Regional characteristics of sulfur and lead isotope ratios in the atmosphere at several Chinese urban sites

Sulfur and lead isotope ratios in the atmosphere were measured at several selected sites (Harbin, Changchun, Dalian, Waliguan, Shanghai, Nanjing, Guiyang) in China and Tsukuba (Japan), to reveal regional sources characteristics over Eastern Asia. Average S isotope ratios for SO2 and sulfate in the atmosphere in China were close to those of the coals used in each region, indicating a considerable contribution of coal combustion to the sulfur compounds in the atmosphere. Most northern cities had around 5% sulfur isotope ratio, while Guiyang, a southwestern city in China, showed a considerably lower sulfur isotope ratio (about -3%) because of the unusually light sulfur isotope ratio of coals in this region. These were considerably different from the value (-1.4%) for Tsukuba (Japan). Lead isotope ratios also suggested that coal combustion considerably contributed to atmospheric lead in some cases in China. At the same time, influences by the emission of Chinese lead ores were also observed in northern cities. Seasonal variations of both sulfur and lead isotope ratios indicated the existence of a certain amount of industrial sources other than coal combustion. In addition, fractionation effect between SO2 and sulfate showed a seasonal tendency (high in winter (0-6%) and low in summer (-1-3%)), suggesting the oxidation pathway of SO2 changed seasonally.

Vascular mechanisms of cyclosporin-induced hypertension in the rat

Numerous studies have explored the pathogenesis of cyclosporin A (CysA)-induced hypertension; however, none has assessed the impact of CysA treatment on resistance arteries in the setting of elevated blood pressure. Therefore, we studied the chronic effect of CysA on rat mesenteric artery resistance vessels (ex vivo). CysA (25 mg/kg per d for 7 d), but not vehicle, significantly raised systolic blood pressure (13.4 +/- 2.2 mmHg, P < 0.003, n = 9 per group). The resistance vessels from CysA-treated rats showed a small but significant decrease in norepinephrine sensitivity (P < 0.03) and a pronounced decrease in endothelium-dependent and -independent relaxation (P < 0.001) compared to controls. Endothelin-1 sensitivity tended to be diminished (P = 0.07). The direct (in vitro) effect of CysA was subsequently evaluated in resistance vessels from nontreated animals (n = 8) and exposed to CysA (2 micrograms/ml) for 24 h. As observed in vivo, CysA significantly decreased endothelium-dependent and -independent relaxations (P < 0.05) and attenuated norepinephrine sensitivity (P = 0.06). Methylene blue, a nitric oxide quencher, significantly inhibited the acetylcholine-induced relaxation in control, but not in CysA vessels, suggesting a selective action of CysA on the nitric oxide pathway. We conclude that CysA-induced hypertension is the consequence of a primary effect on resistance vessel relaxation, not increased vasoconstriction, as previously suggested.

Sequence profiles of immunoglobulin and immunoglobulin-like domains

Immunoglobulins (Ig) are highly modular proteins, consisting of variable and constant domains, which have clear, conserved sequence patterns. These sequence patterns have allowed T-cell receptor (TCR) and major histocompatibility complex (MHC) molecule domains, as well as some cell adhesion, cell surface receptor and muscle protein domains, to be identified as forming a superfamily of related proteins together with the Ig-domains. The domains of these proteins have been grouped into four sets: variable (V-set), constant-1 (C1-set), constant-2 (C2-set) and intermediate (I-set). X-ray and NMR studies have shown that these domains form a Greek-key beta-sandwich structure with the sets differing in the number of strands in the beta-sheets as well as in their sequence patterns. The conserved sequence elements in the major sets of Ig and Ig-like molecules have previously been reported as general sequence profiles. This work examines the variability within these sets. Detailed sequence profiles and consensus sequences for these sets and groups have been constructed and a novel form of presentation has been developed to overcome some of the drawbacks of current methods of presenting consensus sequences. The profiles that were constructed allow a comparison of the similarities and differences among the sets of Ig and Ig-like sequences and provide a means by which sequences can be tested for compatibility with Ig-like sequence motifs. As well, the sequence separations of the main residues in the characteristic "pin" structure of Ig-like molecules were examined for variation among the groups. From the profiles constructed here, measures of the degree of conservation within the groups of molecules were determined. These measures were used to assist in a reconsideration of possible evolutionary pathways between the major structural groups of the Ig-superfamily.

Induction of contraction in isolated rat aorta by cyclosporine

Cyclosporine (CsA) is a new immunosuppressive agent that has adverse effects of nephrotoxicity and de novo appearance of hypertension. It has been hypothesized that the mechanism of the contrary effects is through an action of CsA on vascular smooth muscle. To test this hypothesis, thoracic aortas were isolated from Wistar Kyoto rats and ring segments prepared for measurement of tension. CsA (5 X 10(-6) M) induced a slow increase in tone of the isolated rings with a response at 3 hr of 0.70 +/- 0.17 N/m2 X 10(4). This contraction was significantly inhibited by the Ca2+ channel blocker verapamil (0.30 +/- 0.08 N/m2 X 10(4) after 3 hr, P less than 0.05) and by the noncompetitive alpha-antagonist phenoxybenzamine (0.06 +/- 0.07 N/m2 X 10(4) after 3 hr, P less than 0.05). The competitive alpha-antagonist phentolamine had mixed effects. CsA does not irreversibly alter vascular smooth muscle contractile ability since a 3 hr exposure to the agent had no effect on either the maximal contractile response or sensitivity to KCl. We conclude that CsA can directly induce contraction in vascular smooth muscle, perhaps by inducing a release of norepinephrine from adrenergic nerve terminals. The data are consistent with the hypothesis that CsA induces nephrotoxicity and de novo hypertension through a contractile effect on vascular smooth muscle.

Forty-year experience with second malignancies after treatment of childhood cancer: analysis of outcome following the development of the second malignancy

As the cure rate for childhood malignancies increases, the number of patients at risk for development of second malignancies also increases. Due to the potentially long remaining life span, long-term follow-up is difficult and patients are often at risk after presumptive cures. Some authors believe that cure rates for second malignancies are similar to cure rates for primary malignancies. We reviewed the records of 162 patients seen at our institution who had developed a second malignancy after treatment for childhood cancer. Presentation, age at diagnosis, tumor histology, extent of tumor, treatment (including radiotherapy with dosage when available, and chemotherapy) plus outcome were recorded. Mean age at diagnosis of the primary malignancy was 10.3 years. The most common primary malignancy was Hodgkin's disease (33) followed by soft tissue sarcoma (28), retinoblastoma (20), bone tumor (17), central nervous system (CNS) tumor (13), leukemia (8), Wilms' tumor (7), non-Hodgkin's lymphoma (6), neuroblastoma (5), thyroid neoplasm (5), and others (20). The average interval between diagnosis of the first and second malignancy was 10.8 years. These second tumors carried a high mortality. Only 56 patients have no evidence of disease. Five patients are known to be alive with disease and 92 patients have expired due to their second malignancy. Disease status in 8 patients is unknown. The most common second malignancy was osteosarcoma (35) followed by soft tissue sarcoma (24), breast cancer (15), leukemia (14), thyroid carcinoma (14), CNS tumors (12), melanoma (8), nonmelanomatous skin cancer (8), lymphoma (5), and others (27).(ABSTRACT TRUNCATED AT 250 WORDS)

Elevated interleukin-6 expression in keloid fibroblasts

Keloids are characterized by a net accumulation of collagen. To date, the role of growth factors and various cytokines in the pathogenesis of these lesions has not been fully characterized. Interleukin-6 (IL-6) is an important immunoregulatory cytokine that has been implicated in a number of fibrotic autoimmune diseases such as scleroderma, interstitial nephritis, and pulmonary interstitial fibrosis. However, the role of IL-6 in the development of keloids has yet to be defined. This study demonstrates increased expression of the IL-6 gene in fibroblasts isolated from patients with keloids when compared with control fibroblasts using the ribonuclease protection assay. Subsequent detection of increased levels of IL-6 secretion by keloid fibroblasts is also demonstrated under unstimulated and stimulated conditions using serum and interferon gamma (IFN-gamma) (unstimulated: 0.3694 + 0.2499 pg/cell vs 0.0662 + 0.0786 pg/cell, P = 0.0137; serum: 1.066 + 0.513 pg/cell vs 0.233 + 0.231 pg/cell, P = 0.0027; serum and IFN-gamma: 1.286 + 0.395 pg/cell vs 0.244 + 0.199 pg/cell, P < 0.0001). These results suggest that IL-6 may play a significant role in the pathogenesis of keloids.

Inhibition of cellular transformation by berry extracts

Recent studies have examined and demonstrated the potential cancer chemopreventive activity of freeze-dried berries including strawberries and black raspberries. Although ellagic acid, an abundant component in these berries, has been shown to inhibit carcinogenesis both in vivo and in vitro, several studies have reported that other compounds in the berries may also contribute to the observed inhibitory effect. In the present study, freeze-dried strawberries (Fragara ananassa, FA) or black raspberries (Rubus ursinus, RU) were extracted, partitioned and chromatographed into several fractions (FA-F001, FA-F003, FA-F004, FA-F005, FA-DM, FA-ME from strawberries and RU-F001, RU-F003, RU-F004, RU-F005, RU-DM, RU-ME from black raspberries). These extracts, along with ellagic acid, were analyzed for anti-transformation activity in the Syrian hamster embryo (SHE) cell transformation model. None of the extracts nor ellagic acid by themselves produced an increase in morphological transformation. For assessment of chemopreventive activity, SHE cells were treated with each agent and benzo[a]pyrene (B[a]P) for 7 days. Ellagic acid, FA-ME and RU-ME fractions produced a dose-dependent decrease in transformation compared with B[a]P treatment only, while other fractions failed to induce a significant decrease. Ellagic acid, FA-ME and RU-ME were further examined using a 24 h co-treatment with B[a]P or a 6 day treatment following 24 h with B[a]P. Ellagic acid showed inhibitory ability in both protocols. FA-ME and RU-ME significantly reduced B[a]P-induced transformation only when co-treated with B[a]P for 24 h. These results suggest that a methanol extract from strawberries and black raspberries may display chemopreventive activity. The possible mechanism by which these methanol fractions (FA-ME, RU-ME) inhibited cell transformation appear to involve interference of uptake, activation, detoxification of B[a]P and/or intervention of DNA binding and DNA repair.

Applications of geographic information systems (GIS) data and methods in obesity-related research

Geographic information systems (GIS) data/methods offer good promise for public health programs including obesity-related research. This study systematically examined their applications and identified gaps and limitations in current obesity-related research. A systematic search of PubMed for studies published before 20 May 2016, utilizing synonyms for GIS in combination with synonyms for obesity as search terms, identified 121 studies that met our inclusion criteria. We found primary applications of GIS data/methods in obesity-related research included (i) visualization of spatial distribution of obesity and obesity-related phenomena, and basic obesogenic environmental features, and (ii) construction of advanced obesogenic environmental indicators. We found high spatial heterogeneity in obesity prevalence/risk and obesogenic environmental factors. Also, study design and characteristics varied considerably across studies because of lack of established guidance and protocols in the field, which may also have contributed to the mixed findings about environmental impacts on obesity. Existing findings regarding built environment are more robust than those regarding food environment. Applications of GIS data/methods in obesity research are still limited, and related research faces many challenges. More and better GIS data and more friendly analysis methods are needed to expand future GIS applications in obesity-related research.

Vitamin D and gestational diabetes mellitus: a systematic review based on data free of Hawthorne effect

BACKGROUND

Gestational diabetes mellitus (GDM) is an increasingly prevalent disorder, associated with low blood vitamin D level.

OBJECTIVES

To evaluate the relationship between vitamin D and GDM.

SEARCH STRATEGY

EMBASE, MEDLINE, Cochrane Library and China Biology Medicine disc were searched up to May 2017. The references of previous studies were screened.

SELECTION CRITERIA

Observational studies on the relationship between vitamin D and GDM free from Hawthorne effect and randomised controlled trials of vitamin D supplementation during pregnancy for preventing or treating GDM were included.

DATA COLLECTION AND ANALYSIS

Data and information of included articles were extracted by duplicate using piloted tables. Newcastle-Ottawa Scale and Cochrane Handbook were used for quality assessment. Random-effects models were used for meta-analyses. Heterogeneity tests, sensitivity analysis and analysis of publication bias were conducted.

MAIN RESULTS

Eighty-seven observational studies and 25 randomised controlled trials involving 55 859 and 2445 women, respectively, were included. Low blood vitamin D level during pregnancy was associated with a higher risk of GDM (OR 1.850, 95% CI 1.471-2.328). Blood vitamin D level for women with GDM were lower than in the control women. Blood vitamin D level was associated with fasting plasma glucose (FPG) and homeostasis model of assessment for insulin resistance index (HOMA-IR) (r = -0.100 and r = -0.351), whereas the correlation between blood vitamin D level and fasting insulin (FINS) might be concealed by publication bias. Vitamin D intervention during pregnancy could change the blood levels of vitamin D, FINS, FPG, HOMA-IR, glutathione, C-reactive protein and lipid.

CONCLUSIONS

Low blood vitamin D level could increase the risk of GDM, and vitamin D supplementation during pregnancy could ameliorate the condition of GDM.

TWEETABLE ABSTRACT

Low blood vitamin D increases gestational diabetes mellitus (GDM) risk. Vitamin D supplementation ameliorates GDM condition.

An abundant DNA binding protein from the hyperthermophilic archaeon Sulfolobus shibatae affects DNA supercoiling in a temperature-dependent fashion

The DNA binding protein Ssh10b, a member of the Sac10b family, has been purified from the hyperthermophilic archaeon Sulfolobus shibatae. Ssh10b constitutes about 4% of the cellular protein. Electrophoretic mobility shift assays showed that Ssh10b first bound a double-stranded DNA fragment with an estimated binding size of approximately approximately 12 bp, forming distinct shifts, until the DNA was coated with the protein. Binding of more Ssh10b resulted in the formation of smears of lower mobilities. The migration pattern of the smearing Ssh10b-DNA complexes was affected by temperature, whereas that of complexes associated with the distinct shifts was not. Interestingly, Ssh10b was capable of constraining negative DNA supercoils in a temperature-dependent fashion. While the ability of the protein to constrain supercoils was weak at 25 degrees C, it was enhanced substantially at 45 degrees C or higher temperatures (up to 80 degrees C). Taken together, our data suggest that archaeal proteins of the Sac10b family may affect the topology of chromosomal DNA in thermophilic archaea at their growth temperatures.

Association of SNPs and haplotypes in GABAA receptor beta2 gene with schizophrenia

Disturbances in GABAergic system have been observed in schizophrenics. In the present study, population association analysis was performed on 19 SNPs in the alpha(1), beta(2), gamma(2), epsilon and pi subunit genes of GABA(A) receptor. Five SNPs in GABRB2, namely B2I7G1584T, rs1816071, rs194072, rs252944 and rs187269, were found to be significantly associated, and their haplotypes in linkage disequilibrium, with schizophrenia. This represents the first report on any disease association of SNPs in the human GABA(A) receptor genes, and focuses attention on the GABAergic hypothesis of schizophrenia etiology.

Alteration of dopaminergic markers in gastrointestinal tract of different rodent models of Parkinson's disease

Parkinson's disease (PD) is a progressive neurological disorder that is often associated with various gastrointestinal (GI) symptoms. The link between the alteration of dopaminergic system and the symptoms of the GI tract in PD is complicated. To determine the changes in the dopaminergic system in the GI tract in PD, two kinds of rodent PD models were used in the present study. One was 6-hydroxydopamine (6-OHDA) -treated rats in which 6-OHDA was microinjected in the bilateral substantia nigra (SN). The other was 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) -treated mice in which MPTP was injected intraperitoneally. Immunofluorescence, reverse transcription (RT)-real time polymerase chain reaction (PCR) and Western blot were used to evaluate and compare the levels of mRNA and protein expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the GI tract between normal and rodent PD models, as well as between 6-OHDA-treated rats and MPTP-treated mice. The results indicated that TH- and DAT-positive cells were widely distributed in the GI tract. There were significant differences in TH and DAT expression in the GI tract between normal and PD models, as well as between 6-OHDA-treated rats and MPTP-treated mice. The protein levels of TH and DAT in the GI tract were significantly increased in 6-OHDA-treated rats, but the protein level of TH was significantly decreased in MPTP-treated mice. In addition, there was visible atrophy of gastric epithelial parietal cells in MPTP-treated mice, although the protein level of DAT was not significantly changed. The different alterations of dopaminergic system in the GI tract of the two kinds of PD models might underline the differences in GI symptoms in PD patients and might be correlated with the disease severity and disease process affecting the GI tract.

Farnesol inhibits L-type Ca2+ channels in vascular smooth muscle cells

Earlier experiments with animal and human arteries have shown that farnesol, a natural 15-carbon (C15) isoprenoid, is an inhibitor of vasoconstriction (Roullet, J.-B., Xue, H., Chapman, J., McDougal, P., Roullet, C. M., and McCarron, D. A. (1996) J. Clin. Invest. 97, 2384-2390). We report here that farnesol reduced KCl- and norepinephrine-dependent cytosolic Ca2+ transients in fura-2-loaded intact arteries. An effect on Ca2+ signaling was also observed in cultured aortic smooth muscle cells (A10 cells). In these cells, farnesol reduced KCl-induced [Ca2+]i transients and mimicked the inhibitory effect of Ca2+-free medium on the [Ca2+]i response to both 12,13-phorbol myristate acetate, a protein kinase C activator, and thapsigargin, a specific endoplasmic reticulum ATPase inhibitor. Perforated patch-clamp experiments further showed in two vascular smooth muscle cell lines (A10 and A7r5), a reversible, dose-dependent inhibitory effect of farnesol on L-type Ca2+ currents (IC50 = 2.2 microM). Shorter (C10, geraniol) and longer (C20, geranylgeraniol) isoprenols were inactive. L-type Ca2+ channel blockade also occurred under tight (gigaohm) seal configuration using cell-attached, single-channel analysis, thus suggesting a possible action of farnesol from within the intracellular space. We finally demonstrated that farnesol did not affect Ca2+-sensitive pathways implicated in smooth muscle contraction, as tested with alpha-toxin permeabilized arteries. Altogether, our results indicate that farnesol is an inhibitor of vascular smooth muscle Ca2+ signaling with plasma membrane Ca2+ channel blocker properties. The data have implications for the endogenous and pharmacological regulation of vascular tone by farnesol or farnesol analogues.

3D-QSAR model of flavonoids binding at benzodiazepine site in GABAA receptors

With flavone as a structural template, three-dimensional quantitative structure-activity relationship (3D-QSAR) studies and ab initio calculations were performed on a series of flavonoids. A reasonable pharmacophore model was built through CoMFA, CoMSIA, and HQSAR analyses and electrostatic potential calculations. A plausible binding mode for flavonoids with GABA(A) receptors was rationalized. On the basis of the commonly recognized binding site, the specific S1 and S2 subsites relating to substituent positions were proposed. The different binding affinities could be explained according to the frontier orbitals and electrostatic potential (ESP) maps. The ESP could be used as a novel starting point for designing more selective BZ-binding-site ligands.

Role of the alpha(v)beta6 integrin in human oral squamous cell carcinoma growth in vivo and in vitro

Expression of the alpha(v)beta6 integrin is strikingly upregulated in several types of carcinoma, including human oral squamous cell carcinoma (SCC). Employing a neutralizing monoclonal antibody to alpha(v)beta6, we investigated its role in cell adhesion, proliferation, migration, and in vivo growth of an invasive human SCC line, termed HSC-3. We found that alpha(v)beta6 is strictly required for HSC-3 cell growth in a three-dimensional collagen gel and also prominently contributes to cell migration in two different assay systems. In addition, the anti-alpha(v)beta6 antibody inhibited the invasive growth of HSC-3 cells transorally injected into nude mice. In the presence of the coinjected antibody, the average tumor size at 10 days was reduced by 59%. Histologically, antibody-treated tumors appeared less invasive than control tumors. Furthermore, intravenous application of a neutralizing antibody to the alpha(v) integrin subunit retarded HSC-3 tumor growth. These results point to a possible critical role of the alpha(v)beta6 integrin in controlling growth and invasion of human oral cancer cells.

Prediction of programmed-temperature retention values of naphthas by wavelet neural networks

The wavelet neural network (WNN) was used to predict the programmed-temperature retention values of naphthas. In WNN, a Morlet mother wavelet was used as a transfer function, and the convergence speed was faster than other neural networks. Sixty-four compounds (selected randomly from 94) were used as a training set, and the 30 remaining compounds were used as a test set. A very satisfactory result was obtained only after about 8000 training epochs. The other two methods, the artificial neural network (ANN) and the Simpson integral method, were also used for this study. The comparison of results obtained from three methods showed that the WNN is the most suitable tool in predicting programmed-temperature retention values of naphthas, consequently this method can be used to provide reliable data for the petrochemical industry.

Local Structure and Short-Range Order in a NiCoCr Solid Solution Alloy

Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.

Interaction of flavones from the roots of Scutellaria baicalensis with the benzodiazepine site

A radioreceptor binding assay was used to guide the isolation of four chemical constituents in the organic solvent extracts of Scutellaria baicalensis Georgi capable of binding to the benzodiazepine site (BZD-S) of the GABAA receptor: wogonin (Ki = 2.03 +/- 0.24 microM), baicalin (Ki = 77.10 +/- 4.79 microM), baicalein (Ki = 5.69 +/- 0.95 microM), and scutellarein (Ki = 12.00 +/- 1.27 microM). All four compounds contain the flavonoid phenylbenzopyrone nucleus. Based on BZD-S binding, the order of affinity among these four compounds was wogonin > baicalein > scutellarein > baicalin.

First case of hepatopancreatic necrosis disease in pond-reared Chinese mitten crab, Eriocheir sinensis, associated with microsporidian

An epidemic of hepatopancreatic necrosis disease (HPND) with a high mortality rate (40%-50%) recently occurred in the cultured Chinese mitten crab, Eriocheir sinensis, which is a very important economic crustacean species in China. Histology revealed infection by a microsporidian parasite within the cytoplasm of the epithelial cells of the hepatopancreas. Numerous discrete inclusions in the infected cells and presumably free parasite spores were also observed. By negative staining using electron microscopy, a typical morphology of spores was observed with a protuberant front of the anchoring disc. Infection was confined to the epithelial cells of the hepatopancreas, with no other organ implicated. By sequencing the PCR products using specific primers based on conserved regions of microsporidian small subunit (18S) ribosomal DNA, it was revealed that the parasite from HPND ponds had 99% sequence identity to that of Hepatospora eriocheir. Phylogentic analysis also placed the microsporidian in the same lineage as H. eriocheir. This study reported the first case of widespread infections of H. eriocheir associated with HPND found in the pond-reared Chinese mitten crab, E. sinensis. The description of microsporidian in this important commercial host is fundamental for future consideration of factors affecting stock health and sustainability.

Imprinting in the schizophrenia candidate gene GABRB2 encoding GABA(A) receptor β(2) subunit

Schizophrenia is a complex genetic disorder, the inheritance pattern of which is likely complicated by epigenetic factors yet to be elucidated. In this study, transmission disequilibrium tests with family trios yielded significant differences between paternal and maternal transmissions of the disease-associated single-nucleotide polymorphism (SNP) rs6556547 and its haplotypes. The minor allele (T) of rs6556547 was paternally undertransmitted to male schizophrenic offsprings, and this parent-of-origin effect strongly suggested that GABRB2 is imprinted. 'Flipping' of allelic expression in heterozygotes of SNP rs2229944 (C/T) in GABRB2 or rs2290732 (G/A) in the neighboring GABRA1 was compatible with imprinting effects on gene expression. Clustering analysis of GABRB2 mRNA expressions suggested that imprinting brought about the observed two-tiered distribution of expression levels in controls with heterozygous genotype at the disease-associated SNP rs1816071 (A/G). The deficit of upper-tiered expressions accounted for the lowered expression levels in the schizophrenic heterozygotes. The occurrence of a two-tiered distribution furnished support for imprinting, and also pointed to the necessity of differentiating between two kinds of heterozygotes of different parental origins in disease association studies on GABRB2. Bisulfite sequencing revealed hypermethylation in the neighborhood of SNP rs1816071, and methylation differences between controls and schizophrenia patients. Notably, the two schizophrenia-associated SNPs rs6556547 and rs1816071 overlapped with a CpG dinucleotide, thereby opening the possibility that CpG methylation status of these sites could have an impact on the risk of schizophrenia. Thus multiple lines of evidence pointed to the occurrence of imprinting in the GABRB2 gene and its possible role in the development of schizophrenia.

LepR-Expressing Stem Cells Are Essential for Alveolar Bone Regeneration

Stem cells play a critical role in bone regeneration. Multiple populations of skeletal stem cells have been identified in long bone, while their identity and functions in alveolar bone remain unclear. Here, we identified a quiescent leptin receptor–expressing (LepR+) cell population that contributed to intramembranous bone formation. Interestingly, these LepR+ cells became activated in response to tooth extraction and generated the majority of the newly formed bone in extraction sockets. In addition, genetic ablation of LepR+ cells attenuated extraction socket healing. The parabiosis experiments revealed that the LepR+ cells in the healing sockets were derived from resident tissue rather than peripheral blood circulation. Further studies on the mechanism suggested that these LepR+ cells were responsive to parathyroid hormone/parathyroid hormone 1 receptor (PTH/PTH1R) signaling. Collectively, we demonstrate that LepR+ cells, a postnatal skeletal stem cell population, are essential for alveolar bone regeneration of extraction sockets.

Alteration of dopaminergic markers in gastrointestinal tract of different rodent models of Parkinson's disease

Parkinson's disease (PD) is a progressive neurological disorder that is often associated with various gastrointestinal (GI) symptoms. The link between the alteration of dopaminergic system and the symptoms of the GI tract in PD is complicated. To determine the changes in the dopaminergic system in the GI tract in PD, two kinds of rodent PD models were used in the present study. One was 6-hydroxydopamine (6-OHDA) -treated rats in which 6-OHDA was microinjected in the bilateral substantia nigra (SN). The other was 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) -treated mice in which MPTP was injected intraperitoneally. Immunofluorescence, reverse transcription (RT)-real time polymerase chain reaction (PCR) and Western blot were used to evaluate and compare the levels of mRNA and protein expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the GI tract between normal and rodent PD models, as well as between 6-OHDA-treated rats and MPTP-treated mice. The results indicated that TH- and DAT-positive cells were widely distributed in the GI tract. There were significant differences in TH and DAT expression in the GI tract between normal and PD models, as well as between 6-OHDA-treated rats and MPTP-treated mice. The protein levels of TH and DAT in the GI tract were significantly increased in 6-OHDA-treated rats, but the protein level of TH was significantly decreased in MPTP-treated mice. In addition, there was visible atrophy of gastric epithelial parietal cells in MPTP-treated mice, although the protein level of DAT was not significantly changed. The different alterations of dopaminergic system in the GI tract of the two kinds of PD models might underline the differences in GI symptoms in PD patients and might be correlated with the disease severity and disease process affecting the GI tract.

Genetic effect of two polymorphisms in the apolipoprotein A5 gene and apolipoprotein C3 gene on serum lipids and lipoproteins levels in a Chinese population

Two polymorphisms, apolipoprotein A5 (APOA5) -1131T>C and apolipoprotein C3 (APOC3) -482C>T, were examined in a healthy Chinese group. Analysis of covariance (ancova) showed that both -1131T>C and -482C>T minor alleles were associated with triglyceride (TG)-raising effects (p < 0.001 and p = 0.012, respectively) after adjustment of sex, age, and body mass index (BMI). Moreover, -1131T>C minor alleles were also found to be associated with total cholesterol (TC)-raising effects (p = 0.045). However, the relationship between -482C>T minor alleles and TC-raising effects was not observed after adjustment of sex, age, and BMI. By contrast, significant inverse associations were noted between minor alleles (-1131T>C and -482C>T) and high-density lipoprotein cholesterol (HDL-C) concentrations (p = 0.021 and p = 0.021, respectively). Linear regression analysis showed that the effects of -1131T>C and -482C>T polymorphisms on TG and HDL-C (0.001 and 0.008; 0.041 and 0.005, respectively) are independent and additive and that -1131T>C can seriously affect the levels of TG (0.001 vs 0.008). The additive effect of the two polymorphisms was confirmed further by haplotype analysis. Our results strongly support that the two single nucleotide polymorphisms, -1131T>C in APOA5 and -482C>T in APOC3, are related to the levels of serum TG and HDL-C and those of other several lipids and lipoproteins in the Chinese population.