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OBJECTIVE: This study was purposed to evaluate the clinical efficacy of the treatment for acute cerebral infarction by intra-arterial thrombolysis combined with mild hypothermia. PATIENTS AND METHODS: Thirty patients, diagnosed with acute anterior circulation cerebral infarction and admitted to the Hospital between January 2013 and September 2015, were randomly divided into the control group and the mild hypothermia group, each group comprising 15 cases. The treatment of intra-arterial thrombolysis combined with mild hypothermia was administered to the mild hypothermia group, while only the treatment of intra-arterial thrombolysis was performed on the control group. The National Institutes of Health Stroke Scale (NIHSS) score, Modified RANKIN Scale (MRS) score, cerebral hemorrhage transformation, pulmonary infection, and the incidence of gastrointestinal bleeding of the two groups were compared on day 14, 30, and 90 following the on-set of the disease. RESULTS: The prognosis (MRS score) of the group with mild hypothermia combined with intra-arterial thrombolysis was lower than that of the group treated only with intra-arterial thrombolysis (p < 0.05). The incidence of cerebral hemorrhage transformation of the group with mild hypothermia combined with intra-arterial thrombolysis was also lower than that of the control group (p < 0.05). There was no significant difference in the incidence of pulmonary infection and gastrointestinal bleeding between the two groups. CONCLUSIONS: Treatment of patients suffering from acute cerebral infarction by means of intra-arterial thrombolysis in combination with mild hypothermia can result in reduced risk of hemorrhagic transformation and improve clinical outcome. [ABSTRACT FROM AUTHOR]

The design, fabrication and performance of a reflection-type tunable phase shifter based on a lead zirconate titanate (PZT) thin-film process is presented. The phase shifter consists of a coplanar waveguide Lange coupler on high resistivity silicon (HRSi) and two ferroelectric PZT varactors. At 12 GHz, the varactors achieve a capacitance tuning range of 5.5 to 1 along with a phase shift of 86° with bias voltages in the range 0–26 V. Analysis of the losses due to the varactors and the rest of the phase shifter is also presented. [ABSTRACT FROM AUTHOR]

A technique for realising nonlinear functions of order a 5 using cascaded third-order nonlinear functions is described. The technique can be used to efficiently generate higher-order nonlinearities for predistortion linearisation applications. The use of two cascaded third-order functions is experimentally demonstrated to be comparable to a fifth-order implementation in performance. [ABSTRACT FROM AUTHOR]

TiO2 films doped with ZnFe2O4 were prepared by a sol–gel method. The crystalline structure, photocatalytic efficiency and optical absorption band were investigated using X-ray diffraction and Ultraviolet-Visible spectrometer. The doping of ZnFe2O4 improves the photocatalytic efficiency and broadens the optical absorption band of TiO2 films. The photocatalytic efficiency of TiO2 films increases from 12 to 32% with the presence of ZnFe2O4. The exciting wavelength of TiO2 films shifts about 20 nm to the visible light regions when the molar ratio of ZnFe2O4 is 2%. [ABSTRACT FROM AUTHOR]

Objective: To construct a preoperative evaluation system for partial nephrectomy using CT three-dimensional visualization technology and to explore its practical value., Methods: The clinical data of the patients who underwent partial nephrectomy for renal tumors in Department of Urology, Peking University First Hospital were collected retrospectively. At the same time, the homogenized standard data of patients who underwent partial nephrectomy for renal tumors were collected in 16 clinical centers in China. The CT three-dimensional visualization system was applied (IPS system, Yorktal) to evaluate tumor anatomy, blood supply, perirenal fat and other information. The parameters were summarized to build a three-dimensional nephrometry system, on the basis of which virtual surgery design and intraoperative navigation were completed., Results: A three-dimensional visualization image was established based on the enhanced CT urography. The nephrometry system included the longest diameter and volume of the tumor, proportion volume of tumor invading the parenchyma, maximum depth of the tumor invading the parenchyma, contact surface area, flatness of the tumor surface, renal segment where the tumor was located, vascular variation, and perirenal fat. The average two-dimensional diameter of the tumor was (2.78±1.43) cm, the average three-dimensional maximum diameter was (3.09±1.35) cm, and the average postoperative pathological size was (3.01±1.38) cm. The maximum tumor diameter in the three-dimensional image was significantly related to the prolonged renal artery clamping time and intra-operative blood loss ( r =0.502, P =0.020; r =0.403, P =0.046). The three-dimensional and pathological tumor volume were (25.7±48.4) cm 3 and (33.0±36.4) cm 3 , respectively ( P =0.229). The tumor volume was significantly related to the intraoperative blood loss ( r =0.660, P < 0.001). The proportion volume of the tumor invading into renal parenchyma was significantly related to the prolongation of renal artery clamping and the occurrence of postoperative complications ( r =0.410, P =0.041; r =0.587, P =0.005). The tumor contact surface area and the presence of vascular variation did not show correlation with the perioperative data and postoperative complications. While the preoperative evaluation was completed, the reconstructed three-dimensional image could be zoomed, rotated, combined display, color adjustment, transparency, and simulated cutting on the Touch Viewer system. The process generally consisted of showing or hiding the tissue, adjusting the transparency of the interested area, rotating and zooming the image to match the position of the surgical patient. Together, these functions met the requirements of preoperative virtual surgery plan and intraoperative auxiliary navigation., Conclusion: Three-dimensional images can provide a more intuitive anatomical structure. The CT three-dimensional visua-lization system clearly displays tumor anatomical parameters, blood supply and perirenal fat. The three-dimensional nephrometry system for renal tumors can help predict the difficulty of partial nephrectomy and perioperative complications. Importing the reconstructed three-dimensional visualization image into the specified program or robot operating system can complete virtual surgery and intraoperative navigation, helping the surgeon to better grasp the surgical process. The indexes included in the nephrometry system and the score weights of each index need to be confirmed and perfected by multi-center study with large samples.

Objective: To deepen our understanding of Methylmalonic aciduria (MMA) associated pulmonary hypertension (PH) by analyzing the characteristics of clinical presentation, pulmonary high resolusion CT(HRCT), treatment response and gene mutation., Methods: This study includes 15 cases of pediatric patients with MMA associated PH diagnosed and treated in Peking University First Hospital pediatric department between May 2012 and May 2016 with symptoms of PH as their leading presentation. Clinical symptoms and signs were recorded, Routine blood laboratory examinations was done including arterial blood gas analysis. Plasma total homocysteine (Hcy) and brain natriuretic peptide(BNP) level were measured. MMA gene mutation was analyzed. Chest HRCT was done in most of the patients. Standard treatment strategy to MMA and PH was given and follow up study was done, and the related literature was reviewed. Statistical analysis was done. The diagnosis of MMA was made by methylmalonic acid level >100 times the normal value in the urine. The diagnosis of PH was made by pulmonary arterial systolic pressure (PASP)>40 mmHg, which was estimated by the measurement of tricuspid regurgitation velocity through Doppler Echocardiography., Results: (1) Patient characteristics: There were 10 male and 5 female patients diagnosed as MMA associated PH, aged 0.5 to 13.8 years, with an average of (5.0±4.3) years. The age of onset of PH was (3.7±3.5) years, with an early onset type MMA in 5 cases and late-onset type in 10 cases. (2) Clinical presentation: Among the 15 cases of MMA, the first symptoms were associated with PH in 10 cases, so PH and MMA were diagnosed at the same time, and PH was diagnosed 3 to 72 months post MMA presentation in the other 5 cases. The main presentations of PH were techypnea/dyspnea and cyanosis in 11 cases each, weakness and fatigue on exertion in 6 cases, and edema in 4 cases. PH WHO functional classification (WHO FC) was Class II in 4 , Class III in 5 and Class VI in 6 cases, with an average of Class 3.1±0.8. Multi-system involvements were common with the highest frequency in the kidney (14 cases). Macrocytic anemia was present in 8 cases and sub-clinical hypothyroidism in 5 cases, and mild to moderate mental retardation in 4 cases. (3) Laboratory examination: PASP of the 15 patients was from 49 to 135 mmHg, with an average of (90.3±23.9) mmHg. Total blood Hcy level was severely elevated to (121.2±48.2) μmol/L (range: 35.0-221.0 μmol/L), and Hcy >100 μmol/L within 11 cases. Plasma BNP level was also elevated, median 794 ng/L (range: 21.0-4 995.0 ng/L) with 12 cases >300 ng/L. Blood gas analysis showed low arterial blood oxygen saturation between 70% and 94%, with an average of 81.4%±8.4%. (4) Chest HRCT: chest HRCT showed a diffuse ground-glass centrilobular nodular opacities with septal line thickening in the lungs in 9 cases, and with associated mediastinal lymph node enlargement in 1 case, which indicated pulmonary veno-occlusive disease (PVOD), a rare type of pulmonary arterial hypertension (PAH). There was lung infection or edema in 3 cases, and interstitial infiltration and mesh-like feature in other 3 cases, which was inferred to interstitial lung disease. (5) Gene mutation: Genetic testing was done in 10 cases, totally 5 reported disease-causing mutations were found. There were 100% presence of MMACHC c.80A>G mutation in all the 10 patients tested, with the allelic genes of c.609G>A mutation in 6 patients, including a sister and a brother from the same parents. (6) Treatment and follow up: Intramuscular hydroxocobalamin or vitamin B12 was given to all of the patients, together with betaine, levocarnidtine, folinic acid and vitamin B6. According to the severity of PH, single or combined PAH targeted drugs was given to 11 cases. By an average of (20.0±13.5) days of in-hospital treatment in 13 patients (excepting 1 case treated as outpatient), symptoms remarkably resolved, WHO FC reduced to an average of Class 2.4±0.9, PASP dropped to (69.4±21.3) mmHg, and plasma Hcy and BNP level were decreased to (74.9±25.9) μmol/L and (341.6±180.2) ng/L, respectively. The above values all reached statistical significance (P<0.05) compared with each related value before treatment. There were 2 patients who expired during hospitalization despite of treatment. At the end of 3 months' follow up, all of the 13 patients disposed oxygen, and PASP significantly dropped to 38.7±7.9 mmHg, and plasma BNP returned to normal, but plasma Hcy level showed no further decline. At the last follow up of 27.5±19.0 (range: 11-64) months, all the patients' PASP remained normal except for the 13.8-year-old boy with 6 years-long history of MMA and almost 3.6 years' history of PH still having PASP 58 mmHg., Conclusion: PH is a severe complication of MMA combined type, especially cblC type, it is more often happens in late-onset type of male patients and can be the first and leading manifestations of MMA. Its clinical symptoms are urgent and severe, characterized by tachypnea/dyspnea and cyanosis, and sometimes right heart failure, hypoxemia is usually present, chest HRCT is often indicative of PVOD, lung edema and interstitial lung disease may occur. Rapid diagnosis and targeted treatment of MMA with appropriate anti-PAH medication can reverse PH and save life. MMACHC gene c.80A>G mutation may be the hot point of MMA cblC type associated PH.

Objective: To study the effect of plumbagin on epithelial-mesenchymal transition (EMT) and underlying mechanisms in human tongue squamous cell carcinoma (TSCC) cells. Methods: Methyl thiazolyl tetrazolium assay was apllied to examine the proliferation inhibition effect and half maximal inhibitory concentration (IC(50)) of plumbagin (0.1, 1.0, 5.0, 10.0, 20.0 μmol/L) in 12, 24, 48 h in TSCC cells. Transwell assay was used to count the number of transmembrane cells and scratch test was performed to examine cells mobility. The flow cytometry was applied to measure intracellular reactive oxygen species (ROS) level in control group, plumbagin group (1.0 μmol/L, 24 h) and glutathione (GSH)+plumbagin group. The expression of E-cadherin, vimentin, Slug, p38 mitogen activated protein kinases (p38MAPK) and phospho-p38MAPK (p-p38MAPK) proteins were determined by Western blotting. The expression of E-cadherin, vimentin and Slug were detected by Western blotting in control group, plumbagin group, activator combined group (p38MAPK activator+plumbagin) and inhibitor combined group (p38MAPK inhibitor+plumbagin). Results: After the treatment of plumbagin for 12, 24, and 48 h, the IC(50) of TSCC cells were 10.3, 3.1, 1.5 μmol/L. After treated by 1.0 μmol/L plumbagin for 24 h, the number of transmembrane cells were significantly reduced ([50±13], P< 0.05) in comparison to control group (204±6), as well as the cells mobility ([18.2±2.3]%, P< 0.05) in comparison to control group ([49.3±1.2]%). Compared to control group (2.32±0.52), the ROS level was increased in plumbagin group (902.20±10.69), while compared to plumbagin group, the ROS level was reduced in GSH combined group (2.18±0.15). In comparison to control group, the expression of E-cadherin was up-regulated ( P< 0.05), and vimentin, Slug, p-p38MAPK/p38MAPK were down-regulated in plumbagin group ( P< 0.05). In comparison to plumbagin group, the expression of E-cadherin was down-regulated ( P< 0.05), and vimentin, Slug, p-p38MAPK/p38MAPK were up-regulated in GSH combined group ( P< 0.05). Treatment of cells with p38MAPK activator could decrease the expression of E-cadherin significantly ( P< 0.05) and increase the expression of vimentin ( P< 0.05) and Slug ( P< 0.05) in comparison to plumbagin group. Treatment of cells with p38MAPK inhibitor could increase the expression of E-cadherin significantly ( P< 0.05) and decrease the expression of vimentin ( P< 0.05) and Slug ( P< 0.05) in comparison to plumbagin group. Conclusions: Plumbagin inhibits EMT via ROS/p38MAPK-mediated pathway in human TSCC cells.

Objective: To investigate the clinical characteristics and prognosis of mediastinal fibrosis. Methods: Twelve patients with mediastinal fibrosis diagnosed between 2008 and 2015 in our hospital were studied retrospectively. Clinical manifestations, radiological characteristics, endoscopic features, treatment and prognosis were analyzed. Results: There were 3 males and 9 females, with a mean age of 68.8 years.Six patients had previous tuberculosis infection. The most common clinical symptoms were dyspnea on exertion (11 cases), cough (7 cases), and wheezing (6 cases). Chest CT scans revealed an infiltrative mediastinal process, with a discrete mass, enlargement of mediastinal lymph nodes, mediastinal lymph node calcification (9 case). Twelve patients had bronchial and pulmonary artery compression at lobar or segmental levels, 7 cases had localized pulmonary edema, and 6 cases had pulmonary atelectasis. The principal findings of bronchoscopy were distortion of bronchus with stenosis, multiple pigmentation of bronchial mucosa, and bronchial mucosal edema. Pulmonary hypertension (PH) was the main severe complication. One patients suffered from sudden death after bronchoscopy. Eleven patients were followed for 3 month to 7 years, and 5 patients got progression. Anti-tuberculosis therapy with or without corticosteroid was not beneficial. Conclusion: Tuberculosis was the leading cause of mediastinal fibrosis in our study, which was characterized with diffuse bronchial and pulmonary artery compression at lobar or segmental levels, and multiple pigmentation of bronchial mucosa.Anti-tuberculosis therapy with or without corticosteroids was not beneficial.

The only established physiological function of the V(D)J recombinase, comprising RAG1 and RAG2, is to perform DNA cleavage. The molecular roles of RAG2 in cleavage, the mechanisms used to join the broken DNA ends, and the identity of nuclease(s) that open the hairpin coding ends have been unknown. Site-directed mutagenesis targeting each conserved basic amino acid in RAG2 revealed several separation-of-function mutants that address these questions. Analysis of these mutants reveals that RAG2 helps recognize or cleave distorted DNA intermediates and plays an essential role in the joining step of V(D)J recombination. Moreover, the discovery that some mutants block RAG-mediated hairpin opening in vitro provides a critical link between this biochemical activity and coding joint formation in vivo.

The RAG proteins cleave at V(D)J recombination signal sequences then form a postcleavage complex with the broken ends. The role of this complex in end processing and joining, if any, is undefined. We have identified two RAG1 mutants proficient for DNA cleavage but severely defective for coding and signal joint formation, providing direct evidence that RAG1 is critical for joining in vivo and strongly suggesting that the postcleavage complex is important in end joining. We have also identified a RAG1 mutant that is severely defective for both hairpin opening in vitro and coding joint formation in vivo. These data suggest that the hairpin opening activity of the RAG proteins plays an important physiological role in V(D)J recombination.

Although gangliosides elicit human autoantibodies, they are extremely weak immunogens in mice. We obtained a monoclonal antibody Fab fragment (clone 10) that is specific for asialo GM1 (GA1), from a phage display library. The Vkappa domain of clone 10 could be replaced by two different Vkappa domains without changing the specificity of the antibody. Mutagenesis of the third hypervariable regions of the heavy and light chains of clone 10 yielded three mutants that exhibited a 3 to 4 times increase in avidity for GA1. A molecular model of clone 10 indicated that the putative antigen-binding site contained a shallow surface pocket. These data illustrate the use of recombinant DNA techniques to obtain anti-ganglioside antibodies, and to explore the molecular basis of their antigen-binding activity.

In order to elucidate the different results obtained in cancer patients with similar condition and symptoms treated by the same medicinal herbs, an investigation of the utensils used for making decoctions was carried out. It was found that the decoction made by means of glassware, enamel and earthenware pots had the best effect of inhibiting the colony formation of human gastric carcinoma cells, the next were the decoctions made by means of unrefined iron pots, stainless steel pots and copper pots, and the worst was that made with aluminium pots. It was also found that there was no difference between the water contained in those utensils and normal saline in the influence on the colony formation of human gastric carcinoma cells. Therefore, it is believed that the difference in effect of the decoctions made by means of different kinds of utensils is not due to the trace dissolution of the utensil materials, but is most likely due to the occurrence of some chemical reactions while making the decoction. That the decoctions made by means of different utensils had different peak values in the absorption spectrum also supports this proposition.