OBJECTIVETo study the effect of nano-SiO2 on spatial learning and memory.

METHODSTwenty-four male rats were randomly divided into 3 groups: control group (C group), low dose group (L group) and high dose group (H group). The rats were intragastrically administrated with nanometer particles at 25 and 100 mg/kg body weight every day for 4 weeks. After exposure, the ability of learning and memory of rats was tested by Morris water maze, and electrophysiological brain stereotactic method was used to test long-tear potentiation (LTP) in dentate gyrus (DG) of the rats.

RESULTSThe increase rate of body weight in H group was reduced significantly compared with C group ( P < 0.05). In the space exploration experiment of Morris water maze test, the escape latency of H group was longer than that of C group (P < 0.05). The rats of H group spent less time in finding the target quadrant (P < 0.05) . The rate of LP induction of H group was significantly lower than that of C group (P < 0.05). After high fre quency stimulation (HFS), The changes of amplitude of population spike (PS) of L group and H group were lower than those of C group significantly (P < 0.05, P < 0.01).

CONCLUSIONNano-SiO₂may result in impairment of spatial learning and memory ability by reducing the rate of LTP induction and the increase of PS in hippocampus.

Animals ; Dentate Gyrus ; drug effects ; Long-Term Potentiation ; drug effects ; Male ; Maze Learning ; drug effects ; Memory ; drug effects ; Nanoparticles ; adverse effects ; Rats ; Silicon Dioxide ; adverse effects ; Spatial Learning ; drug effects

Objective To evaluate the clinical value of multi-slice CT(MSCT)angiography in the diagnosis of Takayasu's arteritis.Methods Fourteen patients underwent MSCT angiography with use of 90 ml contrast media at a rate of 3.5 ml/s.Images were generated for vascular assessment with various reconstructional techniques,including multi-planar reformat(MPR),maximum intensity projection(MIP), volume rendering(VR),CT virtual endoscopy(CTVE)and advanced vessel analysis(AVA).Results MSCT angiography findings was consistent with the clinical changes of Takayasu's arteritis in all cases.The integrated information including reconstructional and transverse images clearly presented various luminal abnormalities,such as stenosis,occlusion and dilatation in the affected aorta,as well as its major branches and collateral circulation.Furthermore,it depicted mural abnormities,especially concentric arterial wall thickening.Steno-occlusive type(8/14)was more common than mixed type(6/14).According to Lupi- Herrea's classification,type Ⅰ in 5 cases,type Ⅱ in 2,type Ⅲ in 6 and type Ⅳ in 1 were recorded in the present study.Conclusion MSCT angiography is reliable imaging modality for the detection of Takayasu's arteritis.It is useful for early diagnosis because it allows evaluation of wall thickness rather than merely the luminal diameter,which is especially important for prognosis.It might be used as the first choice in the diagnosis of this disease as a simple,convenient and noninvasive method.

OBJECTIVETo evaluate the value of magnetic resonance dynamic contrast-enhanced (MR-DCE) and magnetic resonance diffusion-weighted imaging (MR-DWI) in the differentiation of benign and malignant musculoskeletal tumors.

METHODSSixty-three patients with pathologically confirmed musculoskeletal tumors were examined with MR-DCE and MR-DWI. Using single shot spin echo planar imaging sequence and different b values of 400, 600, 800 and 1000 s/mm(2), we obtained the apparent diffusion coefficient (ADC) of the lesions. ADC values were measured before and after MR-DCE, with a b value of 600 s/mm(2). The 3D fast acquired multiple phase enhanced fast spoiled gradient recalled echo sequence was obtained for multi-slice of the entire lesion. The time-signal intensity curve (TIC), dynamic contrast-enhanced parameters, maximum slope of increase (MSI), positive enhancement integral, signal enhancement ratio, and time to peak (T(peak)) were also recorded.

RESULTSADC showed no significant difference between benign and malignant tumors when the b value was 400, 600, 800, or 1000 s/mm(2), and it was not significantly different between benign and malignant tumors in both pre-MR-DCE and post-MR-DCE with b value of 600 s/mm(2). TIC were classified into four types type1 showed rapid progression and gradual drainage; type2 showed rapid progression but had no or slight progression; type 3 showed gradual progression; and type 4 had no or slight progression. Most lesions of type1 or type2 were malignant, whereas most lesions of type 3 or type 4 were benign. When using type1 and type 2 as the standards of malignancy, the diagnostic sensitivity and specificity was 87.23% and 50.00%, respectively. The types of TIC showed significant difference between benign and malignant musculoskeletal tumors(χ(2)=17.009,P=0.001). When using MSI 366.62 ± 174.84 as the standard of malignancy, the diagnostic sensitivity and specificity was 86.78% and 78.67%, respectively. When using T(peak)≤70s as the standard of malignancy, the diagnostic sensitivity and specificity was 82.89%and 85.78%, respectively. Positive enhancement integral and signal enhancement ratio showed no significant difference between benign and malignant musculoskeletal tumors.

CONCLUSIONSTIC, MSI and T(peak) of MR-DCE are valuable in differentiating benign from malignant musculoskeletal tumors. T(peak) has the highest diagnostic specificity, and TIC has the highest diagnostic sensitivity. The mean ADC value are no significant difference between benign and malignant tumors.

Adolescent ; Adult ; Aged ; Bone Neoplasms ; diagnosis ; Child ; Diagnosis, Differential ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Muscle Neoplasms ; diagnosis ; Young Adult

OBJECTIVETo explore the effects of retinol acid (RA) and triiodothyronine (T3) on alleviating the impairment of cognitive function by sleep deprivation (SD).

METHODSMale Wistar rats were divided into 4 groups: control group (C group), sleep deprivation group (SD group), sleep deprivation + RA group (SD + RA group) and sleep deprivation + T3 group (SD + T3 group). Open field test (OFT) was used to observe the nervous behavior of the rats after SD and electrophysiological brain stereotactic method was used to test long-term potentiation (LTP) in dentate gyrus (DG) of the rats. Ng protein expression was determined by Western blot.

RESULTSCompared with the SD group, the number of crossing in OFT, the changes of amplitude of population spike (PS) and the expression of Ng protein in hippocampus were higher significantly in the SD + RA and SD + T3 groups. All of these had not significant difference comparing with the C group.

CONCLUSIONRA and T3 may alleviate the restrain state of neural system after SD by augmenting the expression of Ng protein in hippocampus.

Animals ; Cognition ; drug effects ; Dentate Gyrus ; metabolism ; Long-Term Potentiation ; Male ; Neurogranin ; metabolism ; Rats ; Rats, Wistar ; Sleep Deprivation ; metabolism ; psychology ; Triiodothyronine ; pharmacology ; Vitamin A ; pharmacology

OBJECTIVETo investigate the expression and the role of secreted frizzled-related protein 2 (SFRP2) in the earlobe keloid and find a valid way to treat the keloid with gene therapy.

METHODSThe expression of SFRP2 mRNA and protein was tested with in situ hybridization and Western Blot Analysis method in the different period of earlobe keloid.

RESULTSThe SFRP2 mRNA and protein expression at the keloid edge was significantly high in 12 month group than in 3 or 6 month groups (P < 0.01), but not than in 24 month group. The SFRP2 expression started to decrease in the keloid center 12 month later (P < 0.01). The SFRP2 expression was always higher in edge than in center during all the period (P < 0.05, P < 0.01).

CONCLUSIONSThe results suggest that SFRP2 may play an important role in the development of keloid, especially at the keloid edge. The high SFRP2 expression in endothelial cells and surrounding tissue is also important. It may be a new way for gene therapy of keloid by decreasing the SFRP2 expression.

Adolescent ; Adult ; Ear ; Female ; Humans ; Keloid ; metabolism ; Male ; Membrane Proteins ; metabolism ; Middle Aged ; Young Adult

OBJECTIVEBone marrow stromal cells (bMSCs) of rabbits transferred with mammalian hBMP-4 expression plasmid were used to construct tissue-engineered bone. Gene therapy combined with tissue-engineering technique was explored to further improve osteogenesis.

METHODSpEGFP-hBMP-4 plasmid was constructed by subcloning technique. bMSCs were then transferred with either pEGFP-hBMP-4, pEGFP plasmid by lipofectamine or left uninfected in vitro. The cells from the 3 groups were combined with natural non-organic bone (NNB) to construct tissue-engineered bones, which were subcutaneously implanted into nude mice (6 implants per group) for 4 weeks. Specimens were evaluated through histological and computerized new bone formation analysis.

RESULTSpEGFP-hBMP-4 plasmid was successfully constructed. bMSCs could attach and proliferate on the surface on NNB. In vivo experiment showed that new bone formation in pEGFP-hBMP-4 group was higher than those of the control groups.

CONCLUSIONSTissue-engineered bone using hBMP-4 gene modified bMSCs might be an ideal alternative for the repair of bone.

Animals ; Bone Morphogenetic Protein 4 ; Bone Morphogenetic Proteins ; genetics ; Genetic Therapy ; Humans ; Mice ; Mice, Nude ; Osteogenesis ; Rabbits ; Tissue Engineering

AIMTo observe the effects of adenosine on intracellular calcium concentration ([Ca2+]i) level in guinea pig ventricular myocytes and to define the possible mechanisms involved.

METHODSThe effects of adenosine on [Ca2+]i were investigated in guinea pig ventricular myocytes. [Ca2+]i was detected by laser confocal microscopy and represented by relative fluorescent intensity ((FI-FI0)/FI0, %, FIo: control, FI: administration of drugs).

RESULTS(1) Adenosine (10, 50, 100 micromol/L) reduced [Ca2+]i of ventricular myocytes in both normal Tyrode's solution and Ca(2+) -free Tyrode's solution in a concentration-dependent manner. (2) Tyrode's solution containing 30 mmol/L KCl (high K+ Tyrode's solution) induced [Ca2+]i elevation in ventricular myocytes, while adenosine (10, 50, 100 micromol/L) markedly inhibited the increase in [Ca2+]i induced by KCl. (3) Pretreatment with DPCPX (1 micromol/L) significantly reduced the effects of adenosine (100 micromol/L) in high K+ Tyrode's solution. The effects of adenosine (100 micromol/L) on [Ca2+]i in high K+ Tyrode's solution were also partially attenuated by pretreatment with L-NAME (1 mmol/L). (4) Adenosine (100 micromol/L) markedly inhibited the low concentration of ryanodine-induced [Ca2+]i increase in Ca(2+) -free Tyrode's solution. (5) When the propagating waves of elevated [Ca2+]i (Ca2+ waves) were produced by increasing extracellular Ca2+ concentration from 1 mmol/L to 10 mmol/L, adenosine (100 micromol/L) could block the propagating waves of elevated [Ca2+]i, reduce the frequency and duration of propagating waves, and reduce [Ca2+]i as well.

CONCLUSIONAdenosine may reduce the [Ca2+]i in isolated guinea pig ventricular myocytes via inhibiting Ca2+ influx and alleviating Ca2+ release from sarcoplasmic reticulum(SR). The reduction of Ca2+ influx might be due to the inhibition of voltage-dependent Ca2+ channel via adenosine A1 receptor, and NO might be involved in this process.

Adenosine ; pharmacology ; Animals ; Calcium ; metabolism ; Cells, Cultured ; Guinea Pigs ; Heart Ventricles ; cytology ; Myocytes, Cardiac ; drug effects ; metabolism

OBJECTIVETo study the protective effects of salidroside on injury induced by hypoxia/hypoglycemia in cultured SH-SY5Y cell.

METHODApoptosis and intracellular free calcium concentration ([Ca2+]i) were measured by flow cytometry, morphological changes and neuronal necrosis were observed with fluorescence microscope, and the lactic dehydrogenate (LDH) release was measured by LDH kits.

RESULTHypoxia/hypoglycemia cultures for 2 hours induced neuronal apoptosis and necrosis. They were 18.59% (P < 0.01) and 4.94% (P < 0.01) respectively. There were morphological changes including chromatin condensation, nuclear fragmentation and formed apoptotic bodies after exposed to hypoxia/hypoglycemia for 2, 4, 6, 12 hours. After 2 hours of hypoxia/hypoglycemia, neuronal [Ca2+]i and the release of LDH were significantly increased. They were 8.46 nmol/L (P < 0.01) and 16.59% (P < 0.01) respectively. The effects were enhanced with the extending time of hypoxia/hypoglycemia. Salidroside might have significantly decreased the percentage of neuronal apoptosis and necrosis, reduced neuronal [Ca2+]i and the release of LDH. The effects of salidroside were strengthened with the increasing of Salidroside dosage.

CONCLUSIONSalidroside has effect of anti-neuronal apoptosis. This effect might be related to its function of decreasing intracellular free calcium concentration.

Apoptosis ; drug effects ; Calcium ; metabolism ; Cell Hypoxia ; drug effects ; Glucosides ; isolation & purification ; pharmacology ; Humans ; Hypoglycemia ; metabolism ; pathology ; L-Lactate Dehydrogenase ; metabolism ; Neurons ; pathology ; Neuroprotective Agents ; pharmacology ; Phenols ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Rhodiola ; chemistry

OBJECTIVETo explore the angiogenesis and its maturation of hepatocellular carcinoma (HCC) and its correlation with deoxyhemoglobin parameters R2 * and T2 * values and the lesion/muscle R2*, T2 * ratio by using noninvasive magnetic resonance imaging (MRI).

METHODST2 *, R2 * values and the lesion/muscle R2 *, T2 * ratio in tumor periphery and center were calculated via series T2 * images in a total of 31 patients with surgically and pathologically confirmed HCC. After surgery, all sections were obtained from the specimen periphery in accordance with the MR analyzed areas. Continuous slices of each lesion were stained with hematoxylin-eosin (HE), and immunohistochemical staining was performed in vascular endothelial growth factor (VEGF), Flk-1, proliferating cell nuclear antigen (PCNA), CD34, and alpha smooth muscle actin (SMA). The expressions of VEGF, Flk-1, and PCNA index (PI) were evaluated. According to CD34 and SMA, some vascular parameters, including number, mean vessel area, total vessel area, circumference, diameter, distance between adjacent vessels, and variety index of microvessel and mature vessel, were calculated with a computed analysis system. The amounts of arterioles and veinlets, mature vessel index, and mean perfused fraction (mPF) were also recorded. All vessel parameters were compared with the calculated values of MRI.

RESULTSR2 * value or lesion/muscle R2 * ratio decreased and T2 * value or the lesion/muscle T2 * ratio increased in HCC when compared with hepatic parenchyma (P < 0.05); however, those values between lesion periphery and center and among different pathological grades were not significantly different (P > 0.05). T2 * value and the lesion/muscle T2 * ratio significantly decreased when the expression of VEGF was positive (P < 0.05). T2 * value was negatively correlated with microvessel amount (P = 0.047, r = - 0.639), while T2 * value and the lesion/muscle T2 * ratio were positively correlated with mPF (P = 0.040, r = 0.655; P = 0.048, r = 0.40, respectively). R2 * value was also positively correlated with mean area (P = 0.028, r = 0.688), total area (P = 0.021, r = 0.712) or circumference (P = 0.037, r = 0.663) of microvessel, and negatively correlated with mPF (P = 0.024, r = - 0.702). Meanwhile, the lesion/muscle R2 * ratio was positively correlated with mean area (P = 0.043, r = 0.647) and circumference (P = 0.026, r = 0.694) of microvessels.

CONCLUSIONR2 * or T2 * value may be influenced by the variation of deoxyhemoglobin caused by the heterogeneity of angiogenesis.

Adult ; Aged ; Carcinoma, Hepatocellular ; blood supply ; Female ; Hemoglobins ; Humans ; Liver ; pathology ; Liver Neoplasms ; blood supply ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Neovascularization, Pathologic

China ; Cognition ; Digestive System Surgical Procedures ; Enhanced Recovery After Surgery ; Humans ; Length of Stay