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A study on combined manual materials-handling tasks performed on floors under three friction levels was conducted. Eight male subjects participated in the study. The maximum acceptable weight of handling, including lifting, carrying for 3m, lowering, and walking 3m back at twice per minute was determined. The subject then performed the same tasks for 10 min. Heart rate, Vo2, energy efficiency, perceived sense of slip, and rating of perceived exertion for whole body strain were measured. The results showed that the effects of friction level on the maximum acceptable weights of handling, perceived sense of slip, Vo2, and energy efficiency were statistically significant (p

Background: Both p16(INK4) and p21(Waf1) are tumor suppressors with similar biological functions in the regulation of cellular senescence. Previous reports showed that p16(INK4) could be activated by p21(Waf1) through transcriptional factor Sp1 in HeLa cells. This study was undertaken to determine the effects of p16(INK4) on the expression and functions of p21(Waf1)., Methods: Human diploid fibroblast 2BS cells were stably transfected with sense (2BS/p16(INK4)), antisense p16(INK4) (2BS/asp16(INK4)) or empty vector (2BS/neo). Then they were assayed by reverse-transcription polymerase chain reaction (RT-PCR), fluorescence activated cell sorting (FACS) and Western blot., Results: 2BS/p16(INK4) cells exhibited cell cycle arrest in both G1 and G2/M phases. Endogenous p21(Waf1) protein levels increased twofold in the 2BS/p16(INK4) cells, but not decreased in the 2BS/asp16(INK4) cells. p21(Waf1) mRNA levels were not affected in neither 2BS/p16(INK4) nor 2BS/asp16(INK4) cells., Conclusion: p16(INK4) may play an important role in the regulation of cellular senescence by modulating the p21(Waf1) protein level via the posttranscriptional mechanism.

Objective: To examine the proliferation of myofibroblast in periodental tension side of beagle dog during experimental tooth movement in orthodontics., Methods: By the fixed orthodontic appliance, the five beagles were treated with 100 g forces that moved medially the maxillary first premolar, and the treatment lasted for four weeks. Using transmission electron microscope and immunohistochemistry, the proliferation of myofibroblast and expression of alpha-smooth muscle actin (alpha-SMA) were evaluated at week 1, 2, 3, 4 or 8 respectively after the orthodontic treatment., Results: During the total of four weeks, the expression of a-SMA increased in week 1 and reached the maximum in week 2; in week 4, the expression of alpha-SMA went back to normal level. Transmission electron microscopy showed that the myofibroblast contained the dense body appearing in cytoplasm., Conclusion: The myofibroblast exists in periodontium and is concerned with the orthodontic tooth movement.

Multimedia techniques were applied in parasitological teaching and experimental practices. In order to strengthen the practical ability of the undergraduate students, reform was conducted including a prioritization of the teaching content, use of series micro-slides and video show, etc.

An efficient system of genetic transformation and plant regeneration via somatic embryogenesis was established in crownvetch (Coronilla varia L.) by infecting the segments of cotyledons and hypocotyls of 15d-old seedlings with Agrobacterium rhizogenes strain 15834. Hairy roots were produced directly from the wounded surface of the explants or via calluses on hormone-free Murashige and Skoog (MS) medium after infection by A. rhizogenes. Transformed roots grew rapidly either on solid or liquid MS medium, and exhibited typical hairy root phenotypes. The highest transformation frequency (87.4%) was achieved by preculturing cotyledons for 2d and pre-treating the A. rhizogenes with suitable concentration of acetosyringone at logarithmic phase (OD600 = 0.8). The embryogenic calluses with 100% induction frequency were induced from hairy roots on MS medium containing 0.2mg/L 2,4-D, 0.5mg/L NAA and 0.5mg/L KT. Globular-, heart-, torpedo-, and cotyledon shaped somatic embryos were produced orderly and developed into plantlets when transferred the embryogenic calluses on MS medium supplemented with 0.5mg/L KT, 0.2mg/L IBA and 300mg/L proline. The transformed plants did not show differences in morphology except abundant lateral root branches compared to the non-transformed plants. However, the contents of 3-nitropropanic acid in hairy roots and leaves of one of 5 transformed clones were 57.68% and 58.17% in roots and leaves of untransformed plants, respectively. Opine paper electrophoresis revealed the integration and expression of TR-DNA. PCR analysis confirmed that the TL-DNA including 654 bp rol B sequence was inserted into the genome of transformed hairy roots and their regenerated plants.

Objective: To explore the effect of thymopentin (TP5) on the choice of ethanol and ameliorating withdrawal symptoms (anxiety) of ethanol in mice., Methods: Mice were administered ethanol (v/v) in schedular fashion: 5% (1 week), 10% (1 week) and 15% (4 weeks), followed with the free choice between ethanol and water. Ethanol/(ethanol+water)x100% [E/(E+W)x100%] was measured as an index of ethanol selection. Light-dark box test and elevated plus maze test were chosen for the assessment of anxiety pre-drug and post-drug. After TP5 [0.2 mg/(kgxd), 0.4 mg/(kgxd)], i.p. or saline (vehicle control), i.p. for 14 days, the procedure was repeated., Result: (1) E/(E+W)x100%: the post-drug values of TP5 (0.2 mg/kg, 0.4 mg/kg) were lower significantly than the pre-drug values. (2) Light-dark box test: the post-drug values of number of entries and time spent in the light chamber of TP5 (0.2 mg/kg, 0.4 mg/kg) were more than the pre-drug values themselves and the post-drug value of saline. (3) Elevated plus maze test: the post-drug values of time spent on open arms of TP5 (0.2 mg/kg, 0.4 mg/kg) were more than the pre-drug values themselves and the post-drug value of salineìand the post-drug values of time spent on close arms of TP5 were less than the pre-drug values., Conclusion: TP5 could decrease the uptake of ethanol and ameliorate anxious behavior associated with ethanol withdrawal in mice.

Objective: To survey the prevalence of dental caries and the needs for dental treatment in Anhui province., Methods: The survey of prevalence of dental caries in group aged 12 and 15 years in Anhui province was conducted using the non-proportional, stratified, cluster sampling method., Results: DMFT in 12-year and 15-year group was 0.58 and 0.95 respectively, and permanent tooth caries prevalence rate was 30.78% and 39.78% respectively, lower than that of same age of other 11 provinces in mainland China (P < 0.01). The constituent ratio of DMFT was 90.51% (D), 2.48% (M), 7.01% (F) in 12-year group and 86.78% (D), 4.30% (M), 8.92% (F) in 15-year group., Conclusions: When we controlled dental caries in 19.98% 12-years crowd and 22.8% 15-years crowd of Anhui province, we will had controlled the occurrence of 80% caries too in group aged 12 and 15 years.

Objective: To study the factors of colorectal cancer (CRC) after radical resection to provide data predicting the prognosis of the patients., Methods: 120 cases of CRC were collected in this study. Medical clinical records and 5-year follow-up data were reviewed. Streptavidin-peroxidase immunohistochemical technique was used to detect the expression of p53, C-erbB-2, nm23-H(1) and Ras on formalin-fixed, paraffin embedded sections of CRC from the 120 patients., Results: Results showed that the rates of positive expression of p53, C-erbB-2, Ras and nm23-H(1) were 62.5% (75/120), 25.8% (31/120), 80.0% (96/120) and 60.8% (73/120) respectively in the CRC tissue. All pathological variables and biological markers were analyzed with Cox regression model (alpha = 0.05). Eight distinguished prognostic factors were identified in the univariate analysis as: macroscopic configuration, histology grade, depth of invasion of intestinal, lymph nodes metastasis, Dukes' classification, p53, Ras and nm23-H(1). The results of multivariate analysis (alpha = 0.05) indicated that the independent prognostic factors were Dukes' classification, p53 and nm23-H(1) (P = 0.000), with relative risk of 3.06, 6.02 and 0.40, respectively. A prognostic model: h(t, x) = h(0)(t)exp (-0.9269X(14) + 1.1197X(10) + 1.7948X(11)) was established. Sensitivity, specificity agreement and reliability of the model and Kappa were 79.1%, 83.0%, 80.8% and 0.62, respectively., Conclusion: Dukes' classification, p53 and nm23-H(1)seemed to be independent and important prognostic factors. This prognostic model could be used to evaluate the prognosis of patients with CRC by clinicians.

The nonlinear predator-prey reaction diffusion systems for singularly perturbed Robin Problems are considered. Under suitable conditions, the theory of differential inequalities can be used to study the asymptotic behavior of the solution for initial boundary value problems.

Objective: The first study on the epidemiology of oral health status in AnHui province was held. The purpose of this survey was to investigate the prevalence of dental diseases and the needs of dental treatment, so as to develop effective programs in providing dental care in children., Methods: Non-proportional stratified cluster sampling was used for this study., Results: The results showed that XDMFT in this group was 0.95, permanent caries prevalence rate was 39.78%, lower than that of the same age children in other 11 provinces in Mainland(P < 0.001). The proportion of DMFT was 86.78%(D), 4.30% (M), 8.92% (F), respectively. The caries number that needed dental care were 1842 teeth(0.78 teeth per person)., Conclusion: The caries prevalence rate, the XDMF and the "F" were lower than the same age children in 11 provinces in Mainland and the "M" was higher.

The inheritance of head and neck color and black hoof of Boer goats and their offspring were analyzed by observing,breeding data and statistic test in the Crossbreeding and Improving Research Center of Boer goat in Qinhuangdao city. The results indicated that the color of head and neck and black hoof of Boer goat were all controlled respectively by two linked recessive genes on one autosome. The rate of crossing-over between the genes of head and neck color and black hoof was 7.5 genetic units.

Surface Enhanced Raman Scattering (SERS) combined with Thin Layer Chromatography (TLC) has been used for studying characteristic spectrum of molecules in situ in micrograms samples. There are very few report for applying the SERS-TCL method in the study of the effective ingredients of Chinese traditional herbs. Coptis Chinensis France is an often-used clinic Chinese traditional medicine. Its main effective components include berberine and so on, which have antibiotic very wide and also have curative effect on improving the functions of heart vascular cycles. Therefore the concentrations of berberine are very important for the quality control of the medicine. In this work, the ethanol extract of Coptis Chinensis France was first separated by TLC, the SERS was then measure directly after dropping silver gel on the separated spots. The method can be used for the finger print analysis of the berberine. 3 microL of alcohol extract of Coptis Chinensis France with total alkaloids concentration of 1.0 mg.mL was placed on silicon GF254 TLC plate. The sample was separated by developing solvent of n bulanol-Acitic acid-H2O (7:2:1 V/V). The positions of berberine in the sample were confirmed by the standard alkaloid solutions. The Rf values for berberine are 0.29. The silver gel was used as surface enhanced substrate and placed on the separated berberine spots. FT-SERS was measured directly by a Nicolet FT-Raman 910 spectrometer. Berberine belong to isoquinoline alkaloids. His structure can be found in reference. The date of spectrum of berberine can be seen that the band at 1,396 cm-1 due to Ar-OCH3 deformation vibrations was greatly enhanced, indicating that the molecule was absorbed on silver gel strongly through lone-pair electron in Ar-OCH3. The ring stretching mode occurring around 1,548 cm-1 represents isoquinoline ring in the molecule. The band at 727 cm-1 due to CH (ring) deformation vibrations was also enhanced.

Objective: To investigate mechanical properties of titanium alloy samples with vacuum-sintered powder metallurgy., Methods: Titanium based metal powder mixtures were compacted into green bodies in the double action press and sintered at 1000 degrees centigrade for 15 minutes in a vacuum furnace at 0.025Pa. Then the mechanical properities of the sintered compacts were evaluated., Results: Compressive strength of sintered bodies were 111-921MPa when compacted pressure increased from 100MPa to 300MPa. Compressive strength of sintered bodies increased with compacted pressure. Three particle sizes of titanium powder, -160 mesh, -200/+300 mesh, -300 mesh, did not affect the mechanical properties of sintered bodies. The compressive strength of sintered bodies with the plating of copper and tin were higher than those without the plating. Three-point bending strength and elastic modulus of sintered bodies were respectively 102-182MPa and 12193-26630 when compacted pressure affect the mechanical properties pf sintered compacts. Titanium powder plated with copper and tin is compacted and sintered easily, the mechanical properties of sintered compacts are greatly improved.

Objective: To develop an in vitro method for the assessment of drug response in P. falciparum to pyronaridine/sulfadoxine/pyrimethamine (PND/S/P)., Methods: The PND/S/P microtest plate was designed, Rieckmann in vitro microtest(WHO standard kit) was used to test the sensitivity of P falciparum in continuous culture (FCC1/HN strain), and the data obtained were analyzed using a computer programme. Fractional inhibitory concentration (FIC) was calculated to test the possible synergy between PND and S/P., Results: The effect of the PND/S/P plates was fairly stable and the ED50 values of pyronaridine, sulfadoxine and pyrimethamine were 0.11, 215.12 and 2.9 pmol, respectively. The FIC obtained confirmed the synergism between PND and S/P., Conclusion: The in vitro method can be used to assess the sensitivity of P. falciparum to pyronaridine/sulfadoxine/pyrimethamine.

The human homolog of mouse NF-E2 was isolated from the K562 cell line and found to encode a member of the basic leucine-zipper family of DNA-binding regulatory proteins. The deduced amino acid sequence of the mouse and human proteins exhibited near identity. Comparison to the related protein, Nrf1, revealed significant homologies at isolated regions, particularly within the basic domain, suggesting that NF-E2 and Nrf1 are members of a distinct subfamily of basic leucine-zipper proteins that share similar DNA-binding properties. High levels of human NF-E2 mRNA were observed in human erythroleukemic cell lines examined. Extensive survey of human tissue samples found NF-E2 expression not limited to erythropoeitic organs. Expression in the colon and testis suggests that NF-E2 may participate in the regulation of genes other than globin.

We have devised a complementation assay in yeast to clone mammalian transcriptional activators and have used it to identify a human basic leucine-zipper transcription factor that we have designated Nrf1 for NF-E2-related factor 1. Nrf1 potentially encodes a 742-aa protein and displays marked homology to the mouse and human NF-E2 transcription factors. Nrf1 activates transcription via NF-E2 binding sites in yeast cells. The ubiquitous expression pattern of Nrf1 and the range of promoters containing the NF-E2 binding motif suggest that this gene may play a role in the regulation of heme synthesis and ferritin genes.

The antiestrogen tamoxifen, increasingly used as adjuvant treatment for breast cancer, has been found to covalently modify DNA of rodents. For instance, the liver DNA of female Sprague-Dawley rats treated with a single injection of tamoxifen contained two DNA adducts. Four additional DNA adducts were formed and adduct concentrations increased 5- 7- and 10-15-fold after three and six tamoxifen injections, respectively, from levels observed after a single dose. The accumulation of DNA adducts with repeated administrations of tamoxifen to rodents may make this drug a poor choice for the chronic preventative treatment of breast cancer.

We investigated the effects of MA-5, a human-specific monoclonal antibody to the insulin receptor alpha-subunit, on transmembrane signaling in cell lines transfected with and expressing both normal human insulin receptors and receptors mutated in their beta-subunit tyrosine kinase domains. In cell lines expressing normal human insulin receptors, MA-5 stimulated three biological functions: aminoisobutyric acid (AIB) uptake, thymidine incorporation, and S6 kinase activation. Under conditions where these biological functions were stimulated, there was no detectable stimulation of receptor tyrosine kinase. We then combined the use of this monoclonal antibody with cells expressing insulin receptors with mutations in the beta-subunit tyrosine kinase domain; two of ATP binding site mutants V1008 (Gly----Val) and M1030 (Lys----Met) and one triple-tyrosine autophosphorylation site mutant F3 (Tyr----Phe at 1158, 1162, and 1163). In cells expressing V1008 receptors, none of the three biological functions of insulin was stimulated. In cells expressing M1030 receptors, AIB uptake was stimulated to a small, but significant, extent whereas the other two functions were not. In cells expressing F3 receptors, AIB uptake and S6 kinase activation, but not thymidine incorporation, were fully stimulated. The data suggest, therefore, that (1) activation of insulin receptor tyrosine kinase may not be a prerequisite for signaling of all the actions of insulin and (2) there may be multiple signal transduction pathways to account for the biological actions of insulin.

Methods for the efficient use of limiting amounts of fatty acid probes in the synthesis of individual molecular species of plasmenylcholine have been developed. Plasmenylcholine molecular species were synthesized through acylation of homogeneous 1-O-(Z)-hexadec-1'-enyl-sn-glycero-3-phosphocholine utilizing fatty acid anhydrides generated in situ from combined pools of reactant and recycled fatty acids by repeated addition of small amounts (10 mol%) of N,N'-dicyclohexylcarbodiimide. The efficient generation of reactive anhydrides was accomplished through minimizing irreversible formation of N-acyl urea adducts by maintaining a persistent molar excess of fatty acid (with respect to carbodiimide) during the entire reaction time course. The synthesis of multiple different sn-2 labeled plasmenylcholine probes for utilization in fluorescence, ESR, or 2H NMR spectroscopy as well as isotopically labeled plasmenylcholines for metabolic studies has been achieved in good yield (40-50% of theoretical yield based on fatty acid) by these methods. Rapid and effective purification methods utilizing high-performance liquid chromatography were developed for both large- and small-scale purifications of individual reaction mixtures which collectively resulted in the isolation of homogeneous plasmenylcholine molecular species in high yield from limiting amounts of fatty acid probes.

The dynamics of binary mixtures of choline glycerophospholipids and lysophospholipids were examined by fluorescence spectroscopy to compare and contrast the effects of each subclass of lysophospholipids on plasmenylcholine and phosphatidylcholine membrane motional characteristics. The decrease in steady-state anisotropy resulting from the introduction of lysoplasmenylcholine into plasmenylcholine bilayers was 4-6-fold greater than that manifest from the introduction of lysophosphatidylcholine into phosphatidylcholine bilayers (i.e., delta r = 0.017 vs. 0.004 or 0.011 vs. 0.002 at 5 C degrees and 10 C degrees above their phase transition temperatures, respectively). Lysoplasmenylcholine was also more potent than lysophosphatidylcholine in perturbing the dynamics of membrane bilayers comprised of phosphatidylcholine as measured by alterations in the steady-state anisotropy of the diphenylhexatriene probe. Finally, lipid matrices comprised of plasmenylcholine were uniformly more susceptible to amphiphilic perturbation (mediated by lysoplasmenylcholine, lysophosphatidylcholine or long chain acylcarnitine) than matrices comprised of phosphatidylcholine. Collectively, these results demonstrate that accumulation of plasmalogen catabolites resulting from activation of plasmalogen-selective phospholipases A2 can potentiate alterations in membrane dynamics during signal transduction in plasmalogen-enriched bilayers.

Physiologically relevant molecular species of plasmenylcholine and phosphatidylcholine were synthesized and their molecular dynamics and interactions with cholesterol were compared by determination of salient proton spin-lattice relaxation times and apparent activation energies for 1H-NMR observable motion. The molecular dynamics of PA PhosCho (1-hexadecanoyl-2-eicosatetra-5',8',11',14'-enoyl-sn-glycero-3-pho sphocholine) in multiple regions of the bilayer. Furthermore, the fluidity gradient of PA PhosCho was larger than that of PA PlasCho as ascertained by 1H spin-lattice relaxation time measurements. Introduction of cholesterol into each bilayer resulted in disparate effects on the dynamics of each subclass including: (1) increased motional freedom in the polar head group of PA PlasCho without substantial alterations in the dynamics of the polar head group of PA PhosCho; and (2) increased immobilization of the membrane interior in PA PlasCho in comparison to PA PhosCho. Analysis of Arrhenius plots of T1 relaxation times demonstrated that the apparent activation energies for vinyl and bisallylic methylene proton NMR observable motion in PA PhosCho were greater than that in PA PlasCho. Thus, comparisons of spin-lattice relaxation times and apparent activation energies demonstrate that vesicles comprised of PA PlasCho and PA PhosCho possess differential molecular dynamics and distinct interactions with cholesterol. Collectively, these results underscore the significance of the conjoint presence of the vinyl ether linkage and arachidonic acid as an important determinant of membrane dynamics in specialized mammalian membranes.

The conformation of plasmenylcholine near the hydrophobic-hydrophilic interface in membrane bilayers was deduced by determination of critical internuclear distances utilizing truncated driven nuclear Overhauser enhancement. These experiments demonstrated that the beta-vinyl ether proton in plasmenylcholine was in close spatial proximity and nearly equidistant (approximately 3 A) to both the alpha- and beta-methylene protons of the sn-2 aliphatic chain. In contrast, the distances between the alpha-vinyl ether proton and the alpha- and beta-methylene protons of the sn-2 aliphatic chain were greater than or equal to 5 A. Furthermore, the distance between the N-CH3 protons in the polar head group and the methylene protons of the glycerol backbone in plasmenylcholine vesicles is larger than that present in phosphatidylcholine vesicles. Although the proximal portion of the sn-2 acyl chain in phosphatidylcholine is bent, conformational analysis utilizing these distance constraints demonstrated that the carbon atoms which comprise the proximal portion of the sn-2 aliphatic chain in plasmenylcholine are nearly coplanar, in register, and parallel to the sn-1 aliphatic chain. Taken together, these observations indicate that modest covalent alterations in the proximal portion of the sn-1 aliphatic chain in choline glycerophospholipids result in substantial changes in the molecular conformation and packing of hydrated phospholipid bilayers.

Kidney volume in 87 patients with NIDDM was measured by ultrasound scanning. The poorly controlled diabetics with HbA1 greater than 9.8% showed increased kidney volume (169.5 +/- 24.8 ml/1.73 m2) being larger than normal controls (155.6 +/- 17.3 ml/1.73 m2). The kidney volume was within normal range in diabetics (152.2 +/- 19.3 ml/1.73 m2) with good metabolic control (HbA1 less than 9.8%). There exists a positive correlation between kidney volume and HbA1 level (r = 0.5460, n = 87, P less than 0.01). After effective metabolic control of over 3 months, the increased kidney volume showed significant decrease with reduction of HbA1 level.