Objective To study the effect of methotrexate on the neointimal formation after arterial balloon injury. Methods Male rabbits were randomized into four groups: MTX 0.5 mg/kg per week, MTX 1.5 mg/kg per week, MTX 5 mg/kg per week and the control. Drugs were administered by intramuscular injection. Rabbit carotid arteries were harvested 2 and 4 weeks after injury. Results Histologically, the intimal areas were reduced significantly in MTX treated animals compared with the controls. The VSMC proliferation in injured vessels was identified by immunostaining for proliferating cell nuclear antigen (PCNA). In comparison, PCNA-positive cells in both intima and media were significantly reduced by treatment of MTX. But MTX did not enhance reendothelialization in the injured carotid arteries as determined by Evans blue stain.Conclusion Low dosage of MTX could attenuate neointimal formation after arterial injury by inhibiting VSMC proliferation.

A growing number of children and adolescents are being diagnosed as Chiari malformation type Ⅰ (CM-Ⅰ) for behavioral disorders,developmental delay,seizures,or abnormal orpharyngeal function.The aim of this study was to compare the clinical characteristics,imaging findings and surgical outcomes of CM-Ⅰ in pediatric and adult patients.Between January 2014 and June 2017,84 patients with CM-Ⅰ underwent surgical treatment in our department.We divided the patients into two groups:pediatric group (n=1 1,age ＜18 years)and adult group (n=73,age ≥18 years).Data on clinical characteristics,imaging findings,surgical outcomes,and prognosis were retrospectively reviewed and compared between these two groups.For clinical presentation,scoliosis (36.4％) and developmental delay (36.4％) were more common in pediatric patients,whereas,sensory disturbance (58.9％) and motor weakness (41.1％) were more common in adult patients.Imaging findings showed that the incidence of hydrocephalus and craniovertebral junctional abnormalities was significantly higher in pediatric group than in adult group (P＜0.05).Compared to adult group,pediatric group showed a better improvement or resolution of syrinx and tonsillar herniation after surgical treatments (P＜0.05).The total Chicago Chiari Outcome Scale (CCOS) score in pediatric patients at the last follow-up was significantly higher than that in adult patients (P=0.002).In conclusion,the clinical characteristics and imaging findings appeared to be different in pediatric and adult patients with CM-Ⅰ.The surgical outcomes of pediatric patients were shown to be significantly better than those of adult patients.

Aim To observe the effect of methotrexate (MTX) on proliferation, migration and apoptosis of cultured vascular smooth muscle cells (VSMC). Methods Rabbit thoracaortic VSMC were cultured in vitro.VSMC proliferation was evaluated by cell counting and cell cycle analysis. Monolayer cell scrape was used to observe VSMC migration. Apoptosis was observed with flow cytometry, DNA gel electrophoresis and TUNEL stain. Results MTX (25～100 nmol?L -1) inhibited VSMC proliferation in a dose-dependent manner.25 nmol?L -1 and 50 nmol?L -1 MTX increased the percentage of the S phase cells and decreased the percentage of the G 2/M phase cells (P

OBJECTIVETo assess the characteristics of enhanced magnetic resonance image with ultrasmall superparamagnetic iron oxide (USPIO) in the inflammatory and tumor metastatic rabbit model, and explore its relevance with histologic ultrastructural findings.

METHODSTotally 36 New Zealand white rabbits were randomly divided into lymphadenitis group and metastatic group. Complete Freund's adjuvant was injected into the bilateral dorsal footpads of 18 rabbits to set up ipsilateral lymphadenitis model. The other 18 rabbits received a subcutaneous implantation of VX2 tumor cell suspension (1.5 x 10(7) cells/ml) in both thighs to set up metastatic lymph node model. Magnetic resonance scan were performed 24 hours before and after USPIO (90 micromol Fe/kg) injection. T2 values of each lymph node were measured and lymph node T2 enhancement rate was calculated as well. HE staining, Prussian blue staining, and electronic microscopy were performed to observe the pathological microstructure changes and the distribution of the iron particle in lymph node. Relationship between lymph nodes USPIO enhancement and its microstructures were further analyzed. Results Thirty-six lymph nodes in lymphadenitis group showed different degrees of reactive hyperplasia. Twenty-six lymph nodes in metastatic group were invaded by tumor cell. Non-enhanced scan showed mild difference between T2 signal intensity of the two pathological lymph node types. After USPIO enhancement, inflammatory lymph nodes showed distinct T2 signal reduction at the center, and metastatic lymph nodes showed homogenous and faint T2 signal reduction. Enhancement rate of benign and malignant lymph nodes were 57.39% and 29.45% respectively (P < 0.01). HE staining and Prussian blue staining indicated USPIO particles located mainly in the macrophages at inflammatory lymphatic medulla, while paracortical area and cortical area contained relatively much less USPIO particles due to less macrophages distribution. MRI findings were correlated with the pathological results. Electronic microscopy also verified that the majority of USPIO particles were located in the numerous cytophagic bubbles of macrophages. Lymph nodes metastasis including 4 lymph nodes with completed structure destruction due to entire tumor infiltration, 19 lymph nodes with partially lymph node structure destruction but reduced USPIO-contained macrophage numbers or reduced USPIO particles in macrophages, and 3 lymph nodes with only localized foci tumor metastasis at subcapsular area. Conclusions USPIO enhancement pattern of different lymph nodes is closely related to distribution and functional status of the intra-node macrophages. It may affect the accuracy of the lymph node property diagnosis based on USPIO enhanced image.

Animals ; Dextrans ; metabolism ; Female ; Image Enhancement ; methods ; Lymph Nodes ; ultrastructure ; Lymphadenitis ; diagnosis ; pathology ; Lymphatic Metastasis ; diagnosis ; ultrastructure ; Magnetic Resonance Imaging ; methods ; Magnetics ; Magnetite Nanoparticles ; Male ; Nanoparticles ; Rabbits ; Random Allocation

OBJECTIVETo study the effect of THW-4, an extract from Trypterygium hypoglaucum on proliferation and apoptosis of vascular smooth muscle cells (VSMC).

METHODSVSMC derived from rabbit aorta were cultured in vitro and different concentrations of THW-4 were added in experimental groups. Cell proliferation was evaluated by MTT and apoptosis by transmission electron microscopy (TEM), TUNEL assay and Annexin V-FITC/PI double labelled assay.

RESULTSThe inhibitory effects of THW-4 on proliferation of VSMC displayed dose-time dependently, with the IC50 value of 15.6 microg/L at 48 hrs. Incubated with THW-4 (10-100 microg/L) for 56 hrs, VSMC mainly appeared early stage apoptosis and the percentage of apoptosis was found to raise along with the increase of the THW-4 concentration. Typical images of apoptosis could be observed under TEM and TUNEL assay showed increase of DNA segments with karyorrhexis and pyknosis after THW-4 treatment for 72 hrs. Analysis of cell cycle indicated the THW-4 mainly lead to the blockage of VSMC in G2/M stage.

CONCLUSIONTHW-4 could inhibit the proliferation and induce the apoptosis of VSMC in vitro, suggesting that THW-4 is a potential agent for prevention of restenosis following angioplasty.

Animals ; Aorta ; cytology ; Apoptosis ; drug effects ; Cell Division ; drug effects ; Cells, Cultured ; Coronary Restenosis ; prevention & control ; Drugs, Chinese Herbal ; pharmacology ; Male ; Muscle, Smooth, Vascular ; cytology ; Rabbits ; Tripterygium ; chemistry

AIMTo investigate the effects of morphine on synaptic transmission of neurons of central nervous system and reveal the mechanism underlying it.

METHODSNew born wistar rats were used for primary culture of hippocampus neurons. Using whole-cell patch-clamp technique, we observed the excitatory and spontaneous inhibitory postsynaptic current (EPSC, sIPSC) and glutamate-induced current before and after morphine treatment.

RESULTS(1) sEPSC of hippocampal neurons was markedly increased after morphine application. The effect of morphine was blocked by opioid antagonist naloxone (n=18, P < 0.01). (2) The frequency of mEPSC and the amplitude of glutamate-induced current of hippocampal neurons had no significant changes after morphine treatment (P > 0.05). (3) Morphine inhibited sIPSC of hippocampal neurons markedly and naloxone could block this effect (n=13, P < 0.01).

CONCLUSIONThe results suggest that the exciting effect of morphine on hippocampal neurons are not due to direct influence of morphine on glutamate synapses transmission, but may result from the inhibition on interneurons, that is "disinhibition" way.

Animals ; Animals, Newborn ; Cells, Cultured ; Excitatory Postsynaptic Potentials ; physiology ; Hippocampus ; cytology ; Inhibitory Postsynaptic Potentials ; Morphine ; pharmacology ; Neurons ; drug effects ; physiology ; Patch-Clamp Techniques ; Rats ; Rats, Wistar ; Synaptic Transmission ; drug effects ; physiology

BACKGROUNDUric acid (UA) is suspected to play a neuro-protective role in Parkinson's disease (PD). This study aimed to evaluate whether the serum UA level was associated with the disease progression of PD in a relatively large population of Chinese patients.

METHODSSerum UA levels were measured from 411 Chinese PD patients and 396 age-matched controls; following the uric acid colorimetric method, the serum creatinine (Scr) levels were also measured to reduce the bias caused by possible differences in renal excretion function. The disease progression was scored by Hoehn and Yahr (H&Y) scales and disease durations; PD group was divided into 3 subgroups according to H&Y scales. Independent-samples t test was performed to analyze the differences between PD group and control group. Multiple analysis of covariance was performed to analyze the differences between PD subgroups. Spearman rank-correlation was performed to evaluate the associations between serum UA or Scr level and disease progression.

RESULTSPD patients were found to have significantly lower levels of serum UA than controls ((243.38 ± 78.91) vs. (282.97 ± 90.80) µmol/L, P < 0.01). As the disease progression, the serum UA levels were gradually reduced. There was a significantly inverse correlation of UA levels with H&Y scales (Rs = -0.429, P < 0.01) and disease duration (Rs = -0.284, P < 0.01) in PD patients of both females and males. No significant difference of the Scr level between PD patients and controls was found ((70.01 ± 14.70) vs. (69.84 ± 16.46) µmol/L), and the Scr level was not involved in disease progression.

CONCLUSIONLower serum UA levels may possess a higher risk of PD, which may be a potential useful biomarker to indicate the progression of PD.

Aged ; Case-Control Studies ; Female ; Humans ; Male ; Middle Aged ; Parkinson Disease ; blood ; pathology ; Uric Acid ; blood

Adult ; CD5 Antigens ; metabolism ; Carcinoma, Papillary ; metabolism ; pathology ; Carcinoma, Squamous Cell ; metabolism ; pathology ; surgery ; Choristoma ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Hamartoma ; metabolism ; pathology ; Humans ; Proto-Oncogene Proteins c-kit ; metabolism ; Thymoma ; metabolism ; pathology ; Thymus Gland ; pathology ; Thymus Neoplasms ; metabolism ; pathology ; Thyroid Neoplasms ; metabolism ; pathology ; surgery ; Thyroidectomy ; methods

OBJECTIVETo observe the maximal heart rate changes, atrioventricular (A-V) conduction block and atrial fibrillation (AF) inducibility in dogs with vagosympathetic trunk exposed to electromagnetic fields (EMFs).

METHODSThe vagosympathetic trunk of adult dogs was separated and exposed to EMFs 0.043 kHz (2.87 microG, n = 5) and to EMFs 2 kHz (0.34 microG, n = 6) for two to three hours. Simultaneously, the vagosympathetic trunk was stimulated with 20 Hz frequency and 1 - 8 V intensity for 0.1 ms. Heart rate, presence of A-V conduction block and AF inducibility were determined.

RESULTSAfter 5-minutes exposure to EMFs 0.043 kHz (2.87 microG), the maximal heart rate decreased 29%, the voltage applied to vagosympathetic trunk required to induce A-V conduction block decreased by 60% in experimental group versus 5% increase in control group. This effect lasted 2 to 3 hours. While vagosympathetic trunk exposure to EMFs 2 kHz (0.34 microG) was associated with significant increase in the incidence of atrial premature beats, atrial tachycardia and AF, these effects could be blocked by propranolol and atropine.

CONCLUSIONSOur results showed that 0.043 kHz (2.87 microG) EMFs exposure might reduce while 2 kHz (0.34 microG) EMFs exposure might increase AF inducibility. Our study thus suggested autonomic nervous system of dogs could be affected by EMFs exposure and 0.043 kHz (2.87 microG) EMFs exposure might be a novel option for AF prevention.

Animals ; Atrial Fibrillation ; etiology ; physiopathology ; Dogs ; Heart Rate ; Magnetics ; Vagus Nerve ; physiopathology

OBJECTIVETo investigate the relationship between cell apoptosis and the quality of early mouse embryos, understand the significance of apoptosis-regulatory genes in early embryonic development, and explore a new approach to improving the embryo quality.

METHODSThe levels of cell apoptosis and proliferation in early mouse embryos in different developmental status (morphologically normal embryos, arrested embryos and fragmented embryos) were analyzed with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), caspase in situ fluorescence and Bcl-2 immunofluorescence, and immunofluorescent detection of proliferating cell nuclear antigen (PCNA).

RESULTSThe cells in arrested embryos and embryonic fragments showed positive results in TUNEL assay with enhanced caspase activity and lowered expressions of Bcl-2 and PCNA.

CONCLUSIONCell apoptosis in early mouse embryos may be closely related to embryonic arrest and fragmentation.

Animals ; Apoptosis ; Caspases ; metabolism ; Embryo, Mammalian ; cytology ; Female ; Mice ; Mice, Inbred Strains ; Pregnancy ; Proliferating Cell Nuclear Antigen ; metabolism ; Proto-Oncogene Proteins ; metabolism ; Proto-Oncogene Proteins c-bcl-2