Prevalence of pollen-induced allergic rhinitis with high pollen exposure in grasslands of northern China.

BACKGROUND: The aim of this study was to investigate the prevalence of epidemiologic and physician-diagnosed pollen-induced AR (PiAR) in the grasslands of northern China and to study the impact of the intensity and time of pollen exposure on PiAR prevalence. METHODS: A multistage, clustered and proportionately stratified random sampling with a field interviewer-administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count. RESULTS: A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05). CONCLUSION: Pollen-induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.

Erratum: Impact of Tensor Force on ß Decay of Magic and Semimagic Nuclei [Phys. Rev. Lett. 110, 122501 (2013)].

This corrects the article DOI: 10.1103/PhysRevLett.110.122501.

Observation of low- and high-energy Gamow-Teller phonon excitations in nuclei.

Gamow-Teller (GT) transitions in atomic nuclei are sensitive to both nuclear shell structure and effective residual interactions. The nuclear GT excitations were studied for the mass number A = 42, 46, 50, and 54 "f-shell" nuclei in ((3)He, t) charge-exchange reactions. In the (42)Ca → (42)Sc reaction, most of the GT strength is concentrated in the lowest excited state at 0.6 MeV, suggesting the existence of a low-energy GT phonon excitation. As A increases, a high-energy GT phonon excitation develops in the 6-11 MeV region. In the (54)Fe → (54)Co reaction, the high-energy GT phonon excitation mainly carries the GT strength. The existence of these two GT phonon excitations are attributed to the 2 fermionic degrees of freedom in nuclei.

Impact of tensor force on ß decay of magic and semimagic nuclei.

The effect of the tensor force on ß decay is studied in the framework of the proton-neutron random phase approximation with the Skyrme force. The investigation is performed for even-even semimagic and magic nuclei, (34)Si, (68,78)Ni, and (132)Sn. The tensor correlation induces strong impact on the low-lying Gamow-Teller state. In particular, it improves the ß-decay half-lives. Q and ft values are also investigated and compared with experimental data.

Identification of the ß+ isovector spin monopole resonance via the 208Pb and 90Zr(t,3He) reactions at 300 MeV/u.

The double-differential cross sections for the (208)Pb and (90)Zr(t,(3)He) reactions at 300 MeV/u have been measured at the RI Beam Factory at RIKEN. This was the first physics experiment with the SHARAQ magnetic spectrometer. The combined analysis of the present (t,(3)He) data and previous (n,p) data provides the clearest identification for the ß(+) isovector spin monopole resonance both in the (208)Tl and (90)Y nuclei, and puts the observations of this giant resonance on a firm foundation. The measured distributions of the (t,(3)He) monopole cross sections were well reproduced by the distorted-wave Born approximation calculation, where the target transition density was calculated with the self-consistent Hartree-Fock plus random-phase approximation using the T43 Skyrme interaction. A major part of the expected ß(+) isovector spin monopole strength was found in the measured cross section spectra.

Effect of the tensor force on the charge exchange spin-dipole excitations of 208Pb.

The charge exchange spin-dipole (SD) excitations of 208Pb are studied by using a fully self-consistent Skyrme Hartree-Fock plus random phase approximation formalism which includes the tensor interaction. It is found, for the first time, that the tensor correlations have a unique, multipole-dependent effect on the SD excitations; that is, they produce a softening of 1{-} states, but a hardening of 0{-} and 2{-} states. This paves the way to a clear assessment of the strength of the tensor terms. We compare our results with a recent measurement, showing that our choice of tensor terms improves the agreement with experiment. The robustness of our results is supported by the analytic form of the tensor matrix elements.

Controlled orientation of individual molecules by electrode potentials.

Information storage flips molecules out: The orientation of individual molecules-vertically or horizontally on a Cu(111) surface-can be controlled in an electrolyte solution by application of an electrode potential. The transition is completely potential dependent, reversible and stable; such are the minimum requirements for computer memory devices. STM images show two orientations of an adlayer of 2,2'-bipyridine.

Molecular superlattices induced by alkyl substitutions in self-assembled triphenylene monolayers.

The configuration of the superlattices, formed from liquid-crystalline molecules on a graphite surface, are controllable through their alkyl substituents. This control may be attributed to the interplay of molecular steric interaction and the 2 D crystallization of alkyl chains. Two such lattices, as observed by STM, are shown in the accompanying graphic (C12- and (inset) C14-substituted molecules).

Family aggregation and maternal inheritance of Chinese type 2 diabetes mellitus in Taiwan.

BACKGROUND: Type 2 diabetes mellitus (DM) is a well-known familial disease, although the genetics of this complex condition remains unclear. Recent evidence suggests the significance of maternal inheritance. However, the pattern of family aggregation and the influence of other family relatives on the mode of transmission in Chinese patients with diabetes are lacking. METHODS: We interviewed 449 patients (151 men and 298 women) with type 2 DM who were aged between 35 and 74 years with a mean age of 58 +/- 1 years in a referral hospital in central Taiwan. We recorded a detailed family history of diabetes for each patient. RESULTS: Overall, 60% of diabetic patients had at least one diabetic family member. Among these index patients, 22.5% had a diabetic mother compared with 12.0% who had a diabetic father (p < 0.001). Approximately 29% of diabetic patients had at least one diabetic sister compared with 24% who had at least one diabetic brother (p = 0.13). A total of 27% of diabetic men had a diabetic mother, compared with 20% of diabetic women. Women with diabetes had more diabetic sisters than did diabetic men. In contrast, diabetic men had a significantly increased percentage of diabetic family members on the maternal side or paternal uncles or aunts than did diabetic women. The percentage of diabetic patients who had a diabetic mother decreased as their age increased. The maternal effect disappeared in the diabetic patients who were over 65 years old. Statistical differences between diabetic fathers and mothers were observed when DM was diagnosed in patients under 65 years of age. CONCLUSIONS: We documented the presence of family aggregation and significant maternal inheritance in Chinese patients with type 2 DM in Taiwan. Further prospective study is needed to monitor the offspring of diabetic parents and other relatives in order to clarify the true mode of family aggregation and maternal transmission of type 2 DM.

Investigation of the interaction between acridine orange and bovine serum albumin.

The results from the measurement of the fluorescence spectrum showing the binding characteristics of acridine orange (AO) and bovine serum albumin (BSA) are reported. It was found that the equilibrium constant k=4848.64 l mol(-1), and the number of binding sites n=0.82. Based on the mechanism of the Forster energy transference, the transfer efficiency of energy and distance between the acceptor AO and BSA were found. The interaction between AO and BSA have been verified as consistent with the static quenching procedure and the quenching mechanism is related to the energy transfer.

Formation and characteristics of an unusual lambda-DNA species.

An unusual DNA species, termed as DNA species A, has been isolated and purified from thermal-denatured lambda-DNA Hind III by Sephadex G-200 gel filtration. Our studies indicate that DNA species A is resistant to DNase I digestion and has a higher melting point. The new DNA species showed a lower absorbency at 260 nm, and a lower fluorescence quantum yield after interaction with ethidium bromide (EB) than native double-stranded lambda-DNA. CD spectrum of DNA species A consists of a broad positive band centered at 245 nm and a weak negative band at 220 nm. transmission electron microscope (TEM) visualizations showed that their lengths of DNA species A fell mainly in three regions (300-500 nm, 750-1000 nm and 1500 nm) that corresponded to three fluorescence bands in the EB-stained gels. Their apparent width and height were 65-75 nm and 2.2 nm respectively as observed by images of atomic force microscope (AFM).

Comparative studies on parallel and antiparallel duplex and triplex DNA.

Parallel strand models for base sequences d(A)10.d(T)10,d(AT)5.d(TA)5, d(G5C5).d(C5G5), d(GC)5.d(CG)5 and d(CTATAGGGAT).d(GATATCCCTA), where reverse Watson-Crick A-T pairing with two H-bonds and reverse Watson-Crick G-C pairing with one H-bond or with two H-bonds were adopted, and three models of d(T)14.d(A)14.d(T)14 triple helix with different strand orientations were built up by molecular architecture and energy minimization. Comparisons of parallel duplex models with their corresponding B-DNA models and comparisons among the three triple helices showed: (i) conformational energies of parallel AT duplex models were a little lower, while for GC duplex models they were about 8% higher than that of their corresponding B-DNA models; (ii) the energy differences between parallel and B-type duplex models and among the three triple helices arose mainly from base stacking energies, especially for GC base pairing; (iii) the parallel duplexes with one H-bond G-C pairs were less stable than those with two H-bonds G-C pairs. The present paper includes a brief discussion about the effect of base stacking and base sequences on DNA conformations.

In vitro effects of MOCA and dapsone on rat hepatic and splenic immune cells.

The industrial curing agent 4,4'-methylene-bis(2-chloroaniline) (MOCA) and the structurally related medicinal agent 4,4'-sulphonyldianiline (dapsone), are two commonly used aromatic amine compounds and documented animal carcinogens. In this study the effects of in vitro exposure to MOCA and dapsone (over a dose range of 1-200 microM on spleen and liver immune cell functions were investigated. MOCA exposure caused a dose-dependent inhibition of natural immune activities (i.e. natural killer, NK and natural P815 killer, NPK) and mitogen-stimulated proliferation of T- and B-lymphocytes, with 50% inhibition (IC50) of splenic-cell activities occurring at 145, 85, 21 and 31 microM, respectively. Liver NK and NPK activities were less sensitive to MOCA exposure and exhibited higher IC50's of 165 and 160 microM, respectively. Dapsone exposure slightly enhanced both T- and B-cell mitogenesis at low doses (1 microM) but decreased B-cell mitogenesis at high doses (IC50 = 130 microM). Natural tumouricidal activities were generally unaffected by dapsone, whilst natural cytotoxic (NC) activity was unaffected by both compounds. These results indicate that MOCA is generally immunotoxic in vitro, and may have the potential to enhance the carcinogenic effects of its genotoxic metabolite by inhibiting the tumour surveillance activities of the immune system. The relationship between immune effects and the carcinogenicity of dapsone remains unclear.

Raised concentration of serum bile acids following occupational exposure to halogenated solvents, 1,1,2-trichloro-1,2,2-trifluoroethane and trichloroethylene.

OBJECTIVES: The objectives of this study were threefold. First, to examine the hepatic effects of occupational exposure to 1,1,2-trichloro-1,2,2-trifluoroethane (FC 113) using conventional and newer tests (serum bile acids) of hepatobiliary function. Second, to assess the effects of altered work practices that included a reduced exposure to a different halogenated solvent (trichloroethylene) on the same parameters of liver function; and finally, to gather further data to support or refute the contention that serum bile acid (SBA) levels could provide a sensitive biological marker of exposure to these solvents. DESIGN: Two groups of workers (control and exposed) in an Australian steel industry participated in the study. The exposed group (n = 5-6) comprised individuals who had either exposure to FC 113 (68.2 +/- 12.6 ppm) or trichloroethylene (8.9 +/- 3.1 ppm) during the application of these solvents in a cleaning procedure, whereas the control group (n = 7-11) was composed of non-solvent-exposed office workers in the same company. The initial investigation involved exposure to FC 113 while a follow-up study was undertaken after changes in work practices were made including replacement of FC 113 with trichloroethylene (TRI). METHODS: Standard liver function tests and individual serum bile acids (ISBA) were measured before and after exposure to solvents and simultaneously in the control subjects by enzymatic methods and high performance liquid chromatography (HPLC), respectively. RESULTS: Statistical analysis of the data showed a significant increase in the concentration of total serum bile acids (TSBA), some of the subgroups of SBA, and a few of the ISBA in workers after a period of exposure to FC 113. After TRI replaced FC 113 together with other changes in work practices to give substantial reduction in exposure to solvent, a repeat study also found elevated SBA after the cleaning procedure but to a lesser extent. No other indications of adverse liver effects, as measured by conventional parameters of hepatobiliary function, were detected. CONCLUSION: Exposure to FC 113 was clearly associated with a significant rise in SBA levels, which are sensitive indicators of liver function. This finding is consistent with, and provides further support for, our previous investigations on chlorinated aliphatic hydrocarbon solvents which showed that SBA levels are a sensitive biological marker of exposure to these solvents. Changes in work practices including replacement of FC 113 resulted in a reduced effect on SBA, consistent with lower exposures.

Individual serum bile acids in apprentice spray painters in association with solvent exposure.

The effects of exposure to solvents on serum bile acids were investigated by comparing a group of apprentice vehicle spray painters (exposed group) with one of apprentice electricians. Apprentice spray painters from the study were subdivided into high- and low-solvent-exposure groups. Concentrations of individual serum bile acids (SBA) were measured and compared with conventional liver function tests (LFTs). Total, free, glycine- and taurine-conjugated SBA were consistently found to be present at higher levels in the spray painters than in the electricians, even at the beginning of the apprenticeship. Total SBA tended to increase in spray painters with increasing years of exposure during the apprenticeship, but this was significant at only one time point. No rises were observed over the sampling period in electricians. The mean values of individual and total SBA concentrations were all found to be higher in the high-exposure group than in the low-exposure group, with some differences reaching statistical significance. None of the routine liver biochemistry parameters was different between spray painters and electricians. gamma-Glutamyl transferase (GGT) was the only enzyme found to be significantly different between the high- and low-exposure groups, but all values were within the normal range. This study suggests that occupational exposure even to low levels of solvent mixtures results in increases in SBA. The increased SBA may be indicative of a subclinical liver dysfunction. Alternatively, they may reflect solvent exposure only, with the raised levels having no pathologic implication or consequence.

A molecular model of braid-like DNA structure.

The three-dimensional molecular models of DNA triple helices and triple-stranded brain-like structure were built up by molecular architecture, and their structural features and energy decomposition were examined. The results showed: (i) The base triplet is the element forming braid-like and triple helix DNA; (ii) Under specified conditions, DNA could form the triplet-stranded braid-like structure; (iii) DNA stability of the braid-like structure is less than that of the triple helix structure.

Interactions between L-arginine and L-glutamine change endothelial NO production. An effect independent of NO synthase substrate availability.

The effect of extracellular L-arginine and L-glutamine on nitric oxide (NO) release was studied in cultured bovine aortic endothelial cells and in rabbit aortic rings. Increasing L-arginine (0.01 to 10 mM) did not alter NO release from cultured endothelial cells or modify endothelium-dependent relaxation to acetylcholine in isolated vessels. L-Glutamine (0.6 and 2 mM) inhibited NO release from cultured cells (in response to bradykinin) and from aortic rings (in response to acetylcholine or ADP). L-Arginine (0.1-10 mM) dose-dependently reversed the L-glutamine inhibition of receptor-stimulated NO release in both models. In contrast to its inhibitory response to receptor-mediated stimuli, glutamine alone slightly potentiated NO release in both models when the calcium ionophore, A23187, was added. Furthermore, cultured cells incubated with L-arginine (0.01-10 mM), in the presence or absence of glutamine, released similar amounts of NO in response to A23187. L-Glutamine did not affect intracellular L-arginine levels. Neither D-glutamine nor D-arginine affected NO release or endothelium-dependent vascular relaxation. L-Glutamine had no effect on the activity of endothelial NOS assessed by L-arginine to L-citrulline conversion. These findings show that in the absence of L-glutamine, manipulating intracellular L-arginine levels over a wide range does not affect NO release. L-Glutamine in concentrations circulating in vivo may tonically inhibit receptor-mediated NO release by interfering with signal transduction. One mechanism by which L-arginine may enhance NO release is via reversal of the inhibitory effect of L-glutamine, but apparently independently of enhancing NO synthase substrate.

Mechanism of trichloroethylene-induced elevation of individual serum bile acids. II. In vitro and in vivo interference by trichloroethylene with bile acid transport in isolated rat hepatocytes.

The effects of trichloroethylene (TRI) on bile acid transport in isolated rat hepatocytes have been studied using doses ranging from 0.5 to 4.0 microliters/flask and a 20-min equilibration period. It was found that TRI caused a dose-related suppression of initial rates of uptake of cholic acid (CA) and taurocholic acid (TC) with no significant effect on enzyme leakage and intracellular potassium ion contents. Accumulation over 30 min for each of those two bile acids was also inhibited. A noncompetitive inhibition of bile acid uptake was shown as indicated by a decrease in maximum velocity (Vmax) and unchanged Michaelis constant (Km). Thirty minutes after cessation of TRI exposure in vitro the uptake of bile acids had gradually returned to normal levels. No significant interference of efflux was found in cells preloaded with either CA or TC. After dosing rats with 1 mmol/kg TRI in vivo the inhibition of uptake of CA and TC by subsequently isolated hepatocytes was not detected until 4 hr. By 16 hr uptake had returned to normal. The accumulation of bile acids was also suppressed at 4 and 8 hr. The inhibition of uptake after in vivo treatment was also noncompetitive. The data are consistent with the reversible increase of serum bile acids (SBA) in experimental animals after exposure to TRI. Furthermore, they support the contention that it is an interference with bile acid uptake, rather than actual cell damage, that is responsible for TRI-induced increases in SBA. Thus, the changes in SBA seem to be the result of interference with a physiological process rather than an event associated with significant pathological consequences.

Effects of carbon tetrachloride and chloroform on bile acid transport in isolated rat hepatocytes: Relationship to elevated serum bile acids.

The hepatotoxic effects of chlorinated hydrocarbon solvents have been well recognized for many years. More recently serum bile acids (SBA) have been considered as a sensitive indicator for the determination of liver dysfunction. However, changes in SBA could result from interference with hepatic transport processes. In this study, the effects of carbon tetrachloride (CCl(4)) and chloroform (CHCl(3)) on uptake and efflux of bile acids were examined in isolated rat liver cells to determine whether this may play a role in elevated SBA after CCl(4) or CHCl(3) treatment. Cholic acid (CA) and taurocholic acid (TC) were selected as representative bile acids known to enter hepatocytes by active transport. At none of the doses of CCl(4) and CHCl(3) investigated was there a significant change in cytoplasmic enzymes or intracellular K(+) release. CCl(4) and CHCl(3) were both found to cause a dose-related inhibition of uptake of CA and TC. Furthermore, CCl(4) and CHCl(3) were shown to increase the Michaelis constant (K(m)) but leave maximum velocity (V(max)) unchanged thus indicating competitive inhibition. The lowest doses of CCl(4) and CHCl(3) at which inhibition of initial uptake rate (V(0)) occurred for CA or TC were found to be 0.5 mul/flask (0.07 mm) or 1.0 mul/flask (0.17 mm) in cell suspensions, respectively. The inhibition of uptake could be reversed 30 min after cessation of exposure to CCl(4). No chemical-induced interference of efflux for CA or TC was found in preloaded cells. These findings indicate that interference in bile acid uptake may be involved, at least in part, in the increases in SBA in dosed animals, or workers exposed to CCl(4), CHCl(3) and perhaps other chlorinated solvents.

Effects of hexachloro-1,3- butadiene and 1,1,2,2- tetrachloroethylene on individual serum bile acids.

Rats were exposed to hexachlorobutadiene (HCBD) or tetrachloroethylene (TET) in order to determine which of these chemicals was more likely to be responsible for elevations in individual serum bile acids (SBA) found in workers exposed primarily to these two chemicals. Increases in cholic and taurocholic acids were found on exposure to high doses of HCBD. Elevations of SBA occurred right down to low exposures for TET, however, with cholic, chenodeoxycholic, and glycocholic acids being the most sensitive bile acids. Only at high doses for each chemical was there any indication of liver injury as determined by routinely used parameters such as serum enzymes or bilirubin. The data suggest that TET is likely to play a role in the elevated individual SBA in an exposure situation where both this chemical and HCBD are found.