily affects young females.No characteristics in clinical manifestations,laboratory and imaging tests are found.Pathological examination can confirm the diagnosis.Surgical resection is the therapy of choice and the prognosis is good.

BACKGROUND: Percutaneous laser disc decompression(PLDD) is a new technology developed to treat lumbar herniated disk inrecent years; however,only limited literature has been reported about cohort study on its indications.OBJECTIVE: To treat patients with lumbar disc herniations by PLDD and evaluate the effects of PLDD in releasing painandimproving lumbar function after operation.DESIGN: Non-randomized concurrent controlled trial based on thepatients.SETTING: Department of Radiology of the 474 Hospital of Chinese PLA.PTICIPANTS: This study recruited totally 173 patients ( 101 males and 72 females aged from 18 to 75 years) who received PLDD in the Department of Radiology of the 474 Hospital of Chinese PLA from July 1998 to August 2002 and were followed up for over one year.METHODS:The 173 patients were divided into good indication group (Group A, n = 139) and poor indication group(Group B, n =34). Group B was further divided into extrusion group(Group B1 of 8 patients),lumbar canal stenosis group(Group B2 of 15 patients) and other conditions group (Group B3 of 11 patients). VAS scoring criteria and modified Macnab criteria were used to evaluate the curative effects.MAIN OUTCOME MEASURES: Primary results: the degree of pain and lumbar function. Secondary results:the success rate of puncture as well as adverse events and side effects.RESULTS: The success rate of puncture was 96. 3％ for performing through L5 - S1 and 100％ through L3-4 and L4-5. In Group A, excellent postoperative effects were seen in 63 cases, good in 51 cases, fair in 20 cases and poor in 5 cases, with 82.0％ excellent and good rates. The excellent and good rate in Group B was 55.9％. Postoperative back pain could be relieved several days later. Other complications such as disc infection,psoas hematoma,rupture of colon,injuries of nerve roots and bloodvessels did not occur. There was a significant difference between Group A and Group B(x2=10.38, P ＜0.05).CONCLUSION: (① PLDD is a convenient, safe and reliable procedure in treating lumbar disc herniation because of its high success rate, satisfactory results and fewer complications.② Proper selection of indications helps improve the curative effects of lumbar disc herniation.

Purpose To establish a HPLC method for determination of the content of trifluoroacetic acid in bivalirudin.Methods Kromasil 100-5 C_(18) column(4.6 mm×200 mm,5 μm)and 0.07% phosphoric acid solution(pH 3.0)-methanol(98:2)as the mobile phase at a flow rate of 1.0 mL/min were used with a column temperature of 30 ℃,a detection wavelength of 210 nm and a injection volume of 20 μL.Results The standard curve of trifluomacetic acid was linear in the range of 198.4-992.0 μg/mL,r=0.999 9.The detection limit Was 40 ng.The average recovery rate of method was 99.9%,and RSD was 0.41%.Conclusion The method of content determination was practicable and accurate.It can be used for content determination of trifluoroacetic acid in bivalirudin.

Objective To investigate the effect of microbubble-enhanced non-focused ultrasound on liver uhrastructure during the treatment of hepatic trauma.Methods The model of hepatic trauma was established in 18 healthy New Zealand rabbits.The subjects were divided into trauma group,ultrasound group and ultrasound-microbubble group according to the random number table,with 6 rabbits each.Thicker region of the left hepatic lobe was treated by custom-made non-focused ultrasound for 5 min.Peak intensity (PI) was used to evaluate the blood reperfusion of the target region after treatment.Liver specimens were performed transmission electron microscope examination immediately and 24 h after treatment to analyze ultrastructure changes.Results PI ratio in ultrasound-microbubble group (15.1 ± 2.6) was significantly lower than that in trauma group (23.1 ± 1.1) and ultrasound group (23.4 ± 1.3) (P ＜ 0.05).But the difference between trauma and ultrasound groups was insignificant (P ＞ 0.05).Compared with trauma and ultrasound groups immediately after treatment,hepatic cells in ultrasoundmicrobubble group had obvious edema,sinusoids thinned,organelles arranged in disorder,mitochondrial edema was present,endothelia cells of interlobular hepatic artery,interlobular vein and bile canaliculi in the portal area damaged,and microvilli of bile canaliculi disappeared.Hepatic cells showed morphology of apoptosis 24 h after treatment.Conclusion Microbubble-enhanced non-focused ultrasound can be used to make rapid hemostasis by decreasing the blood perfusion,but it causes certain damage to the ultrastructure of hepatic cells and may induce apoptosis in the radiation zone and neighboring cells.

Objective To investigate the MRI feature of fatigue fracture. Methods MRI of 11 cases of fatigue fracture was retrospectively analyzed and was confirmed by pathology and clinical diagnosis. Results The fracture line,swelling of marrow cavity and soft tissue were well demonstrated using MRI,especially T 2WI STIR images.Conclusion MRI is of great value in the early diagnosing of fatigue fracture for early treatment.

OBJECTIVE To study the causes and mechanism of auditory neuropathy. METHODS Auditory neuropathy is characterized by the DPOAE being normal, the shape of the pure tone loss being mostly in low frequencies, but the ABR being absent or the threshold elevated disproportionally to the pure tone threshold. Patients were screened from the deaf patients through asking the ill history and taking the exams of pure tone audiometry, auditory brain stem response, distortion product of otoaccoustic emissions (DPOAE). Thirty six patients were met the above standard. Deparaffined sections of cochlea of the guinea pigs were used as antigens to test whether the sera of patients had the autoantibodies with immunofluorescence method. RESULTS In the total of 36 patients with this type of hearing loss, autoantibodies were positive in 31 patients(86.1%). Twenty of the 31 patients had autoantibodiesto connective tissue of osseous spiral lamina where the nerve fiber connecting the hair cells and spiral ganglion cells go through. The autoantibodies to capsula surrounding the spiral ganglion and inner ear nerve fiber was also seen in these patients. In additional 7 patients, the autoantibodies to spiral ganglion cell nucleus and inner ear nerve fiber was detected. In the 44 control persons, 9.1% of them have the autoantibodies to inner ear tissues(P

Objective To evaluate the three-dimensional contrast-enhanced MR venography in assessment of the lower extremityveins.Methods 15 patients with lower extremity veins thrombosis confirmed by operation,DSA or ultrasonic were undergone directthree-dimensional contrast-enhanced MR venography using GE Signa 1.0T MR system.The demonstration of the lower extremity veins wasobserved.Results 3D deep or superficial vein images of low abdomen,pelvis and low extremity were acquired satisfactorily in all 15patients.Conclusion Direct three-dimensional contrast-enhanced MR venography is a favorable method in accessing lower extremity veins.