Biomedical subjects

X Deng

Publications and source records attributed to X Deng.

At least 55 records · Page 3Linked to original sources

PubMed2001

The minimum alveolar concentration of enflurane for laryngeal mask airway extubation in deeply anesthetized children.

UNLABELLED: The end-tidal anesthetic gas concentration required to prevent the anesthetized patient from coughing or moving during or immediately after the laryngeal mask airway (LMA) extubation is not known. We sought to determine the minimum alveolar concentration of enflurane required for the removal of the LMA in children. We studied 21 nonpremedicated children between 4 and 11 yr of age, ASA physical status I, undergoing procedures below the umbilicus. General anesthesia was induced with a mask by using sevoflurane, nitrous oxide, and oxygen, and the LMA was inserted. Anesthesia was maintained with enflurane, nitrous oxide, and oxygen. At the end of surgery, a predetermined end-tidal enflurane concentration was achieved, and the LMA was removed. Each concentration at which the LMA extubation was attempted was predetermined by the up-and-down method (with 0.1% as a step size). When LMA removal was accomplished without coughing, clenching teeth, or gross purposeful muscular movements during or within 1 min after removal, it was considered a successful LMA removal. Removal was considered to be unsuccessful in patients who developed breath holding or laryngospasm during or immediately after LMA removal. The minimum alveolar concentration of enflurane at which 50% of children had a successful LMA removal was found to be 1.02% (95% CL, 0.95%-1.11%), and the 95% effective dose for successful extubation was 1.14% (95% CL, 1.07%-1.66%). In conclusion, the LMA removal may be accomplished without coughing or moving at 1.02% end-tidal enflurane concentration in 50% of anesthetized children aged 4-11 yr. IMPLICATIONS: There may be fewer problems associated with the laryngeal mask airway extubation when patients are deeply anesthetized. The purpose of this study was to determine the minimum concentration of enflurane for successful removal of the laryngeal mask in children.

Anesthesia, Inhalation↗

PubMed2001

The involvement of multiple protease-antiprotease systems and gut origin sepsis in zymosan-associated endothelial barrier injury and multiple organ dysfunction in rats.

Multiple organ dysfunction syndrome is a dominant cause of mortality in the intensive care unit. Experimentally, a condition similar to the multiple organ dysfunction syndrome can be induced by the intraperitoneal injection of sterile zymosan. In the present study we investigate potential alterations in multiple organ functions, endothelial permeability, and antiproteinases after intraperitoneal injection of zymosan at various doses. Zymosan-induced generalized inflammation lead to endothelial barrier injury in multiple organs/tissues, a decrease in systemic arterial pressure, impaired organ function and gut defence function, and consumption of protease inhibitors, particularly the consumption of alpha2 antiplasmin. Endothelial barrier injury appears to present a dose- and organ-dependent pattern in multiple organs/tissues, and the increase in endothelial barrier permeability occurred prior to organ dysfunction. Zymosan induced the development of multiple organ dysfunction syndrome, probably initiating multiple protease-antiprotease systems, particularly the fibrinolytic system, leading to endothelial barrier injury, tissue edema, parenchymal cell damage, and eventual organ dysfunction, potentially augmented by a secondary bacterial infection.

Animals↗

PubMed2001

Cip4, a new COP1 target, is a nucleus-localized positive regulator of Arabidopsis photomorphogenesis.

Arabidopsis COP1 acts within the nucleus to repress photomorphogenesis, and its nuclear abundance is negatively regulated by light. Here, we report the identification of a COP1-interactive partner, CIP4. CIP4 is a nuclear protein and a potent transcription coactivator. Conditional suppression of CIP4 expression resulted in an elongated hypocotyl and reduced chlorophyll content in the light, indicating that CIP4 is required for the promotion of photomorphogenesis. Furthermore, CIP4 was revealed to act downstream of multiple photoreceptors as well as COP1 in mediating light control of development. CIP4 expression is light inducible and regulated by COP1. However, CIP4 does not play a role in mediating the light induction of anthocyanin accumulation. Together with our previous studies of CIP7 and HY5, our data suggest that COP1 interacts directly with and regulates multiple physiological targets, which in turn regulate distinct sets of light-regulated responses.

Amino Acid Sequence↗

PubMed2001

PYY inhibits CCK-stimulated pancreatic secretion through the area postrema in unanesthetized rats.

Peptide YY (PYY) inhibits CCK-8-secretin-stimulated pancreatic secretion in vivo. To investigate whether CCK-8-secretin-stimulated pancreatic secretion is mediated through a vago-vagal pathway and whether PYY inhibits this pathway through the area postrema (AP), chronic pancreatic, biliary, and duodenal catheters were implanted in AP-lesioned (APX) or sham-operated rats. The effects of APX on pancreatic secretion stimulated by bethanechol, pancreatic juice diversion (PJD), or CCK-8-secretin, were tested, with and without background PYY infusion, in unanesthetized rats. APX reduced basal pancreatic secretion by 15-20% (P < 0.01). APX had no effect on bethanechol-stimulated secretion and potentiated protein secretion stimulated by PJD (396 vs. 284%) and exogenous CCK-8-secretin. In sham-operated rats, background PYY potently inhibited CCK-8-secretin-stimulated pancreatic fluid (1.8 vs. 48.2%) and protein secretion (3.7 vs. 45.8%) but potentiated fluid (52.9 vs. 43.1%) and protein (132.9 vs. 68.9%) secretion in APX rats. Our findings demonstrate that PYY inhibits CCK-8-secretin-stimulated pancreatic secretion through an AP-dependent mechanism in sham-operated rats. The AP also contributes to basal pancreatic secretion.

Animals↗

PubMed2001

Bone morphogenetic protein-6 reduces ischemia-induced brain damage in rats.

BACKGROUND AND PURPOSE: Bone morphogenetic protein-6 (BMP6) and its receptors are expressed in adult and fetal brain. Receptors for BMP6 are upregulated in adult brain after injury, leading to the suggestion that BMP6 is involved in the physiological response to neuronal injury. The purpose of this study was to determine whether there was a neuroprotective effect of BMP6 in vivo and in vitro. METHODS: Lactate dehydrogenase and microtubule-associated protein-2 (MAP-2) activities were used to determine the protective effect of BMP6 against H(2)O(2) in primary cortical cultures. The neuroprotective effects of BMP6 were also studied in chloral hydrate-anesthetized rats. BMP6 or vehicle was injected into right cerebral cortex before transient right middle cerebral artery (MCA) ligation. Animals were killed for triphenyl-tetrazolium chloride staining, caspase-3 immunoreactivity and enzymatic assays, and TUNEL assay. A subgroup of animals were used for locomotor behavioral assays. RESULTS: Application of H(2)O(2) increased lactate dehydrogenase activity and decreased the density of MAP-2(+) neurons in culture. Both responses were attenuated by BMP6 pretreatment. Complementary in vivo studies showed that pretreatment with BMP6 increased motor performance and generated less cerebral infarction induced by MCA ligation/reperfusion in rats. Pretreatment with BMP6 did not alter cerebral blood flow or physiological parameters. There was decreased ischemia-induced caspase-3 immunoreactivity, caspase-3 enzymatic activity, and density of TUNEL-positive cells in ischemic cortex in BMP6-treated animals. CONCLUSIONS: BMP6 reduces ischemia/reperfusion injury, perhaps by attenuating molecular events underlying apoptosis.

Animals↗

PubMed2001

Nucleotide sequence analysis of a transforming gene isolated from nasopharyngeal carcinoma cell line CNE2: an aberrant human immunoglobulin kappa light chain which lacks variable region.

A transforming gene, designated Tx, was isolated from a human nasopharyngeal carcinoma (NPC) cell line CNE2 by transfection and molecular cloning techniques. The Tx gene was analyzed using computer-based bioinformatics and compared with the known sequences in EMBL and GenBank databases. We found that Tx contains human immunoglobulin kappa light chain constant region, five intact joining regions J1-J5, five recombination signal sequences and an N-segment besides classic regulatory sequences such as TATA boxes, CAAT boxes, poly A signals, etc. Interestingly, Tx also contains several binding sites for nuclear transcription factors such as NF-kappaB, NF-IL6, TFIID, etc. In conclusion, there are only several base pairs mutations or deletions compared with normal Ig K JC gDNA fragment. In all, Tx is an aberrant human immunoglobulin kappa light chain that contains the constant region, five joining regions, which lacks the variable regions.

Genes, Immunoglobulin↗

PubMed2001

The effect of attenuated varicella-zoster virus on replication of HBV.

OBJECTIVE: To observe the effect of attenuated varicella-zoster virus (VZV) on replication of HBV in vitro and vivo. METHODS: The attenuated VZV were inoculated into the ducks infected with DHBV and into the cultural HepG(2) 2.2.15 cells, respectively. DHBV DNA, HBsAg and HBeAg were detected from the duck serum and cell cultural fluid by dot-blot hybridization and EIA. RESULTS: The decline of DHBV DNA in duck serum was found in two dosage groups. Compared with pre-treatment, the level of AD value in 200 pfu/kg group was significantly decreased from 1.17+/-0.29 to 0.59+/-0.45 (10 day after VZV treatment) and 0.21+/-0.21 (5 day after withdrawal of VZV)(t =3.51, 7.54, P<0.001). The level in 400 pfu/kg group was from 0.70+/-0.25 to 0.32+/-0.17 on the 5th day of withdrawal of VZV (t =3.58, P<0.01), respectively after treatment. The inhibitory rates of HBeAg and HBsAg were 61% and 33%, respectively. The effect on HBeAg seems to be more obvious than on HBsAg. CONCLUSIONS: Attenuated VZV could significantly decrease serum DHBV DNA in DHBV-infected ducks and directly inhibit the HBeAg and HBsAg secreted by 2.2.15 cells, suggesting that VZV seems to interfere or inhibit the replication of DHBV.

Animals↗

PubMed2001

Increased hepatic VLDL secretion, lipogenesis, and SREBP-1 expression in the corpulent JCR:LA-cp rat.

The corpulent JCR:LA-cp rat (cp/cp) is a useful model for study of the metabolic consequences of obesity and hyperinsulinemia. To assess the effect of hyperinsulinemia on VLDL secretion in this model, we measured rates of secretion of VLDL in perfused livers derived from cp/cp rats and their lean littermates. Livers of cp/cp rats secreted significantly greater amounts of VLDL triglyceride and apolipoprotein, compared with lean littermates. The content of apoB, apoE, and apoCs in both perfusate and plasma VLDL was greater in the cp/cp rat, as was the apolipoprotein (apo)C, apoA-I, and apoA-IV content of plasma HDL. Triglyceride content was also greater in cp/cp livers, as was hepatic lipogenesis and expression of lipogenic enzymes and sterol regulatory element binding protein-1 (SREBP-1). Hepatic mRNAs for apoE, and apoA-I were higher in livers of cp/cp rats. In contrast, the steady state levels of apoC-II, apoC-III, and apoB mRNAs were unchanged. Thus, livers of obese hyperinsulinemic cp/cp JCR:LA-cp rats secrete a greater number of VLDL particles that are enriched in triglyceride, apoE, and apoC. Greater secretion of VLDL in the cp/cp rat in part results from higher endogenous fatty acid synthesis, which in turn may occur in response to increased expression of the lipogenic enzyme regulator SREBP-1c.

Animals↗

PubMed2001

[Experimental study on the roles of gasmid mite and chigger mite in the transmission of hemorrhagic fever with renal syndrome virus].

OBJECTIVE: To study the roles of gasmid mite and chigger mite in the transmission of hemorrhagic fever with renal syndrome virus (HFRSV). METHODS: Natural gasmid mite, the first generation gasmid mite, chigger mite larvas from rats, free chigger mite larva and nymph were collected and their cells were cultured to study the role of transmission HFRSV. RESULTS: HFRSV was detected from mite cells after cultured for 15 and 20 days. The number of HFRSV and fluorescence intensity detected from the fhird and fourth generation gasmid mite and chigger mite nymph was much more than those from the first, second generation and chigger mite larva. CONCLUSION: Gasmid mite and chigger mite had an important role to play on HFRSV transmission in keeping the natural cycles.

Animals↗

PubMed2001

LMP1 activates NF-kappa B via degradation of I kappa B alpha in nasopharyngeal carcinoma cells.

OBJECTIVE: To elucidate the mechanisms by which Epstein-Barr virus-encoded latent membrane protein 1 activates NF-kappa B in nasopharyngeal carcinoma cells. METHODS: A tetracycline-regulated LMP1-expressing nasopharyngeal carcinoma cell line, Tet-on-LMP1-HNE2, was used as the cell model. The kinetics of the expression of proteins, including LMP1, I kappa B alpha and I kappa B beta, was analyzed by Western blotting. The subcellular localization of NF-kappa B (p65) was detected by indirect immunofluorescence assay. The NF-kappa B transactivity was studied by transient transfection and reporter gene assay. RESULTS: I kappa B alpha was phosphorylated and degraded after the inducible expression of LMP1, although the total protein levels remained stable. The steady-state level of total I kappa B beta protein may have resulted from the initiation of an autoregulation loop after the activation of NF-kappa B. No change in the I kappa B beta level was detected. NF-kappa B (p65) was translocated from the cytoplasm to the nucleus following degradation of I kappa B alpha. After the introduction of the dominant-negative mutant of I kappa B alpha (Del 71) into Tet-on-LMP1-HNE2 cells, both nuclear translocation and transactivation of NF-kappa B induced by LMP1 was significantly inhibited. CONCLUSIONS: The results indicated that in nasopharyngeal carcinoma cells, LMP1 activated NF-kappa B via phosphorylation and degradation of I kappa B alpha, but not I kappa B beta. The dominant-negative mutant of I kappa B alpha (Del 71) could completely inhibit both the nuclear translocation and transactivation of NF-kappa B induced by LMP1.

Biological Transport↗

PubMed2001

[An exponential universal formula and evaluation model of sustainable development for cities].

In order to study an evaluation model of sustainable development for cities, analysis was performed to study the features of indicator system of community, economy and environment. Based on the genetic algorithms optimum, an exponential universal formula of single indicator was proposed. Evaluation model of sustainable development about the coordinative development of community, economy and environment was developed using weighting method combining the general contrast algorithm with analytic hierarchy process for different structure. The evaluation results of sustainable development for examples using this model showed that the exponential formula of single indicator based on parameters optimum and the evaluation model are not only simple and practical, but also comparisonable, realizable and general.

City Planning↗

PubMed2001

[Positive immunoglobulin A expression in human epithelial carcinoma cell lines].

OBJECTIVE: In the present study, we try to further elucidate which class of immunoglobulin is expressed in epithelial carcinoma cell lines. METHODS: Three assays, immunohistochemistry, Western blot and enzyme-linked immunosorbent assay (ELISA) were used to detect the cellular protein extracts and the cultivated supernatant. RESULTS: Seven human epithelial carcinoma cell lines, MCF-7 (human breast carcinoma cell line), SW480 (human colon carcinoma cell line), MGC (human gastric carcinoma cell line), HeLa (human cervical carcinoma cell line), HNE2, CNE1-LMP1 and Tet-on-LMP1-HNE2 (three human nasopharyngeal carcinoma cells) expressed IgA protein in their cellular extracts and cultivated supernatants. CONCLUSION: Immunoglobulin is expressed in epithelium-derived carcinoma cell lines, which is in conflict with the traditional immunoglobulin theory. Our findings imply that the immunoglobulin expressed in epithelial carcinoma cells might play a role in the carcinogenesis of epithelium-derived carcinoma. Understanding the mechanism of immunoglobulin expression by cancer cells may possibly further facilitate the improvement techniques in cancer diagnosis, therapy or the mechanism of carcinogenesis.

Culture Media↗

PubMed2001

[Effects of change of crown contour on health of gingiva].

OBJECTIVE: To study the effects of different excessive crown contours on the health of periodontium. METHODS: A total of 63 posterior teeth of 12 volunteers were randomly divided into three groups and each group was consisted of 21 teeth. The buccal surfaces of the teeth were overcontoured 0.2 mm, 0.5 mm, and 0.8 mm respectively. At the point of 1 week, 4 weeks and 8 weeks, gingival cervical fluid (GCF) were collected, GCF-aspartate aminotransferase (GCF-AST) and GCF-alkaline phosphatase (GCF-ALP) levels were tested and the debris amount was assessed for three groups. RESULTS: The 0.8 mm group presented most amount of GCF, highest level of GCF-AST, GCF-ALP and most debris. The 0.5 mm group was the second. When the excess was 0.2 mm, all indexes showed no statistically significant change. CONCLUSIONS: Excessive crown contour is unfavourable to periodontium health. The more the teeth are excessively contoured, the more they impair periodontium.

Adult↗

PubMed2001

[Anti-virus effect of combination of attenuated measles virus with 3TC on duck hepatitis B model].

OBJECTIVE: To evaluate the anti-virus effect of combination of attenuated measles virus with 3TC on duck hepatitis B model. METHODS: Guanzhou brown spot ducklings infected with DHBV were divided into three groups. Drug treatments including measles vaccine, 3TC and both measles vaccine and 3TC were given in the 13th day after the infection, respectively. Serum samples were obtained from all ducklings before, during and after treatment at different times and stored at -70 degrees C. DHBV DNA was detected by Dot-blot hybridization. RESULTS: Compared with the levels of DHBV DNA before and after treatment, no statistic difference was found in group of 3TC alone. The levels of DHBV DNA were not changed in group of measles vaccine alone in early stage, but decrease of DHBV DNA occurred after stopping treatment (comparison of the levels T13 with before treatment and T13 of positive group, P < 0.01 and P < 0.05, respectively). DHBV DNA level in group of measles vaccine combined with 3TC was obviously lower at 5th day after the treatment than in both measles vaccine and 3TC alone groups at the same time(P < 0.05 and P < 0.01, respectively), and it remained low when the treatment was discontinued. CONCLUSION: Attenuated measles virus combined with 3TC may have early and long-lasting inhibiting effect on the replication of DHBV.

Animals↗

PubMed2001

[Differentiated microcarcinoma of the thyroid gland in 45 cases].

OBJECTIVE: To offer therapeutic management for patients with microcarcinoma of the thyroid gland (TMC). METHOD: Forty-five patients with TMC were treated from 1993, including 10 males and 35 females. Homolateral total thyroidectomy + contralateral subtotal thyroidectomy + homolateral functional neck dissection was taken as routine. RESULT: Among 168 patients with differentiated carcinoma of the thyroid gland, 45 patients were TMC (26.78%). Homolateral metastasis of lymph node presented in 11 (24.44%) of the TMC patients. No operation complications. All patients were followed up. No recurrence, no death. CONCLUSION: The lymph node metastasis appears to be high. Homolateral total thyroidectomy + contralateral subtotal thyroidectomy + homolateral functional neck dissection was effective and essential.

Adult↗

PubMed2001

[Development and evaluation of continuous-flow apparatus with spectrophotometer for fast reaction].

Microprocessor pump drive continuous-flow apparatus with spectrophotometer for study of fast reaction have been developed. The apparatus consists mainly of a microprocessor pump drive, an UV-240 spectrophotometer, a mix cell and the constant temperature facilities. The performance of this apparatus was evaluated by using the model system of Fe(III)-SCN- reaction. The rate constant values of this reaction system are in agreement with some other experimental results. According to the results of the experimental determination, we can see that this apparatus is easy to be operated and shows high precise in measurement. And the apparatus is suitable for kinetic studies of fast reactions whose half-life is in millisecond order.

Autoanalysis↗

PubMed2001

[The effects of long-term domiciliary oxygen therapy on patients of chronic obstructive pulmonary disease with hypoxaemia].

OBJECTIVE: To observe the effects of long-term domiciliary oxygen therapy (LTDOT) on patients of chronic obstructive pulmonary disease (COPD) with hypoxaemia. METHODS: Sixty-one hypoxemic cases with stable COPD were divided into two groups--the LTDOT group of 30 patients and the control group of 31 patents. Before LTDOT and one year or two years later, the lung function test, blood routine, electrocardiography and ultra-echocardiography were tested, the psychological status and quality of life (QOL) were evaluated with the hospital anxiety and depression score and QOL questionnaire respectively. Both groups received routine treatment. In addition,the LTDOT group received oxygen therapy at home with nasal cannula with the oxygen flow of (0.5 - 2.5) L/min for at least 15 hrs every day. RESULTS: Thirteen patients in the LTDOT group died two years later, the mortality rate was 43%; eleven patients in the control group died. In LTDOT group hemoglobin, red blood cell count and hematocrit did not change after one year and two years, the hemoglobin, red blood cell count and hematocrit in the control group did not change after one year but the hemoglobin and red blood cell count increased significantly after two years (P < 0.05); ECG showed that the value of RV1 + SV5 in the LTDOT group remained stable (P > 0.05), which in the control group increased (P < 0.05). After one year and two years, mean pulmonary artery pressure in the LTDOT group declined significantly (P < 0.05). The internal diameter of right ventricle of the heart and the outlet of right ventricle of the heart declined significantly (P < 0.05), but those in the control group increased significantly (P < 0.05). In the LTDOT group, the anxiety and depression scores were significantly improved (P < 0.05) after one year or two years, the total mean score of QOL, general activity score, social activity score, depression and anxiety scores were significantly improved (P < 0.05), but in the control group the anxiety and depression scores did not change (P > 0.05), the total mean score of QOL, social activity score, the anxiety score were significantly worse(P < 0.05). CONCLUSIONS: Long-term domiciliary oxygen therapy could reduce the load of the right heart, improve the patients's psychological status and quality of life.

Aged↗

PubMed2000

Methamphetamine-induced apoptosis is attenuated in the striata of copper-zinc superoxide dismutase transgenic mice.

Administration of methamphetamine caused significant increases in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells, in poly (ADP-ribose) polymerase (PARP) cleavage, as well as in caspase-3 activity in the striata of C57BL/6J mice. In contrast, all these effects were markedly suppressed in the copper-zinc superoxide dismutase transgenic mice. These results indicate that superoxide radicals might be important factors in METH-induced cell death.

Animals↗