Choristoma ; Humans ; Male ; Middle Aged ; Thyroid Gland ; pathology ; Tracheal Diseases

Humans ; Male ; Middle Aged ; Thyroid Cartilage ; abnormalities

Aged ; Antineoplastic Agents ; therapeutic use ; Benzamides ; therapeutic use ; Drug Resistance, Neoplasm ; Exons ; Gastrectomy ; methods ; Gastrointestinal Neoplasms ; drug therapy ; metabolism ; pathology ; surgery ; Gastrointestinal Stromal Tumors ; drug therapy ; metabolism ; pathology ; surgery ; Humans ; Imatinib Mesylate ; Liver Neoplasms ; drug therapy ; secondary ; Male ; Piperazines ; therapeutic use ; Point Mutation ; Proto-Oncogene Proteins c-kit ; genetics ; metabolism ; Pyrimidines ; therapeutic use

Objective To establish the 2 day-old SD rats model of periventricular leukomalacia(PVL).Methods Sixty-five healthy 2 day-old SD rats were randomly divided into 3 experimental PVL groups and 3 control groups.The experimental PVL groups were subjected to right carotid ligation(RCL),and then they were suffered from hypoxia by 6% oxygen and 94% nitrogen for 4 hours.Meanwhile sham surgeries were performed on control groups without exposed to hypoxia.Light and electronic microscopy were used to observe brain pathological changes.Immunohistochemistry methods were used to detect the distribution and expression of glial fibrillary acidic protein(GFAP),?-amyloid precursor protein(?-APP),myelin basie protein(MBP) and O4 of brain at 72 hours post-operation.Han-(ging) test,inclined plane test,open field test and cylinder test were performed on the rats 28 days post-operation.Results 1.In the PVL groups,light and electronic microscopy showed that tissue necrosis was observed in the periventricular white matter area at early stage,and at later stage right ventricular dilation,decrease of the corpus callosum area and loss of medullary sheath were detected.The morphometrical analysis showed that GFAP and ?-APP integrated optical density(A) of PVL group was increased,and mean diameter of GFAP-immunoreactive cells was also increased in PVL group,while MBP A of PVL group was decreased compared with contral group.The density of O4-immunoreactive abnormal cells was dramatically increased in PVL group.The outcomes of neurobehavioral tests of PVL group were greatly abnormal compared with control group.Conclusion The changes in 2-day-old SD rats,RCL-hypoxia model are accor-(ded) with the pathology and behavior characeriatis of PVL.

Objective The construction of suicide plasmid vector could be used to make mutation of pgm gene which attenuates the virulent of Brucella melitensis strain 16, the research may lay a foundation for the development of novel live attenuated vaccines. Methods Sucrose sensitive gene as forward screening sign and fusion sequences of kanamycin resistance gene were constructed based on plasmid pucl9; pucS1.6K suicide plasmid vector was established by modifying pgm gene with fusion sequences of kanamycin resistance gene (insertion mutation); pgm gene mutation of Brucella melitensis strain 16 was obtained by electro transformation and mutation was confirmed by PCR amplification. Results The results showed that the identified Brucella melitensis strain 16 pgm gene was inactivated after insertion of kanamycin resistance gene, and the mutant pgm gene DNA fragment length was approximately 3525 bp, in line with expectations, Brucella pgm gene mutant melitensis strain 16 was successfully constructed. Conclusions The construction of suicide plasmid vector and precise mutation of Brucella melitensis strain 16 is successful, the study is not only provided an effective technology platform for constructing mutants of Brucella but also lays a foundation for the development of novel live attenuated vaccines.

Objective To observe the effect of different thyroid hormone level on the expression of synaptotagmin Ⅰ(Syt Ⅰ) in adult rat hippocampus. Methods All 28 adult male SD rats were assigned randomly into hypothyroid, hyperthyroid and control group, hypothyroid group was established by daily intraperitoneal injections with propylthiou raci(PTU, 10.0 mg/kg body weight) for 6 weeks and hyperthyroid group with L-Thyroxine (L-T4, 0.5 mg/kg body weight) for 3 weeks. Radioimmunity method was used to assay the levels of serum T3 and T4, immunohistochemical S-P technology to assay the levels of Syt Ⅰ protein in hippoeampus CA1, CA3 and dentate gyrus (DG). The layers analyzed in the different subfields include the polymorphic cell layer(the stratum oriens, SO), pyramidal cell layer(PCL), stratum radiatum (SR), lacunosum-molecular layer (SLM) in CA1 and CA3, granular cell layer(GL) and molecular layer(ML) in DG. Results The levels of serum T3 and T4[(0.34±0.12), (41.03± 11.37)nmol/L]in the hypothyroid rats were significantly lower than those in the control group[(0.65±0.15), (55.20±10.68)nmol/L, P < 0.01 or < 0.05], and the positive granule of Syt Ⅰ was significantly lower in PCL and SR of CA1 and CA3, GL of DG. The average optical value responsible for Syt Ⅰ immunoreactivity was obviously reduced in SO(0.048±0.007), PCL(0.299±0.035), SR(0.042±0.007), SLM(0.038±0.006) of CA1, PCL(0.085± 0.019), SR(0.040±0.011), SLM (0.038±0.006) of CA3, GL (0.076±0.019) of DG than normal controls (0.068± 0.014, 0.376±0.053, 0.053±0.008,0.056±0.009,0.118±0.026,0.052±0.010,0.053±0.009,0.099±0.015; P< 0.01 or < 0.05). Serum T3 and T4 levels [(1.43±0.30), (157.18±19.95)nmol/L]of hyperthyroid rats were significantly higher than those of control group(P < 0.01). The value was reduced in PCL(0.322±0.050), SR(0.039±0.006), SLM (0.042±0.006) of CA1, PCL(0.098±0.034), SR(0.046±0.013), SLM(0.046±0.010) of CA3 and GL(0.085± 0.024), ML (0.042±0.009) of DG (P < 0.05 or < 0.01). Conclusion Adult-onset of hypothyroidism and hyperthyroidism can reversibly decrease the expression of Syt Ⅰ in CA1, CA3 and DG regions of hippocampus.

The clinical tumor therapy was greatly challenged due to the complex characteristics of tumor microenvironment, however, which also provide arena for novel therapeutic strategies. In this study, poly(2-ethyl-2-oxazoline)-poly(lactic acid)-SS-poly(β-amino ester (PEOz-PLA-SS-PBAE) triblock copolymers with pH and GSH double response were synthesized, polymer micelles were prepared by thin film hydration method for loading of silybin to improve its antitumor activity. The critical micelle concentration was determined by pyrene fluorescence method as 1.8 μg·mL^-1. The particle size was 155.30 ± 1.80 nm as determined by dynamic light scattering, with polydispersity index of 0.168 ± 0.004. The drug loading and entrapment efficiency of the micelles were determined by HPLC as (5.48 ± 0.04)% and (68.52 ± 0.48)%, respectively. The in vitro drug release profiles showed that the micelles have low pH sensitivity and high GSH responsiveness, and exhibited sustained release profiles. The good biocompatibility of the material was proved by measuring the hemolysis rate and cytotoxicity of the blank micelle. The cytotoxicity and apoptosis rate of tumor cells showed that the drug loaded PEOz-PLA-SS-PBAE micelles had significant inhibitory effect and apoptosis-inducing effect on MDA-MB-231 cells. The results of wounding healing assay and Transwell invasion test showed that the drug loaded PEOz-PLA-SS-PBAE micelles could significantly inhibit the metastasis of MDA-MB-231 cells. The PEOz-PLA-SS-PBAE drug-loaded micelles prepared in this study have good inhibitory effect on tumor growth and anti-tumor metastasis in vitro, which lays the foundation for the further application of silybin.

OBJECTIVEWhite matter damage (WMD) in preterm infants is a well-recognized serious complication of prematurity. The collapse of cell skeleton of growth cone after hypoxia-ischemia (HI) is considered as the basic neuropathologic change of the long-term residuals of premature white matter damage. F-actin is the major component of cell skeleton and maintains the normal form of cells, its function and potential mechanism of WMD have not been reported. In this study, changes of F-actin and its influencing factor RhoA were investigated.

METHODSTotally 184 Sprague-Dawley (SD) rats (age 2 days, body weight 6 to 8 grams) were randomly divided into 14 groups: 7 different time WMD groups (HI 12 h, 24 h, 48 h, 72 h, 7 d, 14 d, 28 d) and 7 corresponding control groups. The 2 day-old SD rats were subjected to ligation of right carotid artery (ischemia), and then they were put into a box full with 6% oxygen and 94% nitrogen for 4 hours (hypoxia). The light microscopy was used to observe the brain pathological changes and the electron microscopy was used to detect the brain ultrastructural changes after hypoxia and ischemia. Eighty SD rats were used for flurescent-immunohistochemical method to detect the distribution of F-actin in cell membrane and cytoplasm of both WMD groups and the control groups at 12 h, 24 h, 48 h, 72 h, 7 d after HI respectively. The distribution of F-actin was reflected by the percentage of non-integrity cells. Another 80 SD rats were used for real time RT-PCR to detect the expression of RhoAmRNA in the white matter tissue of both WMD groups (HI 12 h, 24 h, 48 h, 72 h, 7 d) and the control groups.

RESULTS(1) Necrosis of lateral ventricle tissue was observed by 72 h after HI. Dilatation of ventricle and formation of capsular space beneath white matter had been observed by 14 d after HI. (2) Disregulation, pyknosis, mitochondrion swelling and chromatin agglutination were observed in WMD groups. The maldevelopment of myelins in WMD groups was detected at 1 h after HI. (3) The fluorescent stains decreased on cellular membrane, but increased in cytoplasm with time. The percentage of non-integrity cells was significantly higher (P < 0.05) in HI groups (0.32 +/- 0.04, 0.43 +/- 0.04, 0.56 +/- 0.03, 0.65 +/- 0.04, 0.87 +/- 0.03) than the controls (0.02 +/- 0.01, 0.02 +/- 0.01, 0.01 +/- 0.01, 0.02 +/- 0.01, 0.02 +/- 0.01). (4) The expression of RhoA mRNA was significantly increased (P < 0.05) in HI groups (1.205, 2.415, 4.830, 1.500) in the white matter tissue compared with the controls (0.300, 0.375, 0.375, 0.530) at 12 h, 24 h, 48 h, 72 h after HI. The expression of RhoA mRNA reached the peak value at HI 48 h, and then gradually decreased. The expression of RhoA mRNA at HI 7 d in WMD group (0.500) was not significantly different from the control (P > 0.05).

CONCLUSION(1) The pathological and ultrastructural changes of white matter in WMD groups after HI suggest that the WMD model was successfully set up in premature 2 days SD rats. (2) F-actin is redistributed within cells after HI: expression in membrane is decreased and expression in plasma was increased. The redistribution possibly results in the collapse and retraction of cells. (3) The expression of RhoA mRNA is increased significantly after HI, which may lead to the redistribution of F-actin. (4) The increase of the expression of RhoA mRNA is not persistent, but the redistribution of F-actin is continued, which suggests that RhoA may not be the only factor affecting the redistribution of F-actin.

Actins ; genetics ; metabolism ; Animals ; Humans ; Hypoxia-Ischemia, Brain ; metabolism ; Infant ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; rhoA GTP-Binding Protein ; genetics ; metabolism

OBJECTIVERecent studies have indicated that the signal pathway of NgR-P75NTR- RhoA plays a key role in nerve injury and remodeling, but its exact mechanism and the role of the downstream molecule RhoA regulated by P75NTR remain unclear in hypoxia-ischemia (HI) neonatal animals. The present study was designed to assess the expression of P75NTR protein and RhoA mRNA in neonatal white matter and to investigate their relationship in newborn rats with white matter damage (WMD).

METHODSThe rat WMD model was established by the ligation of right common carotid artery, followed by 6% hypoxia exposure for 4 hrs. The control group was sham-operated, without HI treatment. The histological changes of brain tissue were observed under light and electron microscopes. Expression of P75NTR protein and RhoA mRNA in the brain white matter after 12, 24, 48 and 72 hrs and 7 days of HI were detected by RT-PCR and immunohistochemistry, respectively.

RESULTSPeriventricular white matter damage was observed by 48 hrs of HI. Expression of P75NTR protein increased in the striatum and callosum zones at 12 hrs, peaked at 48 hrs, and remained at a higher level than control until 72 hrs of HI in the WMD group (P < 0.01). After 7 days of HI expression of P75NTR protein was no longer statistically different from controls. The RhoA mRNA was higher in the WMD group for the first 72 hrs and then declined to control values.

CONCLUSIONSIncreased P75NTR protein might mediate apoptosis of nerve cells and inhibit the regeneration of neuron axons. The subsequent decline back to control value may be correlated with the aggregation of necrosis of nerve cells after HI. The patterns of RhoA mRNA expression were consistent with those of P75NTR protein, suggesting that the increased P75NTR level may promote RhoA mRNA expression.

Animals ; Animals, Newborn ; Brain ; pathology ; ultrastructure ; Female ; Hypoxia-Ischemia, Brain ; metabolism ; pathology ; Immunohistochemistry ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptor, Nerve Growth Factor ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; rhoA GTP-Binding Protein ; genetics

OBJECTIVETo study the expression of the AMPA receptor subunit glutamate receptor 2 (GluR2) and the cellular free calcium concentration in the white matter of neonatal rats with periventricular leukomalacia (PVL) and their roles in the pathogenesis of PVL.

METHODSA PVL model was prepared by unilateral carotid artery ligation (UCL) followed by exposure to 6% oxygen for 4 hrs in 2-day-old rats. The neonatal rats performed a sham operation, without hypoxia-ischemia (HI), were used as the control group. At 12, 24, 48 and 72 hrs of HI, the expressions of GluR2 mRNA and protein in the white matter were detected using real time quantitative PCR and Western blot respectively. Spectrophotofluorimetry and Fura 2/AM were used to detect the cellular free calcium concentration.

RESULTSThe expressions of GluR2 mRNA and protein in the white matter were significantly reduced in the PVL group at 24 hrs of HI, and remained at lower expressions until 72 hrs of HI compared with the control group (P < 0.05). The cellular free calcium concentrations increased significantly in the PVL group at 12 hrs of HI, and remained at higher levels until 72 hrs of HI compared with the control group (P < 0.05).

CONCLUSIONSThe expressions of GluR2 mRNA and protein in the white matter decreased whereas the cellular free calcium concentration increased in neonatal rats with PVL. The decreased expression of GluR2 might lead to the overloading of cellular calcium in the white matter, which may cause neuronal damage and death.

Animals ; Blotting, Western ; Calcium ; physiology ; Humans ; Infant, Newborn ; Leukomalacia, Periventricular ; etiology ; Oligodendroglia ; pathology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptors, AMPA ; genetics ; physiology ; Reverse Transcriptase Polymerase Chain Reaction