Japanese species of Alternaria and their species boundaries based on host range

To clarify the diversity of plant-parasitic Alternaria species in Japan, diseased samples were collected, and fungal isolates established in culture. We examined 85 isolates representing 23 species distributed in 14 known sections based on conidial morphology and DNA phylogeny. Three species were found to be new, A. cylindrica, A. paragomphrenae and A. triangularis. Furthermore, a lectotype was designated for A. gomphrenae, and epitypes for A. cinerariae, A. gomphrenae, A. iridicola, and A. japonica. Species boundaries of isolates were also clarified by studying phenotypes and determining host ranges. Alternaria gomphrenae and related species in sect. Alternantherae were recognized as distinct species owing to their host specificity. Among the species infecting Apiaceae, the pathogenicity of A. cumini and a novel species, A. triangularis ex Bupleurum, were confirmed as host specific. Another novel species, A. cylindrica, proved to be host specific to Petunia. Alternaria iridicola was recognized as a large-spored species in sect. Alternaria, being host specific to Iris spp. On the other hand, the experimental host ranges of three morphologically and phylogenetically distinct species infecting Brassicaceae (A. brassicae, A. brassicicola, and A. japonica) showed almost no differences. Alternaria brassicicola and A. porri were even found on non-host plants. In general, host ranges of Alternaria species correlated with morphology and molecular phylogeny, and combining these datasets resulted in clearer species boundaries.

Marine radioecology after the Fukushima Dai-ichi nuclear accident: Are we better positioned to understand the impact of radionuclides in marine ecosystems?

This paper focuses on how a community of researchers under the COMET (CO-ordination and iMplementation of a pan European projecT for radioecology) project has improved the capacity of marine radioecology to understand at the process level the behaviour of radionuclides in the marine environment, uptake by organisms and the resulting doses after the Fukushima Dai-ichi nuclear accident occurred in 2011. We present new radioecological understanding of the processes involved, such as the interaction of waterborne radionuclides with suspended particles and sediments or the biological uptake and turnover of radionuclides, which have been better quantified and mathematically described. We demonstrate that biokinetic models can better represent radionuclide transfer to biota in non-equilibrium situations, bringing more realism to predictions, especially when combining physical, chemical and biological interactions that occur in such an open and dynamic environment as the ocean. As a result, we are readier now than we were before the FDNPP accident in terms of having models that can be applied to dynamic situations. The paper concludes with our vision for marine radioecology as a fundamental research discipline and we present a strategy for our discipline at the European and international levels. The lessons learned are presented along with their possible applicability to assess/reduce the environmental consequences of future accidents to the marine environment and guidance for future research, as well as to assure the sustainability of marine radioecology. This guidance necessarily reflects on why and where further research funding is needed, signalling the way for future investigations.

Seasonal variations of zooplankton biomass and size-fractionated abundance in relation to environmental changes in a tropical mangrove estuary in the Straits of Malacca

Seasonal variations of zooplankton community in terms of biomass and size-fractionated densities were studied in a tropical Sangga Kechil river, Matang, Perak from June 2010 to April 2011. Zooplankton and jellyfish (hydromedusae, siphonophores and ctenophores) samples were collected bimonthly from four sampling stations by horizontal towing of a 140-?m plankton net and 500 ?m bongo net, respectively. A total of 12 zooplankton groups consisting of six groups each of mesozooplankon (0.2 mm-2.0 mm) and macrozooplankton (2.0 mm-20.0 cm) were recorded. The total zooplankton density (12375?3339 ind m(-3)) and biomass (35.32?14.56 mg m(-3)) were highest during the northeast (NE) monsoon and southwest (SW) monsoon, respectively, indicating the presence of bigger individuals in the latter season. Mesozooplankton predominated (94%) over the macrozooplankton (6%) during all the seasons, and copepods contributed 84% of the total mesozooplankton abundance. Macrozooplankton was dominated by appendicularians during most of the seasons (43%-97%), except during the NE monsoon (December) when chaetognaths became the most abundant (89% of the total macrozooplankton). BIO-ENV analysis showed that total zooplankton density was correlated with turbidity, total nitrogen and total phosphorus, which in turn was positively correlated to chlorophyll a. Cluster analysis of the zooplankton community showed no significant temporal difference between the SW and NE monsoon season during the study period (> 90% similarity). The present study revealed that the zooplankton community in the tropical mangrove estuary in the Straits of Malacca was dominated by mesoplankton, especially copepods.

Different expression patterns of hepatic cytochrome P450 s during anaphylactic or lipopolysaccharide-induced inflammation

Certain physiological states and diseases can alter the expression and activity of cytochrome P450 s (CYPs), which have the potential to cause unexpected adverse effects. We previously demonstrated that lipopolysaccharide (LPS)-induced inflammation attenuates the induction of CYPs by xenobiotics in mouse liver. In this study, to investigate whether anaphylaxis-induced inflammation affects the hepatic CYPs' expression, we examined the effects of ovalbumin (OVA)-induced anaphylaxis on constitutive CYP mRNA and protein expressions. We also compared these effects with those obtained with LPS treatment. In addition, we examined the tumor necrosis factor (TNF) alpha and interleukin (IL)-113 mRNA levels, because these cytokines are known to be induced by LPS treatment and anaphylactic reactions. LPS treatment decreased the constitutively expressed Cyp1a2, Cyp2c29, and Cyp3al 1 mRNAs, and increased the TNFalpha and IL-1beta mRNAs. LPS treatment also decreased the CYP1A2 and CYP3A protein levels. Anaphylaxis, on the other hand, did not change the levels of the constitutively expressed Cyp1a2, Cyp2c29, or Cyp3a1 1 mRNAs, although it increased the TNFalpha and IL-1beta mRNAs, as observed in the LPS-treated mice. These results suggest that anaphylaxis-induced inflammation had less effect than LPS-induced inflammation on these CYPs in the liver. In contrast, we observed that the expressions of Cyp2b10 mRNA and its protein were quite different from those of the other CYPs in both the anaphylactic and LPS-treated mice. Our findings strongly suggest that the alteration of the constitutive CYPs' expression levels during inflammation varies according to the immunostimulation pathway.

Endoscopic submucosal dissection for superficial esophageal neoplasms using the stag beetle knife

Endoscopic submucosal dissection (ESD) is an accepted standard treatment for early gastric cancer but is not widely used in the esophagus because of technical difficulties. To increase the safety of esophageal ESD, we used a scissors-type device called the stag beetle (SB) knife. The aim of this study was to determine the efficacy and safety of ESD using the SB knife. We performed a single-center retrospective, uncontrolled trial. A total of 38 lesions were excised by ESD from 35 consecutive patients who were retrospectively divided into the following two groups according to the type of knife used to perform ESD: the hook knife (hook group) was used in 20 patients (21 lesions), and the SB knife (SB group) was used in 15 patients (17 lesions). We evaluated and compared the operative time, lesion size, en bloc resection rate, pathological margins free rate, and complication rate in both groups. The operative time was shorter in the SB group (median 70.0 minutes [interquartile range, 47.5-87.0]) than in the hook group (92.0 minutes [interquartile range, 63.0-114.0]) (P = 0.019), and the rate of complications in the SB group was 0% compared with 45.0% in the hook group (P = 0.004). However, the lesion size, en bloc resection rate, and pathological margins free rate did not differ significantly between the two groups. In conclusion, ESD using the SB knife was safer than that using a conventional knife for superficial esophageal neoplasms.

Species concepts in Cercospora: spotting the weeds among the roses

The genus Cercospora contains numerous important plant pathogenic fungi from a diverse range of hosts. Most species of Cercospora are known only from their morphological characters in vivo. Although the genus contains more than 5 000 names, very few cultures and associated DNA sequence data are available. In this study, 360 Cercospora isolates, obtained from 161 host species, 49 host families and 39 countries, were used to compile a molecular phylogeny. Partial sequences were derived from the internal transcribed spacer regions and intervening 5.8S nrRNA, actin, calmodulin, histone H3 and translation elongation factor 1-alpha genes. The resulting phylogenetic clades were evaluated for application of existing species names and five novel species are introduced. Eleven species are epi-, lecto- or neotypified in this study. Although existing species names were available for several clades, it was not always possible to apply North American or European names to African or Asian strains and vice versa. Some species were found to be limited to a specific host genus, whereas others were isolated from a wide host range. No single locus was found to be the ideal DNA barcode gene for the genus, and species identification needs to be based on a combination of gene loci and morphological characters. Additional primers were developed to supplement those previously published for amplification of the loci used in this study.

Retinoic acids up-regulate functional eosinophil-driving receptor CCR3

Eotaxins and their receptor CCR3 have a definitive role for tissue accumulation of eosinophils both under homeostatic and pathologic conditions. However, physiological stimuli that can up-regulate CCR3 in blood-derived human eosinophils have not been recognized. As a prior gene microarray study revealed up-regulation of CCR3 in eosinophils stimulated with retinoic acids (RAs), the expression of functional CCR3 was examined. We found that 9-cis RA and all-trans RA (ATRA) significantly induced surface CCR3 expression regardless of the presence of IL-3 or IL-5. Pharmacological manipulations with receptor-specific agonists and antagonists indicated that retinoic acid receptor-α activation is critical for CCR3 up-regulation. RA-induced CCR3 was associated with its functional capacity, in terms of the calcium mobilization and chemotactic response to eotaxin-1 (CCL11). Our study suggests an important role of vitamin A derivatives in the tissue accumulation of eosinophils.

Food webs in Mongolian grasslands: the analysis of 13C and 15N natural abundances

Overgrazing often lowers species richness and productivity of grassland communities. For Mongolian grassland ecosystems, a lack of detailed information about food-web structures makes it difficult to predict the effects of overgrazing on species diversity and community composition. We analysed the delta13C and delta15N signatures of herbaceous plants, arthropods (grouped by feeding habit), wild and domestic mammals, and humans in central Mongolia to understand the predominant food-web pathways in this grassland ecosystem. The delta13C and delta15N values of mammals showed little variation within species, but varied considerably with slope position for arthropods. The apparent isotopic discrimination between body tissue and hair of mammals was estimated as 2.0 per thousand for delta13C and 2.1 per thousand for delta15N, which was large enough to cause overestimation of the trophic level of mammals if not taken into account when using hair samples to measure isotopic enrichment.

Imposex induction is mediated through the Retinoid X Receptor signalling pathway in the neogastropod Nucella lapillus

The imposex phenomenon in female prosobranch gastropods provides one of the best documented examples of endocrine disruption in wildlife. While many field studies have demonstrated the negative impact of tributyltin (TBT) upon female gastropods, the mechanism(s) underlying imposex development has not yet been fully clarified. Over the years several hypotheses have been raised to determine the biochemical and molecular determinants of this process. Nevertheless, the interplay between the different suggested pathways (neuroendocrine, steroid and retinoid) is still unknown. Hence, through a combination of exposure experiments, we show that the 9-cis-retinoic acid (9cisRA), the proposed natural ligand of the retinoic X receptor (RXR), induces imposex in females of Nucella lapillus to the same degree as tributyltin, when administered at similar concentrations (1 microg/g body weight). Methoprene acid, a selective ligand for RXR, also induces imposex, albeit to a lower degree than that of the positive control. In contrast, testosterone significantly induced imposex, but had no effect on female penis induction, while the neuropeptide APGWamide had no effect on imposex development. These results clearly demonstrate that imposex induction in N. lapillus is mediated through the modulation of the RXR signalling pathways. In addition to the effects reported in female dogwhelks, both TBT and RA significantly increased male penis length, thus suggesting that TBT may also impact male secondary sex organs through the RXR signalling pathways. As a step for future studies, we have cloned the orthologue of N. lapillus RXR and provide experimental evidence that it binds 9cisRA. Finally, the basal expression level of RXR in several tissues of N. lapillus was determined through real-time PCR, thus showing that RXR is ubiquitously expressed in mollusc tissues, with the highest expression levels being recorded in female and male gonads. The mechanistic impacts of the overall findings to the imposex process are discussed.

Interferometric Coupling of the Keck Telescopes with Single-Mode Fibers

Here we report successful interferometric coupling of two large telescopes with single-mode fibers. Interference fringes were obtained in the 2- to 2.3-micrometer wavelength range on the star 107 Herculis by using the two Keck 10-meter telescopes, each feeding their common interferometric focus with 300 meters of single-mode fibers. This experiment demonstrates the potential of fibers for future kilometric arrays of telescopes and is the first step toward the 'OHANA (Optical Hawaiian Array for Nanoradian Astronomy) interferometer at the Mauna Kea observatory in Hawaii. It opens the way to sensitive optical imagers with resolutions below 1 milli-arc second. Our experimental setup can be directly extended to large telescopes separated by many hundreds of meters.

Wild-type p53 activates SAP expression in lymphoid cells

SAP is an adaptor molecule with one SH2 domain and it is expressed in activated T and NK cells, where it is required for the appropriate signaling from the SLAM family of surface receptors. Deleted or mutated SAP genes that encode functionally defective protein are associated with the X-linked lymphoproliferative disease (XLP). This primary immunodeficiency is characterized by extreme sensitivity to Epstein-Barr virus (EBV) infection, dysgammaglobulinemia and a high rate of lymphoma development. The vigorous T- and B-cell proliferation that follows EBV infection and the high incidence of lymphomas (30%) in XLP patients might reflect functional defects in cell cycle and/ or apoptosis control. Our experiments show that SAP is a target of p53. In Burkitt lymphoma (BL) lines transfected with a temperatur-sensitive (ts) p53, SAP mRNA and protein expression was dependent on wild-type (wt) p53. Activation of endogenous wt p53 in BLs and lymphoblastoid cell lines led to the induction of SAP and this was inhibited by the specific p53 inhibitor pifithrin-alpha. Cell lines that carried mutant p53 did not express SAP under similar conditions. Moreover, we have shown binding of wt p53 to the promoter region of SAP by ChIP assay. Our results suggest that SAP contributes to the execution of some p53 functions.

Estrogenic and thyroid hormone activity of a series of hydroxy-polychlorinated biphenyls

A series of novel synthetic monohydroxy polychlorinated biphenyls (OH-PCBs) (5 trichloro-, 5 tetrachloro- and 5 pentachloro-compounds) have been characterized (1H and 13C NMR and high resolution MS) and their estrogenic and thyroid hormone activities assessed using a yeast two-hybrid assay, both with and without possible metabolic activation by rat liver S9 preparation. Moderate estrogenic activity was found for 2,3,4(')-trichlorobiphenyl-4-ol (compound 5) but this was eliminated when exposed to the S9 mix. 2,2('),3('),4,6-Pentachlorobiphenyl-3-ol (13) and 2('),3,3('),6-tetrachlorobiphenyl-4-ol (10) both showed weak estrogenicity in the absence of the S9 mix. The estrogenicity of compound (10) was enhanced 10-fold by exposure to S9 metabolic activation but that of compound (13) remained unchanged. 2('),4,5('),6-Tetrachlorobiphenyl-2-ol (6) showed strong thyroid hormonal activity (5% of that of T4) whereas 3('),4,6-trichlorobiphenyl-3-ol (4), compound (10) and 2,3('),4,5('),6-pentachlorobiphenyl-3-ol (14) showed moderate activity, and 2('),3,3('),5-tetrachlorobiphenyl-2-ol (8) and 3,3('),5,5('),6-pentachlorobiphenyl-2-ol (11) showed weak activity. The activity of (4) was eliminated by S9 metabolic activation whereas those of (6) and (14) were weakened and that of (10) remained unchanged.

High prevalence of Epstein-Barr virus in gastric remnant carcinoma after Billroth-II reconstruction

BACKGROUND

Epstein-Barr virus (EBV) has been detected in about 10% of gastric carcinoma cases worldwide, and a high prevalence of EBV involvement in gastric remnant carcinoma has been reported recently. Details of the background remnant stomach of EBV-positive lesions, however, have not been well clarified.

METHODS

We screened 17 consecutive gastric remnant carcinoma lesions resected surgically. To detect EBV, we used in situ hybridization (ISH) for EBV-encoded small RNA1 (EBER-1) and we compared the clinicopathologic feature between EBV-positive and -negative gastric remnant carcinoma cases.

RESULTS

EBV was detected in 41.8% (7 of 17) of the lesions by EBER-1 ISH. All 7 EBV-positive lesions developed in the anastomotic site had undergone Billroth-II reconstruction excess 20 years previously (mean 26.4 years). Histologically, all EBV-positive lesions were poorly differentiated adenocarcinomas with intense lymphocyte infiltration. In the adjacent mucosa of carcinomas, moderate or marked intestinal metaplasia was found in 85.7% (6 of 7) of EBV-positive lesions and in 40% (4 of 10) of EBV-negative lesions.

CONCLUSIONS

EBV infection is strongly associated with gastric remnant carcinoma. Atrophic change of remnant gastritis in Billroth-II anastomoses is considered to be the carcinogenic background for EBV-positive gastric remnant carcinoma.

High prevalence of Epstein-Barr virus in gastric remnant carcinoma after Billroth-II reconstruction

BACKGROUND

Epstein-Barr virus (EBV) has been detected in about 10% of gastric carcinoma cases worldwide, and a high prevalence of EBV involvement in gastric remnant carcinoma has been reported recently. Details of the background remnant stomach of EBV-positive lesions, however, have not been well clarified.

METHODS

We screened 17 consecutive gastric remnant carcinoma lesions resected surgically. To detect EBV, we used in situ hybridization (ISH) for EBV-encoded small RNA1 (EBER-1) and we compared the clinicopathologic feature between EBV-positive and -negative gastric remnant carcinoma cases.

RESULTS

EBV was detected in 41.8% (7 of 17) of the lesions by EBER-1 ISH. All 7 EBV-positive lesions developed in the anastomotic site had undergone Billroth-II reconstruction excess 20 years previously (mean 26.4 years). Histologically, all EBV-positive lesions were poorly differentiated adenocarcinomas with intense lymphocyte infiltration. In the adjacent mucosa of carcinomas, moderate or marked intestinal metaplasia was found in 85.7% (6 of 7) of EBV-positive lesions and in 40% (4 of 10) of EBV-negative lesions.

CONCLUSIONS

EBV infection is strongly associated with gastric remnant carcinoma. Atrophic change of remnant gastritis in Billroth-II anastomoses is considered to be the carcinogenic background for EBV-positive gastric remnant carcinoma.

An arming yeast with the ability to entrap fluorescent 17beta-estradiol on the cell surface

We constructed a novel surface-engineered yeast displaying the ligand-binding domain of the rat estrogen receptor (ERLBD). ERLBD, display of which on the yeast cell surface was confirmed by immunofluorescence, possessed strong binding activity to fluorescent 17beta-estradiol - an analogue of the natural ligand of the estrogen receptor - that was comparable to the activity of the native receptor. Environmental homeostasis has recently been disturbed by endocrine disruptors, which cause confusion in the hormone secretion system. It is therefore very important to identify chemical compounds with hormone-like activity and remove them from the environment. The present results demonstrate that the new arming yeast displaying ERLBD on its cell surface will be capable of screening, entrapping, and removing estradiol-like compounds from the environment.

Tumor development in the Beckwith-Wiedemann syndrome is associated with a variety of constitutional molecular 11p15 alterations including imprinting defects of KCNQ1OT1

Dysregulation of imprinted genes on human chromosome 11p15 has been implicated in Beckwith-Wiedemann syndrome (BWS), an overgrowth syndrome associated with congenital malformations and tumor predisposition. The molecular basis of BWS is complex and heterogeneous. The syndrome is associated with alterations in two distinct imprinting domains on 11p15: a telomeric domain containing the H19 and IGF2 genes and a centromeric domain including the KCNQ1OT1 and CDKNIC genes. It has been postulated that disorders of imprinting in the telomeric domain are associated with overgrowth and cancer predisposition, whereas those in the centromeric domain involve malformations but not tumor development. In this study of 125 BWS cases, we confirm the association of tumors with constitutional defects in the 11p15 telomeric domain; six of 21 BWS cases with uniparental disomy (UPD) of 11p15 developed tumors and one of three of the rare BWS subtype with hypermethylation of the H19 gene developed tumors. Most importantly, we find that five of 32 individuals with BWS and imprinting defects in the centromeric domain developed embryonal tumors. Furthermore, the type of tumors observed in BWS cases with telomeric defects are different from those seen in BWS cases with defects limited to the centromeric domain. Whereas Wilms' tumor was the most frequent tumor seen in BWS cases with UPD for 11p15 or H19 hypermethylation, none of the embryonal tumors with imprinting defects at KCNQ1OT1 was a Wilms' tumor. This suggests that distinct tumor predisposition profiles result from dysregulation of the telomeric domain versus the centromeric domain and that these imprinting defects activate distinct genetic pathways for embryonal tumorigenesis.

Experience with photodynamic therapy (endoscopic laser therapy) for the treatment of early gastric cancer

BACKGROUND/AIMS

Photodynamic therapy has been developed as an endoscopic laser therapy for gastrointestinal malignant tumors. The targets for curative upper gastrointestinal endoscopic therapy are carcinomas that are considered statistically unlikely to be accompanied with metastases to the lymph nodes. Endoscopic mucosal resection is the therapy of first choice for such carcinomas. In the application of photodynamic therapy, we narrow down its practical indications to patients who are not indicated for curative endoscopic treatment by preoperative examination or those with histologic findings of endoscopic mucosal resection specimens who reject surgical treatment or are at high risk in surgical treatment.

METHODOLOGY

The effect of photodynamic therapy using Porfimer sodium and an Excimer dye laser was evaluated endoscopically in 8 lesions of 7 patients with early gastric cancer.

RESULTS

Complete responses were obtained in all patients. As side effects, mild photosensitivity was seen in 6 patients and lasted for several months.

CONCLUSIONS

Photodynamic therapy was safety employed, with success in 7 patients with early gastric cancer. We conclude that photodynamic therapy can be a useful palliative method with high tumor selectivity in the treatment of early gastric cancer.

[Bioassay for endocrine disruptors by using yeast two-hybrid system]

One of the urgent tasks in understanding endocrine disruptors (EDs) is to compile a list of suspected substances among the huge number of chemicals by using the screening test method. An in vitro screening test is a more useful tool for primary selection of suspected EDs. We have developed an assay for EDs using the yeast two-hybrid system. The assay is based on the ligand-dependent interaction of two proteins, a hormone receptor and a coactivator, and the hormonal activity is detected by beta-galactosidase activity. This assay is a very simple and inexpensive test method with high repeatability to detect the agonist, and it is applicable for the detection of antagonist and active compounds after metabolism. Accordingly, it has been used in more than 40 laboratories in Japan. To date, we have tested the estrogenic activity of more than 500 chemicals including natural substances, medicines, pesticides and industrial chemicals. Sixty-four compounds were evaluated as positive and most of these possessed a common structure: phenol with a hydrophobic moiety at the para-position without bulky groups at the ortho-position. These results are expected to facilitate further risk assessment of chemicals, especially EDs.

Linearization and integration of DNA into cells preferentially occurs at intrinsically curved regions from human LINE-1 repetitive element

A bent DNA library was constructed from human genomic DNA, from which a new clone belonging to the human LINE-1 sequence family was isolated and characterized. This clone, with a length of 378 base pairs and termed HBC-1 (human bent clone-1), contained an intrinsically occurring curved DNA structure. By permutation analysis, the center of curvature of this fragment was mapped onto the nucleotide position 886 from the 5' terminus of the complete LINE-1 sequence. Reporter plasmids, which contain HBC-1, were effectively integrated into human chromosome, indicating that the bent DNA structure provides a preferential donor site for the integration of human LINE-1 sequences. The present finding may provide an explanation as to why some inactivated LINE-1 sequences on human chromosomes carry the deletion at their 5' termini.

Imprinting status of 11p15 genes in Beckwith-Wiedemann syndrome patients with CDKN1C mutations

Beckwith-Wiedemann syndrome (BWS) is an imprinting disorder characterized by somatic overgrowth, congenital malformations, and predisposition to childhood tumors. Aberrant expression of multiple imprinted genes, including H19, IGF2, KCNQ1OT1, and CDKN1C, has been observed in BWS patients. It has been estimated that mutations in CDKN1C occur in 12-17% of BWS patients. We have screened 10 autosomal dominant pedigrees and 65 sporadic BWS cases by PCR/heteroduplex analysis and DNA sequencing and have identified four mutations, two of which were associated with biallelic IGF2 expression and normal H19 and KCNQ1OT1 imprinting. One patient demonstrated phenotypic expression of paternally transmitted mutation in this maternally expressed gene, a second proband is the child of one of a pair of monozygotic twin females who carry the mutation de novo, and a third patient exhibited unusual skeletal changes more commonly found in other overgrowth syndromes. When considered with other studies published to date, this work reveals the frequency of CDKN1C mutations in BWS to be only 4.9%. This is the first report of an analysis of the imprinting status of genes in the 11p15 region where CDKN1C mutations were associated with loss of IGF2 imprinting and maintenance of H19 and KCNQ1OT1 imprinting.

[Assessment of hydroxylated metabolites of polychlorinated biphenyls and polychlorinated dibenzofurans as potential estrogens by yeast two-hybrid system]

The estrogenic activities of several hydroxylated metabolites of PCBs and PCDFs were investigated by yeast two-hybrid assay based on the ligand-dependent interaction of estrogen receptor with coactivator. For the hydroxylated PCBs, the order of estrogenic potency was 4-OH-2',4',6'-triCB > 4-OH-4'-monoCB, 4-OH-biphenyl. These compounds were evaluated as 10(3) to 10(4) less potent than 17 beta-estradiol based on the concentrations of test compounds showing 10% activity of 10(-7) M 17 beta-estradiol. 2-OH-3',4,4'-triCB, 4-OH-2',3,4'-triCB and 3-OH-/4-OH-2,2',5,5'-tetraCB, the metabolites of 2,2',5,5'-tetraCB were inactive as estrogens at the highest concentrations used in this study (10(-5) M). Also 4-OH-3,3',4',5-tetraCB, the metabolite of 3,3',4,4'-tetraCB was inactive as estrogen, indicating that this hydroxylated metabolite did not take part in the estrogenic activity of 3,3',4,4'-tetraCB. OH group at 4-position of biphenyl was necessary for the expression of estrogenicity, but one or two chloro-substitution adjacent to OH group inhibited the activity. For the hydroxylated PCDFs, 8-OH-2-monoCDF, 7-OH-3,4-diCDF, 8-OH-3,4-diCDF, 8-OH-3,4,6-triCDF and 3,8-(OH)2-2-monoCDF exhibited estrogenic activity. The estrogenic activity of 3,8-(OH)2-2-monoCDF was comparable to those of 4-OH-2',4',6'-triCB and 4-nonylphenol (mixture of compounds with branched sidechain). The order of activity was 3,8-(OH)2-monoCDF > 8-OH-3,4-diCDF, 7-OH-3,4-diCDF > 8-OH-2-monoCDF, 8-OH-3,4,6-triCDF. These compounds were evaluated as 2.5 x 10(3) to 3 x 10(4) less potent than 17 beta-estradiol. On the other hand, no estrogenic activity was observed for 2-OH-dibenzofuran, 3-OH-2,8-diCDF, 6-OH-3,4-diCDF and 9-OH-3,4-diCDF at concentrations as high as 10(-4) M. Substitution of OH group at 2(8)- or 3(7)-position of dibenzofuran and no chloro-substitution adjacent to OH group was required for the estrogenic activity.

Cloning and functional characterization of chicken p160 coactivator family members

The factors SRC-1, TIF2 and ACTR were identified as interacting with nuclear receptors in a highly ligand-dependent manner. Because the molecular mass of each of these factors is approximately 160 kDa, they are collectively termed p160 coactivators. So far, p160 coactivators have been cloned from human, mouse and Xenopus. We report here the cloning of the chicken homologues of p160 coactivator members. As in human and mouse, chicken has three p160 coactivators. Each gene encodes an approximately 160 kDa protein which exhibits 70-80% amino acid sequence identity to human and mouse p160 coactivators. Chicken p160 coactivators also have the property of interacting with several liganded nuclear receptors. Moreover, we describe an imperfect LXXLL sequence, termed NR box 4, which is located downstream of NR box 3 and conserved between evolutionarily diverse species. The loss of NR box 4 results in a decrease of interaction with the nuclear receptor, which indicates that NR box 4 is required for efficient interaction.

A new technique for monitoring the behaviour of free-ranging Adelie penguins

Measurement of the time allocation of penguins at sea has been a major goal of researchers in recent years. Until now, however, no equipment has been available that would allow measurement of the aquatic and terrestrial behaviour of an Antarctic penguin while it is commuting between the colony and the foraging grounds. A new motion detector, based on the measurement of acceleration, has been used here in addition to current methods of inferring behaviour using data loggers that monitor depth and speed. We present data on the time allocation of Adelie penguins (Pygoscelis adeliae) according to the different types of behaviours they display during their foraging trips: walking, tobogganing, standing on land, lying on land, resting at the water surface, porpoising and diving. To illustrate the potential of this new technique, we compared the behaviour of Adelie penguins during the chick-rearing period in a fast sea-ice region and an ice-free region. The proportion of time spent standing, lying on land and walking during foraging trips was greater for penguins in the sea-ice region (37.6+/−13.3% standing, 21.6+/−15.6% lying and 5.9+/−6.3% walking) than for those in the ice-free region (12.0+/−15.8 % standing, 0.38+/−0.60% lying and 0 % walking), whereas the proportion of time spent resting at the water surface and porpoising was greater for birds in the ice-free region (38.1+/−6.4% resting and 1.1+/−1.1% porpoising) than for those in the sea-ice region (3.0+/−2.3% resting and 0% porpoising; means +/− s.d., N=7 for the sea-ice region, N=4 for the ice-free region). Using this new approach, further studies combining the monitoring of marine resources in different Antarctic sites and the measurement of the energy expenditure of foraging penguins, e.g. using heart rates, will constitute a powerful tool for investigating the effects of environmental conditions on their foraging strategy. This technique will expand our ability to monitor many animals in the field.

Cellulose in the house of the appendicularian Oikopleura rufescens

By electron diffraction analysis, highly crystalline cellulose I beta was found in the house (a special structure in which the tunicate lives) of the appendicularian Oikopleura rufescens. Cellulose microfibrils 20 nm in width were observed in a random array or highly organized with rectangular spacing of 2 to 10 microns in the house. The bundled cellulose microfibrils formed in the inlet filters, which are highly ordered meshwork structures. This paper provides the first account of the existence of cellulose in the house of an appendicularian. Our findings showed that the house and tunic are homologous tissues among the tunicates, and that the common ancestor of the tunicates (ascidians, thaliaceans, and appendicularians) already possessed cellulose-biosynthetic ability.

The transcriptional co-activator P/CAF potentiates TGF-beta/Smad signaling

Smads perform pivotal functions in the intracellular signaling of transforming growth factor-beta (TGF-beta). TGF-beta-mediated activation of TGF-beta type I receptor stimulates the phosphorylation of Smad2 and Smad3 and subsequent heteromeric complex formation with Smad4. The heteromeric Smad complexes translocate into the nucleus where they, in co-operation with co-activators and co-repressors, regulate transcriptional responses. Here we investigated the possible co-activator function of P/CAF in TGF-beta/Smad signaling. P/CAF was found to interact directly with Smad3 in vitro. Moreover, Smad2 and Smad3 interacted with P/CAF upon TGF-beta type I receptor activation in cultured mammalian cells. The interaction involves the MH2 domain of Smad3 and the N-terminal region of P/CAF. P/CAF potentiated the transcriptional activity of heterologous Gal4-Smad2 and Gal4-Smad3 fusion proteins. In addition, P/CAF potentiated the TGF-beta/Smad3-induced transcriptional responses, which could be further enhanced by co-activators p300 and Smad4. P/CAF may, therefore, activate Smad-mediated transcriptional responses independently or in co-operation with p300/CBP. Our results indicate a direct physical and functional interplay between two negative regulators of cell proliferation, Smad3 and P/CAF.

Molecular cloning and functional characterization of a novel nuclear receptor similar to an embryonic benzoate receptor BXR

Benzoate X receptor (BXR) is a member of the nuclear hormone receptor superfamily and is activated by alkyl esters of amino benzoic acids and expressed during early development stages. We report here a second BXR, which was cloned by screening Xenopus laevis embryonic cDNA libraries. This new BXR, termed BXRbeta, exhibits 97% identity in the DNA-binding domain and 79% identity in the ligand-binding domain in amino acid sequence to previously reported Xenopus BXR. The BXRbeta strongly binds as a heterodimer with retinoid X receptor (RXR) to direct repeats of an AGGTCA motif spaced 4 or 5 base pairs apart and activates transcription by addition of methyprednisolone and dexamethasone as well as amino- and hydroxybenzoates.

Estrogenic activity of chemicals for dental and similar use in vitro

The estrogenic activities of chemicals for dental and similar use were tested by a reporter gene assay (yeast two-hybrid system) and an estrogen/estrogen receptor (ER-alpha) competition binding assay (fluorescence polarization system). Among the 10 chemicals [bisphenol-A (BPA), bis-2-hydroxypropyl methacrylate (Bis-GMA), triethylene glycol dimethacrylate (TEGDMA), methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA), dibutyl phthalate (DBP), n-butyl benzyl phthalate (BBP), n-butyl phthalyl n-butyl glycolate (BPBG), di-2-ethylhexyl phthalate (DEHP), and di-2-ethylhexyl adipate (DOA)], which were diluted with DMSO to concentrations ranging from 5 x 10(-7) to 5 x 10(-3) M, and 17beta-estradiol (E2) as a positive control, BPA and BBP showed estrogenic activity in these two assays, while the remaining eight chemicals did not at the concentrations tested. Additional data, together with in vivo and epidemiological examinations, are required. Such investigations should also provide information on the validity of these methods for testing the estrogenic activity of chemicals.

Evaluation of the heart with magnetic resonance imaging

After compensating for two kinds of motion artifacts caused by cardiac beating and respiration, cardiac magnetic resonance (MR) imaging is now feasible for the diagnosis of various cardiac diseases. Taking cost-effectiveness into consideration, this paper reviews the experiences of preferable indications of cardiac MR imaging by demonstrating the characteristic preciseness and uniqueness that play an important role in obtaining time-volume curves consisting of the theoretically most accurate measurements of left and right ventricular volumes, in overall evaluation of the left ventricular apex and the right ventricle, in delineating the wide range of the coronary arterial tree, in measuring the most precise blood flow volume through the cross-sectional images of the vessels, and in assessing the spatial derivative of the blood flow velocity at the vessel wall, i.e., wall shear rate.

Molecular evidence of complex tissue- and sex-specific mRNA expression of the rat alpha(2u)-globulin multigene family

alpha(2u)-Globulin is well known to be a rat protein encoded by a highly homologous multigene family with more than twenty members. We report here the cloning and identification of major alpha(2u)-globulin mRNA species expressed in various tissues. Initially, eight individual clones (PGCL1-8) were obtained from a male preputial gland cDNA library. Data base analysis with BLAST demonstrated six mRNAs to be novel, all clones being characterized by highly conserved sequence motifs as lipocalins. All cDNAs contained an open reading frame of 543 nucleotides and encode 181 amino acid proteins showing 92.5-98.7% and 87.3-98.3% nucleic and amino acid identity, respectively. Denaturing gradient gel electrophoresis (DGGE) with sequence analysis showed that PGCL4 is a major member in the female mammary gland, and in the submaxillary and lachrymal glands of both sexes, while the counterpart in male liver and the coagulate glands was found to be PGCL1. Numbers of cDNA species including PGCL1 and PGCL4 were found in preputial glands, no sex-related difference being observed. These results directly demonstrate complex tissue- and sex-specific expression of alpha(2u)-globulins in terms of mRNA species, providing useful information for understanding regulation of the alpha(2u)-globulin multigene family.

[Quantitative evaluation for scatter and attenuation correction in 99mTc SPECT--multicenter cooperation phantom study]

A multicenter cooperation phantom study was conducted to evaluate the accuracy of a triple energy window scatter correction technique in combination with various attenuation correction methods for 99mTc single photon emission computed tomography (SPECT) imaging. Six centers participated in this research and the data obtained with seven SPECT instruments were analyzed. The phantom used in the experiment was a 20 x 10 cm cylinder filled with homogeneous 99mTc solution, containing two kinds of cold spots (cold rod phantoms). One had a water-filled cylinder 5.5 cm in diameter positioned 2.5 cm from the center. The other contained 6 water-filled cylinders of various sizes. Contrasts of cold regions were in the range from 74% to 120% (true 100%). Another phantom had the shape of a pie-chart divided into six chambers symmetrically positioned in a cylinder 20 cm in diameter and 10 cm in height. Each chamber had volume of 480 ml and contained homogeneous 99mTc solution of different concentrations. This phantom was used to test for linearity between the radio activity concentration and reconstructed count density (linearity phantom). The intercept of the regression line obtained from the linearity phantom was 8.4 kBq ml-1 without scatter correction and -6.8 kBq ml-1 with scatter correction. Contrast was in the range from 78% to 132% (true 100%). The mean relative error for the measured activity concentration was 4.9% +/- 3.5% (mean +/- sd).

Evaluating the performance of academic medical education administrators

Educators have devoted little attention to formal evaluation of educational administrative personnel. The authors surveyed the educational administrators working in McMaster University's Department of Medicine residency program and found they felt they were receiving little useful feedback. The authors also surveyed the colleagues, residents, and administrative staff with whom the administrators worked and found they felt they had inadequate input into the administrators' evaluation. In response to these results, a measurement instrument was developed based on existing job descriptions and feedback was obtained on administrators' performance from relevant individuals. After three yearly evaluations, administrators and evaluators acknowledged much broader input into evaluation but saw little evaluation-related improvement in performance. Of the administrators, 85% felt the process should continue as did 91% of the evaluators. An evaluation process may not alter perceived performance when it is already good but there may be other benefits to rigorous evaluation.

Clinical implication of left precordial T wave inversions in the presence of complete right bundle branch block

This study was designed to elucidate whether left precordial negative T waves are electrocardiographic indicators for the diagnosis of hypertrophic cardiomyopathy (HCM) even in the presence of complete right bundle branch block (CRBBB). In 7 consecutive patients with CRBBB accompanied by negative T waves in at least one of the left precordial leads (V4, V5, V6, maximal negativity; 1.06 +/- 0.40 mVol) (left precordial negative T wave group) and in 15 randomly selected CRBBB patients without left precordial T wave inversions (control group), echocardiography was performed to rule out underlying diseases causing left ventricular overload and to identify candidates for magnetic resonance (MR) imaging. None had anginal pain indicating ischemic heart disease. When 2-dimensional echocardiography indicated left ventricular hypertrophy with wall thickness > or = 15 mm, the magnitude and distribution of hypertrophy were scrutinized on contiguous left ventricular MR short-axis images. The diagnostic criterion of HCM was the demonstration of hypertrophy with a wall thickness of 20 mm or more on the left ventricular MR short-axis images. All patients in the left precordial negative T wave group had negative T waves in both I (negativity; 0.27 +/- 0.17 mVol) and aVL (negativity; 0.23 +/- 0.14 mVol), whereas none in the control group did. The diagnostic criterion for HCM was fulfilled in six patients in the left precordial negative T wave group. However there were no patients who fulfilled the criterion in the control group. Negative T waves were recorded in the I (negativity; 0.30 +/- 0.17 mVol), aVL (negativity; 0.25 +/- 0.14 mVol), V4 (negativity; 1.03 +/- 0.46 mVol), V5 (negativity; 0.83 +/- 0.37 mVol) and V6 leads (negativity; 0.31 +/- 0.31 mVol) in all patients with HCM, while they were recorded in only 6% of the patients without HCM. In conclusion, the existence of left precordial negative T waves in the presence of CRBBB strongly indicates HCM.

Epstein-Barr virus-associated gastric carcinoma and atrophic gastritis

Although Epstein-Barr virus (EBV) has been reported to be present in some 7% of gastric carcinomas, the nature of the background gastric mucosa of carcinoma has not been elucidated. The authors evaluated the degree of gastritis in the background gastric mucosa of EBV-associated gastric carcinoma. EBV was detected using in situ hybridization for EBV-encoded small ribonucleic acid 1 (EBER-1) in carcinoma cells. The authors compared gastritis in surgically resected stomachs with 8 EBER-1-positive and 16 EBER-1-negative gastric carcinomas of a similar histologic type using histologic variables of the Updated Sydney System. All eight lesions of EBER-1-positive gastric carcinomas had intestinal metaplasia in the background. Mild to moderate glandular atrophy was common in both groups. Many of the tested lesions, 87.5% of EBER-1-positive and 62.5% of EBER-1-negative lesions, were located near the mucosal atrophic border. The background gastric mucosa for EBV-associated gastric carcinomas is rich in atrophic changes. EBV-associated gastric carcinomas are located near the mucosal atrophic border.

Apoptotic cell death of renal tubules in experimental severe acute pancreatitis

BACKGROUND

Recently renal cell apoptosis has been reported in various disorders that result in renal failure. Thus we hypothesized that renal cell injury resulting from apoptosis is involved in renal failure with severe acute pancreatitis.

METHODS

Renal cell apoptosis in kidneys harvested from rats with necrotizing pancreatitis was evaluated by in situ nick-end labeling. Ascitic fluid that had been collected 6 hours after development of pancreatitis was injected into the peritoneal cavities of healthy rats, and renal apoptosis was also evaluated. The apoptosis-inducing activity of the ascitic fluid was estimated in vitro with use of isolated rat renal tubules and the normal rat kidney cell line NRK52E by nuclear staining, cell cycle analysis, and DNA electrophoresis.

RESULTS

Apoptosis was detected by in situ nick-end labeling on the renal tubules 6 hours after induction of pancreatitis in vivo. Similar tubular apoptosis was detected in the rats that had intraperitoneal injection of the ascitic fluid. In in vitro analyses the ascitic fluid induced nuclear and DNA fragmentation on the isolated renal tubules and promoted apoptosis on NRK52E cells in a time-dependent manner.

CONCLUSIONS

Apoptotic cell death of renal tubules occurs in severe acute pancreatitis within several hours and is possibly involved in the mechanism of renal failure through undefined substance(s) in the ascitic fluid associated with pancreatitis.

Deadtime of a single-crystal gamma camera in abdominal imaging

The deadtime of a single-crystal gamma camera depends on the scattering condition, and differs among patients. The aim of this study was to estimate deadtime in posterior abdominal imaging. Radionuclide angiography of the posterior abdominal view was performed in 23 patients with a point source in the field-of-view, and temporal changes in count loss were assessed. The deadtime for each patient was calculated based on the count loss for the point source. The estimated deadtime ranged from 7.83-12.52 microsec, and was significantly correlated with the ratio of body weight in kg to body height in cm (y=13.143x+5.595, r=0.852, p<0.001). Count loss was successfully corrected using the deadtime predicted with the regression equation. In conclusion, the deadtime in posterior abdominal imaging can be predicted for each patient from the body weight and body height. The predicted deadtime may aid in improving the reliability of quantitative measurements by scintigraphic techniques.

Health care trends, Part I. The promise and perils of evidence-based medicine ... panel discussion

Numerous studies have demonstrated that there are wide variations in the way physicians manage similar patients. This suggests that an evidence-based approach could lead to better outcomes with less cost. But practicing evidence-based medicine requires new skills, such as using computerized databases and applying the rules of evidence to primary and integrative studies in the medical literature. The progress of evidence-based medicine will depend in large measure on how quickly these new skills can be developed and integrated into the practice environment. Here's how six experts see the promise and the perils of evidence-based medicine, now and in the new millennium. Part 2 of the panel discussion will explore the new provider team, which includes nurses and, more recently, pharmacists, who are collaborating with physicians to provide disease management and drugs therapy management services.

Involvement of peritoneal macrophage in the induction of cytotoxicity due to apoptosis in ascitic fluid associated with severe acute pancreatitis

The aim of this study was to assess the significance of peritoneal macrophage in inducing cytotoxicity in ascitic fluid associated with severe acute pancreatitis. The involvement of peritoneal macrophage was examined experimentally in rats by macrophage depletion with peritoneal lavage prior to the development of pancreatitis. More than 94% of the cellular components collected from peritoneal cavities by the lavage are macrophages. Although the ascitic fluid collected from the rats with necrotizing pancreatitis showed cytocidal effects via apoptosis on Madin-Darby canine kidney cells in a dose- and time-dependent manner, cytotoxicity or apoptosis-inducing activity almost disappeared from the ascitic fluid by the preceding peritoneal lavage. The ascitic fluid did not show significant differences by the lavage in osmolarity and in concentrations of albumin, bilirubin, amylase, and lipase. Although a slight reduction of tumor necrosis factor-alpha was noted with the lavage, tumor necrosis factor-alpha failed to induce apoptotic cell death in the cells, and the neutralization by antibody ameliorated neither cell death nor apoptosis. We conclude that peritoneal macrophages secrete apoptosis-inducing factor(s) into pancreatitis-associated ascitic fluid, other than tumor necrosis factor-alpha.