〔Abstract〕 Based on analyzing the background of generic drugs research and development, the paper elaborates the utilization meth-ods of drugs invalid patents, including information sources optimization and retrieval, invalid patents selection indexes and methods, in-fringement avoidance strategy.It takes the gastrointestinal stromal tumor drugs for example to find out drugs which can be imitated, pros-pects the future application of invalid patents information.

Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Stem Cells

ObjectiveTo investigate the correlation between the level of resistin and the insulin resistance(IR) and the incorporation of microamount albuminuria(MA) of type 2 diabetes mellitus (T2DM).MethodsTwo hundred and twenty T2DM patients and 40 normal subjects (control group) were enrolled in this study.Two hundred and twenty T2DM patients were divided into 4 groups,IR group (group A,79 cases),non-IR group (group B,48 cases),IR complicating MA group (group C,51 cases),non-IR complicating MA group(group D,42 cases).The fasting serum resistin was measured by enzyme-linked immunosorbant assay (ELISA),and the fasting plasma glucose (FPG),glycosylated hemoglobin (HbA1c),fasting insulin (FINS) was also determined.ResultsThe level of fasting serum resistin in group A,B,C and D was higher than that in control group [(33.45 ± 1.37),(23.36 ± 1.47),(44.45 ± 1.39),(37.45 ±1.57) μ g/L vs.( 17.44 ± 1.26 ) μ g/L],and there was significant difference among 5 groups (P ＜ 0.01 ).The level of fasting serum resistin in group A was higher than that in group B (P ＜ 0.01 ),and the level of fasting serum resistin in group C was higher than that in group D (P ＜ 0.01 ).The level of fasting serum resistin was both higher in group C and D than that in goup A and B (P＜ 0.01 ).Correlation analysis showed the fasting serum resistin was positively correlated with body mass index(BMI),FPG,HbA1c and FINS in group A(r =0.35,0.46,0.37,0.49,P ＜0.05),and the fasting serum resistin was positively correlated with HbA1c,BMI,systolic blood pressure and diastolic blood pressure in group C(r =0.45,0.32,0.37,0.29,P ＜ 0.05 ).ConclusionsSerum resistin may participate in the process of IR and the formation of MA.It may become one of the diagnostic standard of the IR and one of the important index to estimate the MA.

Objective To evaluate clinical application of phage amplified biologically assay (PhaB) in susceptibility test of Mycobacterium tuberculosis (MTB) in sputum. Methods The drug susceptibility of MTB was detected by PhaB in 143 patients with sputum-positive pulmonary tuberculosis (PTB),and the chemotherapy regimens were adjusted according to the results of susceptibility test.Independent samples t-tests were used for comparison of means.Count numbers were compared with Chisquare test.If there were count number of 0,Fisher probabilities should be used.ResultsThe total positive rate of PhaB was 94.4％ (135/143) with no differences between three types of PTB (x2 =1.886,P ＞ 0.05 ).The duration of testing for PhaB group was (6.6 ± 1.8) days,while for control was (29.4 ±8.7) days (t =29.01,P ＜ 0.01 ).Compared with control group,the 2-month negative-conversion rate (63.2％ vs.35.1％,x2 =3.989,P ＜ 0.05 ) and cure rate ( 100％ vs.78.4％,P ＜ 0.05 ) of PhaB group in type Ⅱ patients were significantly higher.But there were no differences between PhaB and control groups in type Ⅰ and Ⅲ PTB patients.ConclusionThe results of PhaB drug susceptibility test can be helpful for choosing effective chemotherapy regimen for PTB patients rapidly.

BACKGROUND: Embryonic stem cells (ESCs), the seed cells of all mature cells in vivo, are useful tools for nerve transplantation and developmental gene function research. Notch1 signaling pathway is the key pathway to control the ordered neural development and differentiation of many kinds of neural cells, however, there is no report on the dynamic expression of Notch1 signal during the ESC differentiation to date. OBJECTIVE: To investigate the expression of Notch1 protein, transmembrane signal transduction molecule, during directional differentiation of embryonic stem cells into neural cells. DESIGN, TIME AND SETTING: Cell research was carried out between October 2003 and October 2004 at Zhongshan Ophthalmic Center, SUN Yat-sen University, Guangzhou, Guangdong Province, China. MATERIALS: BALB/C mouse embryonic stem cell line Ⅵ (passage 11)was obtained from experimental animal center of SUN Yat-sen University, provided by professor Huang Bing. ESC culture medium was high-glucose DMEM medium with 20% bovine serum and 106 IU/L mouse leukemia inhibitory factor. Induced differentiation medium was high-glucose DMEM medium with 20% fetal bovine.serum and 5×107 mol/L retinoid acid(RA). METHODS: Passage 11 ESCs were resuscitated and incubated by ESC culture medium in incubator at 37℃ with 5% CO2. Passage 11 ESCs were subcultured after 2 or 3 days and RA was added into medium to induce differentiation. Three time points for observation were established: induced for 1, 5 and 9 days. MAIN OUTCOME MEASURES: Morphological changes were observed under inverted phase contrast microscope, MAP-2 antigen expressed in differentiated cells was detected by immunofluorescence method. Immunocytochemistry, Western Blot, flow cytometry assay were used to investigate the Notch1 protein expression. RESULTS: ESCs presented clone-like growth. After induced by RA for 9 days, single neural network was achieved around most of the cell clusters. With the prolongation of induction, MAP-2 positive neural cells increased gradually. Almost all ESC clones expressed Notch1 protein strongly or positively, but Notehl protein expression decreased gradually after induced differentiation (P < 0.01). CONCLUSION: Notch1 signal shuts off progressively during induction of ESCs into neural cells, which suggests Notch1 may play an important role in the differentiation of ESCs into neural cells.

Objective To investigate the incidence of left-sided portal hypertension (LSPH) in chronic pancreatitis (CP) and other accompany conditions of CP and explore the diagnostic value of LSPH in chronic pancreatitis.Methods The clinical,pathological and imaging data of 125 CP patients received at least two imaging examination were retrospectively analyzed.The rates of abnormal pathologic findings,abnormal imaging findings and accompanying LSPH in CP were analyzed.The data were analyzed by chi-square test.Results Among 125 CP patients,29.6％ (37/125) received three or more than three kinds of imaging examinations.The pathological detection rates of pancreatic calcification or lithiasis,pancreatic ductal lesion,abnormal pancreatic morphology,pancreatic lesion and LSPH were 58.4％ (73/125),60.8％ (76/125),35.2％ (44/125),48.8％ (61/125) and 24.8％ (31/125),respectively.The sensitivities of imaging examination in those lesions were 68.5 ％(50/73),96.1％ (73/76),95.5％ (42/44),95.1％ (58/61) and 90.3％ (28/31),respectively.The detection rates of pancreatic calcification or lithiasis and pancreatic ductal lesion in pathological examination were significantly higher than those of the others,and differences were statistically significant (x2=33.764 and 37.932,both P＜0.01).The sensitivity of imaging examination in pancreatic calcification or lithiasis was lower than those of the others and the differences were statistically significant (x2 =36.526,P＜0.01).Among 125 CP patients with 223 pancreatic lesions detected by imaging examination,the rates of patients with 0,1,2,3,4 lesions accounted for pancreatic were 5.6％ (7/125),40.0％ (50/125),28.8％ (36/125),21.6％ (27/125) and 4.0％ (5/125),respectively.Of patients with pancreatic calcification or lithiasis,pancreatic ductal lesions,abnormal pancreatic morphology and pancreatic lesions detected by pathological examination,there were 23.7 ％(17/73),20.0％ (15/76),22.6％ (10/44) and 27.9％ (17/61) cases accompanied with LSPH,there was no difference between these groups (x2 =1.262,P=0.738).Conclusion LSPH may be a reference for CP diagnosis by imaging examination.

Objective To evaluate the value of 18F-FDG PET/CT in assessing radiosensitivity enhancement by irisquinone (IR) on rabbit xenografted VX2 lung tumor models.Methods Twenty-four tumor-beating rabbits were randomly divided into 3 groups (8 rabbits/group):group A with radiotherapy alone,group B with combined radiotherapy and IR,and group C without radiotherapy (the control group).18F-FDG PET/CT imaging was performed before radiotherapy and 24 h and one week after radiotherapy.The tumor SUVmax on delayed imaging was calculated in all rabbits.Two rabbits in each group were sacrificed after PET/CT imaging.HE staining was used to assess the differences in cancer cells among groups.Paired t test,one-way analysis of variance and Kaplan-Meier analysis were performed to analyze the data using SPSS 13.0.Results Before radiotherapy,the tumor SUVmax of all the 24 rabbits on standard and delayed imaging were 2.200 ± 0.761 and 3.162 ± 0.833 (t =-5.582,P ＜ 0.01).At 24 h post-radiotherapy,the delayed SUVmax of groups A,B and C were 2.614 ± 0.654,2.349 ± 0.869 and 5.663 ± 1.144,respectively.The differences between pre-radiotherapy and 24 h post-radiotherapy were statistically significant in all three groups (t =2.527,3.620,11.011,all P ＜0.05).One week after radiotherapy,the delayed SUVmax of groups A,B and C were 3.625 ± 1.064,3.058 ±0.850 and 7.424 ± 1.751,respectively.The differences among groups A,B and C were statistically significant (tA∶ B =2.652,tA∶C =3.799,tB∶C =4.366,all P ＜0.05).The cancer cells of group B were fewer than those of groups A and C by pathological findings,which was consistent with 18F-FDG PET/CT results.The survival times of groups A,B and C were (62.375 ±4.534),(69.000 ±4.660) and (54.125 ±5.276) d,respectively.Kaplan-Meier survival curves revealed better survival of group B as compared to groups A and C,respectively (Log-rank,x2 =7.355,16.943,both P ＜ 0.01).Conclusion 18 F-FDG PET/CT is able to evaluate the effect of irisquinone on tumor radiosensitivity enhancement.

Tensegrity structure is comprised of compression-resis tant elements and a set of continuous tensile elements that are interconnected w ith each other. The stability of such system depends on maintenance of tensional integrity inside the structure, or what has come to be termed “tensegrity”. A ccording to studies on biology, cell structures are assembled on the basis of te nsegrity mechanism. Tensegrity of cytoskeleton can affect cell shape and functio n. Furthermore, some basic rules of mechanochemical transduction in cells can be well explained using tensegrity theory.

Objective To evaluate the effect of dexmedetomidine on myocardial injury induced by renal ischemia-reperfusion (I/R) injury in rats.Methods Twenty-four male Wistar rats,weighing 280-300 g,were randomly divided into 3 groups (n =8 each):sham operation group (group S),group I/R and dexmedetomidine group (group Dex).Renal ischemia was induced by occlusion of bilateral renal arteries for 45 min followed by reperfusion in I/R and Dex groups.At 20 min before ischemia,dexmedetomidine 50 μg/kg was injected intraperitoneally in group Dex,and the rest procedures were similar to those previously described in group I/R.The rats were sacrificed at 24 h of reperfusion and myocardial specimens were obtained for determination of malondialdehyde (MDA) content and superoxide dismutase (SOD) activity.The apoptosis in cardiomyocytes was examined by flow cytometry.Apoptosis index was calculated.The expression of Bcl-2 and Bax was detected by immunohistochemistry,and Bcl-2/Bax ratio was calculated.Results Compared with group S,apoptosis index and MDA content were significantly increased in I/R and Dex groups,Bcl-2/Bax ratio was decreased in group I/R,and Bcl-2/Bax ratio was increased in group Dex.Compared with group I/R,apoptosis index and MDA content were significantly decreased,and SOD activity and Bcl-2/Bax ratio were increased in group Dex.Conclusion Dexmedetomidine can attenuate myocardial injury induced by renal I/R in rats,and the mechanism may be related to inhibited apoptosis in cardiomyocytes and reduced lipid peroxidation.

Objective To investigate the relationship of the serum levels of high sensitivity C-reactive protein(hs-CRP) and homocysteine with middle cerebral artery(MCA) intraplaque hemorrhage.Methods A total of 63 patients who met the inclusion criteria showed high-grade(≥ 70％)MCA stenosis.The levels of serum hs-CRP and Hcy were detected.All patients were divided into symptomatic group and asymptomatic group,intraplaque hemorrhage group and non-intraplaque hemorrhage group.All patients performed conventional MRI and high-resolution MRI(HR-MRI).The correlation of the serum levels of hs-CRP and homocysteine with middle cerebral artery intraplaque hemorrhage was analyzed.Results Totally 37 symptomatic and 26 asymptomatic MCA stenoses were analyzed.The occurrence rate of intraplaque hemorrhage was significantly higher in symptomatic MCA stenosis group than in asymptomatic MCA stenosis group (40.5 ％ vs.11.5 ％,x2 =6.29,P＜ 0.05).Symptomatic group displayed a higher hs-CRP and Hey levels (8.97 ± 3.36 mg/L and 20.00 ± 3.16 μmol/L,respectively) than did asymptomatic group [(5.26 ± 3.12) mg/L and (12.22 ± 1.88) μmol/L,t =4.43 and 11.23,respectively,each P ＜ 0.001].The hs-CRP and Hcy levels were higher in intraplaque hemorrhage group [(10.53 ± 3.59) mg/L and (21.70 ± 2.40) μmol/L,respectively] than in non-intraplaque hemorrhage group[(6.20 ± 3.02) mg/L and(11.77±1.69) μmol/L,t=4.87 and 18.58,respectively,each P＜0.001].The hs-CRP and Hcy levels were positively correlated with the risk for middle cerebral artery intraplaque hemorrhage(r=0.461 and 0.519,each P＜0.001).Conclusions The serum levels of hs-CRP and Hcy are closely associated with middle cerebral artery intraplaque hemorrhage,which can be used to evaluate the stability of plaque.The MCA intraplaque hemorrhage is associated with ipsilateral stroke.