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Since Src kinase inhibitors decrease brain injury produced by intracerebral hemorrhage (ICH) and thrombin is activated following ICH, this study determined whether Src kinase inhibitors decrease thrombin-induced brain injury. Thrombin injections into adult rat striatum produced focal infarction and motor deficits. The Src kinase inhibitor PP2 decreased thrombin-induced Src activation, infarction in striatum and motor deficits in vivo. Thrombin applied to cultured post-mitotic striatal neurons caused: injury to axons and dendrites; many TUNEL positive neuronal nuclei; and re-entry into the cell cycle as manifested by cyclin D1 expression, induction of several other cell cycle genes and cyclin-dependent kinase 4 activation. PP2 dose-dependently attenuated thrombin-induced injury to the cultured neurons; and attenuated thrombin-induced neuronal cell cycle re-entry. These results are consistent with the hypotheses that Src kinase inhibitors decrease injury produced by ICH by decreasing thrombin activation of Src kinases and, at least in part, by decreasing Src induced cell cycle re-entry.

Pinewood nematode (Bursaphelenchus xylophilus) is an invasive species that causes a destructive forest disease-pine wilt disease. This disease has been prevalent in some countries in Asia since the 1970s. An amplified fragment length polymorphism survey was used to compare the genetic variation of native and invasive nematode populations in China and to examine the changes in genetic diversity during the invasion process. The genetic diversity of Chinese populations was slightly higher than that of American populations. Analysis of groups sampled from different invasive stages in China, showed that no obvious change in genetic diversity. Hence, genetic drift and founder effects are not obvious in the invasion process. Phylogenetic analysis showed that Chinese pinewood nematode populations were closer to Japanese populations than to American populations. On the basis of the genetic relationships among samples, two major invasion pathways in China are suggested. One is from Guangdong to Anhui and Zhejiang, and the other is from Guangdong to Jiangsu and then from Jiangsu to Hubei, Guizhong and Congqing. The results imply that it is important to reinforce both domestic and international quarantine to control the spread of pinewood nematode.

Objective: To evaluate the clinical value of activated carbon nanoparticles for guiding lymphadenectomy in lung cancer., Methods: Fourty-two lung cancer patients were divided into two groups: the control group (22 cases) and experiment group (20 cases) who received activated carbon nanoparticles injection around the tumor either by endoscopic injection or intraoperative subserosal injection. The number of dissected lymph node, black-stained lymph node, positive lymph node and the side effect of the procedure were analyzed, respectively., Results: No severe complication was observed in the experiment group. The operative time was not prolonged significantly in the experiment group either. However, the number of average lymph nodes dissected in the experiment group (25.5) was significantly more than that in the control group (14.6) (P <0.01)., Conclusion: Local injection of activated carbon nanoparticles around the tumor during surgical exploration is effective, safe and easy to do for guiding lymphadenectomy in lung cancer patient.

The effect of osmotic stress on cell growth and phenylethanoid glycosides (PeGs) biosynthesis was investigated in cell suspension cultures of Cistanche deserticola Y. C. Ma, a desert medicinal plant grown in west region of China. Various initial sucrose concentrations significantly affected cell growth and PeGs biosynthesis in the suspension cultures, and the highest dry weight and PeGs accumulation reached 15.9 g l(-1)-DW and 20.7 mg g(-1)-DW respectively at the initial osmotic stress of 300 mOsm kg(-1) where the sucrose concentration was 175.3 mM. Stoichiometric analysis with different combinations of sucrose and non-metabolic sugar (mannitol) or non-sugar osmotic agents (PEG and NaCl) revealed that osmotic stress itself was an important factor for enhancing PeGs biosynthesis in cell suspension cultures of C. deserticola. The maximum PeGs contents of 26.9 and 23.8 mg g(-1)-DW were obtained after 21 days at the combinations of 87.6 mM sucrose with 164.7 mM mannitol (303 mOsm kg(-1)) or 20 mM PEG respectively, which was higher than that of C. deserticola cell cultures grown under an initial sucrose concentration of 175.3 mM after 30 days. The stimulated PeGs accumulation in the cell suspension cultures was correlated to the increase of phenylalanine ammonium lyase (PAL) activity induced by osmotic stress.

Objectives: To establish a reversed phase high performance liquid chromatographic method with pre-column ultraviolet derivatization for the determination of perfluorooctanoic acids (PFOA) in sewage and urine., Methods: PFOA in sewage and urine formed an ion-pair with tetrabutylammonium (TBA) and were extracted into MTBE. The PFOA then reacted with omega-bromoacetophenone (omega-BAP) in acetonitrile and produced materials quantifiable by HPLC with UV detector., Results: The detection limit of the proposed method was 7.0 microg/L with a relative standard deviation of less than 10%. The recoveries for real samples ranged from 85.3% to 116%., Conclusion: The proposed method is suitable for the determination of PFOA in sewage and urine.

Objective: To evaluate the effect of JAK/STAT signaling pathway activation on the transdifferentiation and secretion of transforming growth factor-beta1 (TGF-beta1) induced by high glucose in renal proximal tubular epithelial cells., Methods: Human kidney cells (HKC) were cultured and then divided into four groups: low glucose (LG) group, high glucose (HG) group, high mannitol (LG + M) group, and HG + AG490 group. Immunoprecipitation and Western blot analysis were used to determine the expression of tryosine phosphorylated Janus kinase 2 ( p-JAK2). The protein expressions of STAT1, STAT3, p-STAT1, and p-STAT3 and the expressions of alpha-SMA and E-Cadherin were observed by Western blot. The contents of TGF-B1, fibronectin and type I collagen in the supernatants of the cultured HKC were detected by enzyme-linked immunosorbent assay (ELISA). The expression of TGF-beta1 mRNA was measured by reverse transcription and polymerase chain reaction (RT-PCR)., Results: Compared with LG group, the expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta1, mRNA were significantly increased in HG group from 6 to 72 hours. Meanwhile, the contents of TGF-beta1 and collagen I in the supernatants and the expression of alpha-SMA increased and the expression of E-Cadherin decreased. The expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta mRNA as well as the levels of TGF-beta1 and collagen I in the supernatant s in HG + AG490 group were significantly lower than in the HG group. The expressions of alpha-SMA and E-Cadherin were also decreased in HG + AG490 group., Conclusion: Activation of JAK/STAT signaling pathway may be involved in the high glucose-induced transdifferentiation and overproduction of TGF-beta1, and ECM proteins in HKCs.

Objective: To investigate the treatment for postoperative recurrence of spontaneous pneumothorax, the feasibility of re-operation, indications and the results., Method: The clinical and follow-up data of 28 cases of postoperative recurrence from 485 patients who underwent operations for spontaneous pneumothorax from Jan, 1994 to Jan, 2005 were retrospectively reviewed., Results: One case was observed without any invasive therapy, 12 cases underwent closed pleural drainage and 15 cases received reoperation. All of the patients had the lungs reexpanded sufficiently, with comorbidities in 2 cases, one of which was pleural effusion, the other was prolonged leakage after surgery. No death occurred. The operation time was 80 - 315 (115 +/- 43) min, and the bleeding volume was 50 - 350 (115 +/- 54) ml. The time of chest tube drainage was 1 - 7 (4 +/- 2) d, and the time of hospital stay was 7 - 18 (11 +/- 5) d. The follow-up of the 28 cases ranged from 1 to 107 months (median 55.4) without recurrence., Conclusions: The findings on lung high rate CT (HRCT) are the most important factors in deciding treatments of postoperative recurrence of pneumothorax. If it is the first recurrence, and there is no evident bullae on HRCT, conservative therapy should be considered, especially for the recurrence within two years postoperation. If the first recurrence occurs after surgery, especially within 2 years, and the bullae is invisible on HRCT, adhesion is the choice without significant adverse effect. If the recurrence occurred twice and more, bullae is found on HRCT, adhesion hampered lung reexpansion, or pleural drainage alone could not work, re-operation should be performed.

'Bright Yellow 2' ('BY-2') tobacco (Nicotiana tabacum L.) suspension cells could not proliferate even with proper 2, 4-D concentration (0.6 mg/L) in the medium, when the initial cell density is low. However, the cells could divide and grow normally if conditioned medium (CM) was added to the medium, and the rate of proliferation of cells was proportional to the quantities of CM supplied. The same results were obtained, when the CM was replaced by synthesized phytosulfokine-alpha (PSK-alpha), a sulfated pentapeptide, PSK-alpha was found in CM of 'BY-2' cells by MS identification. From the significant linear relationship between rate of cell proliferation (measured by OD600 value) and concentrations (0.05 nmol/L-10 micromol/L) of PSK-alpha, it can be seen that the 'BY-2' suspended cells are the ideal plant material for bioassay of PSK-alpha. This result suggests that the PSK-alpha might be involved in promoting the proliferation of 'BY-2' suspension cells.

The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum (La) on nitrogen metabolism under two different levels of elevated UV-B radiation (UV-B, 280-320 nm). The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m2 and high level 0.45 W/m2 significantly affected the whole nitrogen metabolism in soybean seedlings (p < 0.05). It restricted uptake and transport of NO3(-), inhibited activity of some key nitrogen-metabolism-related enzymes, such as: nitrate reductase (NR) to the nitrate reduction, glutamine systhetase (GS) and glutamine synthase (GOGAT) to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase (GDH), which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La (20 mg/L), La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.

Objective: The study was to investigate the effect of different temperatures during hypoxia on brain injury in mice of different ages., Methods: Newborn C57/BL6 mice at 7 days or 21 days of life were subjected to left carotid artery ligation followed by exposure with 10% oxygen. The mice were kept in a incubator with a predetermined, constant temperature, either 34 degrees centigrade (Hypothermia group) or 36 degrees centigrade (Normothermia group). Brain injury was evaluated 7 days after hypoxia-ischemia (HI). Active caspase-3 and apoptosis-inducing factor (AIF) expressions in the brain tissue were detected by immunohistochemistry and Western Blot was used to evaluate the phosphor-Akt (P-Akt) expression in the brain tissue at 24 hrs post-HI., Results: Brain injuries, including the cortex, hippocampus, striatum and thalamus injuries, occurred in the Normothermia group at 7 days post-HI. The brain cortex showed cystic cavitation in the postnatal day (P)7 pups mice and laminar infarct of the brain cortex was observed in P21 mice. In the Hypothermia group, the P7 mice did not present with laminar infarct of the cortex and had lower scores of neuropathological lesions in cortex, hippocampus, striatum and thalamus than P7 mice from the Normothermia group (P < 0.01); the cortex injuries were significantly relieved but the injuries of hippocampus, striatum and thalamus in P21 mice were similar to those from the Normothermia group. Active caspase-3 (7.0 +/- 5.6) and AIF positive cells (3.7 +/- 6.2) in the cortex of P7 mice from the Hypothermia group were significantly lower than those of the Normothermia group (51.5 +/- 23.2 and 31.8 +/- 22.4) at 24 hrs post-HI (P < 0.01). Wetstern Blot showed the P-Akt expression was obviously decreased in the ipsilateral hemisphere to the occlusion compared with that of the contralateral hemisphere after HI in the Normothermia group (P < 0.05), while in the Hypothermia group the P-Akt expression was not significantly different between the two hemispheres., Conclusions: Hypothermia has protective effects against HI insults. The protection was more pronounced for the immature brain than the mature brain.

Objective: To report the management of the contralateral lungs in 4 cases with single allograft lung transplantation., Methods: Four cases receiving lung transplantation were analyzed respectively. One presented with bilateral multiple lung cysts and three with chronic obstructive pulmonary disease (COPD) with bilateral bullae. In the case with bilateral multiple cysts, the contralateral lung remained untreated after operation. For the contralateral lungs in the three cases with COPD, one remained untreated, one received lung volume reduction surgery (LVRS) immediately after lung transplantation, and one received LVRS 47 days after lung transplantation., Results: Three patients recovered after operation, and 2 of them survived more than 18 months. One patient with delayed contralateral LVRS died 74 days after lung transplantation., Conclusions: For advanced stage COPD with bilateral bullae, contralateral LVRS may be performed immediately after single lung transplantation. In patient with bilateral cysts only, the resection of the contralateral cysts may be avoided if there is no severe infection.

Objective: p53-induced apoptosis is crucial in the development of hypoxic-ischemia (HI) brain damage and neurodegenerative disorders. Some experimental research has shown that a synthetic inhibitor of p53 can protect neurons against apoptosis. This study aimed to explore the expression of p53 in neonatal mice following HI brain damage and the effect of p53 inhibitor (pifithrin-alpha, PFT-alpha) on brain damage., Methods: HI was induced in 9-day-old mice pups by ligation of left carotid artery and 10% oxygen exposure for 55 minutes. The pups were sacrificed and the brains were taken out at 3, 8, 24, and 72 hrs post-HI. The brains were sectioned and stained with antibody against p53 and microtubule-associated protein 2 (MAP-2). PFT-alpha was injected intraperitoneally: in experiment 1, immediately after HI with different dosages (1, 2 and 8 mg/kg); in experiment 2, 2 mg/kg at different HI times (1 hr before HI, and immediately and 1 hr after HI). Control animals without HI received injections of 0.5% dimethyl sulfoxide. Brain damage was evaluated by gross morphology scoring at 72 hrs after HI., Results: The number of p53 positive cells in the cortex, hippocampus and striatum of the ipsilateral hemisphere increased significantly and peaked at 3-8 hrs post-HI when compared with those of contralateral hemisphere as well as normal controls. The positive cells distributed mainly in the MAP-2 negative area. Both different dosages and different injection time PFT-alpha treatment did not reduce the extent of brain damage., Conclusions: The immunoactivity of p53 increased significantly as early as 3 hrs post-HI. The distribution area of p53 expression was consistent with that of brain damage. The p53 inhibitor PFT-alpha has no protective effects against HI brain damage in neonatal mice.

Effect of chitosan elicitor on growth and phenylethanoid glycosides (PeGs) accumulation in Cistanche deserticola cell suspension cultures was investigated. PeGs accumulation was dramatically improved by addition of selected chitosan at optimal elicitation conditions. Furthermore, a strategy of repeated addition of the chitosan elicitor for enhancing PeGs accumulation was developed. The chitosan elicitor of 10 mg l(-1)-medium repeatedly added on days 15 and 17 improved PeGs accumulation further, and the final PeGs production in the treated cell cultures of C. deserticola reached 364.6 mg l(-1), which was 3.4-fold higher than that of the control without elicitation. The increase of PeGs accumulation in C. deserticola cell suspension cultures was related to the increase of phenylalanine ammonium lyase activity stimulated by the chitosan elicitor.

Objective: To explore the therapeutic effect of interleukin-11 (IL-11) on high-dose methotrexate (HDMTX) induced mucositis in Wistar's rats, the proliferative effect on CEM leukemia cell line and the antitumor effect on HDMTX., Methods: Ninety-five 5-week old, 120 - 150 grams weight Wistar rats were randomly divided into five groups. Group A is normal control (n = 15), group B MTX control (n = 20), group C IL-11 pretreatment group before MTX injection (n = 20), group D (n = 20) the high dose IL-11 group (475 microg.kg(-1).d(-1)) after MTX injection, group E (n = 20) the low dose IL-11 group (150 microg.kg(-1).d(-1)) after MTX injection. All rats in group B approximately E were given 1 ml MTX intraperitoneally (100 mg/kg). Rats were killed at day 1, 3, 5, 7 after MTX injection. The mortality rates, changes of small intestine tissue morphology and ultra structure were observed. The proliferation of small intestine crypt cell was assayed by proliferating cell nuclear antigen (PCNA) immunohistochemical staining. MTT method was used to detect the proliferation of CEM cell line., Result: IL-11 treatment resulted in a significant increase of survival of HDMTX treated rats, increased of small intestinal villus length and villus/crypt ratio. IL-11 administration was associated with enhancement of small intestine mucosa recovery after HDMTX therapy. Group C showed a greater effect than group B (P < 0.01). IL-11 had no effect on CEM cell proliferation., Conclusion: IL-11 has a significant mitigating effect on high-dose MTX induced intestinal mucositis in rat, and significantly increase the survival of the rats. IL-11 could be safely used in the HDMTX treatment of childhood acute lymphocyte leukemia.

Objective: To study the relation of cytochrome C release from mitochondria to cytosol and neuronal apoptosis after cerebral hypoxia-ischemia (HI) in neonatal rats., Methods: Hypoxia-ischemia was induced in 7-day-old rat pups by ligation of left carotid artery and 7.7% oxygen was inhaled for 55 min. The pups were sacrificed and the brains were taken out at different recovery time. Some of the brains were homogenized and cellular fraction of mitochondria and cytosol was isolated with different speed centrifugation. The cellular fraction was used for Western blotting. Some of the brains were sectioned and stained with antibody against cytochrome C and TUNEL as well as double labeling with different combinations., Results: Western blots showed that cytochrome C in mitochondria was not reduced significantly at 1 h, but reduced markedly at 14 h in ipsilateral hemisphere post-HI. However, the immunoreactivity of cytochrome C in cytosol was increased markedly at 1 h post-HI and reached peak at 14 h post-HI. The number of cytochrome C positive cells in the cortex was increased significantly at 1 h (8.4 +/- 1.8/visual field) compared to normal control (1.5 +/- 0.8/visual field) (P < 0.01) and reached peak at 14 h (29.0 +/- 5.2/visual field) post-HI. The number of TUNEL positive cells increased significantly at 1 h post-HI (14 +/- 3/visual field) compared to normal control (1.5 +/- 0.8/visual field) (P < 0.01) and reached peak at 24 h (286 +/- 86/visual field). The double labeling of cytochrome C and active caspase-3 showed that they colocalized well at 3 h after HI. Furthermore, the positive cells showed nuclei condensation. There were more active caspase-3 positive cells at late recovery (24 h and on) after HI. The double labeling of cytochrome C and TUNEL showed only part of Positive cells colocalized. The cells with cytochrome C strong staining showed TUNEL negative or weakly positive. The cells with TUNEL strong staining showed weakly cytochrome C staining., Conclusion: Cytochrome C release is one of the early biochemical changes of neuronal apoptosis after hypoxia-ischemia in neonatal rat brain.

Background: Human cytochrome P450 2A13 (CYP2A13) is involved in the activation of numerous toxicants and carcinogens, especially in the metabolic activation of 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a major tobacco-specific carcinogen. A functionally significant coding single nucleotide polymorphism (C3375T) in exon 5 of CYP2A13, which results in an amino acid substitution of Arg 257 to Cys, has been recently reported to exist in White, Black, Hispanic, and Asian individuals, with the variant 3375T allele frequencies being 1.9%, 14.4%, 5.8% and 7.7%, respectively. Since genetic background differs between ethnic groups, our present study aims to characterize the CYP2A13 Arg257Cys polymorphism in Chinese., Methods: 258 healthy Chinese Han volunteers were involved in this study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was employed to genotype for the Arg257Cys polymorphism., Results: Of all the 258 subjects, 27 (10.5%) heterozygotes and 1 (0.4%) homozygote for the 257Cys allele were detected. The frequency of the variant 257Cys allele in this Chinese population was 5.6% (95%CI: 4.2-7.0%)., Conclusion: The CYP2A13 Arg257Cys variant represents a common polymorphism in Chinese, with the 257Cys allele frequency being similar to the Hispanic and Asian groups, but significantly lower than the Black.

Unlabelled: Enzyme ablation of the hyperplastic prostate may be an ideal method of management of BPH. However, the unsatisfactory ablation affects in vivo contrast with successful in vitro results limiting the enthusiasm for further research. In this study, we make efforts to solve the problems in the use of enzyme ablation of BPH in vivo and to measure satisfactory effect., Material and Methods: A total of 18 hybrid dogs between the ages of 7 and 11 y underwent this experiment. Eight dogs were divided into four groups according to the injection formula: enzyme solution, hot D-Hanks' plus enzyme solution, hot agarose plus enzyme solution, and hot agarose solution alone. After selecting the agarose plus enzyme solution group in the first month, the remainder 10 dogs were treated with this two-stage method. Intravenous or oral antibiotics were administered perioperatively. All operations were performed directly by way of laparotomy. The prostates were observed and harvested with surrounding tissue at 24 hrs, 7 days, 14 days, 1 month and 3-5 months after treatment. Gross and microscopic examinations were performed., Results: Only agarose plus enzyme group shows obvious cavity formation with concomitant size reduction and softening of the prostate ablation effect in the four groups. At 24 h after injection, the prostates demonstrated cavity formation containing liquefied necrotic tissue. The liquefied tissue was absorbed in 7-14 days. At 1 month, the size of most prostates decreased with a corresponding decrease in the size of the cavities. The cavities nearly disappeared within 3-5 months, and the size of prostates decreased to between 1/2 and 1/4 of the pretreatment sizes. All prostates had intact urethral mucosa and capsule. No complications directly related to enzyme ablation were identified. In the control groups there were no significant cavities or decrease in prostate size., Conclusions: This two-stage thermal and enzyme ablative method can significantly ablate prostate tissue without identifiable complications, and would be possibly applied to treating human BPH in the future.

Objective: Recent studies suggest that hypothermia may be a potential treatment for perinatal hypoxic-ischemic (HI) brain damage. But the mechanisms of this effect are not well known. In the present study, the protective effect of systemic hypothermia as well as effect on apoptosis and associated biochemical events were investigated on neonatal rats with HI brain damage., Methods: Seven-day-old Wistar rats were subjected to left carotid artery ligation and hypoxia was persisted for 60 min. Immediately at the end of hypoxia, the animals were maintained either at 36 degrees C or 30 degrees C for 10 h at random. Caspase-2, 3 activity in brain homogenate was detected with Western blotting at 24 h post-HI (n = 8 for each group). Immunoactivity of microtubule-associated protein-2 (MAP-2), active caspase-3, apoptosis inducing factor (AIF) and oligonucleotide hairpin probe staining were detected at 72 h post-HI. The infarct volume, neuronal loss in CA(1) sector of hippocampus as well as brain injury scoring were calculated according to MAP-2 staining and hematoxylin and eosin staining., Results: Caspase-2, 3 activities were much higher in the normothermia group [(27.7 +/- 14.7), (94.9 +/- 53.1) pmol/(min.mg protein)] at 24 h post-HI than those of hypothermia [(7.9 +/- 3.4), (21.1 +/- 18.7) pmol/(min.mg protein)] and normal control groups [(7.6 +/- 0.7), (12.9 +/- 0.5) pmol/(min x mg protein)] (P < 0.01). The activities were not significantly different between hypothermia group and normal control group. Western blotting showed that caspase-3 activation process was blocked by hypothermia. The number of active caspase-3 and AIF positive cells in the cortex of ipsilateral hemisphere was much higher in the normothermia group (median: 148.5; 22/field) than that of hypothermia group (median: 48.5; 9/field) (P < 0.05). The number of apoptotic cells as judged by oligonucleotide hairpin probe labeling was much higher in normothermia group (median: 144/field) than that of hypothermia group (median: 133/field) (P < 0.05). The brain injury scoring, infarct volume and neuronal loss in CA(1) area of hippocampus were much less in the hypothermia group [10.4 +/- 2.9; 40.5 +/- 34.8)mm(3); 25.7 +/- 11.5] than that of normothermia group [14.2 +/- 3.5; (73.9 +/- 22.4) mm(3); 37.4 +/- 10.6, P < 0.05]., Conclusions: Systemic hypothermia for 10 h after hypoxia-ischemia seemed to be effective in reducing brain damage and the mechanism is associated with alteration of apoptotic pathway.

Aim: To study the effects of transcriptional factor Sp1 antisense oligodeoxynucleotide (ODN) on telomerase activity and human telomerase reverse transcriptase (hTERT) expression., Methods: Antisense oligodeoxynucleotide (ODN) was designed to inhibit Sp1 expression and transferred to Jurkat T cells by lipofectamin. Telomerase PCR-ELISA was used to detect telomerase activity. RT-PCR analysis was used to assess the mRNA expression of Sp1 and hTERT, and Western blot was used to analyze the levels of Sp1 protein., Results: Treatment of Jurkat T cells with Sp1 antisense ODN (1 micromol/L) dramatically reduced Sp1 mRNA and protein levels. The inhibition rate was 44.8 % (P <0.05) and 57 % (P <0.01), respectively. Following the transcriptional factor Sp1 functionally altering, hTERT mRNA expression were suppressed with a 43.7 % inhibition rate (P <0.01). A dose-dependent inhibition of telomerase activity by antisense Sp1 ODN was also discovered. From 0.25 to 2.0 micromol/L, telomerase activity was reduced from 27.1 % to 64.6 %., Conclusion: Antisense Sp1 ODN decreases telomerase activity by inhibiting hTERT mRNA expression in Jurkat T cells.

Our project is designed to clone a 1.3kb gene fragment of telomerase catalytic subunit gene which contains seven reverse transcriptase motifs and specific region with conserved sequence termed "T motif". The gene fragment was amplified by PCR and was inserted into expression vector pET28-b. The recombinant plasmid was induced by IPTG for 4h and a 52KD recombinant protein was produced. Amount of hTRT recombinant protein expression was 20% of total bacterial protein in the form of inclusion. Inclusion was dissolved in 8 mol/L urea and 10 mmol/L DTT and carried out affinity purification under denaturing condition. The purified hTRT recombinant protein was conformed by Western-blot successfully.

The effect of zinc ions on caffeine-induced contracture in vascular smooth muscle and skeletal muscle of rat was studied. In aortic strips, caffeine contracture was depressed by Zn2+ in a dose-dependent manner. Moreover, the extent of the depression of caffeine contracture in the Zn2+ loaded smooth muscle increased with repetitive caffeine exposures. For instance, in the preparations perfused with a medium containing 100 microM [Zn2+] for 15 or 30 min, the first caffeine contractures were similarly depressed to about 60% of the control. However, the subsequent caffeine exposure at 15 min interval could not evoke any contracture. In this study this feature is referred to as activation dependence of the Zn2+ effect. In small bundles of soleus muscle 2ñ100 microM [Zn2+] similarly caused a depression of caffeine contracture, and the activation dependence also was evident. However, an evident potentiation of caffeine contracture was seen in the preparations loaded with lower [Zn2+] such as 0.5 microM, indicating that the effect of Zn2+ on caffeine contracture of skeletal muscle was somewhat different from that seen in smooth muscle. By observing how the depression effect depends on the intervals between caffeine exposures as well as on caffeine concentrations, it is indicated that the activation dependence of the Zn2+ effect, at least in skeletal muscle, may not be explained by depletion of intracellular Ca2+ stores alone. The possible mechanism for that caffeine contracture of smooth muscle and skeletal muscle was differentially affected by Zn2+ ions is discussed., (Copyright 2002 S. Karger AG, Basel)

Two transgenic rice (Oryza sativa L.) lines, KMD1 and KMD2 at the R4 generation, transformed with a synthetic cry1Ab gene from Bacillus thuringiensis Berliner, were first evaluated for stem borer resistance in the field during the rice growing season of 1998 in two areas of Zhejiang Province, China. Both KMD1 and KMD2 were highly resistant to the stem borers Chilo suppressalis (Walker) and Scirpophaga incertulas (Walker), and were completely undamaged during the whole rice growing season. In contrast, damage to the plants of the untransformed parental control (Xiushui 11) was in the form of deadhearts or whiteheads. Under natural infestation by the C. suppressalis, the damage to control plants reached a peak of 88.7% of plants and 20.1% of tillers encountered with deadhearts. Under artificial and natural infestation of neonate striped stem borers at the vegetative stage and booting stage, 100% of plants and 25.6% of tillers, 78.9% of plants and 15.6% of productive tillers among artificially infested control plants were observed with the symptom of deadhearts and whiteheads, respectively. Damage to the control plants from artificial infestation by the S. incertulas reached a peak of 97.0% of plants and 22.9% of tillers damaged. The field research indicated that both KMD1 and KMD2 show great potential for protecting rice from attack by these two stem borers.

Using the assay of [(3)H]ryanodine binding to the sarcoplasmic reticulum, the effect of Zn(2+) on ryanodine receptors (RyRs) of cardiac muscle was investigated. There was no obvious change in the binding at [Zn(2+)](f) of less than 0.2 microM. However, a decrease of the binding became significant with raising [Zn(2+)](f) to 0.5 microM. The inhibitory effect of Zn(2+) was [Zn(2+)](f)-dependent, with IC(50/ZnI) of 2.1+/-0.4 microM (mean+/-S.D.). Scatchard analysis indicates that both an increase of K(d) and a decrease of B(max) were responsible for Zn(2+)-induced decrease of the binding. The Hill coefficient for this inhibitory effect of Zn(2+) was between 0.8 and 1.2. The interactions of the effects of Zn(2+) and various modulators of RyR indicate that the inhibitory effect of Zn(2+) was mostly mediated through inhibiting Ca(2+) activation sites (CaA) on RyR. Since the [Zn(2+)](f) dependence was not clearly changed by [Ca(2+)](f), the inhibitory effect of Zn(2+) may not be due to competition of Zn(2+) with Ca(2+) for CaA and probably is indirect. The inhibitory effect of Zn(2+) could not be antagonized by 2 mM dithiothreitol, a thiol-reducing agent, suggesting that the binding of Zn(2+) ions to RyRs of cardiac muscle is not accompanied by obvious change of redox state of the RyRs. In comparison with that seen in skeletal muscle [3], the effects of Zn(2+) on ryanodine binding to the sarcoplasmic reticulum of cardiac muscle show several distinct differences. It is indicated that the effect of Zn(2+) on RyRs may be isoform-dependent. The physiological significance of the effects of Zn(2+) is discussed.

A new color reaction of copper (II) with solochrome cyanine R was studied by spectrophotometry. The results were that in the pH6 of HAc-NaAc buffer solution solochrome cyanine R reacted with copper (II) to form a violet complex; the maximum absorption of the complex was at 565 nm and its apparent molar absorption coefficient was 8.25 x 10(5) L.mol-1.cm-1. Beer's Law was obeyed in the range of 0-0.48 microgram.ml-1. This method was used to determine copper levels in the hair samples of 5 normal persons and 5 rheumatoid arthritis patients. The results showed that the hair copper level of arthritis patients was significantly higher than that of normal persons (P < 0.01).

Objective: To observe the features of the cardiovascular reactions to gravitational forces along different axes of the body., Method: Dogs were exposed to gravitational forces along axes of body on an animal centrifuge., Result: It was found that when the direction of G force changed from +Gz to +Gx, the predominating effect on the cardiovascular system changed from the drop of eye level blood pressure to the increase of central venous pressure, and the reactions of the organism changed from a presson reflex of the arterial system to the inhibition of cardiac activities at higher G levels. The turning point was found to be at the back angle of 75 degrees with respect to the direction of the gravitational force., Conclusion: These findings provide an important reference for choosing the optimal seat back angle in a manned space vehicle.

With the use of a [(3)H]ryanodine binding assay, the modulation of skeletal muscle ryanodine receptor (RyR1) by Zn(2+) was investigated. In the presence of 100 microM free Ca(2+) concentration ([Ca(2+)](f)) as activator, the equilibrium [(3)H]ryanodine binding to heavy sarcoplasmic reticulum vesicles was biphasically modulated by Zn(2+). The binding was increased by a free Zn(2+) concentration ([Zn(2+)](f)) of less than 1 microM; a peak binding, approx. 140% of the control (without added Zn(2+)) was obtained at 0.3 microM [Zn(2+)](f). An inhibitory effect of Zn(2+) became obvious with a [Zn(2+)](f) of more than 1 microM; the [Zn(2+)](f) for producing half inhibition was 2.7+/-0.5 microM (mean+/-S.D.). Scatchard analysis indicated that the increase in the binding induced by low [Zn(2+)](f) was due to a decrease in K(d), whereas both an increase in K(d) and a possible decrease in B(max) were responsible for the decrease in binding induced by high [Zn(2+)](f). The binding in the presence of micromolar [Zn(2+)](f) showed a biphasic time course. In the presence of 3 microM [Zn(2+)](f), after reaching a peak with an increased rate of initial binding, the binding gradually declined. The decline phase could be prevented by decreasing [Zn(2+)](f) to 0.5 microM or by adding 2 mM dithiothreitol, a thiol-reducing agent. The [Ca(2+)](f) dependence of binding was changed significantly by Zn(2+), whereas Ca(2+) had no clear effect on the [Zn(2+)](f) dependence of binding. Moreover, some interactions were found in the effects between Zn(2+) and other RyR1 modulators. It is indicated that Zn(2+) can modulate the activation sites and inactivation sites for Ca(2+) on RyR1. The physiological significance of the effects of Zn(2+) on ryanodine binding is discussed.

Thirteen cases of laryngo-pharyngo-cervical oesophagus carcinoma were treated by pharyngo-gastric anastomosis and total laryngectomy. All patients after operation could swallow. The five-year survival rate was 1/4, three-year survival rate was 3/7 and one-year survival rate 9/13. We suggest that resection of pharyngo-laryngo-esophageal, carcinoma with removal of all the pathological lesions and pharyngo-gastric anastomosis is the best way for the prophylaxis of recurrence when the carcinoma involves the cervical esophagus. Furthermore, due to the high tendency of metastasis to neck lymph nodes in the early stage of the carcinoma, neck dissection should be performed during operation. The advantages of pharyngo-gastric anastomosis are wide indication and good blood supply.

The characteristics of the soft-tissue wounds of the hind legs of 155 dogs produced by stainless steel spheres with four different masses and at various impact velocities were observed. It was found that when the mass of the spheres was identical, the velocity became the main factor to determine the severity of the damage; when the mass of the spheres was different but their kinetic energy was similar, then a smaller but faster sphere produced more severe damage than a larger but slower one. Shallow but wide and severe wounds usually resulted. The rate of disability of extremities with such wounds was very high. These wounding properties of steel spheres have caused some new problems in the treatment of war injuries.