Inducible nitric oxide synthase inhibition of weibel-palade body release in cardiac transplant rejection

BACKGROUND

Inducible nitric oxide synthase (iNOS, or NOS2) reduces the severity of accelerated graft arteriosclerosis (AGA) in transplanted organs, although the precise mechanism is unclear.

METHODS AND RESULTS

We transplanted wild-type murine hearts into either wild-type or NOS2-null recipient mice; we then measured cardiac allograft survival and analyzed tissue sections by immunohistochemistry. We have confirmed that NOS2 increases cardiac allograft survival. We now show that there is less inflammation of cardiac allografts in wild-type hosts than in NOS2-null hosts. Furthermore, staining for von Willebrand factor reveals that the presence of NOS2 is correlated with the presence of Weibel-Palade bodies inside endothelial cells, whereas the absence of NOS2 is correlated with the release of Weibel-Palade bodies.

CONCLUSIONS

Weibel-Palade bodies contain mediators that promote thrombosis and inflammation. Therefore, nitric oxide (NO) may stabilize the vessel wall and prevent endothelial activation in part by inhibiting the release of the contents of Weibel-Palade bodies. Prevention of Weibel-Palade body release might be a mechanism by which NO protects the vessel wall from inflammatory disorders such as atherosclerosis or graft arteriosclerosis.

Three new glycosides from Sinopodophyllum emodi (Wall.) Ying

Tow new aryltetralin-type lignan glycosides: methyl epipodophyllate 7'-O-beta-D-glucopyranoyl-(1-->6)-beta-D-glucopyranoside (1), 4-demethylepipodophyllotoxin 7'-O-beta-D-glucopyranoside (2), and a new phenyl ethanol glycoside: phenyl ethanol 4-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside (3), along with three known compounds: junipetriolosides (4), 3,4-dihydroxy-phenyl ethanol (5), and 4-hydroxy-phenyl ethanol (6) were isolated and identified from the n-butanol extract of the roots and rhizomes of Sinopodophyllum emodi (Wall.) Ying. The structures of the above were established by means of spectral data and chemical methods.

Protection of photoreceptor cells in adult rats from light-induced degeneration by adaptation to bright cyclic light

Light history has been shown to affect the susceptibility of the albino rat retina to the damaging effects of constant light exposure. Retinas of animals raised in relatively bright cyclic light are protected against light-induced degeneration compared with dim-reared animals. These effects were observed in animals raised from birth in bright cyclic light and are part of an adaptive response that protects photoreceptors from stress-induced degeneration. To determine if retinas of adult animals are capable of such adaptive changes or flexibility by switching between different light environments which do not pathologically damage photoreceptor cells, albino rats were maintained in less than 250 lux cyclic light for more than 3 weeks. At 12-13 weeks of age, they were placed into 800 lux cyclic light for 1 week, after which they were exposed to constant illumination of 1500-lux for 1, 3 or 7 days. Retinal function was evaluated by electroretinography and photoreceptor cell death was quantified by measuring outer nuclear layer thickness. After 1 week in bright cyclic light, the retinas were completely protected against 1 day constant light exposure that significantly damaged retinas of animals without 800 lux cyclic light adaptation. Significant protection was also observed in 3 day constant light exposed animals; limited protection occurred after 7 days exposure. These results indicate that the retinas of adult rats adapted to bright cyclic light within certain ranges that did not significantly damage photoreceptor cells are protected from constant light challenge. This phenomenon is a post-developmental response that demonstrates a remarkable plasticity of the retina. The mechanism(s) underlying the ability of this adaptation/flexibility in protecting photoreceptors could involve endogenous molecules that encompass many aspects of retinal cell and molecular biology and physiology. Identification of these molecules may provide insight into the development of therapeutic approaches to treat retinal degeneration.

Utilization of potatoes for life support in space. V. Evaluation of cultivars in response to continuous light and high temperature

Twenty-four potato (Solanum tuberosum L.) cultivars from different regions of the world were evaluated in terms of their responses to continuous light (24 h photoperiod) and to high temperature (30 C) in two separate experiments under controlled environments. In each experiment, a first evaluation of the cultivars was made at day 35 after transplanting, at which time 12 cultivars exhibiting best growth and tuber initiation were selected. A final evaluation of the 12 cultivars was made after an additional 21 days of growth, at which time plant height, total dry weight, tuber dry weight, and tuber number were determined. In the continuous light evaluation, the 12 selected cultivars were Alaska 114, Atlantic, Bintje, Denali, Desiree, Haig, New York 81, Ottar, Rutt, Snogg, Snowchip, and Troll. In the high temperature evaluation, the 12 selected cultivars were Alpha, Atlantic, Bake King, Denali, Desiree, Haig, Kennebec, Norland, Russet Burbank, Rutt, Superior, and Troll. Among the cultivars selected under continuous irradiation, Desiree, Ottar, Haig, Rutt, Denali and Alaska showed the best potential for high productivity whereas New York 81 and Bintje showed the least production capability. Among the cultivars selected under high temperature, Rutt, Haig, Troll and Bake King had best performance whereas Atlantic, Alpha, Kennebec and Russet Burbank exhibited the least production potential. Thus, Haig and Rutt were the two cultivars that performed well under continuous irradiation and high temperature conditions, and could have maximum potential for adaptation to varying stress environments. These two cultivars may have the best potential for use in future space farming in which continuous light and/or high temperature conditions may exist. However, cultivar responses under combined conditions of continuous light and high temperature remains for further validation.

Increased distribution of collagen type III and reduced expression of matrix metalloproteinase 1 in patients with diverticular disease

Diverticular disease is an increasingly common clinical problem especially in Western industrialized countries, but the mechanism by which the disease develops remains unclear. Based on studies showing a structural change in the colonic wall in these patients, we examined whether there are any disorders concerning the collagen metabolism in patients with diverticular disease. Samples of colonic tissue from 13 patients with diverticulitis were compared to 14 controls. We performed a Sirius red test for the overall collagen content and immunohistochemical studies facing differentiation between collagen type I and type III and the expression of matrix metalloproteinases 1 and 13. In the bowel sections of patients with diverticulitis there were decreased levels of mature collagen type I (1.37+/- 0.32 vs. 1.59 +/- 0.31) and increased levels of collagen type III (1.61+/- 0.32 vs. 1.42 +/- 0.42), with a resulting lower collagen ratio I/III. The expression of MMP-I was reduced significantly in the diverticulitis group (4.83 +/- 0.92 vs. 6.02 +/- 1.98) while expression of MMP-13 did not differ significantly between the two groups (1.03 +/- 0.11 vs. 1.04 +/- 0.12). Our findings support the theory of structural changes in the colonic wall as one of the major pathogenic factors in the development of diverticular disease. Further studies must focus on the complex interactions of several extracellular matrix components.

Myosin light chain kinase- and PKC-dependent contraction of LES and esophageal smooth muscle

In smooth muscle cells enzymatically isolated from circular muscle of the esophagus (ESO) and lower esophageal sphincter (LES), ACh-induced contraction and myosin light chain (MLC) phosphorylation were similar. Contraction and phosphorylation induced by purified MLC kinase (MLCK) were significantly greater in LES than ESO. ACh-induced contraction and MLC phosphorylation were inhibited by calmodulin and MLCK inhibitors in LES and by protein kinase C (PKC) inhibitors in ESO. Contraction of LES and ESO induced by the PKC agonist 1,2-dioctanoylglycerol (DG) was unaffected by MLCK inhibitors. Caldesmon and calponin concentration-dependently inhibited ACh-induced contraction of ESO and not LES. In ESO, caldesmon antagonist GS17C reversed caldesmon- but not calponin-induced ACh inhibition. GS17C caused contraction of permeabilized ESO but had much less effect on LES. GS17C-induced contraction was not affected by MLCK inhibitors, suggesting that MLCK may not regulate caldesmon-mediated contraction. DG-induced contraction of ESO and LES was inhibited by caldesmon and calponinin, suggesting that these proteins may regulate PKC-dependent contraction. We conclude that calmodulin and MLCK play a role in ACh-induced LES contraction, whereas the classical MLCK may not be the major kinase responsible for contraction and phosphorylation of MLC in ESO. ESO contraction is PKC dependent. Caldesmon and/or calponin may play a role in PKC-dependent contraction.

Multiple cleavage activities of endonuclease V from Thermotoga maritima: recognition and strand nicking mechanism

Endonuclease V is a deoxyinosine 3'-endonuclease which initiates removal of inosine from damaged DNA. A thermostable endonuclease V from the hyperthermophilic bacterium Thermotoga maritima has been cloned and expressed in Escherichia coli. The DNA recognition and reaction mechanisms were probed with both double-stranded and single-stranded oligonucleotide substrates which contained inosine, abasic site (AP site), uracil, or mismatches. Gel mobility shift and kinetic analyses indicate that the enzyme remains bound to the cleaved inosine product. This slow product release may be required in vivo to ensure an orderly process of repairing deaminated DNA. When the enzyme is in excess, the primary nicked products experience a second nicking event on the complementary strand, leading to a double-stranded break. Cleavage at AP sites suggests that the enzyme may use a combination of base contacts and local distortion for recognition. The weak binding to uracil sites may preclude the enzyme from playing a significant role in repair of such sites, which may be occupied by uracil-specific DNA glycosylases. Analysis of cleavage patterns of all 12 natural mismatched base pairs suggests that purine bases are preferrentially cleaved, showing a general hierarchy of A = G > T > C. A model accounting for the recognition and strand nicking mechanism of endonuclease V is presented.

Improved ultrasonic spectroscopy methods for characterization of dispersive materials

Transmission ultrasonic spectroscopy method has been successfully implemented for the characterization of piezoceramics at high frequencies. There are, however, still some intrinsic error sources that limit the accuracy of the method. In this paper, two improved ultrasonic spectroscopy methods are presented, which can reduce the number of pre-required parameters and reduce another error source. The two improved methods were used to measure the frequency dispersion of phase velocity and attenuation of doped piezoceramic lead zirconate titanate (PZT-5A); results were compared with those obtained from the conventional method. The advantages and limitations of each method are discussed.

Protective effect of XY99-5038 on hydrogen peroxide induced cell death in cultured retinal neurons

XY99-5038 is a preparation from a specific formula provided by Dr. Yan Xin, a renowned Traditional Chinese Medicine specialist. This formulation has proven to be effective without side effects but has not been studied under rigorous laboratory conditions. In order to investigate the role of XY99-5038 in protecting neurons from degeneration, we used retinal neuronal culture as a model system to study the protective effects of XY99-5038 against hydrogen peroxide (H2O2) induced cytotoxicity. Basic fibroblast growth factor (bFGF), a potent neurotrophic factor, was employed as comparable agent. Retinas of 0-2 days old Sprague-Dawley rats were isolated, dissociated, and the neurons maintained for 2 weeks in a synthetic serum-free media. Cytotoxicity was determined by MTT (3,(4,5-dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide) and LDH (Lactate dehydrogenase) assays, whereas apoptotic cell death was evaluated by the TUNEL (TdT-mediated digoxigenin-dUTP nick-end labeling) assay. Treatment with H2O2 significantly induced death of retinal neurons. Pretreatment with XY99-5038 prior to insult greatly inhibited or attenuated H2O2 induced cytotoxicity and apoptosis. These effects were shown to be dose-dependent. Our data also show that the protective effect of XY99-5038 is more potent than that of bFGF. Our data suggest that XY99-5038 could be a potential agent in the treatment of disorders associated with oxidative damage.

In vivo protection of photoreceptors from light damage by pigment epithelium-derived factor

PURPOSE

To determine whether pigment epithelium-derived factor (PEDF) exhibits neurotrophic and neuroprotective activities in vivo for photoreceptor cells.

METHODS

Sprague-Dawley albino rats were injected intravitreally with 2 microg PEDF or a mixture of 1 microg basic fibroblast growth factor (bFGF)/1 microg PEDF in a volume of 1 microl phosphate-buffered saline (PBS). Animals were exposed to constant light for different periods at an illuminance level of 1200 to 1500 lux. The electroretinogram (ERG) waveforms of both eyes in the same animal were simultaneously recorded to evaluate functional protection. The morphologic protection was evaluated by quantitative histology.

RESULTS

Intravitreal injection of PEDF before exposure to constant light resulted in significant morphologic and functional protection of photoreceptor cells in the retina of light-damaged rats. This protection depended on the duration and severity of light damage. The protection was eliminated by extending the light exposure to 10 days. Injection of PEDF at 0, 1, and 2 days after constant light exposure did not provide significant protection above that seen in PBS-injected eyes. Combination of PEDF with bFGF improved functional protection of photoreceptor cells.

CONCLUSIONS

The data demonstrate that PEDF protected photoreceptor cells against light damage. This is significant, because it may open new avenues for the study of molecular mechanisms underlying degenerative processes. This, in turn, may lead to the development of therapeutic strategies for the prevention and treatment of degenerative diseases of the retina.

[New progress of surface enhanced Raman spectroscopic studies on a gold electrode in a nonaqueous system]

Based on a highly sensitive new generation confocal microprobe Raman system, the adsorption behavior of thiocyanate (SCN-) on a gold electrode in methanol solution was investigated by SERS for the first time. Preliminary results demonstrated that the interaction between SCN- and the electrode is so strong that its SERS signal can be detected in the whole research potential region (-0.1 V(-)-1.4 V). The orientation change may occur in the potential range -0.6 V-0.7 V. From -0.1 V to -0.6 V SCN- is adsorbed mainly through S end onto Au surface while in the potential range of -0.7 V to -1.2 V it is oriented mainly through N end. The potential dependence of the Raman frequency of nu CN resulted in two different values of electrochemical Stark effect, suggesting the existence of molecular orientation change.

beta-Adrenergic activation of p38 MAP kinase in adipocytes: cAMP induction of the uncoupling protein 1 (UCP1) gene requires p38 MAP kinase

Because of increasing evidence that G protein-coupled receptors activate multiple signaling pathways, it becomes important to determine the coordination of these pathways and their physiological significance. Here we show that the beta(3)-adrenergic receptor (beta(3)AR) stimulates p38 mitogen-activated protein kinase (p38 MAPK) via PKA in adipocytes and that cAMP-dependent transcription of the mitochondrial uncoupling protein 1 (UCP1) promoter by beta(3)AR requires p38 MAPK. The selective beta(3)AR agonist CL316,243 (CL) stimulates phosphorylation of MAP kinase kinase 3/6 and p38 MAPK in a time- and dose-dependent manner in both white and brown adipocytes. Isoproterenol and forskolin mimicked the effect of CL on p38 MAPK. In all cases activation was blocked by the specific p38 MAPK inhibitor SB202190 (SB; 1-10 microm). The involvement of PKA in beta(3)AR-dependent p38 MAPK activation was confirmed by the ability of the PKA inhibitors H89 (20 microm) and (R(p))-cAMP-S (1 mm) to block phosphorylation of p38 MAPK. Treatment of primary brown adipocytes with CL or forskolin induced the expression of UCP1 mRNA levels (6.8- +/- 0.8-fold), and this response was eliminated by PKA inhibitors and SB202190. A similar stimulation of a 3.7-kilobase UCP1 promoter by CL and forskolin was also completely inhibited by PKA inhibitors and SB202190, indicating that these effects on UCP1 expression are transcriptional. Moreover, the PKA-dependent transactivation of the UCP1 promoter, as well as its sensitivity to SB202190, was fully reproduced by a 220-nucleotide enhancer element from the UCP1 gene. We similarly observed that increased phosphorylation of ATF-2 by CL was sensitive to both H89 and SB202190, while phosphorylation of cAMP-response element-binding protein was inhibited only by H89. Together, these studies illustrate that p38 MAPK is an important downstream target of the beta-adrenergic/cAMP/PKA signaling pathway in adipocytes, and one of the functional consequences of this cascade is stimulation of UCP1 gene expression in brown adipocytes.

Water penetration and binding to ferric myoglobin

Flash photolysis investigations of horse heart metmyoglobin bound with NO (Mb(3+)NO) reveal the kinetics of water entry and binding to the heme iron. Photodissociation of NO leaves the sample in the dehydrated Mb(3+) (5-coordinate) state. After NO photolysis and escape, a water molecule enters the heme pocket and binds to the heme iron, forming the 6-coordinate aquometMb state (Mb(3+)H2O). At longer times, NO displaces the H2O ligand to reestablish equilibrium. At 293 K, we determine a value k(w) approximately 5.7 x 10(6) s(-1) for the rate of H2O binding and estimate the H2O dissociation constant as 60 mM. The Arrhenius barrier height H(w) = 42 +/- 3 kJ/mol determined for H2O binding is identical to the barrier for CO escape after photolysis of Mb(2+)CO, within experimental uncertainty, consistent with a common mechanism for entry and exit of small molecules from the heme pocket. We propose that both processes are gated by displacement of His-64 from the heme pocket. We also observe that the bimolecular NO rebinding rate is enhanced by 3 orders of magnitude both for the H64L mutant, which does not bind water, and for the H64G mutant, where the bound water is no longer stabilized by hydrogen bonding with His-64. These results emphasize the importance of the hydrogen bond in stabilizing H2O binding and thus preventing NO scavenging by ferric heme proteins at physiological NO concentrations.

Development of normal and injury-induced gene expression of aFGF, bFGF, CNTF, BDNF, GFAP and IGF-I in the rat retina

Focal mechanical injury to the retina substantially increases basic fibroblast growth factor (bFGF) and ciliary neurotrophic factor (CNTF) mRNA expression, accompanied by a transient increase in FGFR-1 mRNA, and this response is thought to protect photoreceptors near the injury site from inherited and light-induced retinal degenerations. We have now examined retinal gene expression of the principal survival factors involved in the response to injury in normal rats as a function of postnatal age both in normal and injured retinas. Sprague-Dawley rats were injured in one eye by needle incision through the retina at postnatal day (P) 10, 22, 35, 60, 90, 120 and 180. The other eye was uninjured and served as the control. Retinas were taken 1 day post-injury. Northern blot analysis was performed to determine the mRNA expression of the following factors and receptors: bFGF and acidic fibroblast growth factors (aFGF) and FGF receptor-1 (FGFR-1); CNTF and CNTF receptor alpha (CNTFR-alpha); brain-derived neurotrophic factor (BDNF) and its receptor trk B; and insulin-like growth factor-I (IGF-I) and IGF-I receptor (IGF-IR); glial fibrillary acidic protein (GFAP) and opsin. In the uninjured control eyes, mRNA expression of most of the factors increased with postnatal age, with little expression at P10 and maximal expression levels reached at P22 (opsin), P35 (aFGF), P60 (BDNF) or P90 (bFGF, FGFR-1, CNTF and GFAP). In contrast, IGF-1 mRNA rapidly decreased from a high level of expression at P10 to about 55% of that level by P22, reaching a stable 45-50% of the P10 level at P35 and thereafter. The response to injury of bFGF, FGFR-1, CNTF and GFAP mRNAs increased with postnatal age. Unexpectedly, only minimal increases in bFGF, FGFR-1, CNTF and GFAP over those seen in the control eyes were observed before P35. Thereafter, the increase of bFGF mRNA after injury reached a maximum of three-fold at P60, maintained this level to P120, and slightly decreased to 2.5-fold by P180. Expression of FGFR-1 mRNA showed a maximum increase of 2.6-fold at P90. Expression of CNTF and GFAP mRNAs followed a time course similar to that of bFGF. Mechanical injury did not alter the mRNA levels of aFGF, BDNF, IGF-I, and receptors, CNTFR-alpha, trk B and IGF-IR. These data show that the response to injury is minimal at early postnatal ages but increases with age and peaks at P60-90 for most potential survival factors.

[Investigations on Human ehrlichia infectious people in Daxingan Mountains]

OBJECTIVE

In order to investigate the prevalence of Human ehrlichia infectious people in Daxingan Mountains.

METHODS

Using PCR detection, followed by sequence analysis to detect EC and Human granulocytic ehrlichia from people in Daxingan Mountains applying the 16S rRNA gene primers of the two agents.

RESULTS

Specific 16S rRNA gene sequences of EC and HGE agent were amplified from human blood specimens of tick-bitted patients and woodsmen. The detected HGE agent 16S rRNA gene (1 433 bp) amplified from a blood specimen of a tick-bitted patient differed in only one base compared with that of an American HGE agent strain.

CONCLUSION

It was considered that Human ehrlichia infectious people did exist in Daxingan Mountains.

[Cost-effectiveness analysis of hepatitis B vaccination in People's Liberation Army]

OBJECTIVE

To select an optimal vaccination approach and provide basis for decision-making on the control of hepatitis B infection in PLA.

METHODS

Decision trees were constructed. The yearly new infection rate in susceptible cohort, using a catalytic model, was estimated. Disability-adjusted life year (DALY) was used to assess the effectiveness. Incremental cost-effectiveness ratio (CER) was then calculated.

RESULTS

Compared with no vaccination, DALY of immediate vaccination and vaccination after screening were 61.89 and 57.18 with CER 392.70 and 251.90 respectively. After weighting with actual age construction of PLA population, the CERs of vaccination after screening and immediate vaccination were 251.90 and 392.70 respectively.

CONCLUSION

The results indicated that screening followed by vaccination was superior to immediate vaccination approach. The younger the vaccination was carried out, the more cost-effective was shown by vaccination.

[Spectral analysis on self-assembly ultrathin film of polyaminobenzonitrile]

Poly(p-amino benzonitrile) (PABN) was synthesized by the method of plasma polymerization. With the self-assembly techniques, an ultrathin film of PABN and NaPSS (sodium polystyrene sulfonate) was successfully prepared. UV-Visible absorption spectra revealed that the film is very regular. This is a new method to prepare ultrathin film of PABN.

[Effects of different varieties and sowing dates on development stages of wheat]

The effects of different sowing dates and varieties on development stages of wheat were studied in this paper. The results showed that the emergence of tiller was mainly regulated by the ecological factors rather than the genetic effect. For winter-type variety(Jing 411), most variable growth duration throughout the entire growth cycle occurred from tillering to jointing. In contrast, the timing of single ridge stage was determined by genotypic effect rather than ecological factors. Single ridge to double ridge stage was most sensitive to vernalization progress. For spring sowing of winter-type variety, the vernalization process could last till floral primordium differentiation stage. The corresponding relationships existed between phenological and spike development stages in different sowing dates, although a little variable. Winter-type variety had more ecologically variable leaf primoudia, due to its stronger vernalization requirement. For winter-type variety, the primordium numbers of reproductive organs were not apparently related to the GDD accumulated prior to vernalization completion, while for spring-type variety(Yangmai 158), the numbers of different apex primordia including vegetative and reproductive organs were significantly related to the accumulated GDD during the entire phenological stages as well as before anther separation stage.

Ca2+-induced contraction of cat esophageal circular smooth muscle cells

ACh-induced contraction of esophageal circular muscle (ESO) depends on Ca2+ influx and activation of protein kinase Cepsilon (PKCepsilon). PKCepsilon, however, is known to be Ca2+ independent. To determine where Ca2+ is needed in this PKCepsilon-mediated contractile pathway, we examined successive steps in Ca2+-induced contraction of ESO muscle cells permeabilized by saponin. Ca2+ (0.2-1.0 microM) produced a concentration-dependent contraction that was antagonized by antibodies against PKCepsilon (but not by PKCbetaII or PKCgamma antibodies), by a calmodulin inhibitor, by MLCK inhibitors, or by GDPbetas. Addition of 1 microM Ca2+ to permeable cells caused myosin light chain (MLC) phosphorylation, which was inhibited by the PKC inhibitor chelerythrine, by D609 [phosphatidylcholine-specific phospholipase C inhibitor], and by propranolol (phosphatidic acid phosphohydrolase inhibitor). Ca2+-induced contraction and diacylglycerol (DAG) production were reduced by D609 and by propranolol, alone or in combination. In addition, contraction was reduced by AACOCF(3) (cytosolic phospholipase A(2) inhibitor). These data suggest that Ca2+ may directly activate phospholipases, producing DAG and arachidonic acid (AA), and PKCepsilon, which may indirectly cause phosphorylation of MLC. In addition, direct G protein activation by GTPgammaS augmented Ca2+-induced contraction and caused dose-dependent production of DAG, which was antagonized by D609 and propranolol. We conclude that agonist (ACh)-induced contraction may be mediated by activation of phospholipase through two distinct mechanisms (increased intracellular Ca2+ and G protein activation), producing DAG and AA, and activating PKCepsilon-dependent mechanisms to cause contraction.

Exploring the catalytic center of TaqI endonuclease: rescuing catalytic activity by double mutations and Mn2+

TaqI is a metal-dependent endonuclease that recognizes T(downward arrow)CGA, with the arrow indicating the cleavage site. Mutations at K158 render the enzyme inactive and mutations at K157 significantly reduce DNA cleavage activity (W. Cao and F. Barany (1998) J. Biol. Chem. 273, 33002-33010). Aspartate, glutamate, and histidine substitutions were made at K158 in the wild-type and K157S mutant TaqI endonuclease to understand the functional organization of the active site. None of the mutants was active with Mg(2+), but the DNA cleavage activities were partly rescued by Mn2+ for K157S-K158E and K157S-K158H mutants. The rescuing effects were observed with Mn2+ but not with other divalent cations. K157S-K158E required higher Mn2+ concentrations than the wild-type enzyme for DNA cleavage activity, suggesting that a Mn2+ ion is weakly bound at the 158 position. The need to neutralize K157 to recover the catalytic activity of K158E and K158H indicates that K158 and K157 may interact functionally. In analogy with EcoRV, Ca2+ stimulated Mn2+-mediated cleavage for the wild-type TaqI, suggesting the existence of at least two metal ions at the catalytic center. A catalytic mechanism involving two metal ions and the K157-K158 pair is proposed for TaqI endonuclease.

In vitro inhibition of antirecoverin immunoglobulin-mediated death of mammalian photoreceptor cells

Cancer-associated retinopathy (CAR) is a blinding disease, which can be mediated by autoimmune reactions with a specific calcium-binding retinal protein, recoverin. A number of recent studies demonstrate that agents that mobilize intracellular calcium can protect neurons from apoptotic death induced by a variety of insults. In this study, we investigated the effect of one such agent, potassium, on the survival of mammalian rod photoreceptors exposed to antirecoverin IgG. Primary cell cultures of rat retinal neurons were grown in a chemically defined medium, and cells were exposed to antirecoverin IgG for 72 hr in various concentrations of potassium and the surviving cells counted. Rod photoreceptors were quantitated using antirhodopsin immunofluorescence microscopy, and total cell numbers were determined by 4',6-diamidino-2-phenylindole (DAPI) staining of nuclei. Apoptosis was evaluated by TdT-mediated biotin-dUTP nick-end labeling (TUNEL), cell death-detection ELISA, and DNA laddering. The present study shows that elevated extracellular K+ ([K+](o)) protects retinal neurons from antirecoverin antibody-mediated cell death. The protective effects of ([K+](o)) were shown to be time- and dose-dependent. The inhibition of antirecoverin IgG-mediated death of photoreceptors by elevated ([K+](o)) suggests that the mobilization of internal calcium stores rescues the cells by interfering with apoptotic signal transduction pathways. These data also suggest that the death of photoreceptor cells occurring in CAR possibly can be prevented by reagents and/or environmental changes that mobilize intracellular calcium.

Differences in affinity of binding of lymphocytic choriomeningitis virus strains to the cellular receptor alpha-dystroglycan correlate with viral tropism and disease kinetics

alpha-Dystroglycan (alpha-DG) was recently identified as a receptor for lymphocytic choriomeningitis virus (LCMV) and several other arenaviruses, including Lassa fever virus (W. Cao, M. D. Henry, P. Borrow, H. Yamada, J. H. Elder, E. V. Ravkov, S. T. Nichol, R. W. Compans, K. P. Campbell, and M. B. A. Oldstone, Science 282:2079-2081, 1998). Data presented in this paper indicate that the affinity of binding of LCMV to alpha-DG determines viral tropism and the outcome of infection in mice. To characterize this relationship, we evaluated the interaction between alpha-DG and several LCMV strains, variants, and reassortants. These viruses could be divided into two groups with respect to affinity of binding to alpha-DG, dependence on this protein for cell entry, viral tropism, and disease course. Viruses that exhibited high-affinity binding to alpha-DG displayed a marked dependence on alpha-DG for cell entry and were blocked from infecting mouse 3T6 fibroblasts by 1 to 4 nM soluble alpha-DG. In addition, high-affinity binding to alpha-DG correlated with an ability to infiltrate the white pulp (T-dependent) area of the spleen, cause ablation of the cytotoxic T-lymphocyte (CTL) response by day 7 postinfection, and establish a persistent infection. In contrast, viruses with a lower affinity of binding to alpha-DG were only partially inhibited from infecting alpha-DG(-/-) embryonic stem cells and required a concentration of soluble alpha-DG higher than 100 nM to prevent infection of mouse 3T6 fibroblasts. These viruses that bound at low affinity were mainly restricted to the splenic red pulp, and the host generated an effective CTL response that rapidly cleared the infection. Reassortants of viruses that bound to alpha-DG at high and low affinities were used to map genes responsible for the differences described to the S RNA, containing the virus attachment protein glycoprotein 1.

High frequency properties of passive materials for ultrasonic transducers

The acoustic properties of passive materials for ultrasonic transducers have been measured at room temperature in the frequency range from 25 to 65 MHz using ultrasonic spectroscopy. These materials include alumina/EPO-TEK 301 composites and tungsten/EPO-TEK 301 composites. Experimental results showed that the acoustic impedance of the composites monotonically increased with the volume fraction of the particle filler, which is in agreement with the Denavey model. The attenuation, however, peaked between 7 and 9% volume fraction of particle filler. For comparison, several other passive materials were also fabricated and measured. The results suggest that materials that possess a higher attenuation also appear to have a larger velocity dispersion.

Direct binding of activated c-Src to the beta 3-adrenergic receptor is required for MAP kinase activation

Both beta(2)- and beta(3)-adrenergic receptors (ARs) are able to activate the extracellular signal-regulated kinase (ERK) pathway. We previously showed that c-Src is required for ERK activation by beta(2)AR and that it is recruited to activated beta(2)AR through binding of the Src homology 3 (SH3) domain to proline-rich regions of the adapter protein beta-arrestin1. Despite the absence of sites for phosphorylation and beta-arrestin binding, ERK activation by beta(3)AR still requires c-Src. Agonist activation of beta(2)AR, but not beta(3)AR, led to redistribution of green fluorescent protein-tagged beta-arrestin to the plasma membrane. In beta-arrestin-deficient COS-7 cells, beta-agonist-dependent co-precipitation of c-Src with the beta(2)AR required exogenous beta-arrestin, but activated beta(3)AR co-precipitated c-Src in the absence or presence of beta-arrestin. ERK activation and Src co-precipitation with beta(3)AR also occurred in adipocytes in an agonist-dependent and pertussis toxin-sensitive manner. Protein interaction studies show that the beta(3)AR interacts directly with the SH3 domain of Src through proline-rich motifs (PXXP) in the third intracellular loop and the carboxyl terminus. ERK activation and Src co-precipitation were abolished in cells expressing point mutations in these PXXP motifs. Together, these data describe a novel mechanism of ERK activation by a G protein-coupled receptor in which the intracellular domains directly recruit c-Src.

[Two-dimensional surface Raman imaging of a roughened iron electrode in saline solution]

By using a confocal microprobe Raman system and proper surface roughening procedure for iron, the pit corrosion behavior of bare iron electrode in 3.4% NaCl (saline solution) solution has been investigated. The surface-enhanced Raman scattering (SERS) spectra of the corrosion products due to the pit corrosion at positive potential was obtained with high ratio of signal to noise. The application of SERS technique has been extended successfully to the study of iron corrosion. The two-dimensional surface Raman imaging acquired at 660 cm-1 was obtained also with the utility of surface Raman image technique. Results show that different iron oxides should coexist in the pit corrosion region and the distribution of the corrosion products was not uniform.

Group I secreted PLA2 in the maintenance of human lower esophageal sphincter tone

BACKGROUND & AIMS

In cat spontaneous lower esophageal sphincter (LES), tone is maintained by the activity of group I secreted phospholipase A2 (sPLA2-I) that produces arachidonic acid. Arachidonic acid metabolites activate G proteins linked to phospholipases, producing second messengers and activation of a protein kinase C-dependent pathway to maintain tone. We examined the role of sPLA2-I in the maintenance of tone in human LES samples obtained from organ donors.

METHODS

In vitro LES tone and sPLA2-I-induced contraction of enzymatically isolated LES smooth muscle cells were measured in the absence or presence of inhibitors. Cell permeabilization by saponin allowed use of G-protein antibodies.

RESULTS

In vitro LES tone was reduced by inhibitors of sPLA2-I, by indomethacin, by the phosphatidylcholine-specific phospholipase C inhibitor D609, and by the protein kinase C inhibitor chelerythrine. sPLA2-I-induced contraction of isolated LES smooth muscle cells was reduced by indomethacin, pertussis toxin, Gi3 antibodies, D609, and by chelerythrine.

CONCLUSIONS

Human LES tone is maintained by the activity of sPLA2-I that produces arachidonic acid and metabolites and activation of Gi3-linked receptors and of phosphatidylcholine-specific phospholipase C, resulting in production of diacylglycerol, activation of PKC, and maintenance of tone through a protein kinase C-dependent contractile pathway.

Arg485Lys polymorphism of factor V increases the risk of coronary artery disease in a Chinese population

OBJECTIVE

To explore the relationship between genetic variation in coagulation factor V and the occurrence of coronary arterial disease (CAD).

METHODS

Unrelated 86 patients with CAD and 102 healthy controls were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) to detect variations in the entire twenty-five exons of the factor V gene.

RESULTS

Polymorphisms in exon 4 [642 G-->T (Ser156)], exon 10 [1628 G-->A (Arg485Lys)], exon 13 [4070 A-->G (His1299Arg)] and exon 16 [5380 G-->A (Val1736Met)] were documented. The study also identified a novel polymorphism in exon 2 (327 A-->G) which did not result in amino acid residue substitution. The Leiden mutation (Arg506Gln) was not detected in any of our 188 subjects. Among the 5 polymorphisms, the allele frequency of 1628 G-->A was significantly different between CAD patients and controls (0.69 vs 0.81, chi 2 = 6.908, P < 0.01). This is the first report of this finding in a Chinese population.

CONCLUSION

1628 G-->A polymorphism is associated with CAD and it may be a risk factor for CAD morbidity in the Chinese population.

Determination of average crystallite shape by X-ray diffraction and computational methods

The objective of this work was to develop a method to estimate the average shape and habit of organic crystalline material using X-ray powder diffraction (XRPD), the single-crystal structure, and computational methods. It is proposed that the relative intensities of the peaks in an XRPD pattern from a sample exhibiting a "standard" preferred orientation correlates with the shape of the crystallites present. Models were developed to yield a quantitative "enhancement" factor for each face. The combined simple-forms morphology (CSM) of the material was then produced by indexing the observed faces and modifying the simulated Bravais-Friedel-Donnay-Harker (BFDH) morphology. The average shape of crystallites can be estimated from the CSM by multiplying each face by its enhancement factor. Acetaminophen crystals in two different habits and ibuprofen crystallized from toluene were used. The predicted shapes closely resembled the average shapes observed with microscopy. Results suggested the average shapes of the organic crystalline materials can be estimated by XRPD and the computational simulation. The current limitations are the need to "index" the faces, the size of the crystallites, and the unknown impact of a polydisperse size distribution on the calculation. The method must be used within the limits described; however, it is the only method found that may be adapted to large, more representative sample sizes. The determination of the average morphology is often a "bottle neck" in elucidating other important behaviors of large quantities of crystalline powders used in pharmaceutical development and processing.

[Microwave heating modulation of skin fibrosis in chronic extremity lymphedema]

OBJECTIVE

To observe the effects of microwave heating on skin fibrosis in chronic extremity lymphedema.

METHODS

Skin specimens from 8 cases of chronic limb lymphedema were tested by in situ hybridization (ISH) combined with avidin-biotin peroxidase (ABC) immunohistochemistry for detection of TGF-beta, procollagen I, procollagen III mRNAs and corresponding peptides expressions.

RESULTS

It was discovered that expressions of TGF-beta 1 peptide were located at the spinous and granular layer of the epidermal cells with a great amount of dermal collagen I, III formation in accordance with high expressions of TGF-beta, procollagen I, procollagen III mRNAs in the dermal and subcutaneous tissue fibroblasts. After microwave heating treatment, the epidermal expression of TGF-beta 1 and relative TGF-beta, procollagen I, procollagen III mRNAs expressions in dermal fibroblasts were greatly reduced. The smaller calibre of collagen fibers after microwave heating was also observed.

CONCLUSIONS

It is indicated that fibrosis in lymphedema is resulted from overexpressions of relevant genes like TGF-beta and subsequent extracellular matrixes (ECM) syntheses and deposition. Microwave heating can reduce fibroblast expressions of TGF-beta, procollagen I, procollagen III mRNAs as well as TGF-beta peptide synthesis, inhibiting ECM syntheses and deposition and finally reverse the skin fibrosis process.

[Study on the mortality of injury in Chinese population in urban and rural areas from 1990 to 1997]

OBJECTIVE

To describe the characteristics and trend of injuries among urban and rural Chinese population.

METHODS

Data from annual Chinese national health statistics (1990 - 1997) were analyzed.

RESULTS

The overall mortality of injury in China increased from 36.8/10(6) to 76.7/10(6) from 1990 to 1997. Injury was the forth leading causes of death in urban areas and the fifth in rural areas. The death rate of injury declined in the urban while increasing in the rural areas. The rural death rate of injury was about two times of that in urban and the difference was increasing over time. The death rate of men was higher than that of women and the ratio was 1.3 - 1.9. Children below 4 years old and people above 60 years old showed the highest rates. The first three leading causes of death of injuries in urban areas were traffic accident, suicide and fall, while in rural areas were suicide, traffic accident and drowning. The death rate caused by suicide was 6.5/10(6) - 27.1/10(6) and the rate in rural areas was 2.7 to 4.0 times of that in urban areas. The mortality of suicide declined in urban while increased in rural areas. The mortality of traffic accidents had a tendency of increase in both urban and rural areas.

CONCLUSION

Injury has been one of the leading cause of death but without effectively control programs for population in Urban and Rural areas in China, special in rural areas.

Gender- and height-related limits of muscle strength in world weightlifting champions

To assess factors that limit human muscle strength and growth, we examined the relationship between performance and body dimensions in the world weightlifting champions of 1993-1997. Weight lifted varied almost exactly with height squared (Ht(2.16)), suggesting that muscle mass scaled almost exactly with height cubed (Ht(3.16)) and that muscle cross-sectional area was closely correlated with body height, possibly because height and the numbers of muscle fibers in cross section are determined by a common factor during maturation. Further height limitations of muscle strength were shown by only one male champion >/=183 cm and no female champions >/=175 cm. The ratio of weight lifted to mean body cross-sectional area was approximately constant for body-weight classes </=83 kg for men and </=64 kg for women and decreased abruptly for higher weight classes. These findings suggest a nearly constant fraction of body mass devoted to muscle in lighter lifters and a lesser fraction in heavier lifters. Analysis also suggests that contractile tissue comprises approximately 30% less body mass in female champions.

Expression of functional beta 2-adrenergic receptors in a rat airway epithelial cell line (SPOC1) and cell density-dependent induction by glucocorticoids

The beta 2-adrenergic receptor (beta 2AR) signal transduction system regulates many key functions of airway epithelium. In this study, we have pharmacologically characterized the beta 2AR and determined the impact of glucocorticoids on beta 2AR gene transcription in SPOC1 cells, a continuous cell line derived from the tracheal epithelium of rats. [125I]Cyanoiodopindolol assays demonstrated that binding to SPOC1 cell membranes was saturable (Bmax = 62.6 +/- 6 fmol/mg protein) and of high affinity (Kd = 6.3 +/- 0.8 pM). From competition experiments, the rank order of potency of agonists (isoproterenol > epinephrine >> norepinephrine) and the high affinity (Ki = 0.37 +/- 0.05 nM) of the beta 2-selective antagonist ICI 118,551 suggested the predominance of the beta 2AR subtype. Two isoforms of the alpha subunit of Gs (45 and 52 kDa) were identified by Western blot analysis. Isoproterenol-stimulated cyclic AMP levels increased in a dose-dependent manner, confirming that SPOC1 cell beta 2ARs are functionally coupled to adenylyl cyclase. The effect of glucocorticoids on beta 2AR expression was assessed in radioligand and transient transfection assays. Dexamethasone treatment of SPOC1 cells increased both beta 2AR protein and beta 2AR-luciferase fusion gene expression 1.6- to 3.1-fold, with the greatest increase demonstrated in cells cultured at low density compared to cells grown at high density.

Phylogenetic relationships of five morphological groups of hexaploid wheat (Triticum aestivum L. em Thell.) based on RAPD analysis

The genetic relationships among the five groups of hexaploid wheat: common, spelta, macha, vavilovii, and semi-wild wheat (SWW) are not clear. Random amplified polymorphic DNA (RAPD) analysis was used to assess phylogenetic relationships among these five morphological groups of hexaploid wheat. RAPD data were analyzed using the NTSYS-PC computer program to generate Jaccard genetic similarity coefficients. A dendrogram based on RAPD analysis grouped 15 accessions into five distinct clusters. These results are in agreement with those based on morphological classification, suggesting that common wheat is most closely related to SWW, followed by spelta, vavilovii, and macha.

The relationship between genetic damage from polycyclic aromatic hydrocarbons in breast tissue and breast cancer

A number of polycyclic aromatic hydrocarbons (PAH) are widespread environmental contaminants that cause mammary cancer experimentally. We investigated whether exposure and susceptibility to PAH, as measured by PAH-DNA adducts in breast tissue, are associated with human breast cancer. We carried out a hospital-based case-control study using immunohistochemical methods to analyze PAH-DNA adducts in tumor and nontumor breast tissue from cases and benign breast tissue from controls. The subjects were white, African-American and Latina women without prior cancer or treatment, including 119 women with breast cancer and 108 with benign breast disease without atypia. PAH-DNA adducts measured in breast tumor tissue of 100 cases and in normal tissue from 105 controls were significantly associated with breast cancer (OR=4.43, 96% CI 1.09-18.01) after controlling for known breast cancer risk factors and current active and passive smoking, and dietary PAH. There was substantial interindividual (17-fold) variability in adducts overall, with 27% of cases and 13% of controls having elevated adducts. The odds ratio for elevated adducts in tumor tissue compared with control tissue was 2.56 (1. 05-6.24), after controlling for potential confounders. Adduct levels in tumor tissue did not vary by stage or tumor size. Among 86 cases with paired tumor and nontumor tissue, adducts levels in these two tissues were highly correlated (r=0.56, P<0.001). However, the corresponding associations between case-control status and adducts measured in nontumor tissue from 90 cases and in normal tissue from 105 controls were positive but not statistically significant. Overall, neither active nor passive smoking, or dietary PAH were significantly associated with PAH-DNA adducts or breast cancer case-control status. These results suggest that genetic damage reflecting individual exposure and susceptibility to PAH may play a role in breast cancer; but more research is needed to determine whether the findings are relevant to causation or progression of breast cancer.

Gq-linked NK(2) receptors mediate neurally induced contraction of human sigmoid circular smooth muscle

BACKGROUND & AIMS

Because tachykinins have been identified as neurotransmitters in the guinea pig colon and human ileum, we examined a possible role of tachykinin receptors and neurokinin (NK) A in neurally induced contraction of human sigmoid colon circular muscle.

METHODS

Muscle strips were stimulated electrically for 10 seconds. Single cells were isolated by enzymatic digestion and permeabilized by saponin. [(35)S]GTPgammaS binding was assayed with or without NKA for 5 minutes. Intracellular Ca(2+) was measured using Fura 2.

RESULTS

In the presence of 100 micromol/L L-NNA, 100 micromol/L atropine did not affect electrical field stimulation (EFS)-induced contraction. A peptide NK(2)-receptor antagonist (NK-2ra) but not an NK(1) antagonist FK888 (1 micromol/L) eliminated EFS-induced contraction. NKA-induced contraction in muscle strips and single cells was virtually abolished by NK-2ra, but not by FK888. In permeabilized cells, contraction was blocked by Gq-protein antibodies, but not by other G-protein antibodies, suggesting that NKA activates Gq, which was confirmed by a [(35)S]GTPgammaS binding assay. NKA-induced contraction and increase in cytosolic Ca(2+) were abolished by depletion of intracellular Ca(2+) stores.

CONCLUSIONS

Tachykinins may be the main excitatory neurotransmitters in human sigmoid circular muscle. NKA activates Gq-linked NK(2) receptors, which cause Ca(2+) release, followed by contraction.

[Phenotypic features and genetic diversity of strains of Rhodopseudomonas]

14 strains of purple non-sulfur bacteria and 3 type strains of Rhodopseudomonas were investigated by phenotypic characterizing, DNA-DNA hybridizing and DGGE analyzing. The characteristics of their morphology, structure and physiology show that 14 strains of isolates have the features of the genus Rhodopseudomonas: dividing asymmetrically by budding, lamellar intracytoplasmic membranes, presence of bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series. On the base of their differences in morphology, growth, carbon sources 14 strains can be divided into 2 groups: g-c group, T group. Parts of 16S rRNA gene were amplified by using a pair of primers: 341f-906r. Denaturing gradient gel electrophoresis(DGGE) of PCR-amplified fragment of rDNA indicated that they have 3 genetic types: 1 of them, including 6 of 8 strains of T groups is similar to that of Rps. rutila R1, the other 2 types, represented separately by 2 of T group or all the g-c group, were different from that of either of 3 type strains The Data of the DNA-DNA hybridization of 8 representative strains indicated that the differences between different types were enough to separate them into different species including 2 possible new species.

[Community -based comprehensive prevention and control of hypertension in China (CCPACH Study)-prevalence and epidemiological characteristics in urban and rural area]

OBJECTIVE

To understand the epidemiological features and prevalence of essential hypertension in the rural communities.

METHODS

A community-based survey on essential hypertension was carried out in urban and rural areas involving 280,000 population.

RESULTS

The prevalence rate of hypertension in age 35 years and over was 31.7% and 32.9% in urban and rural respectively; the average age of the patients' in urbans was significantly higher than in rural areas. Among non-hypertensive cases, more than 50% of the population having risk factors of hypertension in both urban and rural areas. Rates of treatment and control awareness of hypertension were 56.3%, 26.8% and 4.4% respectively in urban; comparing to 40.3%, 17.5% and 2.6% respectively, in the rural areas. More than half of the diagnosed patients before survey did not take antihypertensive medicine for treatment in both areas. The proportions the classification of hypertension were similar in both areas with majority of them, mild and isolated systolic hypertension.

CONCLUSIONS

It was demonstrated that there is an urgent need to carry out comprehensive prevention and control for hypertension in urban and rural area.

[Evaluation on the effect of Benazepril for hypertension through postmarketing surveillance]

OBJECTIVE

To evaluate the efficacy and safety of Benazepril used among the essential hypertensives.

METHODS

1 831 essential hypertensive patients aged 35 to 75 were randomly selected from a community and followed for 18 months. The level of blood pressure, status of taking Benazepril and side effects were sequencially collected.

RESULTS

1/3 of the patients had taken antihypertensive drug before the study and the rate of compliance was over 96%. The effective rate of Benazepril was 73.6% at three months and increased to 84.7% at 18 months. Comparing with the baseline data, SBP and DBP declined 10.8 mmHg and 6.7 mmHg respectively. The rate of side effect was 22.7%. Cough was most commonly seen among side effects. The peak of first recording on side effect occurred at three months including 60% of them mild.

CONCLUSION

Results showed that Benazepril had good efficacy and safety for the essential hypertension patients in a long-term observation.

[A mechanistic model of phasic and phenological development of wheat. I. Assumption and description of the model]

The temperature effectiveness for wheat development was non-linearized and the apical and phenological development stages were systematically predicted by the scale of physiological development time which was based on the ecophysiological development process. The predicted apical development stages included single ridge stage, double ridge stage, floral initiation stage, stamen and pistil initiation stage, anther seperation stage, tetrad stage, and heading stage, while the predicted phenological development stages included germination stage, emergence stage, tillering stage, winterovering stage, green-turning stage, jointing stage, booting stage, heading stage, flowering stage, grain filling stage, and maturity stage. Four cultivar specific parameters were used to describe the genotypic differences of wheat development. They were temperature sensitivity, physiological vernalization time, photoperiod sensitivity, and intrinsic earliness, reflecting the genetic properties of different cultivars in thermal effectiveness, vernalization, photoperiod response and shortest time required for reaching flowering, respectively. The four parameters determined the physiological development time required for each development stage of different cultivars.

[Two-phase linear models of leaf emergence at different tillering positions in wheat and effects of different varieties and sowing dates]

Dynamics of leaf emergence shows the development progress and its relationship with growth in wheat. It was found that two-phase linear model equations (phase I faster than phase II) divided by glum differentiation stage could describe leaf emergence progress in relation to growing degree days (GDD) after sowing in wheat. This pattern was consistent in main stems and tillers of normal development with both winter-and-spring type varieties. The beginning of phase II shifted to an earlier development stage on main stems of winter type varieties of early planting (EP, September 30) and late planting (LP, March 2), and on T3 of both varieties of EP, MP (middle planting, on October 30) and LP due to their abnormal development. The thermal rate of leaf emergence on main stem was relatively high and steady during development for winter type variety of MP, and quickened with the postponing of sowing for spring type variety. The above results illustrated the difference of leaf emergence at different tillering positions, and the biological characteristics affected by different varieties and sowing dates.

[Evaluation on the effects of community-based comprehensive prevention and control of hypertension in the rural areas in China]

OBJECTIVE

To explore the strategies and measures of community-based comprehensive prevention and control of hypertension in the rural areas.

METHODS

Community-based comprehensive prevention and control of hypertension was put in practice in 120,000 people in Fangshan District of Beijing during the period of "The Ninth Five-Year Plan (1996 - 2000)".

RESULTS

After intervention, blood pressure of the whole subjects were under control and kept the level of baseline data; the rate of increase of prevalence in the intervention areas was below the rate of that from 1979 to 1991 in China (the former was 14.7%, while the latter was 53.7%); the incidence rate of the subjects was 1.4%, close to the average rate of age 15 and above in China; the rates of awareness, treatment and control were above the levels of baseline data; SBP and DBP of the patients decreased by 2.9% and 5.6%, respectively; while the rate of having high risk factors reduced by 13.4% on average.

CONCLUSION

The community-based comprehensive strategies and measures played an important and effective role in prevention and control of hypertension in rural areas.

[An genetic epidemiology study of MTHFR gene and blood level (sibpair linkage analysis)]

OBJECTIVE

To explore the relationship between MTHFR gene and blood pressure.

METHODS

A total of 142 sibpairs were collected from rural communities of CCPACH. MTHFR gene genotypes were determined by an assay based on the polymerase chain reaction. Phenotype of this study was the level of blood pressure. Covariates were measured by questionnaire, physical examination and clinical indices. Sibpair linkage analysis was used to analyse data by SAGE software.

RESULTS

In this study, prevalence of TT genotype of MTHFR gene was 9.3%, while CT was 41%. There was no evidence for linkage of the MTHFR gene with either systolic or diastolic blood pressure identified.

CONCLUSION

In our study population, MTHFR gene did not seem to be not related to blood pressure.

[Fluoride-oxide glass for high efficiency upconversion from IR to green]

In this paper, the fluoride-oxide glass doped with Er3+ for upconversion from IR to green was report. The component of sample in experiment is 60TeO2-8PbF2-10AlF3-10BaF2-10NaF-2ErO3/2, and the prepared method is obtained. The absorption spectrum was measured at room temperature. Intense green upconversion emissions from Er3+ doped the sample were observed under 808 nm and 970 nm excitation, and the upconversion emissions spectra under 808 nm and 970 nm LD excitation were measured at room temperature. The upconversion mechanics was discussed. The relationship between working currents of LD and intensity of upconversion emissions has been studied. The results was improved that needs of two photons for upconversion process under 808 nm and 970 nm excitation respectively.

[The epidemiological characteristics of multiple metabolic disorders in hypertensive patients in the communities]

OBJECTIVES

To describe the epidemiological characteristics of multiple metabolic disorders on hypertensive patients living in the communities.

METHODS

The characteristics of metabolic disorders in the hypertensives from one community in Shanghai urban area were analyzed. Metabolic disorders would include dyslipidemia (high cholesterol and/or high triglycerides and/or low HDL cholesterol), diabetes and obesity.

RESULTS

59.2% of the hypertensives at least had one metabolic disorder. Proportionally, 83.9%, 15.5%, 0.6% of the patients would combine one, two, or all of the disorders. The percentages of patients combined with dyslipidemia, diabetes and obesity were 53.0%, 9.7%, 6.3%, respectively. 74.0% of patients with metabolic disorders were combined with dyslipidemia while 9.1% were combined with both dyslipidemia and diabetes. The standardized prevalence rate of male patients with metabolic disorders was 58.1%, higher than the rate of women (54.5%). The prevalence rate of postmenopausal female patients with metabolic disorders was 67.6%, significantly higher than that of the premenopausal women (44.4%) (chi(2) = 37.49, P < 0.01).

CONCLUSION

Nearly 60% of the total patients combined with metabolic disorders. Dyslipidemia occurred in more than half of the patients in total. The proportion of senile patients with metabolic disorders was higher than the younger patients. Results suggested that attempts to maintain the coronary heart disease at low levels in the population should include treatment of dyslipidemia to keep lipid and diabetes prevalence at low levels other than regular antihypertensive therapy.

[Mutation of p53 and Ki-ras gene in human fetal lung fibroblast cells in vitro by sterigmatocystin]

To explore the carcinogenic effects of sterigmatocystin(ST), one of the predominant contaminating mycotoxins in high risk areas of cancer in China, mutation of tumor suppressor gene p53 and oncogene Ki-ras in human fetal lung cells in vitro induced by ST was studied using cell culture and silver-staining PCR-SSCP methods. The results showed that, within 22 weeks of ST treatment, no abnormalities were found for both p53 and Ki-ras gene in electrophoresis. Abnormal electrophoretic migration bands were seen at exon 8 of p53 gene and Ki-ras gene in ST-treated human lung fibroblast cells 22 weeks after ST treatment. Thus, the results further confirmed the carcinogenic effects of ST on human fetal lung tissue.