Assignment of the Zona pellucida 3 receptor (Zp3r) gene to mouse chromosome 1E-F by fluorescence in situ hybridization and confirmation by genetic mapping.
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Animals↗
Biomedical subjects
X Deng
Publications and source records attributed to X Deng.
Effect of sterilization on the physical and structural characteristics of polyhydroxyoctanoate (PHO).
The present study examined the potential applicability of poly(beta-hydroxy octanoate) (PHO), a bacterial polyester, as a candidate for biomaterial applications, by investigating the effect of sterilization on the physical and structural characteristics of PHO. PHO-cast films were sterilized by either ethylene oxide (EO) gas at 38 degrees C or gamma radiation (2.5 Mrad) in air at room temperature. The physical characteristics of the EO and gamma-sterilized PHO were determined by scanning electron microscopy (SEM) and tensile strength analyses. In addition, various analytical methods were used to detect modifications in the chemical and morphological structure of PHO, namely, electron spectroscopy for chemical analysis (ESCA), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), and size exclusion chromatography (SEC). The results show that EO sterilization did not modify the chemical and physical characteristics of PHO, however, significant modifications in both the structural and tensile properties were observed with gamma-sterilized PHO. These changes accounted for decreases in both the weight average, number average and melting temperature, and increases in the heat of fusion and tensile strength. No residual EO was detected following sterilization as revealed by head-space chromatography. The physical and structural properties of PHO were shown to be well preserved following EO sterilization, whereas gamma radiation caused random chain scission and physical cross-linking, a frequent phenomenon observed with organic polymers.
Bacteria↗
Hydrolytic and enzymatic incubation of polyhydroxyoctanoate (PHO): a short-term in vitro study of a degradable bacterial polyester.
The present study examined the degradation behaviour of poly(beta-hydroxy octanoate) (PHO), a bacterial poly(beta-hydroxy alkanoate), following incubation under hydrolytic or enzymatic conditions in vitro. Solution-cast PHO films were incubated in a citrate buffer solution with and without acid phosphatase and in an acetate buffer with and without beta-glucuronidase for periods ranging from 7 to 60 days. The physical characterization of the PHO films was analyzed by SEM and tensile strength studies. In addition, various analytical methods were used to detect modifications in the chemical and morphological structure of the PHO, namely, ESCA, FTIR, DSC, X-ray diffraction, and SEC. The results indicate that the enzymatic conditions selected in the present study induced no significant surface morphological or chemical modifications, and no significant weight loss was observed after 60 days of incubation. However, as revealed by weight average molecular weight Mw and number average molecular weight Mn decreases, changes in the bulk structure of the PHO were observed with acid phosphatase at 28 and 60 days, in contrast to smaller Mw and Mn decreases recorded in both the buffers and the beta-glucuronidase. The tensile properties had decreased following incubation, yet showed no difference under all of the selected conditions. With no weight loss or surface changes, the PHO films incubated in acid phosphatase showed only a chemical hydrolytic process characterized by Mw and Mn decreases with time of incubation. The present study demonstrated that the degradation of PHO films is one of slow, chemical hydrolysis only, perhaps requiring several months of incubation. The hydrophobic nature of the long alkyl pendent chain in PHO may be responsible for this slow process. The inability of enzymes to degrade PHO may be attributed to the latter's poor adsorption capacity, due to its hydrophobic nature, and to a lack of specificity in the catalytic activity of these enzymes.
Acid Phosphatase↗
Treatment with lexipafant ameliorates the severity of pancreatic microvascular endothelial barrier dysfunction in rats with acute hemorrhagic pancreatitis.
CONCLUSION: Treatment with lexipafant reduced the severity of pancreatitis-associated endothelial barrier compromise, also associated with a decrease in systemic concentrations of interleukin (IL) 1. Thus, the present findings imply that platelet-activating factor (PAF) may play an important role in the pathogenesis of pancreatic endothelial dysfunction by signaling and triggering the production and release of certain cytokines. BACKGROUND: Pancreatic capillary endothelial barrier dysfunction is an initial and characteristic feature of acute pancreatic injury and pancreatitis. PAF, a proinflammatory mediator and an intercellular signaling substance, has been considered to be involved in the inflammatory reaction and the systemic endothelial dysfunction of acute pancreatitis. METHODS: The development of pancreatic capillary endothelial barrier dysfunction was monitored by tissue edema and exudation of plasma albumin into the interstitium, 3 and 12 h after induction of acute pancreatitis by intraductal infusion of 5% sodium taurodeoxycholate in rats. Pancreatic leukocyte recruitment was reflected by measuring myeloperoxidase activity. Serum levels of IL-1 beta and IL-6 were determined by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Pretreatment with lexipafant, a potent PAF receptor antagonist, significantly reduced the pancreatitis-induced increase in pancreatic endothelial barrier dysfunction, pancreatic leukocyte recruitment and serum levels of IL-1 beta, although a difference persisted between animals with sham operation and pancreatitis.
Acute Disease↗
Mechanical characteristics of the canine thoracic duct: what are the driving forces of the lymph flow?
This study is designed to better understand the mode of lymph transport, particularly through the extrinsic pumping by external compression of the lymph vessel. The pressure-diameter relationship of lymphatic segments isolated from the canine thoracic duct was examined using a laser optical micrometer measurement system. Results revealed that the thoracic duct displayed a high extensibility or compliance in the physiological pressure range, yet became progressively less so with increasing internal pressure. The calculated incremental circumferential modulus of the thoracic duct under physiological pressure (range of 2 to 6 cm H2O) showed values ranging from 1.2 x 10(4) to 3.61 x 10(5) dyn/cm2. At a pressure of 35 cm H2O, the modulus reached a limiting value of approximately 6.0 x 10(6) dyn/cm2. In the physiological pressure range, the relative wall thickness (h/R0) of the canine thoracic duct was approximately 3.5%, which was much lower than that reported for canine arterial segments and similar in value to that of the canine jugular vein. In conclusion, the pressure-diameter curve of the canine thoracic duct was shown to resemble that of venous vessels. However, the circumferential elastic modulus of the thoracic duct wall was lower than the moduli of veins, proving that lymphatics are more compliant than veins. This suggests lymph flow in the thoracic duct may be better promoted by external compression of the lymphatic vessel.
Animals↗
[Bone mineral density investigation of normal women in Changsha by dual energy X-ray absorptiometry and its clinical implications].
OBJECTIVE: To establish reference values of bone mineral density (BMD) in normal female. METHODS: 1,257 healthy women aged 15 to 96 years from Changsha were involved. BMD measurements were taken at various skeletal sites (anteroposterior and lateral lumbar spine, hip and forearm) by Hologic QDR4500A dual energy X-ray absorptiometry (DEXA). RESULTS: (1) The BMD value of Ward's triangle and major trochanter peaked early at the age of 20-24, while that of the one-third mid-distal forearm peaked late at 40-44 years old. (2) Significant loss of BMD (-6.4%, -10.8%) was found at lateral lumbar spine and Ward's triangle respectively before age 45. The acceleration of bone loss at various sites appeared both at age 45-64 and 75 with the maximum magnitude at Ward's triangle (64.4%) and minimum at one-third mid-distal forearm (29.0%-34.3%). (3) The rank of osteoporosis detection rate from high to low after age 40 was lateral lumbar spine (27.8%), forearm, Ward's triangle and anteroposterior lumbar spine (10.5%) and femur neck or major trochanter (10.1%). CONCLUSION: BMD measurements are necessary in women after age of 40 years. The most sensitive sites for detecting osteoporosis are lateral lumbar spine, Ward's triangle and forearm.
Absorptiometry, Photon↗
[Clinical uses of transvaginal ultrasonography in endometrial surveillance].
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Endometrial Neoplasms↗
Preliminary study on application of artificial neural network to the diagnosis of Alzheimer's disease with magnetic resonance imaging.
OBJECTIVE: Artificial neural network is first used in the measurement study of brain of Alzheimer's disease using MRI, and a completely new pattern discriminating method is adopted, so as to take advantage of MRI to diagnose and identify AD patients. METHODS: 12 patients with probable AD (aged 65.33 +/- 8.62 years) and 36 normal controls matched with age and gender (aged 65.81 +/- 74.37 years) were studied. MRI are performed on Siemens Magnetom IMPACT 1.0 T; eight interesting brain structures including sixteen regions (left and right) indices are measured and studied; SPSS software and BP network software made by authors respectively were used to process and analyze the measured data. RESULTS: Using artificial neural network to the same regions and data, both the sensitivity and accuracy were found higher than using the traditional discrimination function analysis method; the indices of amygdala, hippocampus, parahippocampal gyrus, temporal lobe, and temporal horn, these five structures could completely differentiate AD from normal controls; new cases were successfully diagnosed. CONCLUSIONS: Artificial neural network combining with MRI is probable to become a useful and reliable clinical tool to diagnose AD patients.
Aged↗
[A study on immunogenicity and safety of bivalent inactivated vaccine against hemorrhagic fever with renal syndrome].
OBJECTIVE: To study side effects and effectiveness of bivalent inactivated vaccine against hemorrhagic fever with renal syndrome in population of a randomized controlled field trial. METHODS: Serum indirect immunofluorescent antibody in 167 persons and neutralization antibody (types I and II) in 69 persons, who received three-dose vaccine, were determined two weeks after immunization, and side effects in 657 vaccinees were observed within 72 houses after immunization. RESULTS: Serum positive conversion rate of indirect immunofluorescent antibody was 99.04% (166/167) with GMT of 24.51 +/- 2.06. Serum positive conversion rate of neutralization antibody was 100% (69/69), 91.30% (63/69) for types I and 88.41% (61/69) for type II, respectively. GMTs for type I and II neutralization antibody were 18.27 +/- 2.21 and 12.47 +/- 2.16, respectively. Side effects at local site vaccinated of the body and temperature rising could be seen in 1.48% and 0.36% of the vaccinees, respectively. No severe side effect and abnormal reaction was found in vaccinees on the field. CONCLUSION: Immune response to bivalent inactivated vaccine against hemorrhagic fever with renal syndrome was satisfactory with slight side effect.
Adolescent↗
[Internal fixation for zygomatic arch fracture with super-high molecular weight poly D, L-lactic acid mini-plates and screws: a study in dogs].
OBJECTIVE: To investigate the internal fixation effects of super high molecular weight (Mv = 6.0 x 10(5) kD) poly D, L-lactic acid(PDLLA) mini-plates and screws. METHODS: 10 dogs were utilized in this experiment with the self-contrast study method, comparing with the titanium mini-plates and screws. RESULTS: The mechanical properties of the PDLLA mini-plates and screws appeared to be sufficient to enable undisturbed healing of depressed zygomatic arch fracture. CONCLUSION: The good fixation effect of PDLLA mini-plates and screws was as same as that of the titanium mini-plates and screws without the need of secondary operation.
Animals↗
[Tissue reaction and degradation of super-high molecular weight poly D, L-lactic acid mini-plates and screws: an animal experiment].
OBJECTIVE: To investigate the tissue reaction and degradation processes of the super-high molecular weight(Mv = 6.0 x 10(5) kD) poly D, L-lactic acid(PDLLA) mini-plates and screws through the internal fixation for zygomatic arch fracture. METHODS: It was carried out by the self-contrast study method and comparing with the titanium mini-plates and screws. RESULTS: There was no side-effects on bone healing. The reaction of soft and hard tissues to PDLLA mini-plates and screws was similar to that of the titanium mini-plates and screws. No complication had been seen with the use of PDLLA mini-plates and screws, including infection, foreign body reaction and underlying osteolysis. The PDLLA devices had no changes in shape after 3 months, and then became the grains in different sizes after 6 months, and were completely resorbed within 12 months in vivo. CONCLUSION: The super-high molecular weight PDLLA mini-plates and screws has good biocompatibility and proper degradation time. It is safe and effective to use the mini-plates and screws made of the super-high molecular weight PDLLA for internal fixation of bone.
Animals↗
[Studies on biosorption of Pb2+ by Phanerochaete chrysosporium].
The biosorption of Pb2+ from solution by Phanerochaete chrysosporium was studied. The effects on biosorption capacity of pH, Pb2+ concentration in solution, co-ion and temperature, time have been examined. The adsorption capacity was compared among the biomass harvested at various growth stages. Pretreatment of biomass by NaOH solution improved its adsorption capacity. The uptake could reach 108.4 mg/g at optimal conditions of biosorption using pretreated biomass.
Absorption↗
[Establishment of a rabbit model of Acanthamoeba keratitis].
AIM: To establish an animal model of Acanthamoeba keratitis. METHODS: Six New Zealand white rabbits were each injected intrastromally with Acanthamoeba suspension 3 days after subconjunctival injection with dexamethasone. RESULTS: All of the 6 rabbits developed keratitis. Acanthamoeba protozoa were identified by the methods of corneal scraping with 10% potassium hydroxide wet mount examined under microscope, corneal protozoa culture and pathological section examination. CONCLUSION: A rabbit model of Acanthamoeba keratitis was established.
Acanthamoeba Keratitis↗
[Survey of toxoplasma infection in fertile age women and children in Urumqi city].
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Adolescent↗
[Morphological and histological studies of Herba Boschniakiae].
This paper deals with the morphological characters of the plants and drugs, and the histological characters of the stems of Herba Boschniakiae (Boschniakia rossica). This results provide authentic methods for the identification of Herba Boschniakiae.
Drug Contamination↗
Differential responsiveness to autocrine and exogenous transforming growth factor (TGF) beta1 in cells with nonfunctional TGF-beta receptor type III.
The two major intestinal epithelial cell lineages are columnar fluid-absorbing cells and mucin-producing goblet cells. High levels of transforming growth factor (TGF) beta1 are found surrounding postmitotic cells in the colonic crypt, suggesting that TGF-beta1 mediates the maturation and growth inhibition of both epithelial cell types. However, we now show that the injection of recombinant TGF-beta1 into mice leads to an enrichment of goblet cells, indicating that these normal epithelial cells are resistant to TGF-beta1. In support of this interpretation, each of two independently isolated cell lines modeling normal colon goblet cells was also growth resistant to exogenous TGF-beta1 but made levels of TGF-beta receptor (TbetaR) I, TbetaRII, and TbetaIII mRNA and protein equal to those made by two TGF-beta1-sensitive cell lines. No mutations were found in the alk5 or alk2 forms of TbetaRI or in TbetaRII; these receptors were found on the cell surface, although they could not bind 125I-labeled TGF-beta1. TbetaRIII binds TGF-beta1, concentrates it, and presents it to TbetaRII. The major TbetaRIII form, betaglycan, did not undergo normal posttranslational modification in either of the goblet cell lines and could not bind 125I-labeled TGF-beta1; thus, it was nonfunctional. TGF-beta resistance was overcome by raising TGF-beta1 levels 100-fold, at which point TbetaRII could bind TGF-beta1. Signaling initiated by these higher TGF-beta1 levels was blocked by the expression of dominant negative TbetaRII, demonstrating that TbetaRII and TbetaRI were functional. Cells resistant to exogenous TGF-beta1 maintained functional cell surface TbetaRI and TbetaRII to mediate responses to autocrine TGF-beta1, which controlled the maturation of the adhesion protein integrin beta1. Expression of dominant negative TbetaRII in goblet cells greatly inhibited the conversion of the beta1 integrin from its precursor to its mature form. Thus, in normal intestinal epithelial goblet cells, TbetaRI and TbetaRII can respond to autocrine but not exogenous TGF-beta without the participation of TbetaRIII. Absorptive epithelial cells are growth inhibited by TGF-beta1 both in vivo and in vitro; therefore, the loss of functional TbetaRIIIs on goblet cells allows differential regulation of the two major intestinal epithelial cell types.
Activin Receptors, Type I↗
Reversible phosphorylation of Bcl2 following interleukin 3 or bryostatin 1 is mediated by direct interaction with protein phosphatase 2A.
Interleukin 3 (IL-3) stimulates the net growth of murine factor-dependent NSF/N1.H7 and FDC-P1/ER myeloid cells by stimulating proliferation and suppressing apoptosis. Recently, we discovered that Bcl2 is phosphorylated at an evolutionarily conserved serine residue (Ser70) after treatment with the survival agonists IL-3 or bryostatin 1, a potent activator of protein kinase (Ito, T., Deng, X., Carr, B., and May, W. S. (1997) J. Biol. Chem. 272, 11671-11673). In addition, an intact Ser70 was found to be required for Bcl2's ability to suppress apoptosis after IL-3 withdrawal or toxic chemotherapy. We now show that phosphorylation of Bcl2 occurs rapidly after the addition of agonist to IL-3-deprived cells and can be reversed by the action of an okadaic acid (OA)-sensitive phosphatase. A role for protein phosphatase (PP) 2A as the Bcl2 regulatory phosphatase is supported by several observations: 1) dephosphorylation of Bcl2 is blocked by OA, a potent PP1 and PP2A inhibitor; 2) intracellular PP2A, but not PP1, co-localizes with Bcl2; 3) the purified PP2Ac catalytic subunit directly dephosphorylates Bcl2 in vitro in an OA-sensitive manner; 4) the purified PP2Ac catalytic subunit preferentially dephosphorylates Bcl2 in vitro compared with PP1 and PP2B; 5) reciprocal immunoprecipitation studies indicate a direct interaction between PP2A and hemagglutinin (HA)-Bcl2; and 6) treatment of factor-deprived cells with bryostatin 1 dramatically increases the association between PP2A and Bcl2. Increased association between Bcl2 and PP2A occurs 15 min after agonist stimulation when Bcl2 phosphorylation has peaked and immediately before dephosphorylation. An agonist-induced increased association of PP2A and Bcl2 fails to occur in cells expressing the inactive, phosphorylation-negative S70A Bcl2 mutant, which indicates that an intact Ser70 site is necessary and sufficient for the interaction to occur. Functional phosphorylation of Bcl2 at Ser70 is proposed to be a dynamic process regulated by the sequential action of an agonist-activated Bcl2 kinase and PP2A.
Animals↗
Chemokines and their role in tumor growth and metastasis.
Chemokines are a superfamily of pro-inflammatory polypeptide cytokines that selectively attract and activate different cell types. Many patho-physiological conditions require the participation of chemokines, including inflammation, infection, tissue injury, allergy, cardiovascular diseases, as well as malignant tumors. Chemokines activate cells through their binding to shared or unique cell surface receptors which belong to the seven-transmembrane, G-protein-coupled Rhodopsin superfamily. The role of chemokines in malignant tumors is complex: while some chemokines may enhance innate or specific host immunity against tumor implantation, others may favor tumor growth and metastasis by promoting tumor cell proliferation, migration or neovascularization in tumor tissue. In this review, the authors summarize some of the recent advances in chemokine research and emphasis is made on the effect of chemokines in tumor growth and metastasis.
Animals↗