BACKGROUND: Poly (lactic-co-glycolic-acid) (PLGA)/nano-hydroxyapatite (nHA) composite microspheres may continuously release drug in phosphate buffer solution in vitro.OBJECTIVE: To prepare 5-fluorouracil (5-Fu)-loaded PLGA/nHA microspheres, and research the effect of nHA on drug loading,encapsulation efficiency and in vitro release.DESIGN, TIME AND SETTING: An in vitro materials observation was performed at Laboratory of College of Materials Science and Engineering, South China University of Technology between February and July 2009.MATERIALS: PLGA was provided by Jinan Daigang Biomaterial Co., Ltd.; nHA by Key Lab for Special Functional Materials,Ministry of Education; 5-Fu by Shanghai Kaiyang Biomaterial Co., Ltd.METHODS: 5-Fu, a water-soluble anti-cancer drug, was used as model drug, and was firstly adsorbed by nHA and coated with biodegradable and blocompatible materials of PLGA so as to prepare PLGA/nHA-5-Fu composite microspheres by a single-emulsion solvent evaporation method (S/O/W). nHA and drug-loaded nHA were analyzed by transmission electron microscope (TEM), scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR). Drug loading and encapsulation efficiency as well as in vitro release of microspheres were studied with SEM, laser particle size analyzer, and UV-spectrophotometer.MAIN OUTCOME MEASURES: Interaction between nHA and 5-Fu; drug loading, encapsulation efficiency, and in vitro release of Microspheres RESULTS: FTIR showed that nHA had a strong adsorption with 5-Fu. Drug loading and encapsulation efficiency of PLGA/nHA-5-Fu composite microspheres were 3.83% and 86.78%, respectively, which were significantly greater than PLGA-5-Fu microspheres. After initial burst, composite microspheres released more slowly than PLGA microspheres alone. At day 27, the cumulative release rate of composite microspheres and PLGA microspheres alone were 84.87% and 99.87%,respectively.CONCLUSION: Because nHA has a strong adsorption with 5-Fu, PLGA/nHA-5-Fu composite microspheres compared to PLGA-5-Fu microspheres alone enhances drug loading and encapsulation efficiency, and has a better drug delivery effect.

Cerebrograph imaging system is a medical imaging device which is used to diagnose cere- brovascular disease and investigate the function of cerebrum.This system can analyse quantitatively regional Cerebral Blood Flow(rCBF)and map it.Besides that,it can also record and analyse quantitatively electroen- cephalography(EEG)andmap topographical EEG.The measurement of cerebellum-brain stem-cerebral cor- tex is realized and a map is also given.This system first conjugates the technique of nuclear medicine imag- ing with that of electrophysiology.It provides doctors with synthetic information about CBF and the function of cerebrum in the manner of colour rCBF map,topographical EEG and quantitative data.These informa- tion are very important to the diagnosis and the research of cerebropathy,and especially have significant val- ue to earlier diagnosis of cerebrovascular disease.

Apoptosis is a physiologically essential mechanism of cell and plays an important role in reducing the development and progression of tumors. The appealing strategy for cancer therapy is to target the lesions that induce apoptosis in cancer cells. Survivin, the smallest member of the mammalian inhibitors of the apoptosis protein family, is upregulated in various malignancies to protect cells from apoptosis. Survivin knockdown could induce cancer cell apoptosis and inhibit tumor-angiogenesis. Survivin expression would be silenced by microRNA (miRNA)-mediated RNA interference. However, noninvasive and tissue-specific gene delivery techniques remain absent recently and the utilizations of miRNA expression vectors have been limited by inefficient delivery technique, especially in vivo. On the other hand, safe and promising technologies of gene transfection would be valuable in clinical gene therapy. Successful treatment of gene transfer method would lead to a new and readily available approach in the anticancer research. Sonoporation is an alternative technique of gene delivery that uses ultrasound targeted microbubble destruction to create pores in the cell membrane. Based on our previous studies, in this article, we postulated that the transfection of miRNA could be mediated by the combination of sonoporation and polyethylenimine (PEI) which was one of the most effective poly-cationic gene vectors and enhance the endocytosis of plasmids DNA and hypothesized that the gene silencing and apoptosis induction with miRNA targeting human Survivin would be improved by this novel technique. In our opinion, this novel combination of sonoporation and PEI could enhance targeted gene delivery effectively and might be a feasible, novel candidate for gene therapy.
Genetic Therapy ; methods ; Humans ; Inhibitor of Apoptosis Proteins ; genetics ; MicroRNAs ; genetics ; Neoplasms ; therapy ; Polyethyleneimine ; chemistry ; Transfection ; methods

OBJECTIVETo investigate the mutation characteristics of spastin gene in Chinese patients with hereditary spastic paraplegia (HSP) and thus provide a basis for the gene diagnosis of HSP.

METHODSMutation of spastin gene was screened by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) combined with DNA direct sequencing in 31 unrelated affected HSP individuals in China, of whom 22 were from autosomal dominant families and 9 were sporadic HSP patients. Co-segregation analysis was carried out after the finding of abnormal SSCP bands.

RESULTSSix cases were found to have abnormal SCP bands, and among them, two missense mutations (T1258A, A1293G in exon 8) and one deletion mutation (1667delACT or 1668delCTA or 1669delTAC in exon 14) were found and all of them were not reported previously. They were all co-segregated with the disease and were localized within the functional domain of spastin gene. Besides, T1258A was seen in two unrelated families.

CONCLUSIONThe mutation rate (18.2%) in autosomal dominant HSP in Chinese patients is comparatively low. Point mutation is the major mutation type and exon 8 may be the mutation hot spot.

Adenosine Triphosphatases ; genetics ; Asian Continental Ancestry Group ; genetics ; China ; Exons ; Female ; Humans ; Introns ; Male ; Mutation ; Mutation, Missense ; Pedigree ; Spastic Paraplegia, Hereditary ; genetics ; Spastin

The aim of this study was to explore the protective effect of basic fibroblast growth factor (bFGF) on brain injury following global ischemia reperfusion and its mechanisms. Brain injury following global ischemia was induced by four vessels occlusion and systemic hypotension. Twenty-four rabbits were randomized into three groups: group A, only dissection of vessels; group B, intravenous infusion of normal saline after reperfusion for 6 h; group C, 30 microg/kg bFGF injected intravenously at the onset of reperfusion, then infused with 10 microg/(kg.h) for 6 h. Serum neuron specific enolase (NSE), S-100B, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-8 (IL-8) were measured before ischemia, 30 min after ischemia, 0.5, 1, 3, 6 h after reperfusion. Brain water content was determined and cerebral histopathological damages were compared. NSE and S-100B were increased 1 h after reperfusion and reached their peaks 6 h after reperfusion, but were much higher in group B than those in group C 3, 6 h after reperfusion. In groups B and C, TNF-alpha was increased after ischemia and IL-1 and IL-8 were increased significantly 0.5 h after reperfusion, then reached their peaks 6 h, 3 h, 6 h after reperfusion respectively. TNF-alpha and IL-8 at the time points of 1 h and 3 h and IL-1 at 3 h and 6 h in group C were correspondingly lower than those in group B. These indices in group A were nearly unchanged. There were less severe cerebral histopathological damages in group C compared with group B, but no difference in brain water content. It could be concluded that bFGF alleviates brain injury following global ischemia and reperfusion by down-regulating expression of inflammatory factors and inhibiting their activities.
Animals ; Brain ; drug effects ; pathology ; Brain Ischemia ; drug therapy ; pathology ; Fibroblast Growth Factor 2 ; administration & dosage ; Infusions, Intravenous ; Rabbits ; Reperfusion Injury ; drug therapy ; pathology ; Treatment Outcome

This article reports two cases of childhood-onset nemaline myopathy diagnosed by muscle pathology and genetic diagnosis. The two patients had onset in early childhood, with muscle weakness as the first manifestation, as well as long disease duration and slow progression. Gomori staining and hematoxylin-eosin staining showed red-stained rods in the sarcoplasmic cytoplasm and sarcolemma under a light microscope. Electron microscopy showed that the dense nemaline rods were located under the muscle fiber sarcolemma and parallel to the long axis of the muscle fibers, and some muscle fiber myofilaments were dissolved and necrotic. Gene testing found that one of the two patients had heterozygous mutation (c.1013A>C) in the ACTA1 gene, and the other had compound heterozygous mutation (c.18676C>T and c.9812C>A) in the NEB gene. The two mutations were more common in nemaline myopathy. Nemaline myopathy is a recessive or dominant inheritance myopathy, in which the nemaline rod in the cytoplasm of myocytes is a characteristic muscle pathological change. Pathological and genetic diagnosis is the gold standard for diagnosis of nemaline myopathy.

Adult ; Asian Continental Ancestry Group ; DNA Mutational Analysis ; Female ; Humans ; Male ; Middle Aged ; Parkinsonian Disorders ; genetics ; Pedigree ; Proton-Translocating ATPases ; genetics ; Young Adult

OBJECTIVETo study the effect of fleroxacin (FLRX) on biological properties of Bloom (BLM) helicase catalytic core (BLM642-1290 helicase) in vitro and the molecular mechanism of interaction between the two molecules.

METHODSDNA-binding and unwinding activities of BLM642-1290 helicase were assayed by fluorescence polarization and gel retardation assay under conditions that the helicase was subjected to different concentrations of FLRX. Effect of FLRX on helicase ATPase activity was analyzed by phosphorus-free assay based on a colorimetric estimation of ATP hydrolysis-produced inorganic phosphate. Molecular mechanism of interaction between the two molecules was assayed by ultraviolet and fluorescence spectra.

RESULTSThe DNA unwinding and ATPase activities of BLM642-1290 helicase were inhibited whereas the DNA-binding activity was promoted in vitro. A BLM-FLRX complex was formed through one binding site, electrostatic and hydrophobic interaction force. Moreover, the intrinsic fluorescence of the helicase was quenched by FLRX as a result of non-radioactive energy transfer. The biological activity of helicase was affected by FLRX, which may be through an allosteric mechanism and stabilization of enzyme conformation in low helicase activity state, disruption of the coupling of ATP hydrolysis to unwinding, and blocking helicase translocation on DNA strands.

CONCLUSIONFLRX may affect the biological activities and conformation of BLM642-1290 helicase, and DNA helicase may be used as a promising drug target for some diseases.

DNA ; metabolism ; Fleroxacin ; pharmacology ; Nucleic Acid Synthesis Inhibitors ; pharmacology ; RecQ Helicases ; antagonists & inhibitors ; metabolism ; Spectrometry, Fluorescence ; Spectrophotometry, Ultraviolet

OBJECTIVETo explore the clinical value of contrast-enhanced ultrasound (CEUS) in the diagnosis of Budd-Chiari syndrome with inferior vena cava (IVC) obstruction.

METHODA total of 38 patients with Budd-Chiari syndrome with IVC obstruction were examined by CEUS before and after vascular interventional management, and the results were compared with angiographic findings.

RESULTSThe location and degree of IVC obstruction were clearly showed on CEUS. Enhancement was found in the occlusion site, and blood flow was narrowed at the stenosis site. The arrival time was earlier after treatment in the IVC obstruction, and it was positively correlated with the pressure of IVC( P< 0.05).

CONCLUSIONThe location and type of the occlusion and stenosis in IVC can be accurately determined by CEUS. Therefore, CEUS can provide useful information for the selection of surgical procedures and post-operative effectiveness.

Adolescent ; Adult ; Budd-Chiari Syndrome ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Ultrasonography ; Vena Cava, Inferior ; diagnostic imaging ; Young Adult

OBJECTIVETo investigate the role of α-enolase (ENO1) in regulating glucose metabolism and cell growth in human glioma cells.

METHODSGlucose uptake and lactate generation were assessed to evaluate the changes in glucose metabolism in human glioma U251 cells with small interfering RNA (siRNA)-mediated ENO1 knockdown. MTT assay and 5-ethynyl-2'-deoxyuridine (EdU) staining were used to examine the cell growth and cell cycle changes following siRNA transfection of the cells.

RESULTSTransfection of U251 cells with siRNA-ENO1 markedly reduced glucose uptake (P=0.023) and lactate generation (P=0.007) in the cells and resulted in significant suppression of cell proliferation (*P<0.05) since the second day following the transfection. Transfection with siRNA-ENO1 also obviously suppressed cell cycle G1/S transition in the cells (P=0.0425). The expressions of HK2 and LDHA, the marker genes for glucose metabolism, were significantly down-regulated in the cells with siRNA-mediated ENO1 knockdown.

CONCLUSIONENO1 as a potential oncogene promotes glioma cell growth by positively modulating glucose metabolism.