[One case of fibroma of the prevertebral spatium of the oral pharyngeal in child].
Explore the source record for details and available documents.
Child, Preschool↗
Biomedical subjects
Hong Zhang
Publications and source records attributed to Hong Zhang.
[Purification and characterization of corresponding antigen recognized by monoclonal antibody 183B2 against ovarian carcinoma].
OBJECTIVE: To purify MAb183B2 corresponding antigen of ovarian carcinomas and study its physical and chemical characteristics. METHODS: The strongest positive samples reacted with MAb183B2 were screened from ovarian cancer ascites with indirect enzyme linked immunosorbent assay (ELISA). Then the antigen was purified from ascitic fluid by affinity chromatography with MAb183B2. Nature of the purified antigen was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot and its reactivity was determined after treatment with NaIO4, trypsin, pronase, neuraminidase, deglycolipid mixture and heating. Two dimensional electrophoresis combined with western blot was then used to isolate and identify the antigen from ovarian cancer cell line SKOV3. RESULTS: The reactivity of the antigen after treated by NaIO4, neuraminidase and deglycolipid mixture was still positive, while it was negative after treated by trypsin, pronase and heating. The antigen proved to be composed of two different subunits of 56,000 and 25,000 by SDS-PAGE, and MAb183B2 could blot the 56,000 band by western blot. The antigen from the SKOV3 cell line displayed microheterogeneity appearing as three spots over a pI range 5.3 approximately 5.8 at 56,000. CONCLUSIONS: The epitope of 183B2-antigen is at its peptide core. The antigen belongs to the Ig super family and might be a new ovarian carcinoma associated antigen.
Antibodies, Monoclonal↗
[The protective effect of MG132 on post-ischemia reperfusion injury of rat livers by activation of nuclear factor kappa B].
Explore the source record for details and available documents.
Animals↗
[Analysis of HRV from brain injury by use of nonextensive relative entropy].
Due to its great clinical significance, brain injury following cardiac arrest (CA) has attracted more attention now. Meanwhile, there are currently no approved real time objective methods used to monitor brain injury following CA. In this study, we adopt the method of nonextensive Kullback-Leibler Entropy in investigating the HRV signals from brain injury and compare the result with that of corresponding EEG analysis. The comparative analysis shows that Kullback-Leibler Entropy can reveal the injury level of brain following CA. And we propose a novel quantitative approach for monitoring brain injury.
Algorithms↗
Persistent organic pollutants control strategy in China.
The development of Persistent Organic Pollutants (POPs) control policy in China in the context of international concerns on POPs was reviewed. The aspects of the Chinese POPs control strategies were analyzed, and compared with those of developed counterparts (e.g. U.S., E.U., Japan). Currently, while the legal framework on POPs management, which complies with international guidelines has been established, it should be improved in the areas of special POPs management, risk assessment, the precautionary principle, life-cycle management and technical support capacity. The analysis of Chinese POPs policy and suggestions for strengthening the science-based decision making capacity are not only useful for Chinese decision-makers, but also a case study for developing world and make a great contribution for the global elimination of POPs to make a toxic-free future.
China↗
Diagnosis and treatment of diffuse axonal injury in 169 patients.
OBJECTIVE: To evaluate current diagnosis and therapeutic effect and outcome of diffuse axonal injury (DAI) in 169 patients. METHODS: The data of 169 DAI patients treated in the Second, Sixth, Eighth and Ninth Hospitals of Shenzhen and Shekou Hospital from January 2001 to January 2005 were collected. The imaging features, classification, GCS (Glasgow coma scale), treatment and outcome of the 169 patients were retrospectively analyzed. RESULTS: The simpler the imaging features, the closer the focus of DAI to the periphery of hemisphere and the higher the GCS score, the better the prognoses of DAI patients will be. CONCLUSIONS: The prognoses of DAI patients are closely related to the imaging features and classification, GCS and clinical treatment.
Journal Article↗
[The corn seedlings are affected by the heavy metal Pb2+].
The corn seedlings in hydroponic culture are treated with the lead acetate solutions of various concentrations, the content of Pb2+ in the roots, stems and leafs of the corns at 10th day, 20th day and 30th day is measured. The analyzing conclusions are that the contents of Pb2+ in the corns display a sequence of root>leaf>stem, the contains of chlorophyll in corns fall off, the raising of Pb2+ in solutions, the membrane penetrability of the corns increased along a sequence of root>leaf>stem, and the harmful rate of Pb2+ display a sequence of root>leaf>stem in corns. The data of the study gives some references for the further researches of the crops, relating the endurance and the distributing of corns with Pb2+.
Cell Membrane Permeability↗
Hsp90 activation and cell cycle regulation.
The widely-expressed molecular chaperone heat shock protein 90 (Hsp90) regulates several important cellular processes via its' repertoire of 'client' proteins. Signal transduction pathways controlled by Hsp90 contribute to all major components of the malignant phenotype, so Hsp90 inhibitors are under investigation as anticancer agents. Since Hsp90 is also expressed at high levels in many normal tissues, it was unclear why Hsp90 inhibitors such as 17-allylamino-geldanamycin (17-AAG) have selective antitumor activity in animals and are well tolerated clinically. Recent findings indicate that Hsp90 is largely latent in unstressed normal cells, but tumor Hsp90 becomes completely utilized during malignant progression, resulting in an activation-dependent conformational shift that radically increases 17-AAG binding affinity in cancer cells. In this article, the implications of this discovery are discussed, with particular reference to cell cycle regulation in normal and malignant cells, and the consequences of inducing cell cycle arrest with Hsp90 inhibitors.
Cell Cycle↗
Circulating endothelial progenitor cells in multiple myeloma: implications and significance.
Angiogenesis governs the progression of multiple myeloma (MM). Circulating endothelial cells (CECs) contribute to angiogenesis and comprise mature ECs and endothelial progenitor cells (EPCs). The present study sought to characterize CECs and their relation to disease activity and therapeutic response in 31 consecutive patients with MM. CECs, identified as CD34(+)/CD146(+)/CD105(+)/CD11b(-) cells, were 6-fold higher in patients compared to controls and correlated positively with serum M protein and beta(2)-microglobulin. Circulating EPCs displayed late colony formation/outgrowth and capillary-like network formation on matrigel; these processes were inhibited after effective thalidomide treatment. Co-expression of vascular endothelial growth factor receptor-2 (KDR) and CD133 characterized EPCs in MM, and KDR mRNA elevations correlated with M protein levels. In vitro exposure of ECs to thalidomide or its derivative CC-5013 inhibited gene expression of the receptors for transforming growth factor-beta and thrombin. Thus, elevated levels of CECs and EPCs covary with disease activity and response to thalidomide, underscoring the angiogenic aspect of MM and suggesting that angioblastlike EPCs are a pathogenic biomarker and a rational treatment target in MM. The results also highlight the anti-angiogenic properties of thalidomide and CC-5013 and further elucidate possible mechanisms of their effectiveness against MM. (Blood. 2005;105:3286-3294).
Adult↗
APOE4 protects the cognitive development in children with heavy diarrhea burdens in Northeast Brazil.
Polymorphisms in the apolipoprotein E (APOE) have constituted the major rationale to identify potential risk groups for developing late-onset Alzheimer's disease and help to predict recovery of cognitive function after brain injury. However, the APOE impact on cognitive development in children living in poor areas of the developing world, where we have discovered profound significant associations of early childhood diarrhea (at 0-2 y) with lasting impairments of growth, cognition, and school performance, is not known. Therefore, we conducted APOE genotyping in 72 Brazilian shantytown children under active surveillance since birth, using purified DNA extracted from buccal cell samples. We found a high frequency of APOE4 alleles (18% versus 9-11% expected) in children with lower diarrhea burdens. When we examined the children who experienced the heavier diarrhea burdens (greater than or equal to the median of seven illnesses in the first 2 y of life), those with APOE4 did significantly better in the coding subtest (p=0.01) when compared with APOE4-negative children with similar diarrhea burdens. Positive correlations between the APOE4 occurrence and coding scores remained, even after adjusting for family income, maternal education, and breast-feeding. Moreover, the APOE4-positive group, under heavy burdens of diarrhea, had preserved semantic fluency and the mean difference in fluency scores, p=0.025, a standardized coefficient for disproportional verbal fluency impairment. Our findings show that APOE4 is relatively common in favela children and suggest a protective role of the APOE4 allele in children with a history of heavy burdens of diarrhea in their first 2 y of life.
Alleles↗
Discovery of 4-aryl-4H-chromenes as a new series of apoptosis inducers using a cell- and caspase-based high-throughput screening assay. 1. Structure-activity relationships of the 4-aryl group.
By applying a novel cell- and caspase-based HTS assay, 2-amino-3-cyano-7-(dimethylamino)-4-(3-methoxy-4,5-methylenedioxyphenyl)-4H-chromene (1a) has been identified as a potent apoptosis inducer. Compound 1a was found to induce nuclear fragmentation and PARP cleavage, as well as to arrest cells at the G(2)/M stage and to induce apoptosis as determined by the flow cytometry analysis assay in multiple human cell lines (e.g. Jurkat, T47D). Through structure-activity relationship (SAR) studies of the 4-aryl group, a 4- and 7-fold increase in potency was obtained from the screening hit 1a to the lead compounds 2-amino-4-(3-bromo-4,5-dimethoxyphenyl)-3-cyano-7-(dimethylamino)-4H-chromene (1c) and 2-amino-3-cyano-7-(dimethylamino)-4-(5-methyl-3-pyridyl)-4H-chromene (4e), with an EC(50) of 19 and 11 nM in the caspase activation assay in T47D breast cancer cells, respectively. The 2-amino-4-aryl-3-cyano-7-(dimethylamino)-4H-chromenes also were found to be highly active in the growth inhibition MTT assay, with GI(50) values in the low nanomolar range for compound 1c. Significantly, compound 1c was found to have a GI(50) value of 2 nM in the paclitaxel resistant, p-glycoprotein overexpressed, MES-SA/DX5 tumor cells. Functionally, compound 1c was found to be a potent inhibitor of tubulin polymerization and to effectively inhibit the binding of colchicine to tubulin. These results confirm that the cell-based caspase activation assay is a powerful tool for the discovery of potent apoptosis inducers and suggest that the 4-aryl-4H-chromenes have the potential to be developed into future anticancer agents.
Antineoplastic Agents↗
Smurf2 up-regulation activates telomere-dependent senescence.
Progressive telomere shortening activates replicative senescence, which prevents somatic cells from being propagated indefinitely in culture. The limitation of proliferative capacity imposed by replicative senescence is thought to contribute to both organismal aging and the prevention of tumor development. Here we report that up-regulation of Smurf2, an E3 ubiquitin ligase previously implicated in TGF-beta signaling, is a specific consequence of telomere attrition in human fibroblasts and that such up-regulation is sufficient to produce the senescence phenotype. Adventitious production of the Smurf2 protein in early passage fibroblasts at the same physiological level observed during telomere-mediated senescence resulted in proliferative arrest in a viable state, morphological and biochemical alterations characteristic of senescence, acquisition of senescence-specific alterations in gene expression, and reversal of cellular immortalization by telomerase. We show that the senescence-inducing actions of Smurf2 occur in the absence of detectable DNA damage or stress response, that Smurf2's effects require a novel function distinct from its E3 activity, that Smurf2 recruits the Rb and p53 pathways for senescence induction, and that while p21 is elevated by Smurf2, Smurf2-mediated senescence is independent of p21. Smurf2 is the first gene found to be both up-regulated by telomere attrition and sufficient to induce senescence.
Blotting, Northern↗
Guidance of myocardial patterning in cardiac development by Sema6D reverse signalling.
Cardiac chamber formation involves dynamic changes in myocardial organization, including trabeculation and expansion of the compact layer. The positional cues that regulate myocardial patterning, however, remain unclear. Through ligation of the Plexin-A1 receptor, the transmembrane-type semaphorin Sema6D regulates endocardial cell migration. Here, we demonstrate that knockdown of either Sema6D or Plexin-A1 leads to the generation of a small, thin ventricular compact layer and to defective trabeculation. In the heart, expression of the Plexin-A1 extracellular domain alone can rescue the defective trabeculation induced by suppression of Plexin-A1, but not that resulting from defective Sema6D expression. This indicates that reverse signalling by Sema6D occurs within the myocardium. In a ligand-dependent manner, Abl kinase is recruited to the cytoplasmic tail of Sema6D and activated, resulting in phosphorylation of Enabled and dissociation from Sema6D. Constitutive activation of Sema6D signalling enhances the migration of myocardial cells into the trabeculae, whereas inhibition arrests cells within the compact layer. Thus, Sema6D coordinates both compact-layer expansion and trabeculation, functioning as both a ligand and a receptor for Plexin-A1.
Animals↗
The inhibitory receptor PIR-B negatively regulates neutrophil and macrophage integrin signaling.
The Ig-like receptor family member, PIR-B, has been shown to play an inhibitory role in receptor signaling within B cells, mast cells, and dendritic cells. As it has been implicated in integrin-mediated responses, we investigated the effect of loss of the PIR-B protein on integrin-mediated signaling in primary murine myeloid cells. The pir-b-/- neutrophils displayed enhanced respiratory burst, secondary granule release, and a hyperadhesive phenotype when plated on surfaces coated with either extracellular matrix proteins or cellular adhesion molecules in the presence or absence of the soluble inflammatory agonist TNF-alpha. The pir-b-/- and wild-type cells responded equivalently when stimulated with TNF-alpha in suspension, indicating that the hyperresponsive phenotype of the pir-b-/- cells during adhesion was due to enhanced integrin signaling. Both wild-type and pir-b-/- neutrophils expressed similar levels of integrin subunits. Primary bone marrow-derived macrophages from pir-b-/- mice were also hyperadhesive and spread more rapidly than wild-type cells following plating on surfaces that cross-linked cellular beta2 integrins. Biochemical analysis of macrophages from pir-b-/- mice revealed enhanced phosphorylation and activation of proteins involved in integrin signaling. These observations point to a nonredundant role for PIR-B in the regulation of leukocyte integrin signaling.
Animals↗
Structural analysis of Pseudomonas 1-aminocyclopropane-1-carboxylate deaminase complexes: insight into the mechanism of a unique pyridoxal-5'-phosphate dependent cyclopropane ring-opening reaction.
1-Aminocyclopropane-1-carboxylate (ACC) deaminase is a pyridoxal 5'-phosphate (PLP) dependent enzyme catalyzing the opening of the cyclopropane ring of ACC to give alpha-ketobutyric acid and ammonia as the products. This ring cleavage reaction is unusual because the substrate, ACC, contains no abstractable alpha-proton and the carboxyl group is retained in the product. How the reaction is initiated to generate an alpha-carbanionic intermediate, which is the common entry for most PLP-dependent reactions, is not obvious. To gain insight into this unusual ring-opening reaction, we have solved the crystal structures of ACC deaminase from Pseudomonas sp. ACP in complex with substrate ACC, an inhibitor, 1-aminocyclopropane-1-phosphonate (ACP), the product alpha-ketobutyrate, and two d-amino acids. Several notable observations of these structural studies include the following: (1) a typically elusive gem-diamine intermediate is trapped in the enzyme complex with ACC or ACP; (2) Tyr294 is in close proximity (3.0 A) to the pro-S methylene carbon of ACC in the gem-diamine complexes, implicating a direct role of this residue in the ring-opening reaction; (3) Tyr294 may also be responsible for the abstraction of the alpha-proton from d-amino acids, a prelude to the subsequent deamination reaction; (4) the steric hindrance precludes accessibility of active site functional groups to the l-amino acid substrates and may account for the stereospecificity of this enzyme toward d-amino acids. These structural data provide evidence favoring a mechanism in which the ring cleavage is induced by a nucleophilic attack at the pro-S beta-methylene carbon of ACC, with Tyr294 as the nucleophile. However, these observations are also consistent with an alternative mechanistic possibility in which the ring opening is acid-catalyzed and may be facilitated by charge relay through PLP, where Tyr294 functions as a general acid. The results of mutagenesis studies corroborated the assigned critical role for Tyr294 in the catalysis.
Binding Sites↗
[The inhibitory effects of angiostatin on retinal neovascularization induced by oxygen].
OBJECTIVE: To observe the inhibitory effects of angiostatin on microvascular endothelial cells of mouse retina and test the efficacy of native angiostatin in suppressing experimental retinal neovascularization induced by oxygen. METHODS: Angiostatin was purified with L-lysine Sepharose 4B from human plasma. The primary microvascular endothelial cells from rat retina were cultured. Microvascular endothelial cells growth inhibition assay was carried out with MTT method. Mouse models of hyperoxia-induced ischemic retinopathy were established. Angiostatin or normal saline (NS) were injected into the vitreous in 5 groups: normal, control and various doses. The nuclei of new vessel buds extending from the retina into the vitreous in different groups were counted and compared under the light microscope. RESULTS: Angiostatin could inhibit the growth of microvascular endothelial cells from rat retina in vitro. There were plenty of new vessel buds in the eyes of all mice in hyperoxic condition. The number of the nuclei of new vesselbuds in the murine eyes with injection of angiostatin. They were reduced by 42% (P < 0.01), 57% (P < 0.01) and 82% (P < 0.01) respectively. CONCLUSION: Angiostatin can powerfully inhibit growth of microvascular endothelial cells. The proliferation of retinal vessel may be suppressed by using angiostatin.
Angiogenesis Inhibitors↗
Drift of rigidly rotating spirals under periodic and noisy illuminations.
Under the weak deformation approximation, the motion of rigidly rotating spirals induced by periodic and noisy illuminations are investigated analytically. We derive an approximate but explicit formula of the spiral drift velocity directly from the original reaction-diffusion equation. With this formula we are able to explain the main features in the periodic and noisy illuminations induced spiral drift problems. Numerical computations of the Oregonator model are carried out as well, and they agree with the main qualitative conclusions of our analytical results.
Journal Article↗
[Serum osteoprotegrin and serum bone gamma-carboxyglutamine acid-containing protein are correlated with bone mineral density in normal women].
OBJECTIVE: To study the relationships of serum osteoprotegrin (sOPG), serum bone gamma-carboxyglutamine acid-containing protein (sBGP), and urine deoxypyridinoline (uDPD)/creatinine (Cr) with age and bone mineral density (BMD) in women. METHODS: ELISA was used to examine the sOPG, sBGP, and uDPD/Cr of 672 female volunteers aged 20-80. The BMD (QDR4500A) value of the anteroposterior lumbar spine and femoral neck were measured by DXA. RESULTS: (1) The levels of sOPG, sBGP, and uDPD/Cr in the age group of 30-39 were 2.8 pmol/L +/- 1.4 pmol/L, 5 microg/L +/- 3 microg/L, and 4.9 nmol/mmol +/- 2.5 nmol/mmol respectively, all significantly lower than those in the age groups 40-49, 50-59, and 60-69 (all P < 0.05). (2) In the age group 40-49, the values of sOPG, sBGP, and uDPD in menopausal subjects were significantly higher than those of the non-menopausal subjects (5.7 pmol/L +/- 3.1 pmol/L vs 3.4 pmol/L +/- 2.0 pmol/L, 11 microg/L +/- 5 microg/L vs 6 microg/L +/- 3 microg/L, and 6.9 nmol/mmol +/- 3.3 nmol/mmol vs 5.2 nmol/mmol +/- 3.9 nmol/mmol, all P < 0.001). (3) Age was positively correlated with sOPG, sBGP, uDPD/Cr, and BMD of anteroposterior lumbar spine and femoral neck (r = 0.130, 0.355, 0.106, -0.600, -0.545; P < 0.01). sOPG and sBGP were negatively correlated to anteroposterior lumbar spine BMD (r = -0.183, -0.108, P < 0.01; and r = -0.541, -0.441, P < 0.001). sOPG was positively correlated with sBGP and uDPD/Cr (r = 0.216 and 0.083; both P < 0.05). CONCLUSION: sOPG, sBGP, and uDPD/Cr can be used as sensitive markers to determine the bone turnover status, which is changeable with age, and menopausal status in women, and predict the bone lose prior to BMD determination by DXA.
1-Carboxyglutamic Acid↗