Ca Minerals and Oral Bioavailability of Pb, Cd, and As from Indoor Dust in Mice: Mechanisms and Health Implications.

BACKGROUND: Elevating dietary calcium (Ca) intake can reduce metal(loid)oral bioavailability. However, the ability of a range of Ca minerals to reduce oral bioavailability of lead (Pb), cadmium (Cd), and arsenic (As) from indoor dust remains unclear. OBJECTIVES: This study evaluated the ability of Ca minerals to reduce Pb, Cd, and As oral bioavailability from indoor dust and associated mechanisms. METHODS: A mouse bioassay was conducted to assess Pb, Cd, and As relative bioavailability (RBA) in three indoor dust samples, which were amended into mouse chow without and with addition of CaHPO4, CaCO3, Ca gluconate, Ca lactate, Ca aspartate, and Ca citrate at 200-5,000µg/g Ca. The mRNA expression of Ca and phosphate (P) transporters involved in transcellular Pb, Cd and As transport in the duodenum of mice was quantified using real-time polymerase chain reaction. Serum 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3], parathyroid hormone (PTH), and renal CYP27B1 activity controlling 1,25(OH)2D3 synthesis were measured using ELISA kits. Metal(loid) speciation in the feces of mice was characterized using X-ray absorption near-edge structure (XANES) spectroscopy. RESULTS: In general, mice exposed to each of the Ca minerals exhibited lower Pb-, Cd-, and As-RBA for three dusts. However, RBAs with the different Ca minerals varied. Among minerals, mice fed dietary CaHPO4 did not exhibit lower duodenal mRNA expression of Ca transporters but did have the lowest Pb and Cd oral bioavailability at the highest Ca concentration (5,000µg/g Ca; 51%-95% and 52%-74% lower in comparison with the control). Lead phosphate precipitates (e.g., chloropyromorphite) were observed in feces of mice fed dietary CaHPO4. In comparison, mice fed organic Ca minerals (Ca gluconate, Ca lactate, Ca aspartate, and Ca citrate) had lower duodenal mRNA expression of Ca transporters, but Pb and Cd oral bioavailability was higher than in mice fed CaHPO4. In terms of As, mice fed Ca aspartate exhibited the lowest As oral bioavailability at the highest Ca concentration (5,000µg/g Ca; 41%-72% lower) and the lowest duodenal expression of P transporter (88% lower). The presence of aspartate was not associated with higher As solubility in the intestine. DISCUSSION: Our study used a mouse model of exposure to household dust with various concentrations and species of Ca to determine whether different Ca minerals can reduce bioavailability of Pb, Cd, and As in mice and elucidate the mechanism(s) involved. This study can contribute to the practical application of optimal Ca minerals to protect humans from Pb, Cd, and As coexposure in the environment. https://doi.org/10.1289/EHP11730.

Clinical Analysis of BRAFV600E Mutation and Its Correlation With Sonographic Image Characteristics in Papillary Thyroid Carcinoma in Chinese Coastal Areas.

This study analyzed the characteristics of BRAFV600E mutation in papillary thyroid carcinoma (PTC) in Chinese coastal areas. We intended to identify noninvasive methods to determine BRAFV600E status in thyroid nodules prior to surgery. BRAFV600E mutation and the sonographic characteristics of thyroid nodules were investigated in 670 PTC patients in our hospital. We aimed to determine the relationship between BRAFV600E mutation and the clinicopathological and sonographic imaging characteristics of PTC. The mutation rate of the BRAFV600E was 78.2%. BRAFV600E mutation was significantly associated with central node (univariate analyses, P = .005; multivariate analyses, P < .001, odds ratio [OR] = 10.255) and lateral node metastases (univariate analyses, P = .001; multivariate analyses, P < .001, OR = 22). It was less frequent in PTC coexisting with Hashimoto's thyroiditis (univariate analyses, P = .016; multivariate analyses, P < .001, OR = .034). Nodules without blood flow had a significantly higher mutation rate of BRAFV600E in PTC patients (univariate analyses, P = .026). BRAFV600E mutation was significantly associated with high suspicion in the Thyroid Imaging Reporting and Data System 5 (univariate analyses, P = .004; multivariate analyses, P = .014, OR = 6.456). Our results strongly suggest that BRAFV600E mutation plays a potential role in lymph node metastasis (central node metastasis, OR = 10.225; lateral node metastasis, OR = 22). Some sonographic imaging features might be helpful in estimating the status of BRAFV600E preoperatively.

RESEARCH ON THE ABSOLUTE MEASUREMENT AND CALIBRATION METHODS OF (250-450) KV X-RAY AIR KERMA AT NIM.

With the rapid application of nuclear technology, radiation protection is becoming more and more important. For external radiation protection, most of the national metrology institutes in the world have established the primary standard of X-ray air kerma in (10-250) kV and Cs-137 gamma ray, but the energy between 250 and 662 keV needs the establishment of traceability. To provide solution to such issue, a graphite cavity ionization chamber was constructed at National Institute of Metrology to measure the air kerma in (250-450) kV X-ray. The relative standard uncertainty of the method is 0.45%. Two different types of ionization chambers were used to measure the air kerma of N-300 radiation quality, and the result has a deviation of 0.09%.

Extreme diversity and multiple SCCmec elements in coagulase-negative Staphylococcus found in the Clinic and Community in Beijing, China.

BACKGROUND: Coagulase-negative staphylococci (CoNS) are recognized as a large reservoir of staphylococcal cassette chromosome mec (SCCmec) harboured by Staphylococcus aureus. However, data of SCCmec in CoNS are relatively absent particularly in China. METHODS: Seventy-eight CoNS clinical and 47 community isolates were collected in Beijing. PCR was performed to classify SCCmec types. Under oxacillin treatment, quantitative real-time reverse transcription PCR (qRT-PCR) was performed to compare mecA mRNA levels and mRNA half-life between isolates with single SCCmec element and those with multiple one. Their growth curves were analysed. Their bacterial cell wall integrity was also compared by performing a Gram stain. All ccr complex segments were sequenced and obtained ccr segments were analysed by phylogenetic analyses. RESULTS: All 78 clinical isolates had mecA segments compared with 38% in community isolates (total 47). Only 29% clinical isolates and 33% community isolates (among mecA positive isolates) harboured a single previously identified SCCmec type; notably, 17% clinical isolates and 28% community isolates had multiple SCCmec types. Further studies indicated that isolates with multiple SCCmec elements had more stable mecA mRNA expression compared with isolates with single SCCmec elements. CoNS with multiple SCCmec elements demonstrated superior cell wall integrity. Interestingly, phylogenetic analyses of obtained 70 ccr segments indicated that horizontal gene transfer of the ccr complex might exist among various species of clinical CoNS, community CoNS and S. aureus. CONCLUSIONS: CoNS recovered from patients carried extremely diverse but distinctive SCCmec elements compared with isolates from the community. More attention should be given to CoNS with multiple SCCmec not only because they had superior cell wall integrity, but also because CoNS and S. aureus might acquire multiple SCCmec through the ccr complex.

The Clinical Relevance of Psammoma Body and Hashimoto Thyroiditis in Papillary Thyroid Carcinoma: A Large Case-control Study.

This study aims to investigate the impact of psammoma body (PB) on papillary thyroid carcinoma (PTC), and evaluate the association among PB, Hashimoto thyroiditis (HT), and other clinicopathologic characteristics in PTC patients.We conducted a retrospective case-control study involving 1052 PTC patients who underwent total thyroidectomy or lobectomy with lymph node dissection.Psammoma body was observed in 324 out of 1052 PTC (30.8%) patients. Ultrasonographic (US) calcification (P < 0.001), multifocality of the tumor (P = 0.047), lymph node metastasis (LNM) (P < 0.001), HT (P < 0.001), and Primary tumor (T), Regional lymph nodes (N), Distant metastasis (M) staging (P = 0.001) were significantly related to the presence of PB. The presence of PB was significantly associated with US microcalcification (P < 0.001). In the subgroup with HT, compared with the patients without PB, the patients with PB exhibited a higher frequency of central LNM (54.7% vs 32.1%; P < 0.001) and US microcalcification (94.7% vs 38.8%; P < 0.001), as well as smaller tumors (0.9 ±â€Š0.6 vs 1.3 ±â€Š0.9 cm; P < 0.001). In the subgroup without HT, the patients with PB displayed a higher incidence of lateral LNM (25.8% vs 14.6%; P < 0.001), US microcalcification (87.3% vs 52.5%; P < 0.001), and extrathyroidal extension (47.2% vs 34.8%; P = 0.001), as well as larger tumors (1.3 ±â€Š0.9 vs 1.0 ±â€Š0.8 cm; P < 0.001) than without PB. Moreover, in the subgroup with PB, the PTC patients with HT showed a higher LNM (77.9% vs 57.2%; P < 0.001) and a lower frequency of extrathyroidal extension (20.0% vs 47.2%; P < 0.001) than without HT.Psammoma body is a useful predictor of aggressive tumor behavior in PTC patients. HT with PB shows more aggressive behaviors than non-HT with PB in PTC patients.

Ultrasonographic findings of triple-negative breast cancer.

OBJECTIVE: Our aim was to determine whether triple-negative breast cancer (TNBC) has distinguishing sonographic features compared to non-TNBC. METHODS: Data from 145 consecutive breast cancer patients were collected. The images were reevaluated by two dedicated breast imaging experts according to the Breast Imaging Reporting and Data System. The sonographic features of 45 TNBC patients were compared with those of 100 non-TNBC patients. RESULTS: TNBC showed a high histological tumor grade. On ultrasound, TNBC was more frequently to present as oval or round mass shape (48.9%, 17.8%; respectively), more likely to have circumscribed margins (82.2%), and less likely to show posterior attenuating (8.9%). Additionally, compared with non-TNBC, TNBC was less likely to have calcification (35.6%). CONCLUSION: TNBC has distinguishing imaging features on breast ultrasound, and more likely to be associated with benign masses. Knowledge of the distinct sonographic features would be useful in diagnosing TNBC.

Immunostimulatory and anti-neoplasm effects of a novel palindrome CpG oligodeoxynucleotide in mice.

AIM: DNAs containing unmethylated CpG motifs can stimulate innate and adaptive immunity. The aim of this study was to investigate the immunostimulatory and anti-neoplasm effects of a novel CpG oligodeoxynucleotide, ODN10, in tumor-bearing mice. METHODS: B16 melanoma-bearing C57BL/6 mice were administered ip or sc with ODN10 or conventional CpG ODN1826 on the indicated days post inoculation. The animal survival rate and the inhibitory effect on tumor growth were observed in vivo. B and T lymphocyte proliferation, natural killing cell cytotoxicity and the phagocytic ability of peritoneal macrophages from the animals were determined using [(3)H]-thymidine incorporation assay, 4-h (51)Cr release assay and neutral red chromometry method, respectively. The serum levels of IL-12, IL-4 and IgE were quantified using ELISA assays. Histological examination of tumor tissues was performed after HE staining, and the expression of PCNA, CD63, and CD80 in tumor tissues was analyzed with immunohistochemistry. RESULTS: ODN10 (1, 5 and 25 mg/kg) significantly inhibited the growth and metastasis of the tumor, and significantly prolonged the survival of tumor-bearing mice, as compared with ODN1826. The immune status was suppressed in tumor-bearing mice. Both ODN10 and ODN1826 significantly reversed the suppressed immunoactivities in tumor-bearing mice, which included promoting B and T lymphocyte proliferation, enhancing NK cell and peritoneal macrophage activities, inducing IL-12 secretion and inhibiting IL-4 and IgE secretion. Further, CpG ODNs decreased PCNA and CD63 expression while induced expression of CD80. ODN10 presented more potent activity, and displayed the most prominent immunostimulatory potential. CONCLUSION: ODN10 produces prominent immunomodulatory effects on cellular immunity in tumor-bearing mice, which might help reverse the established Th2-type responses to the Th1-type responses, thus may be used as a potent anti-tumor immunotherapy agent or adjuvant.

[Clinical features and prognosis of 188 Chinese patients with apical hypertrophic cardiomyopathy].

OBJECTIVE: To analyze the clinical characteristics and prognosis of Chinese patients with apical hypertrophic cardiomyopathy (AHCM). METHODS: A total of 188 patients with AHCM diagnosed at Fuwai Hospital were included in this retrospective study. Clinical characteristics, mortality and cardiovascular morbidity were analyzed. A multiple logistic regression was performed to adjust for potential confounding factors. RESULTS: Males predominated with a number of 139 (73.9%) in this cohort. Patient's age ranged from 15 to 81 (51.9 ± 12.6) years. There were 120 patients (63.8%) with "pure" type and 68 patients (36.2%) with "mixed" type of AHCM, 171 patients were followed up for (5.0 ± 3.0) years, cardiovascular mortality was 1.2%, 28 patients (16.4%) experienced one or more cardiovascular events. CONCLUSION: The prevalence of AHCM is high in Chinese HCM patients, pure type AHCM is more common, and AHCM patients have a benign clinical course.

[Visible-light responding BiVO4/TiO2 nanocomposite photocatalyst].

The two kinds of new nanocomposites BiVO4/TiO2 nanowires were synthesized by hydrothermal process. Their crystal structure, morphology and photocatalytic activities for degradation of methylene blue solution were characterized using various measurement techniques. The XRD results indicate that they are made up of monoclinic BiVO4 and anatase TiO2 phases. The SEM, TEM and HRTEM images show that the two samples include BiVO4 nanoparticles supported onto TiO2 nanowires. The UV-Vis absorption spectra reveal that the absorption edges of the samples exhibit red-shift in comparison with that of the pure TiO2 nanowires. The measurement results for the visible-light photodegradation of methylene blue show that the nanocomposite sample prepared from the layered titanate nanowires with Bi3+ has the highest photocatalytic activity.

[Application of local Moran's I and GIS to identify hotspots of Ni, Cr of vegetable soils in high-incidence area of liver cancer from the Pearl River Delta, South China].

The index of local Moran's I is a useful tool for identifying hotspots of soil Ni and Cr, and for classifying them into spatial clusters and spatial outliers. To identify hotspots of vegetable soils Ni and Cr in high-incidence area of liver cancer, Shunde area of Foshan City, Pearl River Delta Economic Zone, 208 topsoil samples were collected from vegetable fields to measure the contents of nickel (Ni) and chromium (Cr). The results showed that the mean concentrations of two heavy metals Ni, Cr were 33.21 mg/kg, 80.84 mg/kg, respectively, Which were 130%, 60% higher than their soil background values of Guangdong Province, respectively. Generally, Ni is partly accumulated in soil but the accumulation of Cr is not obvious at all. The local Moran's I of Ni and Cr was calculated using 3 000, 6 000, 9 000 m as distance bands, respectively. The hotspots of Ni and Cr elements in soils were identified by local Moran's I which computed based on 6 000 m; "individual hotspots" are in the north which were affected by anthropogenic factors; "regional hotspots" are in the south which were controlled by parent materials. Moreover, the distributions of "regional hotspots" of Ni, Cr are the same as that of the highest mortality rate of liver cancer, this consistence could come up with a research direction that could reveal environmental etiologic factors of liver cancer.

[Stokes and anti-stokes luminescence research of NaYF4:Eu3+, Tm3+, Yb3+].

The sample of NaYF4:Eu,Tm,Yb was synthesized by coprecipitation method. The emission of NaYF4:Eu,Tm,Yb excited by 360 nm is blue light with the peak at 452 nm from the transition of (1)D2-->(3)F4 of Tm3+. After being excited by 395 nm, NaYF4:Eu,Tm,Yb emits orange light with the peak at 591 nm originating from the transition of (5)D0-->(7)F1 of Eu3+. When excited by 409 nm, NaYF4:Eu,Tm,Yb emits red light with the peak at 613 nm from the transition of (5)D0-->(7)F2 of Eu3+. The color of upconversion luminescence of NaYF4:Eu,Tm,Yb excited by 980 nm was blue and red. The upconversion spectrum exhibits distinct emission peaks at 459, 478 and 641 nm. The blue light comes from the transition of (1)G4--(3)H6 and (1)D2-->(3)F4 of Tm3+. The absorption spectrum was also researched. The red light results from the transition of (1)G4--(3)F4 of Tm3+. The slope of the emission of 474 and 646 nm is 2.1 and 2.4 respectively. The emission of 478 and 641 nm is all due to three photon process. The structural properties of sample were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that NaYF4:Tm3+,Yb3+ prepared by coprecipitation method exhibits a hexagonal crystal.

[Upconversion luminescence properties of ZBLAN : Nd3+, Tm3+, Yb3+].

The ZBLAN : Nd3+, Tm3+, Yb3+ upconversion materials were prepared by high-temperature solid method. The concentrations of Tm3+ and Yb3+ were 0.01% and 0.3% respectively. The concentration of Nd3+ changed in the range from 0.1% to 2%. The absorption spectrum of ZBLAN : Nd3+, Tm3+, Yb3 in all samples from 300 to 1 000 nm was measured at room temperature. The upconversion emission was observed when excited by 798 nm infrared light. The material samples emitted relatively strong multi-band (the red, blue and green color) visible light. Based on the experiment, the multi-band visible spectral lines were analyzed, and the energy level transition mechanism was given. The blue light results from the transition of 1G4 --> 3 H6 of Tm3+, the green light is from the transition of 2 H7/2 --> 4 I9/2 of Nd3+, and the red light originates from the transition of 2 H11/2 --> I9/2 of Nd3+. The results show that the upconversion mechanism includes excited state absorption, energy transfer, cross relaxation and so on. The energy transfer processes between Nd3+, Tm3+ and Yb3+ ions both forward and backward prove to be the origin of upconversion emissions. The effect of rare earth doping concentration on the energy upconversion efficiency was analyzed, according to the different upconversion light emitting intensity from samples with different Tm3+ mol concentrations. The upconversion luminescence increased with the Nd3+ concentration and got its peak at 1.5%.

[Detection and analysis of CD271, CD133 and CD34 expressions in bone marrow cells by flow cytometry with three color fluorescence labelling].

This study was purposed to detect the expressions of CD271, CD133 and CD34, and to analyze the correlation of CD271 with CD133 and CD133 with CD34 expressions. The human bone marrow cells (BMCs) and mononucleated cells (MNCs) were detected by flow cytometry with CD45-PerCP, CD271-FITC, CD133-PE and CD34-FITC labelling according to different combinations of design, cells were located and selected repeatedly by FSC, SSC and CD45 after acquirement, then the expressions of CD271, CD133 and CD34 were detected by flow cytometry. The results showed that the expressions of CD271, CD133 and CD34 in BMCs were 0.16%, 0.20% and 0.43% respectively, while their expressions were 0.49%, 0.47% and 1.07% respectively after isolation of MNCs. The co-expressions of CD271(+)CD133(+) before and after isolation of MNCs were (0.02 +/- 0.01)% and (0.03 +/- 0.02)% respectively. The co-expression of CD133(+) and CD34(+) before and after isolation of MNCs were (0.18 +/- 0.11)% and (0.42 +/- 0.23)% respectively (p < 0.01); meanwhile about 90% of cells with CD133(+) expressed CD34 and 40% of cells with CD34(+) expressed CD133. It is concluded that the established method of detection using flow cytometry with three color fluorescence labelling can be used to detect expression of CD271, CD133 and CD34 in BMCs. The cells with CD271 are different from cells with CD133 and CD34, which suggests that the CD271 may be of important role in evaluating and guiding the clinical application of BM MSCs.

[Chemical forms and ecological effect of soil Mn in liver cancer's high incidence area in Zhu-jiang River Delta, China].

The samples of surface soil, deep soil, and vegetables were collected from the liver cancer's high- and low incidence areas in Zhujiang River Delta to study the relationships between soil Mn forms and vegetables' Mn enrichment. The results showed that the soil Mn in study area was mainly derived from parent materials, and rarely come from human activities. The average soil Mn content in liver cancer's high incidence area was 577.65 mg x kg(-1), being significantly lower than that of liver cancer's low incidence area (718.04 mg x kg(-1)) and whole country (710 mg x kg(-1)). The Mn forms in high incidence area were mainly of residual Mn and Fe-Mn oxide, and less of water soluble Mn and exchangeable Mn, with the sum of the latter two's distribution coefficients being not higher than 4%. In low incidence area, the distribution pattern of soil Mn forms was similar to that in high incidence area, but the absolute contents of the Mn forms were significantly higher. Soil total Mn and soil pH had significant effects on soil Mn forms. There existed significant positive correlations between soil total Mn and the Mn forms of Fe-Mn bound, humic acid bound, carbonate bound, and residual, and negative correlations between soil pH and soil water soluble and organic bound Mn forms. Among the test five kinds of vegetables, Youmai lettuce and Chinese cabbage in liver cancer' s high incidence area had a significantly lower Mn content than in low incidence area, while the other three had less difference. The Mn enrichment in test vegetables was positively correlated with to the content of soil available Mn (sum of water soluble Mn and exchangeable Mn), but had no correlations with the contents of soil total Mn and other Mn forms.

[Preparation and spectra characterization of optically variable pigments with four symmetrical configurations].

The optically variable pigments with four symmetrical configurations were obtained by using the mica titanium as the host materials, which was pretreated in acid and alkaline condition. The reflection differences between the host materials and the coatings were increased by optimizing the number of layers and the arrangement order. The optically variable effect was investigated by X-Rite MA86II five angles spectrophotometer. The impact of symmetrical configurations on improving the color travel effect was studied, and the influence of different coating materials on the hue and the color travel effect was researched. The results show that the reflection rate and the color travel effect of the pigment were improved by coating another material on three symmetrical configurations.

Structure-efficacy relationships of immunostimulatory activity of CpG-containing oligodeoxynucleotides on mouse spleen cells.

AIM: To study the relationship between primary structures of oligodeoxynucleotides (ODN) containing unmethylated deoxycytidyldeoxyguanosine (CpG) dinucleotide motifs and their immunostimulatory activities in mouse spleen cells. METHODS: A series of CpG ODN with different primary structures were synthesized. Their capabilities to stimulate mouse spleen cell proliferation were determined by [3H]thymidine incorporation assay. Cytokine (interleukin [IL]-6, IL-12, and IFN-alpha) secretion spectra induced by CpG ODN were assessed by ELISA. The ability of CpG ODN to activate natural killer cells was evaluated by standard 4 h (51)Cr-release assay. Flow cytometry was utilized to examine the expressions of various lymphocyte surface molecules on diverse immunocytes. An effective CpG ODN for murine, ODN1826, was set as the template of modification and the positive control. RESULTS: The immunostimulatory activities of CpG ODN with different sequences and compositions varied markedly, both in character and in extent. It was useless for improving the immunostimulatory activity of ODN1826 by simply increasing the functional hexameric CpG motif number, modifying the site of CpG motifs, or changing the distance between multi-CpG motifs. However, an addition of a self-complementary palindrome structure at the 3'-end, but not the 5'-end of CpG ODN, aroused marked improvement in its activity. Several designed ODN had superior comprehensive immunostimulatory properties compared to ODN1826. CONCLUSION: The immunostimulatory activity of a CpG ODN was relevant to its primary structure. It was useless for promoting immunostimulatory activity to simply change CpG motif number, space, or distance. The 3'-end palindrome structure of CpG ODN is associated with enhanced immunostimulatory activity.

The relationship between the structure of dermatan sulfate derivatives and their antithrombotic activities.

To study the relationship between the structure of dermatan sulfate (DS) derivatives and their anti-thrombotic activities, DS-derived oligosaccharides (with different structures and relative molecular weight (M(r))) were prepared, and the effects of the DS-derived oligosaccharides on the activities of heparin cofactor II (HCII), activated protein C (APC), blood platelet, and vascular endothelial cells were studied. The major disaccharides of DS and polysulfated dermatan sulfate (PSDS) were IdoA-1-->3-GalNAc-4-OSO(3) and IdoA-2OSO(3)-1-->3-GalNAc4, 6-diOSO(3), respectively. The results showed that the consequence of the thrombotic inhibitory effects of DS and its derivatives were as follows: PSDS>low molecular weight polysulfated dermatan sulfate (LPSDS)>DS. Both DS and PSDS inhibited platelet aggregation in the concentration-dependent manner, and the IC(50) value of DS and PSDS is 12.7+/-1.3 and 28.6+/-0.9 mg/mL, respectively. DS oligosaccharides (DSOSs) and PSDS oligosaccharides (PSDSOSs) both significantly inhibited P-selectin expression on platelet surface (P<0.01), while DSOSs have no different effect compared with PSDSOSs. DSOSs and PSDSOSs significantly enhanced the activity of HCII in inhibiting thrombin in the plasma. The most active PSDSOS was PSDSOS(1) with M(r) of 4959, which enhanced the HCII activity by 91% (P<0.01). The experiments on APC activity showed that DS and its derivatives enhanced APC activity. The most active PSDSOS was PSDSOS(3) with M(r) of 2749, which enhanced the APC activity to 331+/-27% (P<0.01). DSOSs and PSDSOSs enhanced tissue plasminogen activator (t-PA) activity and reduced the plasminogen activator inhibitor (PAI) activity from cultured human umbilical vein endothelial cells (HUVEC), resulting in the ratio of t-PA/PAI going up. PSDSOSs which have the same M(r) as DSOSs produced more active effects in above assays, except for platelet aggregation.

[Study on luminescence properties of Eu2+ in (Sr, Ca)4Si3O8Cl4 host lattice].

Alkali earth chlorosilicate of the type Sr(4-x)Ca(x)Si3O8Cl4 was synthesized through the high temperature solid state method. According to the Van Uitert experimental equation, luminescence properties and crystal-lattice environment of Eu2+ in Sr(4-x) Ca(x)Si3O8Cl4 crystal were discussed. The possibilities of two Eu2+ emission centers, viz. blue and greenish-yellow centers, were found and their corresponding relationships with spectra were also discussed. When the doping amount of calcium(x) varied between 0 and 0.5, Ca2+ ions were embedded in the host lattice of Sr4Si3O8Cl4, and the luminescence of blue center, which was ascribed to the emission of Eu2+ that substituted the octa-coordination Sr2+ sites, dominated and showed blue-green luminescence. Sr(4-x)Ca(x)Si3O8Cl4:yEu2+ exhibited greenish-yellow luminescence when the range of x was between 0.5 and 2. This was due to the fact that the Eu2+ emission originated from the formation of an impurity-trapped exciton state. Greenish-yellow emission center was located in the impurity-trapped exciton state which was the lowest excited state of this system, and the Eu2+ emission was at long wavelengths, and a large Stokes shift was observed.

Effects of dermatan sulfate derivatives on platelet surface P-selectin expression and protein C activity in blood of inflammatory bowel disease patients.

AIM: To investigate the effect of dermatan sulfate (DS) derivatives on platelet surface P-selectin expression and blood activated protein C (APC) activity in patients with inflammatory bowel disease (IBD), and to clarity the anti-inflammatory mechanism of DS derivatives. METHODS: Dermatan sulfate (DS) was sulfated with chlorosulfonic acid to prepare polysulfated dermatan sulfate (PSDS). The major disaccharides of DS and PSDS were determined by 1H nuclear magnetic resonance spectroscopy (1H-NMR) and 13C-NMR. Both DS and PSDS were depolymerized with hydrogen peroxide. The fragments were separated by gel filtration chromatography. The effects of DS derivatives on P-selectin expression were assayed by ELISA method, and blood APC activity was assayed by the synthetic chromogenic substrate method. RESULTS: The major disaccharides of DS and PSDS were IdoA-1-3-GalNAc-4-SO3 and IdoA-2SO3-1-3-GalNAc4, 6-diSO3, respectively. Compared with the adenosine diphosphate stimulated group and IBD control group, DS and its derivatives all had significant inhibitory effects on P-selectin expression (P<0.01), but there was no difference between DS-derived oligosaccharides (DSOSs) and PSDS-derived oligosaccharides (PSDSOSs). The experiments on APC activity showed that DS and its derivatives all enhanced APC activity. The most active DSOS was the one with a relative molecular weight (Mr) of 4,825, which enhanced the APC activity from 106.5+/-11.5% to 181.8+/-22.3% (P<0.01). With the decrease of Mr, the activity of DSOSs decreased gradually. The effect of PSDS on APC activity enhancement was more significant than that of DS, and the APC activity was raised to 205.2+/-22.1% (P<0.01). All the PSDSOSs were more active than DSOSs on the basis of comparable Mr. With the decrease of Mr, the activity of PSDSOSs increased gradually, and the most active PSDSOS was PSDSOS3 with Mr of 2,749, which enhanced the APC activity to 331.2+/-27.8% (P<0.01), then the activity of PSDSOSs decreased gradually. CONCLUSION: DS and its derivatives can significantly inhibit P-selectin expression on platelet surface, but the effect has no correlation with DS molecular mass and sulfation. The effect of DS or its derivatives on APC activity at molecular level involves complex mechanisms that depend on the molecular mass, the degree of sulfation, and the heterogeneous composition of DS. On the same molecular size, the higher the degree of DS sulfation, the more significant the effect on enhancing APC activity.