Increase in CFC-11 emissions from eastern China based on atmospheric observations.

The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons1. The atmospheric concentration of trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s2. A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased3,4. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown3. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.

Comprehensive Evaluation of (+)-Usnic Acid-induced Cardiotoxicity in Rats by Sequential Cross-omics Analysis.

Two-week administration of (+)-usnic acid (UA) induces mitochondrial swelling of cardiomyocytes, and toxicogenomic analysis of the heart revealed upregulation of oxidative stress, amino acid limitation, and endoplasmic reticulum stress-related genes in rats. To analyze the pathogenesis, UA was orally administrated to rats for 1, 4, 7, and 14 days, and sequential histopathological, genomic, and metabolomic analyses were performed on the heart, liver, and plasma. As a result, mitochondrial swelling of cardiomyocytes was observed on day 15 preceded by genomic upregulation on days 5 and 8. Of the focused gene groups, amino acid limitation-related genes represented by Mthfd2 showed numerically higher values or upregulation from day 5, which was sustained through the experimental period. On the contrary, oxidative stress-related genes were upregulated temporally on day 5. In metabolomic analysis, amino acids such as taurocholate and their metabolites fluctuated in concert with the upregulation of amino acid limitation-related genes in the heart, liver, and plasma. Moreover, accumulations of bile acids were manifested in all the tested tissues, while no histopathological change was seen in the liver. Increased bile acids might have an indirect effect on the myocardium; however, more detailed analysis is required. In conclusion, amino acid limitation was suggested as the pivotal toxic trigger of UA-induced cardiotoxicity.

Multiannual top-down estimate of HFC-23 emissions in East Asia.

Trifluoromethane (CHF3, HFC-23), with a 100-year global warming potential (GWP) of 12400, is regulated under the Kyoto Protocol. HFC-23 emissions in East Asia, especially in China, are currently thought to represent the majority of global HFC-23 emissions. This study provides both a bottom-up emission inventory and the multiannual top-down estimate of HFC-23 emissions in East Asia during 2007-2012. The new bottom-up inventory yields improved simulated HFC-23 mixing ratios compared to previous bottom-up inventories. The top-down estimate uses inverse modeling to further improve the model-measurement agreement. Results show that China contributed 94-98% of all HFC-23 emissions in East Asia. Annual a posteriori emissions from China were around 6.3 Gg/yr during the period 2007-2010 after which they increased to 7.1 ± 0.7 Gg/yr in 2011 and 8.8 ± 0.8 Gg/yr in 2012. For the first time, this study also provides a top-down estimate of HFC-23/HCFC-22 (chlorodifluoromethane, CHClF2) coproduction ratios in non-CDM (Clean Development Mechanism) HCFC-22 production plants as well as in all HCFC-22 production plants in China.

Pathogenesis of Kawasaki disease.

Kawasaki disease (KD) most frequently affects infants and young children under 5 years of age. This disease is considered a kind of systemic vasculitis syndrome, and primarily invades the medium-sized muscular arteries, including coronary arteries. Diagnosis of KD is based on characteristic clinical signs and symptoms, which are classified as principal clinical findings and other clinical and laboratory findings. Even though the aetiology of KD is unknown, epidemiological data suggest that some kinds of infectious agents are involved in the onset of KD. In addition, the data indicate that host genetics underlie the disease's pathogenesis. Histologically, coronary arteritis begins 6-8 days after the onset of KD, and leads immediately to inflammation of all layers of the artery. The inflammation spreads completely around the artery; as a result, structural components of the artery undergo intense damage; the artery then begins to dilate. Inflammatory cell infiltration continues until about the 25th day of the disease, after which the inflammatory cells gradually decrease in number. KD arteritis is characterized by granulomatous inflammation that consists of severe accumulation of monocytes/macrophages. Aberrant activation of monocytes/macrophages is thought to be involved in the formation of vascular lesions. The lesions in all the arteries are relatively synchronous as they evolve from acute to chronic injury. There is no fibrinoid necrosis nor any mixture of acute inflammatory lesions and scarring lesions, which are characteristics in polyarteritis nodosa in KD.

Mixed germ cell tumor with embryonal carcinoma, choriocarcinoma, and epithelioid trophoblastic tumor in the ovary of a cynomolgus monkey.

A seven-year-old female cynomolgus monkey had a mass in the left ovary with metastasis to the lung and the right ovary. The mass of these organs showed three different characteristics, and its immunohistochemical profiles were consistent with embryonal carcinoma (EC), choriocarcinoma (CC), and epithelioid trophoblastic tumor (ETT). The EC was characterized with sheets and glandlike structures with large pleomorphic, single-nucleated epithelial cells that were immunohistochemically positive for α-fetoprotein, octamer-4, and CD30, and with multinucleated giant cells resembling syncytiotrophoblasts. The CC also represented biphasic proliferation of the cytotrophoblast positive for cytokeratin 7 (CK7), which showed negative immunoreactivity for all three of the above antibodies, and it was syncytiotrophoblast positive for human chorionic gonadotropin. The ETT showed numerous floating cells in an abundant eosinophilic extracellular matrix with vacuolated or eosinophilic cytoplasm and was immunohistochemically positive for CK7, p63, and α-inhibin, which features nodule or cordlike structures. Collectively, this neoplasm was identified as a mixed germ cell tumor with EC, CC, and ETT. To our knowledge, this is the first report of EC in nonhuman primates as a component of mixed germ cell tumor.

HoxA and HoxB cluster genes subdivide the digestive tract into morphological domains during chick development.

The digestive tract exhibits region-specific morphology and cytodifferentiation along the anteroposterior axis. We analyzed the spatial expression patterns of Hox genes belonging to the HoxA and HoxB cluster (Hoxa-4 approximately a-9, Hoxb-5 approximately b-9) in the developing chick digestive tract. The expression domains of these Hox genes correlated with morphological subdivision of the digestive tract along the anteroposterior axis.

High-level expression of exogenous genes by replication-competent retrovirus vectors with an internal ribosomal entry site.

We report the construction of two types of Rous sarcoma virus (RSV)-based replication-competent avian retrovirus vectors, IR1 and IR2 to express an exogenous gene at a very high level. In these vectors, the internal ribosomal entry site (IRES) derived from encephalomyocarditis virus (EMCV) was inserted between the env gene and an exogenous gene. The IR1 vector retains the splicing acceptor site that is present in the downstream of the env gene while the IR2 vector lacks it. Using a v-fos mutant (v-fos-CD3) as an example of exogenous genes, we show here that both IR1 and IR2 vectors expressed the gene product, CD3, at expression levels 5- and 8-fold higher than that of their parental vector without IRES, respectively. These vectors were moderately stable and kept a high-level expression of CD3 for at least three passages through the cells. Analysis of viral transcripts indicate that exogenous genes carried by both IR vectors were translated exclusively from the IRES that is present in all the species of the viral transcripts. High-level expression of exogenous genes was also observed in the case of the Hoxa-13 gene in the IR1 vector or the fra-2 gene in the IR2 vector, indicating that the extremely high-level expression characteristic of these vectors is applicable to several exogenous genes.

Haplotypes of the 5' region of the IL-4 gene and SNPs in the intergene sequence between the IL-4 and IL-13 genes are associated with atopic asthma.

IL-4 and IL-13 are important in IgE synthesis and allergic inflammation. Therefore, genes encoding IL-4 and IL-13 are candidates for predisposition to asthma and atopy. A recent study in the YAC transgenic mouse has revealed that one of the conserved noncoding sequences (CNS-1) between IL-4 and IL-13 influences the expression of IL-4, IL-5, and IL-13, suggesting that CNS-1 acts as a coordinate regulator of these genes. This investigation screened for mutations in the 13-kb region between IL-4 and IL-13, which includes the human equivalent of the murine CNS-1. Four single nucleotide polymorphisms (SNPs) were found in the region between IL-4 and IL-13 (IL-4-IL-13SNP1, IL-4-IL-13SNP2, IL-4-IL-13SNP3, and IL-4-IL-13SNP4). There was no mutation in the human CNS-1. We genotyped these and other previously reported polymorphisms in IL-4 and IL-13 using asthmatic families, and examined association by transmission disequilibrium test. Two-locus haplotype analysis revealed that haplotypes composed of the IL-4 RP2del, IL-4 +33T, or IL-4 -589T alleles and either IL-4-IL-13SNP3G or IL-4-IL-13SNP4C are transmitted significantly to asthma-affected children (p = 0.002). This data suggests that haplotypes composed of the 5' region polymorphisms in the IL-4 gene and SNPs in the intergene sequence between IL-4 and IL-13 influence the development of asthma.

Histomorphometric characteristics and cellular kinetics of colorectal polyps with epithelial serrated proliferation adjacent to carcinoma.

Four cases of colorectal polyps with epithelial serrated proliferation (CP-ESP) with malignant transformation were studied. In CP-ESP adjacent to carcinoma, if the nuclear size in the surface layer was significantly smaller than those in the bottom and the middle layers of the crypts, the specimen was defined as zone formation positive. If there was no significant difference among the layers, the specimen was defined as zone formation negative. Cell kinetics were evaluated using Ki-67 immunostaining. The CP-ESP regions of cases 1 and 2 showed zone formation with inferior and lateral glandular branching, and were qualitatively hyperplastic on cell kinetics. Cases 3 and 4 showed inferior and lateral glandular branching with no zone formation, and were kinetically neoplastic (adenoma). The histogenesis of hyperplastic polyps with atypia (cases 1 and 2) involves the hyperplastic polyp-carcinoma sequence. In contrast, the development of tubulovillous adenoma or serrated adenoma (cases 3 and 4) may involve the tubulovillous adenoma-carcinoma or serrated adenoma-carcinoma sequence.

Pinonaldehyde and some other organics in rain and snow in central Japan.

Solvent-extractable organic compounds in the rain and snow collected at local cities in the mountainous region in central Japan, were analyzed by GC/MS and GC. Pinonaldehyde (2,2-dimethyl-3-acetyl-cyclobutyl-ethanal), an atmospheric reaction product of alpha-pinene, was detected in the rain and snow for the first time, and n-alkanes (C17-C33), fatty acids (C8-C23), and benzoic acid were also detected as major organic components. Concentrations of pinonaldehyde, C17-C33 n-alkanes, C8-C11 fatty acids, C12-C23 fatty acids and benzoic acid ranged between <0.02-13, 0.10-35, 0.55-5.7, 4.2-19 and <0.02-6.0 microg/l, respectively. Their composition showed some difference in summer and winter. In summer, fatty acids and benzoic acid were more abundant, while pinonaldehyde and n-alkanes were much less. Higher photochemical reactivity and higher bioactivity in summer could explain these seasonal changes except for pinonaldehyde, which would suffer from further oxidation in the atmosphere after its photochemical production from alpha-pinene. Predominance of pinonaldehyde and C12-C23 fatty acids in the rain and snow showed a remarkable contrast to n-alkanes in aerosol phase, which were the most abundant components. It indicated that oxygenated products from biogenic compounds might be important as cloud condensation nuclei in forest areas.

Depth profiles of volatile halogenated hydrocarbons in seawater in the Bay of Bengal.

Measurements were made of bromocarbons (CHBr3 and CH2Br2), iodocarbons (CH2I2 and CH2ClI), and dimethylsulfide (DMS, CH3SCH3) in seawater collected from the Bay of Bengal under tropical stratified conditions. These compounds showed different depth profiles, characteristic of each group. CH2I2 and CH2ClI showed very similar depth profiles to chlorophyll-a, suggesting their production by phytoplankton followed by rapid decay in seawater. The CH2I2 maximum at a depth a little below the CH2ClI maximum was consistent with its more significant photolytic decay. The bromocarbons were less localized in their distributions than were the iodocarbons, suggesting their longer residence time in seawater after their release from phytoplankton. Both of these profiles were different from the pattern of DMS, which had its maxima above the chlorophyll-a maximum layer near the surface.

Identification of Toyocamycin, an agent cytotoxic for multiple myeloma cells, as a potent inhibitor of ER stress-induced XBP1 mRNA splicing.

The IRE1α-XBP1 pathway, a key component of the endoplasmic reticulum (ER) stress response, is considered to be a critical regulator for survival of multiple myeloma (MM) cells. Therefore, the availability of small-molecule inhibitors targeting this pathway would offer a new chemotherapeutic strategy for MM. Here, we screened small-molecule inhibitors of ER stress-induced XBP1 activation, and identified toyocamycin from a culture broth of an Actinomycete strain. Toyocamycin was shown to suppress thapsigargin-, tunicamycin- and 2-deoxyglucose-induced XBP1 mRNA splicing in HeLa cells without affecting activating transcription factor 6 (ATF6) and PKR-like ER kinase (PERK) activation. Furthermore, although toyocamycin was unable to inhibit IRE1α phosphorylation, it prevented IRE1α-induced XBP1 mRNA cleavage in vitro. Thus, toyocamycin is an inhibitor of IRE1α-induced XBP1 mRNA cleavage. Toyocamycin inhibited not only ER stress-induced but also constitutive activation of XBP1 expression in MM lines as well as primary samples from patients. It showed synergistic effects with bortezomib, and induced apoptosis of MM cells including bortezomib-resistant cells at nanomolar levels in a dose-dependent manner. It also inhibited growth of xenografts in an in vivo model of human MM. Taken together, our results suggest toyocamycin as a lead compound for developing anti-MM therapy and XBP1 as an appropriate molecular target for anti-MM therapy.

Factors Affecting the Emission of Monoterpenes from Red Pine (Pinus densiflora).

The mechanism of monoterpene emission from Pinus densiflora was studied using an environmentally controlled gas cabinet. It was found that monoterpene emission rate increases exponentially with temperature and is also influenced by light. These observations were explained reasonably by a mechanism whereby monoterpene emission rate depends on the monoterpene amount in the leaf oil and its saturated vapor pressure.

Homeobox gene expression correlated with the bifurcation process of limb cartilage development.

The complex architecture of the limb cartilage pattern probably develops by the sequential segmentation and branching process of precartilaginous cell condensation under the control of positional signalling provided by the zone of polarizing activity (anteroposterior) and the apical ectodermal ridge (proximodistal). This signalling is monitored and interpreted in the mesenchymal cells and induces the position-specific response of subsets of genes. Homeobox genes may be responsible for the interpretation of signalling. A correlation between limb pattern and expression domains of the homeobox genes in the upstream region of Hox/Chox-4 has been proposed. We have analysed the spatial expression pattern of the Chox-1 genes during development of chick limb buds. In contrast to genes in Hox/Chox-4 expressed coordinately along the anteroposterior axis, homeobox genes in Chox-1 have unique and mutually exclusive expression domains along the proximodistal axis. We report here that the expression domains of the Chox-1 genes are closely related to the segmental structure of cartilage along the proximodistal axis, whereas the expression domains of the Chox-4 genes are related to the cartilage branching pattern.

Coordinated expression of Hoxb genes and signaling molecules during development of the chick respiratory tract.

To elucidate the molecular mechanism for regulating the region-specific morphogenesis of the chicken respiratory tract, we analyzed the spatiotemporal expression patterns of the Hoxb genes, Bmp-2, Bmp-4, Wnt-5a, and Wnt-11 in the developing respiratory tract. We found region-specific expression of these genes in the mesenchymal layer of the respiratory tract. Before bronchial branching proceeds, Hoxb genes show nested expression patterns around the ventral-distal tip of the lung bud. As morphogenesis proceeds, these expression domains correspond to the morphological subdivisions of the chick respiratory tract. Hoxb-5 and Hoxb-6 expression domains demarcate the trachea, bronchial tree, and air sacs. Particularly the expression domains of Hoxb-6 to -9 correspond to the morphological subdivisions of the air sacs along the proximodistal axis. Bmp-4 and Bmp-2 are expressed throughout the entire pulmonary mesenchyme and its dorsal half, respectively. Wnt-5a and Wnt-11 are expressed in the tracheal mesenchyme. Interestingly, the expression domain of Bmp-2 is complementary to the Hoxb-6 domain. The respiratory mesenchyme influences the process of epithelial branching during morphogenesis. By tissue recombination experiments, we found that the dorsal and the ventral pulmonary mesenchyme, demarcated by Hoxb-6 expression, have different inductive capacities toward the tracheal epithelium. These observations suggest the possibility that Hoxb genes are involved in the system specifying regional differences in morphogenesis and cytodifferentiation of respiratory tract. In addition, it is possible that BMPs and WNTs mediate region-specific epithelial-mesenchymal interaction in this system.

Coordinated expression of Abd-B subfamily genes of the HoxA cluster in the developing digestive tract of chick embryo.

To elucidate the molecular mechanism for determining the positional specificity and morphogenesis of the chicken digestive tract, we analyzed expression patterns of Hox genes during development of the digestive tract, focusing on the Abd-B subfamily genes of the HoxA cluster, Hoxa-9,-10,-11, and -13. Region-specific expression of these genes was found in the visceral mesoderm. In early development, before commencement of hindgut closure, they were expressed in a Russian doll pattern with the more 5' located gene on the cluster showing the more posterior restricted expression domain. At middle stage, when hindgut closure had occurred and morphological subdivision of the hindgut was gradually becoming distinct, the expression domains of each gene became mutually exclusive and restricted to the subdivisions; i.e., Hoxa-9 in the posterior part of the small intestine and the ceca, Hoxa-10 in the ceca, Hoxa-11 in the ceca, the large intestine, and the cloaca, and Hoxa-13 in the cloaca. At later stages, when the bilateral branches of the ceca had formed, the overlapping expression domains of Hoxa-10 and -11 were strongly correlated with the budding processes of the ceca. These observations suggest the possibility that Hox genes are responsible for determination of the position-specific differentiation of the visceral mesoderm of the digestive system and regulate the budding processes of the ceca.

Gas chromatographic-mass spectrometric analysis of formaldehyde in ambient air using a sampling tube.

A gas chromatographic-mass spectrometric technique for the analysis of trace concentrations of formaldehyde in air is described. Molecular Sieve 13X was found to be an excellent adsorbent. The collected samples were thermally desorbed onto the analytical column (Porapak T) for separation, and quantified by mass fragmentography (m/e 29 and 30). Advantages of the technique include ppb sensitivity, selectivity and quantitative recovery. Experimental results are given for air samples in a rural area.

Chicken homeobox gene Msx-1: structure, expression in limb buds and effect of retinoic acid.

A chicken gene carrying a homeobox highly homologous to the Drosophila muscle segment homeobox (msh) gene was isolated and designated as Msx-1. Conceptual translation from the longest ORF gave a protein of 259 amino acids lacking the conserved hexapeptide. Northern analysis detected a single 2.6 kb transcript. As early as day 2 of incubation, the transcript was detected but was not found in adult tissue. In situ hybridization analysis revealed that Msx-1 expression is closely related to a particular mesenchymal cell lineage during limb bud formation. In early stage embryos, Msx-1 was expressed in the somatopleure. When primordial mesenchyme cells for limb bud were generated from the Wolffian ridge of the somatopleure, Msx-1 expression began to diminish in the posterior half of the limb bud then in the presumptive cartilage-forming mesenchyme. In developing limb buds, remarkable expression was seen in the apical ectodermal ridge (AER), which is responsible for the sustained outgrowth and development of the limb. The Msx-1 transcripts were found in the limb mesenchymal cells in the region covering the necrotic zone and ectodermal cells overlying such mesenchymal cells. Both ectodermal and mesenchymal expression in limb bud were rapidly suppressed by local treatment of retinoic acid which can generate mirror-image duplication of digits. This indicates that retinoic acid alters the marginal presumptive non-cartilage forming mesenchyme cell lineage through suppression of Msx-1 expression.

Retinoic acid changes the proximodistal developmental competence and affinity of distal cells in the developing chick limb bud.

In the developing chick limb bud, retinoic acid (RA) has a striking effect on anteroposterior axis formation, resulting in a duplicated pattern of digits. There is no evidence, however, that RA affects proximodistal axis formation in the developing chick limb bud, although RA induces proximodistal duplication in regenerating amphibian limbs. We describe a series of investigations on the effect of RA on the proximodistal axis in the chick limb bud. A RA-containing bead applied to the anterior margin of the chick limb bud at stage 20 induces the anteroposterior duplication of autopodial structures at the wrist level. We found that the RA-treated tissue has the ability to form more proximal structures. When a tissue graft from the RA-treated anterior region was implanted into a stage 17 wing bud (in which the stylopod is developing in the progress zone), the graft produced a humerus, radius-ulna, and digits. When the graft was implanted into a stage 19 wing bud (in which the zeugopod is developing in the progress zone), a zeugopod and digits were formed. These results were associated with changes in the expression of Hox-A genes in the RA-treated grafts, whose domains were reorganized to be similar to those in host tissues 24 h after grafting. When a small graft of RA-treated tissue was implanted into the apex of a stage 19 wing bud, the cells were found in the zeugopod and autopod, whereas cells of control fragments were found only in the autopod region. In vitro, distal cells from different stage limb buds are known to segregate from each other. However, RA-treated stage 24 distal cells did not sort out from stage 20 distal cells and mixed homogeneously. These results suggest that RA induces distal cells to adopt "younger" properties which render them susceptible to forming more proximal patterns under the direction of host signals. The effects of RA on proximodistal patterns in developing chick limb buds appear to differ from its effects on proximodistal patterns in regenerating urodele limbs because RA can induce the proximodistal duplication in situ in the regenerating limbs.