The role of very low density lipoprotein receptor (LVLDR) in the process of foam cell formation was investigated. After the primary cultured mouse peritoneal macrophages were incubated with VLDL, β-VLDL or low density lipoprotein (LDL), respectively for 24 h and 48 h, foam cells formation was identified by oil red O staining and cellular contents of triglyceride (TG) and total cholesterol (TC) were determined. The mRNA levels of LDLR, LDLR related protein (LRP) and VLDLR were detected by semi-quantitative RT-PCR. The results demonstrated that VLDL, β-VLDL and LDL could increase the contents of TG and TC in macrophages. Cells treated with VLDL or β-VLDL showed markedly increased expression of VLDLR and decreased expression of LDLR, whereas LRP was up-regulated slightly. For identifying the effect of VLDL receptor on cellular lipid accumulation, ldl-A7-VR cells, which expresses VLDLR and trace amount of LRP without functional LDLR, was used to incubate with lipoproteins for further examination. The results elucidated that the uptake of triglyceride-rich lipoprotein mediated by VLDLR plays an important role in accumulation of lipid and the formation of foam cells.

In order to study the effect of nitric oxide (NO) on the expression of hypoxia-inducible factor-1 alpha (HIF-1α) mRNA in hypoxic pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic hypoxic group and hypoxia plus L-argine (L-Arg) group. The animal model of HPH was developed. The mean pulmonary arterial pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF-1α mRNA expression levels were detected by in situ hybridization (ISH) and semiquantitative RT-PCR. It was found that after 14 days hypoxia, the mPAP in normoxic control group (17.6±2.7 mmHg,l mmHg=0.133 kPa) was significantly lower than that in chronic hypoxic group (35.8 ±6.1 mmHg,t=0.2918,P<0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L-argine group (24.4±3.8 mmHg,t=0.2563,P<0.05). ISH showed that the expression of HIF-1α mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group (0.1076±0.0205) was markedly weaker than that in chronic hypoxic group (0.3317±0.0683,t=3.125,P<0.05) and that in chronic hypoxic group was stronger than that in hypoxia plus L-argine group (0.1928±0.0381,t=2.844,P<0.05). RT-PCR showed that the content of HIF-1α mRNA in chronic hypoxic group (2.5395±0.6449) was 2.16 times and 1.75 times higher than that in normoxic control group (1.1781±0.3628) and hypoxia plus L-argine group (1.4511±0.3981), respectively. It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF-1α mRNA, which may be one of the mechanisms through which NO affects the pathogenesis of HPH.

In order to investigate the effect of nuclear factor-kappa B (NF-κB) on vascular endothelial growth factor (VEGF) mRNA expression of human pulmonary artery smooth muscle cells (HPASMCs) in hypoxia, the cultured HPASMCsin vitro were stimulated with pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB. The NF-κB p65 nuclei positive expression was detected by immunocytochemical technique. The IκBα protein expression was measured by Western blot. RT-PCR was used to detect the VEGF mRNA expression of HPASMCs. The results showed that no significant change was observed in the NF-κB p65 nuclei positive expression of HPASMCs during 6 h−24 h in normoxia, but the levels of NF-κB p65 nuclei positive expression of cultured HPASMCs were significantly increased in hypoxia groups as compared with those in all normoxia groups (P<0.05). The IκBα protein expression of cultured HPASMCs showed no significant change during 6 h−24 h in normoxia, but significantly decreased in hypoxia as comapred with that in normoxia groups (P<0.05). PDTC (1 to 100 μmol/L) could inhibit the VEGF mRNA expression of HPASMCs in a concentration-dependent manner in hypoxia. In conclusion, NF-κB can be partly translocation activated from cytoplasm into nuclei in the cultured HPASMCs under hypoxia. The inhibition of NF-κB activation can decrease the VEGF mRNA expression. It is suggested that the activation of NF-κB is involved in the VEGF mRNA expression of HPASMCs under hypoxia.

In order to investigate the effect of nuclear factor-κB (NF-κB) on airway remodeling in asthmatic rats. 18 Wistar rats were divided into three groups: asthmatic group: pyrrolidine dithiocarbamate (PDTC) group, in which rats were injected intraperitoneally with NF-κB specific inhibitor PDTC (100 mg/kg) before ovalbumin (OVA) challenge; control group. The NF-κB activity and the expression of inhibitory protein κBα (I-κBα) in airway were detected by electrophoretic mobility shift assay (EMSA). Western blot and immunohistochemistry respectively. The infiltration of inflammatory cells, the number of Goblet cells, the area of collagen and smooth muscle in airway were measured by means of image analysis system. The results showed that with the up-regulation of airway NF-κB activity in asthmatic group, the number of goblet cells (3.08±0.86/100 μm basement membrane (BM)), the area of collagen (24.71±4.24 μm²/μm BM) and smooth muscle (13.81±2.11 μm²/μmBM) in airway were significantly increased (P<0.05) as compared with control group (0.14±0.05/100μmBM. 14.31±3.16 μm²/μm BM and 7.67±2.35 μm²/μm BM respectively) and PDTC group (0.33±0.14/100 μmBM, 18.16±2.85 μm²/μm BM and 8.95±2.16 μm²/μm BM respectively). However, there was no significant difference between PDTC group and control group (P>0.05). It was concluded that the activity of NF-κB is increased in airway of asthmatic rats. Inhibition of NF-κB, activation can attenuate constructional changes in asthma airway, suggesting NF-κB may contribute to asthmatic airway remodeling.

Whether melatonin not only inhibits the growth of H22 hepatocarcinoma cells but also induces apoptosis in vitro was assessed. The anti-proliferative effects of melatonin on tumor cells was observed by MTT assay and tumor cells growth curve assay. And the apoptosis of the cells was studied by acridine orange fluorescence assay and flow cytometry. The cell cycle of the tumor cells was also observed by flow cytometry. It was found that melatonin could significantly inhibit the growth of H22 hepatocarcinoma cells. Incubated with melatonin, chromatin condensation of the tumor cells was observed by fluorescence microscopy. Compared with control, the percentage of appoptotic cells was increased, and the proportion of G₀/S increased but that of G₂/M decreased. It was suggested that melationin could directly inhibit the growth of H22 hepatocarcinoma cells by inducing apoptosis and extending the length of cell cycle of the tumor cells.

The gene encoding urease subunit A (ureA) of Helicobacter pylori (H. pylori) was cloned from H. pylori isolate by polymerase chain reaction (PCR). Sterile distilled water instead of DNA served as negative control. The nucleotide sequence of the amplified product was determined. Homologous analysis of the ureA against that reported by Clayton CL and the GenBank and SwissProt databases were performed with the BLAST program at the Genome Net through the Internet. 0.8 kb PCR product was amplified from all H. pylori clinical isolators. The nucleotide sequence of the ureA was determined. The nucleotide sequence of the ureA began with ATG as the initiation codon and terminated in TAA as stop codon. The coding regions had a 44% G+C content. The DNA sequence was 98% homologous to that reported by Clayton CL (688 out of 702 residues were identical). The derived amino-acid sequences of the ureA were 99% homologous to that reported by Clayton CL (232 out of 234 residues were identical). The nucleotide sequence and the predicted protein showed significant homology to ureA of H. pylori in the NCBI Entrez database.

A protocol for enrichment and adsorption of karyocyte from whole blood by using magnetic nanometer beads as solid-phase absorbents was presented. The PCR amplification could be accomplished by using the nanobeads with karyocyte as template directly and the PCR products were applied on an oligonucleotide array to do gene typing. The HLA-A PCR amplification system and a small HLA-A oligonucleotide microarray were applied as the platform and an experiment protocol of separating karyocyte from whole blood using the magnetic nanometer beads (Fe₂O₃) were set up. The experimental conditions were also discussed. It showed that pH level of PBS eluent, Taq enzyme quantity and fragment length of products could influent the amplification results, and the magnetic nano-beads could succeed in sample preparation in microarray to provide a promising way in automatic detection and lab-on-a-chip.

In order to investigate whether polymorphism in gene for heat shock protein 70 (HSP70) has any bearing on individual susceptibility to the development of chronic obstructive pulmonary disease (COPD), the geotypes of 88 patients with COPD and 87 healthy smoking control subjects were tested by polymerase chain reaction followed by restriction fragment polymorphism analysis for HSP70 gene. In COPD group, HSP70-1 genotype A/A, A/B and B/B was 59. 1%, 35.2% and 5.7%, HSP70-2 genotype A/A, A/B and B/B was 26.1%, 54.6% and 19.3%, and HSP70-hom genotype A/A, A/B and B/B was 70.4%, 27.3% and 2.3% respectively. In the control group, it was 60.9%, 27.5% and 3.5%, 20.7%, 56.3% and 23.0%, and 54.0%, 42.5% and 3.5%, respectively. The frequency of polymorphic genetypes showed no difference between the COPD group and the control group (P>0.05). It was suggested that geneic polymorphism in HSP70 is not associated with development of COPD in Han nationality of China.

In order to investigate the changes in the expression of extracellular signal-regulated kinase (ERK1/ERK2) and angiotensin-converting enzyme (ACE) in the patients with atrial fibrillation (AF), 52 patients with rheumatic heart diseases were examined. Nineteen patients had chronic persistent AF (AF>-6 months, CAF), 12 patients had paroxymal AF (PAF) and 21 patients had no history of AF. The ERK expression was detected at the mRNA level by reverse transcription polymerase chain reaction, at the protein level by Western blotting and at atrial tissue level by immunohistochemistry. ERK-activating kinases (MEK1/2) and ACE were determined by Western blotting techniques. The expression of ERK2-mRNA was increased in the patients with CAF (74±19 U vs sinus rhythm: 32±24 U,P<0.05). Activated ERK1/ERK2 and MEK1/2 were increased to more than 150% in the patients with AF compared to those with sinus rhythm. No significant difference between CAF and PAF was found. The expression of ACE was three-fold increased in the patients with CAF compared to those with sinus rhythm. Patients with AF showed an increased expression of ERK1/ERK2 in atrial interstitial cells and marked atrial fibrosis. An ACE-dependent increase in the amounts of activated ERK1/ERK2 in atrial interstitial cells may be one of molecular mechanisms for the development of atrial fibrosis in the patients with AF. These findings may have important impact on the treatment of AF.

The effect of the autonomic nerves on the transmural dispersion of ventricular repolarization in intact canine was investigated. By using the monophasic action potential (MAP) recording technique, monophasic action potentials (MAPs) of the epicardium (Epi), midmyocardium (Mid) and endocardium (Endo) were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free wall in 12 open-chest dogs. MAPD₉₀ and transmural dispersion of repolarization among three myocardial layers as well as the incidence of the EAD before autonomic that the MAPD₉₀ of Epi, Mid and Endo before autonomic nervous stimulation were 278±11 ms, 316±16 ms and 270±12 ms respectively, the MAPD₉₀ of Mid was significantly longer than that of Epi or Endo (P<0.01). MAPD₉₀ of Epi, Mid and Endo were shortened by 19±4 ms, 45±6 ms, 18±3 ms respectively during sympathetic stimulation. Compared with that of the control, the transmural dispersion of repolarization during sympathetic stimulation was shortened from 44±4 ms to 15±3 ms (P<0.01), but early afterdepolarizations were elicited in the Mid of 5 dogs (41%) during sympathetic stimulation. Parasympathetic stimulation did not significantly affect the MAPD₉₀ in the three layers. It is concluded that there is the transmural dispersion of ventricular repolarization in intact canine. Sympathetic stimulation can reduce transmural dispersion of repolarization, but it can produce early afterdepolarizations in the Mid. Parasympathetic stimulation does not significantly affect the transmural dispersion of ventricular repolarization.

The effects of monoterpene perilly alcohol (POH) alone or in combination with STI571 on the proliferation and apoptosis of the cell line K562 positive for Ber/Abl were investigated. By using cell culture, the effect of the drugs on the proliferation of the cells was studied. TUNEL and flow cytometry assay of FITC-Annexin V and PI labeled cells were applied to detect the effects of the drugs on the apoptosis of the cells. The results showed that at 36 h, IC50 of POH on K562 positive for Bcr/Abl and HL-60 negative for Bcr/Abl were 81.0±11.3 μmol/L and 113.6±23.4 μmol/L respectively (P>0.05). POH could inhibit the proliferation of K562 in a time- and dose-dependent manner with the inhibitory rate of 100 μmol/L POH on K562 cells at 36 h being (53.2±3.65)%. K562 cells were more sensitive to STI571 than POH. IC50 of STI571 on K562 cells in 36 h was (0.256±0.054) μmol/L. In a time- and dose-dependent manner, POH induced the apoptosis of K562 cells with the percentage of apoptotic cells by 100 μmol/L POH at 40 h being (21.0±3.3) %. Both 100 μmol/L POH and 0.2 μmol/L STI571 had the same inhibitory effects on the K562 cells at 36 h. But at 12 and 24 h, the inhibitory rate of POH was significantly higher than that of STI571 (P<0.05) and the ability of STI571 inducing apoptosis at 36 h was greater than that of POH. 50 μmol/L, 100 μmol/L and 200 μmol/L POH in combination with 0.2 μmol/L STI571 could obviously increase the inhibitory effects on the cellular proliferation. Combined use of 50 μmol/L, 100 μmol/L, 200 μmol/L with 0.2 μmol/L STI571 could strongly induced apoptosis, especially 200 μmol/L POH in combination with 0.2 μmol/L STI571. It was concluded that the antileukemia effect of POH had no obvious Bcr/Abl positive selectivity. POH can inhibit the proliferation of K562 and induce the apoptosis in a time- and dose-dependent manner. K562 cells were more sensitive to STI571 than POH. POH in combination with STI571 could obviously enhance the abilities of STI571 inhibiting the proliferation and inducing apoptosis of K562 cells.

The effects of a novel immunosuppressive agent FTY720 on proliferation inhibition and apoptosis of acute leukemia cell lines HL-60 and U937, and the role of extracellular regulated protein kinase (ERK) in the course of proliferation inhibition and apoptosis induced by FTY720 were studied. The proliferation inhibition rate of HL-60 and U937 cells by various concentrations of FTY720 was detected by MTT assay. Cell apoptosis was detected by DNA fragment analysis and flow cytometry. The phosphorylated ERK1/2 protein expression was observed by Western blotting. The change of intracellular distribution of ERK1/2 protein was identified by SP immunohistochemical staining. The results showed that FTY720 could inhibit the growth of HL-60 and U937 cells effectively in a dose-dependent manner. After incubation with FTY720 for 24 h, apoptosis was observed in HL-60 and U937 cells. The intracellular expression of phosphorylated ERK1/2 protein was also down-regulated and the distribution of ERK1/2 protein in cell nuclear was reduced during FTY720-induced apoptosis. So, that FTY720 inhibited ERK1/2 phosphorylation might mediate the role of FTY720-induced apoptosis and proliferation inhibition of leukemia cells.

Telomerase activity and the expression of telomerase subunits (for example, telomerase reverse transcriptase and telomerase associated protein 1 and telomerase RNA component) of peripheral white blood cells were detected in the patients with acute myelogenous leukaemia (AML) and the correlation between telomerase activity and the expression of telomerase subunits was observed. In 94 peripheral white blood cells from 18 healthy volunteers and 76 patients with AML, including 31 AML at initial presentation, 24 at relapse and 21 at complete remission, the telomerase activity and telomerase subunits mRNA or RNA were detected by PCR-ELISA and RT-PCR respectively. The results showed that the positive rate of telomerase from patients with AML at initial presentation, at relapse and at complete remission was 74.1%, 79.2% and 4.8% respectively. The positive rate of telomerase reverse transcriptase mRNA from healthy volunteers, AML at initial presentation. AML at relapse and AML at complete remission was 5.6%, 80.6%, 83.3% and 9.5% respectively. The positive rate of telomerase associated protein 1 mRNA and telomerase RNA component in all samples were 100%. It was suggested that the up-regulation of telomerase activity and the expression of telomerase reverse transcriptase is correlated closely with the occurrence and relapse of AML, so telomerase activity and the expression of telomerase reverse transcriptase may be used to estimate the curative effect and predict relapse of AML. Moreover, the upregulation of telomerase activity is correlated with the expression of telomerase reverse transcriptase significantly.

Human acute premyeloid leukemia cell cDNA expression library was constructed to screen acute premyeloid leukemia tumor antigen. Total RNA and purified mRNA were extracted from human premyeloid cell line NB4. First and second strands of cDNA were synthesized by reverse transcription. After blunting, the cDNA fragments were ligated with EcoR I adapters. Then the cDNAs were digested with Xho I, and less than 400 bp cDNA fragment was removed by Sephacryl-S400 spin column, the remaining were ligated with λZAP vector. The recombinants were packagedin vitro, and a small portion of packaged phage was used to infectE. coli XL1-Blue-MRF' for titration. The recombinants were examined by color selection. In order to evaluate the size of cDNA inserts and the diversity of library, the pBK-CMV phagemid was excised from the ZAP express vector by using ExAssist helper phage with XLOLR strain, and then the pBK-CMV phagemid was digested by Xho I and EcoR I. The results showed that the NB4 cell line cDNA library consisting of 1.65×10⁵ recombinant bacteriophages was constructed with the recombinant ratio of 99.6%. The average length of the recombinant exogenous inserts was about 1. 7 kb. It was concluded that the constructed cDNA library are deserved to screen target clones.

To study the growth-inhibitory effects of curcumin on human ovary cancer A2780 cellsin vitro and its molecular mechanisms, the growth inhibition rates of A2780 cancer cells, after being treated with 10 μmol/L–50 μmol/L curcumin for 6–24 h, were examined by MTT method. The morphological changes of cancer cells were observed under inversion microscopy. Cellular apoptotic rates were determined by using TUNEL. The protein expression levels of bcl-2, p53 and MDM2 in cancer cells were examined by SP immunohistochemistry. After being treated by various concentrations of curcumin, the growth of cancer cells was inhibited significantly. Some cancer cells presented characteristic morphological changes of apoptosis. The rates of apoptosis were 6.41%–28.48% (P<0.01). The expression of bcl-2 and p53 was decreased, which depended on the action time (P<0.01). There were no obvious changes in MDM2 expression. It was concluded that curcumin could significantly inhibit the growth of ovary cancer cells. The induction of apoptosis by down-regulating the expression of bcl-2 and p53 was probably one of its molecular mechanisms.

To explore the application of fetal DNA in maternal plasma for noninvasive prenatal diagnosis, the DNA template was extracted by hydroxybenzene-chloroform from 44 maternal (7–41 weeks) plasma. The Fetus-derived Y sequence DYZ-1 gene (149bp) was chosen to be amplified by PCR. The fragment was identified in all the plasma of male bearing pregnant women with the diagnostic accordance rate being 100.00%. Two of the 22 female bearing pregnant women had false positive results. Among the 44 pregnant women, the diagnostic accordance rate was 88.89% at early pregnant stage, 100.00% at medium pregnant stage, and 96.55% at late stage respectively. The final accuracy of 95.45% was obtained in all cases. It was concluded that by means of hydroxybenzene-chloroform extraction the authors of this article promoted the concentration and purity of the DNA template, and diagnosed more accurately. The results showed that free fetal DNA in the maternal plasma could be regarded as the gene resource for noninvasive prenatal diagnosis.

Transforming growth factor-beta (TGF-β) may cause cell cycle arrest, terminal differentiation, or apoptosis in most normal epithelial cells, whereas most malignant cell lines are resistant to TGF-β. Mechanisms of resistance to TGF-β caused by modulation of cell cycle regulators and/or inactivation of components of the TGF-β signaling transduction pathway such as C-myc and Smad4 are not well understood. To investigate the potential association between loss of sensitivity to TGF-β and expression status of transforming growth factor receptor II (TβRII), Smad4, CDC25A and C-myc in 14 cell lines derived from ovarian cancer, the expression levels of these genes were detected by semi-quantitative RT-PCR. Normal ovarian surface tissues were used as controls. The expression of TβR II was detectable in all of 14 cell lines. The expression of Smad4 was decreased in 10 cell lines and 9 cell lines overexpressed CDC25A, as compared to normal controls. CDC25A gene was overexpressed with 88% (8/9) in tumorigenic cell lines as determined by xenografts in nude mice, and only in 20% (1/5) of non-tumorigenic cell lines (P<0.05). C-myc was not overexpressed in any of these cell lines. The loss of sensitivity to TGF-β of cell lines derived from ovarian cancers may be related to a decreased expression of Smad4, which mediates TGF-β induced growth inhibition, and/or an overexpression of CDC25A. This overexpression of CDC25A correlates with increased tumorigenicity of ovarian cancer cell lines. The loss of sensitivity to TGF-β is not associated with a lack of TβRII.

A new method for noninvasive prenatal diagnosis of fetal sex was developed by using single-cell PEP-PCR techniques. Micromamipulation techniques were used to obtain single fetal cells from 273 maternal blood samples. The genome of single cells was preamplified by PEP and SRY genes were analyzed by PCR method. The SRY genes of 149 samples were detected by the new method among 153 samples carrying male fetus, while 119 out of 120 samples carrying female fetus were proved negative for SRY genes. The sensitivity and specificity of the new method were 97.39% and 99.17% respectively and the correct rate was 98.17%. The new method has the advantage of high sensitivity and specificity in noninvasive prenatal diagnosis of fetal sex and provides the basis of other researches such as sex-linked inherited diseases.

In order to investigate the correlation between traumatic servity and blood cAMP and cGMP levels in the patients with acute trauma and its clinical significance, 120 cases of trauma were randomly selected and divided into 4 groups (n=30 in each group): mildly traumatic group (ISS≤9), moderately traumatic group (ISS=10–16), severely traumatic group (ISS=17–25) and dangerously traumatic group (>25). The cAMP and cGMP levels were assayed in sera, leucocytes and platelets respectively in 6 h and 24 h after trauma. The results showed that cAMP and cGMP levels were elevated significantly in sera and platelets (P<0.05 orP<0.01), meanwhile cGMP levels in leucocytes (P<0.05). It was concluded that cAMP and cGMP might play an important role in traumatic stress, participate in the cellular signal transducation and promote the immune function of leucocytes and the coagulation founction of platelets. Serum cAMP and cGMP levels were upregulated correspondingly as ISS increased, and positively correlated to the traumatic severity.

Protective effect of interleukin-1β (IL-1β) on motor neurons was studied after peripheral nerve injury. Twenty Wistar rats were divided into 2 groups randomly. The right sciatic nerve of each rat was resected. After silicon tubulization of sciatic nerve in rat, 15 μl 1 ng/ml IL-1β and PBS solution were injected into the silicon capsule respectively. Enzyme histochemistry was performed to show acctyle cholesterase (AchE) and nitric oxide staining (NOS) activity of spinal α motor neurons in spinal segments 2 weeks later. Neurons were counted and the diameter and cross sectional (c/s) area of neurons were analyzed by using computer image analysis system. The results showed that as compared with the normal side, both enzyme activities significantly changed in motor neurons in PBS group. The diameter and c/s area of both neurons changed significantly too (P<0.01). These results suggest that exogenous IL-1β protects α-motor neurons from degeneration and necrosis after peripheral nerve injury.

The cortexes were obtained from new-born rats and dissociated to single cells by triturating. The cells were cultured in neural stem cell (NSC) culture medium (DMEM supplemented with bFGF, EGF and B27) and formed primary neurospheres after 7 days. Single cells dissociated from neurosphere were cultured in 96-well plates and formed single-cell cloning neurosphere 7 days later. The primary and single-cell cloning neurospheres were both positive for the immunofluorescent staining of nestin and were identified as NSC. It was proved that NSC can be expandedin vitro and provide seed cells for neural tissue engineering.

The involvement of apoptosis in mitochondrial toxin 3-nitropropionic acid (3-NPA)-induced ischemic tolerance to transient focal cerebral ischemia in rats and the mechanism was investigated. 3-NPA at a dose of 20 mg/kg or vehicle control was intraperitoneally into the rats. Three days later, rats were exposed to 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion. Infarct volumes were assessed by 2, 3, 5-triphenyltetrazolinm chloride (TTC) staining 24 h after reperfusion. Neural cell apoptosis in cerebral ischemic penumbra was detected by terminal deoxynucleotidyl trnasferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) and flow cytometry methods (FCM). The results showed that as compared to the vehicle-treated group, pretreatment with 3-NPA could reduce the infarct volume by 23.3% and decrease the number of TUNEL-positive neural cells and apoptotic percentage by 47% (P<0.05) and 44.9% (P<0.01). respectively. It was concluded that the development of 3-NPA-induced ischemic tolerance in brain might be related to the decreases in neural cell apoptosis.

In order to investigate the neurotoxicity of lipopolysaccharide (LPS) on the dopaminergic neurons of substantia nigra and the pathogenesis of Parkinson disease. LPS was stereotaxically infused into substantia nigra (SN). At different dosages and different time points with 5 μg LPS, the damage of the dopaminergic neurons in SN was observed by using tyrosine-hydroxylase (TH) immunohistochemical staining. The results showed that 14 days after injection of 0.1 μg to 10 μg LPS into the rat SN, TH-positive (TH⁺) neurons in the SN were decreased by 5%, 15%, 20%, 45%, 96% and 99% respectively. After injection of 5 μg LPS, as compared with the control groups, TH⁺ neurons began to decrease at 3rd day and obviously decrease at 14^th day, only 5% of total cells, and almost disappeared 30 days later. The results suggested that LPS could induce the degeneration of dopaminergic neurons in the SN in a dose- and time-dependent manner.

Whether transforming growth factor-β₂ (TGF-β₂) induces apoptosis of human trabecular meshwork cells was investigatedin vitro. Cultured 3–5 passage human trabecular meshwork cells were treated with 0 (control). 0. 32. 1, 3. 2 ng/ml TGF-β₂ for 48 h and divided into control group and experimental group. The apoptosis of human trabecular meshwork cells was examined by transmisson electron microscopy. TUNEL technique and flow cytometry. The results showed character istic morphologic changes of apoptotic cells were observed under transmission electron microscopy. DNA fragmentation of human trabecular meshowork cells was found by TUNEL technique. Quantitative analysis of flow cytometry showed that percentages of apoptotic human trabecular meshwork cells were (2.79±0.44)%. (4.43±1.17)% and (9.60±2.05)% respectively with different concentrations [1 ng/ml (P<0.05), 3.2 ng/ml (P<0.01)] of TGF-β₂ with the difference being significant between experimental group and control group [(1.41±0.34)%]. It was concluded that TGF-β₂ can induce apoptosis of human trabecular meshwork, cellsin vitro and may be involved in the decrease of trabecular meshwork cells in the patients with primary open angle glaucoma and aging of normal people.

In order to investigate the correlation between the expression of the apoptotic regulatory proteins (Fas, Blc-2) in peripheral blood lymphocytes (PBLC) and the level of IFN-γ and IL-4 in serum of the patients with condyloma acuminata (CA) in the immune pathogenesis of CA, indirect immunofluorescence labeling method of flow cytometer and solid sandwich ELISA method were performed for detecting the expression of Fas, Bcl-2 in PBLC and the level of IFN-γ and IL-4 in serum of 60 cases of CA. The results showed the expression level of Fas in PBLC of CA was significantly higher than in the normal control group, but the expression level of Bcl-2 was significantly lower (bothP<0.01). The level of IFN-γ in serum of CA was significantly lower than in the normal control group (P<0.01), but IL-4 was significantly lower (bothP<0.01). The expression of Fas in PBLC had a negative correlation with the level of IFN-γ in serum of patients with CA, but had a positive correlation with the level of IL-4: The expression of Bcl-2 had a positive correlation with the level of IFN-γ, but had a negative correlation with the level of IL-4. All the correlation coefficients had significant differerce byt test (P<0.01). It was suggested abnormal apoptosis in PBLC, the suppressed secretion of the TH1-associated cytokines (eg: IFN-γ) and the increased secretion of the TH2-associated cytokines (eg: IL-4) existed in the patients with CA and might play an important role in the immune pathogenesis of CA.

By using distraction osteogenesis technique, 3 cases of mandibular hypoplasia were treated by home-made and German-made jaw distractors: including one patient suffered from bilateral ankylosis of temporo-mandibular joint and 2 patients from deficiency of mandible. The duration of distraction osteogenesis was one month. The bone distractor was removed 3 months after operation. Satisfactory results were obtained in all 3 cases. Distraction osteogenesis can successfully be used in mandibular functional reconstruction and has much more advantages than traditional technique.

The value of combined application of both ECG-gated cine MRA and 3D-CEMRA in the detection of large intracranial aneurysms was evaluated and the findings were compared with those of conventional MRA and DSA. Twenty-four patients with 26 large intracranial aneurysms underwent MRI and DSA. All these aneurysms, diameter from 15 to 39 mm, were located at internal cerebral artery (n=12), vertebral artery (n=3), basilar artery (n=4), anterior cerebral artery (n=2), middle cerebral artery (n=2), anterior communicate artery (n=2) and posterior communicate artery (n=1). Thirteen cases of hematoma or cavernoma were studied as control group. All patients were examined on GE 1. 5T MR system. ECG-gated cine MRA was performed with 2D multi-phase fast gradient-recalled echo sequence in a single section. All the images were analyzed with signal intensity VS time curve for differentiating intraaneurysmal blood flow from static tissue. The results were analzsed by statistic “t” test. 3D-CEMRA was performed with spoiled gradient-recalled echo and one dose of Gd-DTPA. All data was processed with multi-plannar reformat (MPR) and tomography for the demonstration of aneurysms in detail. All 26 aneurysms were demonstrated successfully by combined application of both cine MRA and 3D-CEMRA. Compared to DSA and conventional 3D-MOTSA, its sensitivity and specificity figures were both 100%. Cine MRA could differentiate the blood flow from the static tissue. The intensity VS time curves of intraaneurysmal blood flow offered fluctuating form and average signal change between systole and diastole period was about 89.8±37.4; However, under the control group, intraaneurysmal thrombus or cerebral hemorrhage or cavernomas had no significant signal change and the curves offered steady form with the average signal change being about 8.2±6.3. There was statistically significant difference between the intraaneurysmal blood flow and static tissue (P=0.025, <0.05). 3D-CEMRA was very useful in demonstrating the aneurysmal size, intraaneurysmal thrombus formation, neck and the detailed relationship of the aneurysm to the surrounding structures. It was concluded that the combined application of both cine MRA and 3D-CEMRA might be a valuable clinical tool for the detection of large intracranial aneurysms.

The MRI appearances of 7 adult patients with pathologically proven intracranial primitive neuroectodermal tumors (PNET) were retrospectively analyzed. The MRI features were compared with findings in pathology and surgery. In this group, the tumor masses were most commonly found in the semisphere of cerebrum and in the vermis of cerebellum. They were relatively large and 4 were in lobulated shape. All of them had well-defined margins. MR images showed the tumors to be mildly or obviously hypointense on T₁-weighted images and hyperintense on T₂-weighted images. Most masses had heterogeneous appearances with some cystic and necrotic areas. Intratumoral haemorrhage and focal calcification were occasionally seen. Mostly, there was no or only mild surrounding edema. Marked inhomogeneous contrast enhancement on MRI was seen in 6 cases except one. Two patients with multiple intracranial metastases were revealed on MR images. In this series, there was good correlation between MRI features and findings in pathology and surgery. These results showed that certain MRI features might suggest the diagnosis of intracranial PNET in adults. MRI is an effective technique to detect these tumors and is helpful to treatment planning and follow-up.

In China, the implementation of community health service shows that the prevention is an essential and important part of our national health system and is helpful to decrease the medical expenditure gradually. According to the data from Health Statistic Information Center of Ministry of Health in China, we calculated that the total health expenditure of China would be decreased 8000.0 million yuan only in 2001, among which, 1188.3 million, 1953.9 million and 4833.0 million yuan were respectively saved for the government budget, the society and resident if implementing the policy of community health service powerfully. And every outpatient can save 15. 46 yuan per time. By the quantitative analysis on the economic contribution of community health service, it can be proved that a great economic benefit could be gotten from the implementation of community health service.