Expression and deletion analysis of EcoRII endonuclease and methylase gene

OBJECTIVE

To clone complete EcoRII restriction endonuclease gene (ecoRIIR) and methyltransferase gene (ecoRIIM) in one vector and to analyze the coordinating expression of this whole R-M system.

METHODS

Unidirectional deletion subclones were constructed with ExoIII. ecoRIIR/ M genes were preliminarily located in the cloned fragment according to the enzyme activities of subclones. Exact deletion sites were determined by sequencing, and transcriptional start sites were determined by S1 mapping.

RESULTS

The DNA fragment which was cloned into pBluescript SK + contained intact ecoRIIR gene and ecoRIIM gene, and two transcriptional start sites of ecoRIIR gene were determined. 132bp to 458bp from 3'end of ecoRIIR gene are indispensable to enzyme activities and deletion of 202bp from 3' end of ecoRIIM gene made enzyme lose the capability in DNA protection to resist specific cut with EcoRII endonuclease (EcoRII. R). Deletion of the coding and flanking sequences of one gene did not affect the expression of the other gene, and the recombinants only containing ecoRIIR gene appeared to be lethal to dcm+ host.

CONCLUSION

ecoRIIM gene linking closely to ecoRIIR gene is very important for the existence of the R-M system in process of evolution, but the key to control EcoRII R-M order may not exist in transcriptional level .

Electromagnetic analysis of axially symmetric diffractive optical elements illuminated by oblique incident plane waves

We present an analysis of axially symmetric diffractive optical elements illuminated by off-axis or oblique incident plane waves. The analysis is performed with a finite-difference time-domain method that has been formulated to exploit axial symmetry yet accommodate off-axis illumination. This approach is compared with a full three-dimensional formulation and is found to be more efficient in both memory requirements and computational time. Validation and applications of this method are presented.

[A study on the change of caries activity of children with fixed orthodontic treatment]

OBJECTIVE

To investigate the change of caries activity in children with fixed appliance.

METHODS

30 children of permanent dentition were treated with edgewise appliance. CAT was used to test the degree of caries activity before the orthodontic treatment, at the first week, at the first month, at the third month and at the sixth month of appliance bonding respectively.

RESULTS

Compared with pre-treatment, there was a significant difference of CAT at the first, third and sixth month of treatment; compared with the first week of treatment, there was also a significant difference of CAT at the third and sixth month of treatment.

CONCLUSIONS

The CAT degree increases in children with fixed orthodontic appliance and these children are more sensitive to dental caries.

[Study on Gong Dingguo]

It is proved through textual researches that Gong Dingguo, the author of Neifu Michuan Jingyan Nuke, was the son of gong Tingxian, a famous physician of the late Ming Dynasty.

Modification of epidermal growth factor-like repeats with O-fucose. Molecular cloning and expression of a novel GDP-fucose protein O-fucosyltransferase

The O-fucose modification is found on epidermal growth factor-like repeats of a number of cell surface and secreted proteins. O-Fucose glycans play important roles in ligand-induced receptor signaling. For example, elongation of O-fucose on Notch by the beta1,3-N-acetylglucosaminyltransferase Fringe modulates the ability of Notch to respond to its ligands. The enzyme that adds O-fucose to epidermal growth factor-like repeats, GDP-fucose protein O-fucosyltransferase (O-FucT-1), was purified previously from Chinese hamster ovary (CHO) cells. Here we report the isolation of a cDNA that encodes human O-FucT-1. A probe deduced from N-terminal sequence analysis of purified CHO O-FucT-1 was used to screen a human heart cDNA library and expressed sequence tag and genomic data bases. The cDNA contains an open reading frame encoding a protein of 388 amino acids with a predicted N-terminal transmembrane sequence typical of a type II membrane orientation. Likewise, the mouse homolog obtained from an expressed sequence tag and 5'-rapid amplification of cDNA ends of a mouse liver cDNA library encodes a type II transmembrane protein of 393 amino acids with 90.4% identity to human O-FucT-1. Homologs were also found in Drosophila and Caenorhabditis elegans with 41.2 and 29.4% identity to human O-FucT-1, respectively. The human gene (POFUT1) is on chromosome 20 between PLAGL2 and KIF3B, near the centromere at 20p11. The mouse gene (Pofut1) maps near Plagl2 on a homologous region of mouse chromosome 2. POFUT1 gene transcripts were expressed in all tissues examined, consistent with the widespread localization of the modification. Expression of a soluble form of human O-FucT-1 in insect cells yielded a protein of the predicted molecular weight with O-FucT-1 kinetic and enzymatic properties similar to those of O-FucT-1 purified from CHO cells. The identification of the gene encoding protein O-fucosyltransferase I now makes possible mutational strategies to examine the functions of the unusual O-fucose post-translational modification.

Suppression of tumor necrosis factor-mediated apoptosis by nuclear factor kappaB-independent bone morphogenetic protein/Smad signaling

The activation of nuclear factor kappaB (NF-kappa B) plays a pivotal role in the regulation of tumor necrosis factor (TNF)-mediated apoptosis. However, little is known about the regulation of TNF-mediated apoptosis by other signaling pathways or growth factors. Here, unexpectedly, we found that bone morphogenetic protein (BMP)-2 and BMP-4 inhibited TNF-mediated apoptosis by inhibition of caspase-8 activation in C2C12 cells, a pluripotent mesenchymal cell line that has the potential to differentiate into osteoblasts depending on BMP stimulation. Utilizing both a trans-dominant IkappaBalpha inhibitor of NF-kappaB expressed in C2C12 cells and IkappaB kinase beta-deficient embryonic mouse fibroblast, we show that BMP-mediated survival was independent of NF-kappaB activation. Rather, the antiapoptotic activity of BMPs functioned through the Smad signaling pathway. Thus, these findings provide the first report of a BMP/Smad signaling pathway that can inhibit TNF-mediated apoptosis, independent of the prosurvival activity of NF-kappaB. Our results suggest that BMPs not only stimulate osteoblast differentiation but can also promote cell survival during the induction of bone formation, offering new insight into the biological functions of BMPs.

[Screening of aberrant genes of immunocytes in severely scalded rats by inhibition of subtractive hybridization]

OBJECTIVE

To explore the relationship between the postburn changes of gene expression of immunocytes and postburn immunological functional disturbance in severely scalded rats.

METHODS

Immunocytes of female F344 rats with severe scalding were harvested and the mRNA was extracted for the inhibition of the expression of aberrant gene selected by subtractive hybridization in contrast to that before scalding. The aberrant genes were cloned and sequenced and compared to those in Genebank for homology.

RESULTS

The harvested immunocytes were identified by LM to be monocytes and lymphocytes. Multiple strips located at 200 approximately 400 bp were obtained by inhibiting subtractive hybridization and were cloned into PGEM-T easy plasmid vector. Thus the genebank of aberrant expression was constructed. Twenty clones were sequenced randomly and partial obtained known genes were in accord with postburn systemic changes. Several novel genes were accepted and registered by Genebank.

CONCLUSION

There exhibited change in the gene expression of peripheral immunocytes at early postburn stage in rats inflicted by severe burn.

Identification of alkylidene hydrazides as glucagon receptor antagonists

High throughput screening of our small molecule combinatorial library identified a class of benzoylnaphthalenehydrazones with modest affinity for the human glucagon receptor. Optimization of this initial hit through a series of targeted libraries and traditional medicinal chemistry led to ligands with nanomolar affinities. Pharmacological evaluation demonstrated that these ligands were competitive glucagon receptor antagonists. Intravenous administration of a representative benzoylnaphthalenehydrazone into rats attenuated glucagon-stimulated glucose levels.

Expression of inflammatory cytokines and beta-defensin 1 mRNAs in porcine epithelial rests of Malassez in vitro

In the present study, we investigated the mRNA expression of inflammatory cytokines, including interleukin (IL)-1 alpha, IL-6, IL-8, and granulocyte macrophage colony-stimulating factor (GM-CSF), and beta defensin 1 (BD-1), an antimicrobial peptide, in the epithelial rests of Malassez in vitro. A reverse transcription-polymerase chain reaction (RT-PCR) assay was performed in order to observe the expression of these mRNAs. The effect of lipopolysaccharide (LPS) on the mRNA expression was also studied by quantitative RT-PCR assay, with a LightCycler, using the double-stranded DNA dye SYBR Green I. The mRNAs of the four kinds of inflammatory cytokines and BD-1 were detected in the epithelial cells under normal culture conditions. Immunocytochemical staining showed the expression of CD14, a receptor for LPS, on the epithelial cells. The mRNA expressions of IL-1 alpha, IL-6, IL-8, and GM-CSF were upregulated by stimulation with LPS, in a dose- and time-dependent manner. Epithelial cells incubated with 1000 ng/ml of LPS for 6 h showed the most significant upregulation of the cytokine mRNAs. On the other hand, no obvious alteration of BD-1 expression by LPS stimulation was observed. The results indicated that the epithelial rests of Malassez may actively participate in the inflammatory response to bacterial infection, and that they play an important role in the defense mechanism of the radicular cyst.

[Screening and characterization of human phage antibody to hepatitis virus C NS5A antigen]

OBJECTIVE

To screen and characterize human phage antibody against hepatitis C virus (HCV)NS5A antigen.

METHODS

The recombinant phages were panned by recombinant HCV NS5A antigen which was coated in a microtiter plate; after five rounds of biopanning, 35 clones were obtained and demonstrated specific to NS5A antigen. The specific binding capacity of the ScFv antibody to HCV NS5A antigen was determined by ELISA.

RESULTS

HCV NS5A phage antibody had a specific combination capacity with hepatitis C virus NS5A antigen. The DNA sequence data showed that the ScFv gene was composed of 789 bp and codes for a peptide of 262 amino acid residues.

CONCLUSIONS

Human single chain antibody to hepatitis C virus NS5A antigen has been identified by means of the phage display technology.

[Screening and characterization of human phage antibody to hepatitis C core antigen]

OBJECTIVE

To screen and characterize human phage antibody (ScFv) against hepatitis C core antigen.

METHODS

The recombinant phages were panned by core antigen that was coated in a microtiter plate. After three rounds of biopanning, 48 clones were determined specific to core antigen. The specificity of each ScFv colone was determined by ELISA. The coding gene for HCV protein ScFv has been sequenced.

RESULTS

Phage antibody for HCV core protein had a specific combination character with core antigen of hepatitis C virus. The DNA sequence data showed that the ScFv gene included 774 bp.

CONCLUSIONS

Human single chain antibody to hepatitis C core antigen has been identified by means of the phage display technology.

[Characteristics of N2O emissions from vegetal soils on Fildes peninsula, Antarctica]

The N2O fluxes from the vegetal soils were first measured on the Fildes peninsula, Antarctica, and the total N2O emission was also estimated in the summer 2 months. The daily variations of N2O fluxes appeared single-peak trend under the sunshine or rainy weather conditions but they were irregular under the snow weather conditions and inconsistent with the atmospheric temperatures. The seasonal variations of the N2O fluxes were affected by the temperature and rainfall. The conditions during the transitions between dry and wet seasons improved the N2O emission. The total N2O emissions from moss and lichen soils were 3.7152 kg and 2.5344 kg, respectively. It follows that the vegetal soils are the sources for the atmospheric N2O on the Fildes peninsula, Antarctica.

Three-dimensional finite element analyses of four designs of a high-strength silicon nitride implant

The effects of implant shape and size on the stress distribution around high-strength silicon nitride implants under vertical and oblique forces were determined using a three-dimensional finite element analysis. Finite element models were designed using as a basis the serial sections of the mandible. Using Auto-CAD software, the model simulated the placement of implants in the molar region of the left mandible. Results of the analyses demonstrated that mainly the implant root shape and the directions of bite forces influence the stress distributions in the supporting bone around each implant. Implant size is a lesser factor. The serrated implants presented a larger surface area to the bone than either the cylindrical or tapered implants, which resulted in lower compressive stress around the serrated implants. With increasing implant diameter and length, compressive stress decreased. The mean compressive stress distribution on the serrated implants was more flat (platykurtic) than on either the cylindrical or tapered implants. Results of studies on two load directions (vertical and oblique) showed that, in either case, the compressive stress in the cortical bone around the neck of the implant was higher than in the cancellous bone along the length of the implant. The most extreme principal compressive stress was found with oblique force. This study provides the first information on the relationship between shape of the silicon nitride implant and stress on the supporting bone.

[Cloning and sequence analysis of truncated S gene from circulation of patients with chronic hepatitis B virus infection]

OBJECTIVE

To find different mutated status of HBV DNA in circulation from chronic HBV patients.

METHODS

Specially designed primers and polymerase chain reaction method were applied to amplify the whole S gene of HBV from the serum of 2 patients. After being sequenced, 4 clones were compared with HBV adr subtype (China strain) to identify the mutant sites.

RESULTS

Sequencing results implied that there was a truncated large/middle S gene in the serum of the patients. Besides that, HBsAg and HBV DNA polymerase defective clones were also detected.

CONCLUSIONS

Truncated middle S gene is found in the circulation of patients with chronical HBV infection, suggestive of a poor prognosis.

Subunit-specific rules governing AMPA receptor trafficking to synapses in hippocampal pyramidal neurons

AMPA-type glutamate receptors (AMPA-Rs) mediate a majority of excitatory synaptic transmission in the brain. In hippocampus, most AMPA-Rs are hetero-oligomers composed of GluR1/GluR2 or GluR2/GluR3 subunits. Here we show that these AMPA-R forms display different synaptic delivery mechanisms. GluR1/GluR2 receptors are added to synapses during plasticity; this requires interactions between GluR1 and group I PDZ domain proteins. In contrast, GluR2/GluR3 receptors replace existing synaptic receptors continuously; this occurs only at synapses that already have AMPA-Rs and requires interactions by GluR2 with NSF and group II PDZ domain proteins. The combination of regulated addition and continuous replacement of synaptic receptors can stabilize long-term changes in synaptic efficacy and may serve as a general model for how surface receptor number is established and maintained.

Multichannel wavelength division multiplexing with photonic crystals

A multichannel wavelength-division-multiplexing system consisting of a two-dimensional photonic crystal is proposed. The system consists of two parts, a waveguiding element, realized by defects in a photonic crystal, and frequency-selective elements, realized by photonic crystal microcavities. Simulations, performed with a two-dimensional finite-difference time-domain technique with a perfectly matched layer absorbing boundary condition, showed the ability to filter an incident pulse into six spectral channels with a FWHM of 2 nm.

Regulation of endothelial cell barrier function by calcium/calmodulin-dependent protein kinase II

Thrombin-induced endothelial cell barrier dysfunction is tightly linked to Ca(2+)-dependent cytoskeletal protein reorganization. In this study, we found that thrombin increased Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II) activities in a Ca(2+)- and time-dependent manner in bovine pulmonary endothelium with maximal activity at 5 min. Pretreatment with KN-93, a specific CaM kinase II inhibitor, attenuated both thrombin-induced increases in monolayer permeability to albumin and decreases in transendothelial electrical resistance (TER). We next explored potential thrombin-induced CaM kinase II cytoskeletal targets and found that thrombin causes translocation and significant phosphorylation of nonmuscle filamin (ABP-280), which was attenuated by KN-93, whereas thrombin-induced myosin light chain phosphorylation was unaffected. Furthermore, a cell-permeable N-myristoylated synthetic filamin peptide (containing the COOH-terminal CaM kinase II phosphorylation site) attenuated both thrombin-induced filamin phosphorylation and decreases in TER. Together, these studies indicate that CaM kinase II activation and filamin phosphorylation may participate in thrombin-induced cytoskeletal reorganization and endothelial barrier dysfunction.

A novel small molecule that directly sensitizes the insulin receptor in vitro and in vivo

Insulin resistance, an important feature of type 2 diabetes, is manifested as attenuated insulin receptor (IR) signaling in response to insulin binding. A drug that promotes the initiation of IR signaling by enhancing IR autophosphorylation should, therefore, be useful for treating type 2 diabetes. This report describes the effect of a small molecule IR sensitizer, TLK16998, on IR signaling. This compound activated the tyrosine kinase domain of the IR beta-subunit at concentrations of 1 micromol/l or less but had no effect on insulin binding to the IR alpha-subunit even at much higher concentrations. TLK16998 alone had no effect on IR signaling in mouse 3T3-L1 adipocytes but, at concentrations as low as 3.2 micromol/l, enhanced the effects of insulin on the phosphorylation of the IR beta-subunit and IR substrate 1, and on the amount of phosphatidylinositol 3-kinase that coimmunoprecipitated with IRS-1. Phosphopeptide mapping revealed that the effect of TLK16998 on the IR was associated with increased tyrosine phosphorylation of the activation loop of the beta-subunit tyrosine kinase domain. TLK16998 also increased the potency of insulin in stimulating 2-deoxy-D-glucose uptake in 3T3-L1 adipocytes, with a detectable effect at 8 micromol/l and a 10-fold increase at 40 micromol/l. In contrast, only small effects were observed on IGF-1-stimulated 2-deoxy-D-glucose uptake. In diabetic mice, TLK16998, at a dose of 10 mg/kg, lowered blood glucose levels for up to 6 h. These results suggest, therefore, that small nonpeptide molecules that directly sensitize the IR may be useful for treating type 2 diabetes.

[Cloning and sequence analysis of a pseudogene of liver regeneration augmenter in rats]

OBJECTIVE

To investigate the status of the augmenter of liver regeneration (ALR) in rat's genome.

METHODS

Polymerase chain reaction (PCR) was used to amplify the genomic DNA of rat, with a set of specific primers designed according to the cDNA sequence of ALR. The products were ligated into pGEM Teasy vector. Two positive clones were sequenced separately.

RESULTS

Two products were amplified from the rat's genome by PCR. After sequencing, one pseudogene was identified. The homology of the amino acid sequence between the ALR and its pseudogene was 88.8%.

CONCLUSIONS

ALR pseudogene is found in rat's genome, implying that there is an ALR multigene family. This finding lays a foundation for further study of ALR molecular evolution mode.

[Biodegradation behavior of ethylenediaminetetraethylene acid]

Aerobic and anaerobic degradability of ethylenediaminetetraethylene acid(EDTA) were measured on Warburg respirometer and anaerobic batch reactors. Biodegradation of EDTA as a single substance was poor, but biodegradation of EDTA with co-substrate could be improved. The wastewater containing EDTA can be treated by activated sludge process. The EDTA removal efficiency was 80% under the circumstance HRT 16 h and EDTA removal efficiency reached to 92.5%-95.1% when HRT was 20 h. The main factor affecting the biodegradability of EDTA is sludge remained time.

Paediatric hearing screening in the community: a comparison of outcomes from transient evoked and distortion product otoacoustic emission measures

The present study aimed to compare TEOAE screening outcomes based on different pass/fail criteria and the outcomes from TEOAE and DPOAE measures in children. For the purpose of the study, the subjects were divided into two age groups: group 1 (n = 36; mean age 2.7 months, SD 1.2), and group 2 (n = 29; mean age 37.5 months, SD 16.3). Results indicated that the agreement of screening outcomes between pass/fail criteria for the TEOAE measure and between TEOAE and DPOAE measures was significantly lower for the younger group than for the older group. The greater variability in the younger age group could be partly attributed to the higher physiological noise produced by young infants. Irrespective of the pass/fail criteria used, the findings of the present study suggest that the OAE outcomes for children with weak OAEs or OAEs obscured by excessive noise were most variable.

[Study on the energy transfer fluorescence quenching among combination of acridine yellow-PAR determination of trace iron]

An energy transfers technique between 4-(2-Pyridylazo) resorcinol(PAR) and acridine yellow is studied, and optimum experimental conditions of energy transfer is done as well. It is found that in the aqueous solution of sodium lauryl sulfate, NH3.H2O-NH4Cl buffer solution at pH = 9.2, the energy transfers from acridine yellow to iron(II)-PAR complexes. So a new method of fluorometric energy transfers determination of trace iron(II) by acridine yellow--PAR was described. The range of determination of iron is 0-10 micrograms.L-1. The detection limit for iron is 0.06 microgram.L-1. The method has been applied to the determination of iron in water sample and hair with satisfactory results.

Performance of Multilevel Diffractive Lenses as a Function of f-Number

We study the focusing efficiency of multilevel diffractive lenses as a function of f-number. Both scalar and rigorous analyses are performed on two- and three-dimensional lenses. We show that shadowing in lenses with small f-numbers is a critical factor that limits their performance. We show further that scalar analysis does not accurately predict the effects of shadowing for lenses with long f-numbers and large numbers of phase levels.

Study on Fas/Fas-L expression in liver tissue and hepatocyte apoptosis in patients with hepatitis gravis

To explore the expression of Fas/Fas-L in liver tissue of hepatitis gravis patients and its implication in hepatocyte apoptosis, Fas/Fas-L expression and cell apoptosis was detected by the means of inmmunohistochemistry and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL). It was found that in the 20 patients with clinical hepatitis gravis, Fas in hepatocytes showed strong expression and Fas-L also showed intensive expression in infiltrating lymphocytes and scattering hepatocytes. The apoptosis existed in all the samples, scattering in the areas of inflammatory, necrotic area and hepatic lobule. It was suggested that the overexpression of Fas/Fas-L could cause the death of hepatocytes and thus the occurrence of hepatitis gravis. The apoptosis caused by Fas might be one of the important pathogeneses of hepatitis gravis. Among the detected samples, apoptosis and necrosis coexisted, indicating that both two types of cellular death were closely associated with the pathogenesis of hepatitis gravis.

[Coefficients between TEOAEs and DPOAEs in infants]

OBJECTIVE

To investigate the coefficients of TEOAEs and DPOAEs based on various pass/fail criteria.

METHOD

Thirty-six Australia infants were tested (age range: 1-6 months) using both TEOAE and DPOAE. Cohen's Kappa (K) were used to analyze different criteria.

RESULT

There is a significant low agreement in the screening outcomes between TEOAEs and DPOAEs, and different criteria for TEOAEs.

CONCLUSION

The findings from the study of coefficients among commonly used screening pass/fail criteria suggested that there is no simple relationship among them. The possible reasons for weak agreement were discussed.

Postnatal human dental pulp stem cells (DPSCs) in vitro and in vivo

Dentinal repair in the postnatal organism occurs through the activity of specialized cells, odontoblasts, that are thought to be maintained by an as yet undefined precursor population associated with pulp tissue. In this study, we isolated a clonogenic, rapidly proliferative population of cells from adult human dental pulp. These DPSCs were then compared with human bone marrow stromal cells (BMSCs), known precursors of osteoblasts. Although they share a similar immunophenotype in vitro, functional studies showed that DPSCs produced only sporadic, but densely calcified nodules, and did not form adipocytes, whereas BMSCs routinely calcified throughout the adherent cell layer with clusters of lipid-laden adipocytes. When DPSCs were transplanted into immunocompromised mice, they generated a dentin-like structure lined with human odontoblast-like cells that surrounded a pulp-like interstitial tissue. In contrast, BMSCs formed lamellar bone containing osteocytes and surface-lining osteoblasts, surrounding a fibrous vascular tissue with active hematopoiesis and adipocytes. This study isolates postnatal human DPSCs that have the ability to form a dentin/pulp-like complex.

[Treatment of humeral shaft nonunion with interlocking nail and percutaneous injection of bone marrow]

OBJECTIVE

To investigate the effect of treatment of humeral shaft nonunion with interlocking nail and percutaneous injection of bone marrow after operation.

METHODS

Twenty-five adult patients with humeral shaft nonunion, initially treated with plates, intramedullary nails, or external fixators changed to use RussellTaylor reamed antegrade intramedullary nails with autologous bone grafting and percutaneously bone marrow injection into the fracture sites ten days after the operation to promote union.

RESULTS

All patients achieved a solid union with good function. The union period was a median of 4.5 months.

CONCLUSION

We believe that the procedure may provide firm internal fixation and improve activity of osteoblasts in fracture sites for accelerating fracture healing.

Involvement of c-Src in diperoxovanadate-induced endothelial cell barrier dysfunction

Reactive oxygen species (ROS) generated by activated leukocytes play an important role in the disruption of endothelial cell (EC) integrity, leading to barrier dysfunction and pulmonary edema. Although ROS modulate cell signaling, information remains limited regarding the mechanism(s) of ROS-induced EC barrier dysfunction. We utilized diperoxovanadate (DPV) as a model agent to explore the role of tyrosine phosphorylation in the regulation of EC barrier function. DPV disrupted EC barrier function in a dose-dependent manner. Tyrosine kinase inhibitors, genistein, and PP-2, a specific inhibitor of Src, reduced the DPV-mediated barrier dysfunction. Consistent with these results, DPV-induced Src activation was attenuated by PP-2. Furthermore, DPV increased the association of Src with cortactin and myosin light chain kinase, indicating their potential role as cytoskeletal targets for Src. Transient overexpression of either wild-type Src or a constitutively active Src mutant potentiated the DPV-mediated decline in barrier dysfunction, whereas a dominant negative Src mutant attenuated the response. These studies provide the first direct evidence for Src involvement in DPV-induced EC barrier dysfunction.

[Distribution of Prevotella intermedia in the periodontal plaques of children and their parents]

OBJECTIVE

To investigate the distribution of Prevotella intermedia (Pi) among family members by culturing technique and biochemical identification.

METHODS

Of all 60 families, 181 subjects were included in the study. Supragingival and subgingival plaques were collected and cultured, 279 strains of black-pigmented gram-negative anaerobes were obtained. Biochemical identifications were performed.

RESULTS

Pi could be identified from parents and children with healthy periodontal status. The prevalence of Pi in children was 70.49%, which was significantly higher than that in adults (43.33%).

CONCLUSION

The result indicates that Pi might be an opportunistic periodontal pathogen that could be colonized in periodontal plaques easily and early. To study the exact role of Pi in the pathogenesis of periodontitis, it is necessary to do longitudinal following study of the subjects.

Efficient combinatorial filtering for desired molecular properties of reaction products

Two combinatorial filtering methods for efficiently selecting reaction products with desired properties are presented. The first, "direct reactants" method is applicable only to those molecular properties that are strictly additive or approximately additive, with relatively small interference between neighboring fragments. This method uses only the molecular properties of reactants. The second, "basis products" method can be used to filter not only the strictly additive properties but also the approximately additive molecular properties where a certain degree of mutual influence occurs between neighboring fragments. This method requires the molecular properties of the "basis products," which are the products formed by combining all the reactants for a given reaction component with the simplest set of complementary reactant partners. There is a one-to-one correspondence between the reactants and the "basis products." The latter is a product representation of the former. High efficiency of both methods is enhanced further by a tree-sorting and hierarchical selection algorithm, which is performed on the reaction components in a limited space determined systematically from the filtering criteria. The methods are illustrated with product logPs, van der Waals volumes, solvent accessible surface areas, and other product properties. Good results are obtained when filtering for a number of important molecular properties in a virtual library of 1.5 billion.

Electromagnetic optimization of multilevel diffractive elements by use of the wavelet transform

We present an optimization algorithm for the design of multilevel diffractive optical elements in the electromagnetic domain. The method uses the wavelet transform to parameterize the diffractive optical elements according to a set of coefficients that corresponds to a multiresolution basis. Both local and global optimizations can be performed within a single algorithm. A design example consisting of the optimization of a two-dimensional millimeter-wave diffractive lens over a 10% bandwidth is presented.

A combinatorial synthesis of tyrphostins via the "directed sorting" method

Using solid-phase organic synthesis, we have prepared a 432-member (18 x 8 x 3) sample library based on the AG 490 "tyrphostin" template. By utilizing 432 reactors each equipped with a unique radiofrequency memory ID tag, the 432 products could be obtained as discrete entities (i.e., not as mixtures) via 18 + 8 + 3, or 29 reactions. Reading each ID tag after each reaction step permitted the "directed sorting" of reactors into appropriate reaction vessels containing multiple reactors. After synthesis, all products were cleaved from the solid-phase support and lyophilized to afford powders. Characterization of 5% of the library members by NMR and mass spectrometry provided verification of structure. In addition, TLC analysis of every library member provided evidence that most (or all) are composed of a single major organic compound. Some 88% of these samples were obtained in amounts of between 5 and 19 mg. Using this reaction sequence and the "directed sorting" approach, the synthesis of much larger AG 490-based libraries can be envisioned.

Three-dimensional analysis of subwavelength diffractive optical elements with the finite-difference time-domain method

We present a three-dimensional (3D) analysis of subwavelength diffractive optical elements (DOE's), using the finite-difference time-domain (FDTD) method. To this end we develop and apply efficient 3D FDTD methods that exploit DOE properties, such as symmetry. An axisymmetric method is validated experimentally and is used to validate the more general 3D method. Analyses of subwavelength gratings and lenses, both with and without rotational symmetry, are presented in addition to a 2 x 2 subwavelength focusing array generator.

[Study on blood coagulant/fibrinolytic activity at plasma and monocytic levels in coronary heart disease patients with Blood-Stasis Syndrome of traditional Chinese medicine]

OBJECTIVE

To explore and compare the changes of coagulant/fibrinolytic activity in coronary heart disease (CHD) patients with Blood Stasis Syndrome of TCM and evaluate the roles of these changes.

METHODS

Eighty patients of CHD were divided into two groups by Syndrome Differentiation of TCM, the Blood-Stasis (BS) group (30 cases) and the non-Blood-Stasis (NBS) group (50 cases, including 27 cases of Phlegm-Dampness Syndrome and 23 cases of Qi-Stagnation Syndrome); and 20 healthy persons were enrolled as normal control group. Tissue type plasminogen activator (t-PA) and its inhibitor (PAI-1) in plasma and in human peripheral blood monocyte cell (PBMC), as well as the procoagulant activity (PCA) in PBMC were measured by chromogenic substrate method.

RESULTS

The plasma PAI-1 activity and PCA of PBMC in the BS group were significantly higher than those in the NBS group and the normal control group (P < 0.01). PAI-1 activity of PBMC in the two groups of CHD patients was higher than those in the normal control group significantly (P < 0.01), but no significant difference was found between the BS group and the NBS group (P > 0.05). The difference of plasma t-PA activity between the two groups of CHD was insignificant. The PBMC t-PA activity in the BS group was lower than that in the NBS and normal control groups (P < 0.01).

CONCLUSION

In the CHD patients with BS, the PBMC PCA was increased and the fibrinolytic activity at both plasma and monocyte levels lowered significantly, these changes in coagulant/fibrinolytic activity may be the important pathologic factors in forming BS which suggests that CHD patients with BS were in the prothrombotic state.

[Expression and deletion analysis of EcoR II endonuclease and methylase gene]

OBJECTIVE

To clone complete EcoR II restriction endonuclease gene (ecoR II R) and methyl-transferase (ecoR II M) gene into one vector and to analyzing the expression of the whole system.

METHODS

Unidirective deletion subclones constructed with Exo III, ecoR II R/M genes were preliminarily located in the cloned fragments according to the enzyme activities of each subclone, exact deletion sites were determined by sequencing, and transcriptional start sites were mapped by S1 mapping.

RESULTS

The DNA fragment which was cloned into pBluescript SK+ contained the complete ecoR II R gene and ecoR II M gene, there are two transcriptional start sites in ecoR II R gene, 132 bp to 458 bp from 3' and of ecoR II R gene are indispensable to enzyme activities and deletion of 202 bp from 3' end of ecoR II M gene made it lose the capability to resist specific cut of EcoR II R enzyme, deletion of coding region and flanking sequence of one gene did not affect the expression of the other gene, the recombinant only containing ecoR II R gene appeared to be lethal to dcm + host.

CONCLUSIONS

ecoR II M gene closely linking to ecoR II R gene was very important for the existence of the R-M system in process of evolution, but the key to control EcoR II R enzyme acted later than EcoR II M enzyme did not exist in transcriptional level.

Electromagnetic analysis of axially symmetric diffractive lenses with the method of moments

We present the electromagnetic analysis of axially symmetric diffractive lenses. Analysis is performed by numerically solving the electric and magnetic field integral equations using the method of moments, and it exploits axial symmetry to reduce computational cost. Formulations for the analysis of loss less dielectric and perfectly conducting lenses are presented. The analysis of binary and eight-level lenses are performed to illustrate the utility of the technique.

alpha(1,3)fucosyltransferases expressed by the gain-of-function Chinese hamster ovary glycosylation mutants LEC12, LEC29, and LEC30

Gain-of-function glycosylation mutants provide access to glycosylation pathways, glycosylation genes, and mechanisms that regulate expression of a glycotype. Previous studies have shown that the gain-of-function Chinese hamster ovary (CHO) mutants LEC12, LEC29, and LEC30 express an N-ethylmaleimide-resistant alpha(1, 3)fucosyltransferase (alpha(1,3)Fuc-T) activity that is not detected in CHO cells and that generates the Lewis(X) but not the sialyl-Lewis(X) determinant. The three mutants differ, however, in lectin resistance properties, expression of fucosylated antigens, and in vitro alpha(1,3)Fuc-T activities. In this paper we show that each mutant expresses Fuc-TIX, but only LEC30 cells express Fuc-TIV. Using genomic PCR and reverse-transcriptase (RT)-PCR strategies, we isolated coding portions of the CHO Fut4 and Fut9 genes. Each gene is present in a single copy in the CHO and mutant genomes. The Fut4 gene is expressed only in LEC30 cells, while all three mutants express the Fut9 gene. Interestingly, the fucosylation phenotypes of LEC12 and LEC29 cells do not correlate with the relative abundance of their Fut9 gene transcripts (LEC29 >> LEC12). Compared to LEC29 cells, LEC12 cells have an approximately 40-fold higher in vitro alpha(1,3)Fuc-T activity and bind the VIM-2 monoclonal antibody, whereas LEC29 cells do not bind VIM-2. Mixing experiments did not detect Fuc-TIX inhibitory activity in LEC29 cell extracts, and CHO cells expressing a transfected Fut9 gene behaved like LEC12 cells. Therefore, it seems that LEC29 cells may not translate their more abundant Fut9 gene transcripts efficiently or may not synthesize appropriate acceptors for internal alpha(1,3)fucosylation. Alternatively, LEC12 cells may possess, in addition to Fuc-TIX, a novel alpha(1,3)Fuc-T activity.

The effect of zhu yu hua tan tang on intracranial pressure in case of acute cerebral hemorrhage

The therapeutic effect of Zhu Yu Hua Tan Tang ([symbol: see text] Decoction for removing blood stasis and resolving phlegm) plus general and modern treatment on acute cerebral hemorrhage in 44 cases, and the pressure-lowering effect of Zhu Yu Hua Tan Tang and mannitol in 20 cases of acute cerebral hemorrhage in the basilar region, and in rabbits with experimental encephaledema induced by injection of olive oil into the common carotid artery were observed in this study. The results showed that Zhu Yu Hua Tan Tang plus general treatment can better improved the conscious state of the patients than western medicine, and it can make the intracranial pressure drop clinically by 40.44%. The intracranial pressure-lowering effect of Zhu Yu Hua Tan Tang, though slow, is smooth and long-lasting without any rebound phenomenon, as compared to those of mannitol. Similar results were found in animal experiments, but the intracranial pressure-lowering amplitude of Zhu Yu Hua Tan Tang was stronger than that of mannitol. The difference between the clinical and experimental results needs to be further studied.

[Studies on chemical constituents of fat oil of Polygala tenuifolia]

OBJECTIVE

To study the chemical constituents of fat oil from root of Polygala tenuifolia Willd.

METHOD

The components were separated and identified by gas chromatograpy-mass spectrometry and elucidated on the standard mass spectral data and the percentages were determined by gas chromatographic area normalization method.

RESULT

Eighteen constituents were separated and sixteen of them were identified.

CONCLUSION

The major components of the fat oil were established first time as oleic acid, linoleic acid, palmitic acid, eicosenoic acid and stearic acid, which make up 87.0%, 7.31%, 3.27%, 1.07%, 0.91% of fat oil respectively.

[AM signals' digital demodulation and its application in physiological signals' remote transmission]

Taking advantage of the characteristics of digital systems, a new digital method is given in this article to overcome the difficulties in demodulating AM signals using digital methods. Physiological signals can't be transmitted through telephone networks because they are full of ultra-low frequency components. However, if they are modulated (such as AM), they can be transmitted to the receiving end through telephone networks. Then phaselocked loops can be employed to trace the frequency of the signals' carriers so that we can demodulate and transmit them in the end.

[Seeking behavior of patients with mental disorders and interfering factors]

OBJECTIVE

To approach different help-seeking behavior and its effects on patients with mental illness.

METHODS

We investigated the patients first seeking help in psychiatry department, by applying the scale of help-seeking behavior of mental illness.

RESULTS

There were significant differences among different mental disorders. 50% patients with mania, 66% with schizophrenia, and about 90% with depression or neurosis first went to general hospital when their illness began. About 80% patients considered their symptoms as normal, temperament, and mood problems. The course of one-third patients was one year, and most patients were treated with traditional herbs, west drugs and tests. Nearly 10% patients with depression, neurosis and schizophrenia spent more then 10 000 yuan before seeking the doctor in psychiatry.

CONCLUSION

Now then it is still a main problem for patients with mental disorders in seeking behavior. We suggest that the propaganda of the knowledge of mental health should be paid more attention, especially for the people in community and doctors in general hospital.

Noncollinear-pumped KTP optical parametric oscillator

A theoretical analysis and an experimental study are presented on the phase-matching condition of noncollinearly pumped optical parametric oscillators (OPO's) based on a noncritical phase-matching potassium titanyl phosphate (KTP) OPO. It is shown that noncollinearly pumped, double-pass, singly resonant optical parametric oscillators maintain the advantage of round-trip parametric gain in a collinear pump, since in this case the two generated signal waves are coherent, which results in high conversion efficiency and low pump threshold. With this KTP OPO we achieved 31% energy conversion efficiency from a 1064-nm pump wave to 1572-nm eye-safe output. In addition, because the incident pump beam is not perpendicular to the OPO cavity mirrors and consequently no reflected beam flows back into the pump source, we can avoid employing optical isolators.

Vector-based plane-wave spectrum method for the propagation of cylindrical electromagnetic fields

We present a vector-based plane-wave spectrum (VPWS) method for efficient propagation of cylindrical electromagnetic fields. In comparison with electromagnetic propagation integrals, the VPWS method significantly reduces time of propagation. Numerical results that illustrate the utility of this method are presented.

Chromosomal localization of the loci responsible for dystrophic cardiac calcinosis in DBA/2 mice

Dystrophic cardiac calcinosis (DCC) occurs in certain inbred strains of mice, including DBA/2 and C3H/He, and is generally found as an incidental lesion in adult animals at necropsy. Preliminary genetic studies into the cause of DCC have been performed in DBA/2 mice and suggest that DCC is inherited as an autosomal recessive trait involving three or four unlinked genes. To investigate the genetics of DCC further, we produced myocardial cell death by freeze-thaw injury to induce DCC. Experiments were conducted with three F1 hybrids made using three inbred strains of mice (DBA/2J and C3H/HeJ, DCC-susceptible strains; C57BL/6J, DCC-resistant strain) to compare the genetic factors in the development of DCC. We found that DBA/2 and C3H/He mice share the same gene pattern(s) that is responsible for DCC. We determined by backcross linkage analysis in DBA/2 and C57BL/6 mice that at least one recessive locus is responsible for DCC. A haplotype analysis of the backcross data demonstrated that the recessive locus, designated dyscalc1, is located on Chromosome 7, 20.5 cM distal to the centromere. The likely candidate genes for dyscalc1 are discussed. Further understanding of the structure and function of these mutant genes will be beneficial in explaining the molecular pathogenesis of DCC.

[Histomorphometry of silicon nitride composite endosteal implant in dogs]

OBJECTIVE

To study the dynamic changes of bone interface with silicon nitride (Si3N4) composite implants.

METHODS

4 Beagle dogs were experimental animals, Si3N4-HA and pure Si3N4 implant were experimental group, and Ti and Ti-HA were used as comparisons. They were implanted into dogs' femurs by stages. Histomorphometry was used to analyse and compare bone growth metabolism of bone interface with implant as well as evaluation of biocompatibility from quantitative and dynamic aspects.

RESULTS

Parameters expressing mineralization and speed of deposition at the Si3N4-HA bone interface were higher than comparisions' at the first month. After 6 months, pure Si3N4's bone histomorphometic parameters had no notable difference with others.

CONCLUSION

New implant material is useful to the clinic. The histomorphometry is of much value for the study of interface bone metabolism from quantitative and dynamic point of view.

[Clinical significance of changes of interleukin 6 level in pregnancy induced hypertension]

OBJECTIVE

To assess the clinical significance of changes of interleukin-6 (IL-6) level in patients with pregnancy induced hypertension (PIH).

METHODS

IL-6 level in urine and blood were measured by sandwich enzyme labeled immunosorbent assay (ELISA) in 82 patients with PIH and 30 normal pregnant women.

RESULTS

Blood IL-6 level in severe PIH patients was significantly higher than that in mild PIH patients and normal pregnant women. IL-6 level of urine in PIH patients were significantly higher than that in normal pregnant women and was associated with the severity of disease. There was a positive correlation between urinary IL-6 level and severity of renal damage in PIH.

CONCLUSION

Determination of IL-6 level is useful to understand the severity of PIH and its renal damage.

Field stitching algorithm for the analysis of electrically large diffractive optical elements

A rigorous electromagnetic algorithm is presented for the analysis of electrically large diffractive optical elements (DOE's), i.e., those that contain small features and have large apertures compared with the wavelength of illumination. The technique uses a finite-sized analysis window within which a rigorous electromagnetic technique is used to solve the local boundary-value problem. To this end the boundary-element and finite-difference time-domain methods are used. The analysis window is translated over the entire surface of the DOE and stitches together the complete solution. We validate the techniques by comparing the stitched boundary fields with those of a complete analysis, in both magnitude and phase, for a binary lens. To illustrate the utility of our method we analyzed an eight-level diffractive lens with a 10, 000-wavelength diameter sampled at 0.05 wavelength that required 8 Mbytes of memory on a desktop personal computer.

Role of tyrosine phosphorylation in thrombin-induced endothelial cell contraction and barrier function

Thrombin-induced endothelial cell (EC) barrier dysfunction is highly dependent upon phosphorylation of serine and threonine residues present on myosin light chains (MLC) catalyzed by a novel EC myosin light chain kinase (MLCK) isoform. In this study, we examined the participation of tyrosine protein phosphorylation in EC contraction, gap formation and barrier dysfunction. We first determined that thrombin significantly increases protein tyrosine kinase activity and protein tyrosine phosphorylation in bovine pulmonary artery EC. Tyrosine kinase inhibitors, genistein and 2,5 DHC, reduced EC tyrosine kinase activities, however, only genistein significantly attenuated thrombin-mediated increases in albumin clearance and reductions in transendothelial electrical resistance. Similarly, genistein but not 2,5 DHC, decreased basal and thrombin-induced Ca2+ increases and MLC phosphorylation in the absence of alterations in Type 1 or 2A serine/threonine phosphatase activities. Immunoprecipitation of the EC MLCK isoform revealed a 214 kD immunoreactive phosphotyrosine protein and genistein pretreatment significantly reduced MLCK activity in MLCK immunoprecipitates. Although thrombin induced the translocation of p60src from the cytosol to the EC cytoskeleton, a detectable increase in the level of MLCK tyrosine phosphorylation was not noted after thrombin challenge. Taken together, our data suggest that genistein-sensitive tyrosine kinase activities are involved in thrombin-mediated EC MLCK activation, MLC phosphorylation, and barrier dysfunction.

A study of the relationship between caries activity and the status of dental caries: application of the Dentocult LB method

OBJECTIVE

To clarify the relationship between caries activity and the status of caries of primary teeth and the relationship between the quantity of Lactobacillus in the oral cavity and the status of dental caries.

METHODS

The status of caries of primary teeth in 164 children ages 3 to 5 was examined. Caries incidence, mean DFT, and Caries Severity Index (CSI) were calculated. Based on the quantity of Lactobacilli in the saliva of preschool children detected with the Dentocult LB method of caries activity, four grades were classified: Grade 0 = 10(3) CFU/mL, Grade I = 10(4) CFU/mL, Grade II = 10(5) CFU/mL, and Grade III = 10(6) CFU/mL.

RESULTS

The results showed that 34.15% of the children had caries status beyond Grade I. There were significant differences of caries status, DFT, and CSI among different grades, all of which increased with grades. There was a high correlation between grades and caries incidence, DFT, and CSI in the 164 preschool children.

CONCLUSION

As a Caries Activity Test (CAT), detection of Lactobacilli may reveal the status of dental caries and provide valuable information for the prevention and treatment of dental caries.