Effects of zinc oxide-montmorillonite hybrid on growth performance, intestinal structure, and function of broiler chicken

A total of 450 one-day-old Arbor Acres male chickens were used to investigate the effects of zinc oxide-montmorillonite hybrid (ZnO-MMT) on growth performance, intestinal structure, and function. The birds were allotted to 5 dietary treatments for 21 d, each of which was replicated 6 times with 15 chicks per replicate. The dietary treatments were 1) corn-soybean meal diet (basal, containing 42.35 mg of Zn/kg); 2) basal diet + 600 mg of MMT/kg (equivalent to the MMT in the ZnO-MMT treatment); 3) basal diet + 60 mg of Zn/kg as ZnO; 4) basal diet + 60 mg of Zn/kg as ZnO-MMT; and 5) basal diet + 60 mg of Zn/kg as ZnSO(4)•7H(2)O. The results showed that chicks fed ZnO-MMT had higher (P < 0.05) ADG and feed intake than those fed the basal diet, MMT, or ZnO. Compared with the control, MMT, ZnO, or ZnSO(4), supplementation with ZnO-MMT decreased (P < 0.05) viable counts of Clostridium in small intestinal and cecal contents, increased (P < 0.05) colonic transepithelial electrical resistance (TER) values, and reduced (P < 0.05) colonic probe mannitol permeability as well as ileal or colonic inulin permeability. Compared with the control, supplemental ZnO-MMT increased (P < 0.05) villus height, the ratio of villus height to crypt depth at the small intestinal mucosa, the trypsin activity in the pancreas, and the digestive enzyme activities in small intestinal contents. Compared with the control, supplementation with ZnO increased (P < 0.05) the villus height and the villus height to crypt depth ratio at the duodenum. Supplementation with ZnSO(4) increased the trypsin activity in pancreas and small intestinal contents. However, supplemental MMT, ZnO, or ZnSO(4) did not affect (P > 0.05) growth performance, ileal and colonic barrier function, and intestinal microflora. The results indicated that supplementing 60 mg of Zn/kg as ZnO-MMT in broiler chickens improved growth performance, intestinal microflora, intestinal morphology, and barrier function as well as the digestive enzyme activities.

Symptoms of Fern Distortion Syndrome resulting from inoculation with opportunistic endophytic fluorescent Pseudomonas spp

BACKGROUND

Fern Distortion Syndrome (FDS) is a serious disease of Leatherleaf fern (Rumohra adiantiformis). The main symptom of FDS is distortion of fronds, making them unmarketable. Additional symptoms include stunting, irregular sporulation, decreased rhizome diameter, and internal discoloration of rhizomes. We previously reported an association of symptoms with increased endophytic rhizome populations of fluorescent pseudomonads (FPs). The aim of the current study was to determine if FPs from ferns in Costa Rica with typical FDS symptoms would recreate symptoms of FDS.

METHODOLOGY AND FINDINGS

Greenhouse tests were conducted over a 29-month period. Micro-propagated ferns derived from tissue culture were first grown one year to produce rhizomes. Then, using an 8×9 randomized complete block experimental design, 8 replicate rhizomes were inoculated by dipping into 9 different treatments before planting. Treatments included water without bacteria (control), and four different groups of FPs, each at a two concentrations. The four groups of FPs included one group from healthy ferns without symptoms (another control treatment), two groups isolated from inside rhizomes of symptomatic ferns, and one group isolated from inside roots of symptomatic ferns. Symptoms were assessed 12 and 17 months later, and populations of FPs inside newly formed rhizomes were determined after 17 months. Results showed that inoculation with mixtures of FPs from ferns with FDS symptoms, but not from healthy ferns, recreated the primary symptom of frond deformities and also the secondary symptoms of irregular sporulation, decreased rhizome diameter, and internal discoloration of rhizomes.

CONCLUSIONS

These results suggest a model of causation of FDS in which symptoms result from latent infections by multiple species of opportunistic endophytic bacteria containing virulence genes that are expressed when populations inside the plant reach a minimum level.

Early weaning increases intestinal permeability, alters expression of cytokine and tight junction proteins, and activates mitogen-activated protein kinases in pigs

Although weaning stress has been reported to impair intestinal barrier function, the mechanisms have not yet been elucidated. In the present study, the intestinal morphology and permeability and mRNA expressions of tight junction proteins and cytokines in the intestine of piglets during the 2 wk after weaning were assessed. The phosphorylated (activated) ratios of p38, c-Jun NH(2)-terminal kinase (JNK), and extracellular regulated kinases (ERK1/2) were determined to investigate whether mitogen-activated protein kinase (MAPK) signaling pathways are involved in the early weaning process. A shorter villus and deeper crypt were observed on d 3 and 7 postweaning. Although damaged intestinal morphology recovered to preweaning values on d 14 postweaning, the intestinal mucosal barrier, which was reflected by transepithelial electrical resistance (TER) and paracellular flux of dextran (4 kDa) in the Ussing chamber and tight junction protein expression, was not recovered. Compared with the preweaning stage (d 0), jejunal TER and mRNA expressions of occludin and claudin-1 on d 3, 7, and 14 postweaning and Zonula occludens-1 (ZO-1) mRNA on d 3 and 7 postweaning were reduced, and paracellular flux of dextran on d 3, 7, and 14 postweaning was increased. An increase (P < 0.05) of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA on d 3 and d 7 postweaning and an increase (P < 0.05) of interferon-γ (IFN-γ) mRNA on d 3 postweaning were observed compared with d 0. No significant increase of transforming growth factor β1 (TGF-β1) and interleukin-10 (IL-10) mRNA after weaning was observed. The phosphorylated (activated) ratios of JNK and p38 on d 3 and 7 postweaning and the phosphorylated ratio of ERK1/2 on d 3 postweaning were increased (P < 0.05) compared with d 0. The results indicated that early weaning induced sustained impairment in the intestinal barrier, decreased mRNA expression of tight junction proteins, and upregulated the expression of proinflammatory cytokines, but anti-inflammatory cytokines were not affected in the intestine of piglets. The recovery of the intestinal barrier function was slower than that of the intestinal mucosal morphology. The weaning stress activated MAPK signaling pathways in the intestine, which may be an important mechanism of weaning-associated enteric disorders of piglets.

Effects of broccoli stem and leaf meal on broiler performance, skin pigmentation, antioxidant function, and meat quality

Three hundred sixty 1-d-old Ross 308 male broilers were used to study the effects of broccoli stem and leaf meal (BSLM) on growth performance, skin pigmentation, antioxidant function, and meat quality. The chicks were fed 4 diets containing different levels (0, 4.0, 8.0, and 12.0%) of BSLM as partial replacement for corn and soybean meal for a period of 42 d. The results showed that dietary supplementation of BSLM had no effect (P > 0.05) on growth performance. As compared with control, dietary 4%, 8%, and 12% BSLM increased (P < 0.05) b value (yellowness) both in shank and breast skin, increased (P < 0.05) the concentrations of xanthophylls in abdominal fat and breast skin, improved (P < 0.05) total antioxidant capability, lowered malondialdehyde concentration, and decreased drip loss percentage of breast muscle. Dietary 8% and 12% BSLM decreased (P < 0.05) shank L values (lightness), increased (P < 0.05) shank a value (redness), and increased (P < 0.05) the activities of superoxide dismutase and catalase of breast muscle as compared with control. The results indicated that dietary supplementation of BSLM in broiler chickens improved the poultry products quality with the more skin pigmentation and the less drip loss percentage of breast meat. The more skin pigmentation mainly related to the high amount of xanthophylls in BSLM. The decreased meat drip loss fed BSLM may be caused by the antioxidative function of BSLM.

Bioinformatics analysis with graph-based clustering to detect gastric cancer-related pathways

Despite a dramatic reduction in incidence and mortality rates, gastric cancer still remains one of the most common malignant tumors worldwide, especially in China. We sought to identify a set of discriminating genes that could be used for characterization and prediction of response to gastric cancer. Using bioinformatics analysis, two gastric cancer datasets, GSE19826 and GSE2685, were merged to find novel target genes and domains to explain pathogenesis; we selected differentially expressed genes in these two datasets and analyzed their correlation in order to construct a network. This network was examined to find graph clusters and related significant pathways. We found that ALDH2 and CCNB1 were associated with gastric cancer. We also mined for the underlying molecular mechanisms involving these differently expressed genes. We found that ECM-receptor interaction, focal adhesion, and cell cycle were among the significantly associated pathways. We were able to detect genes and pathways that were not considered in previous research on gastric cancer, indicating that this approach could be an improvement on the investigative mechanisms for finding genetic associations with disease.

Recent Genotypes of Phytophthora infestans in the Eastern United States Reveal Clonal Populations and Reappearance of Mefenoxam Sensitivity

Isolates of Phytophthora infestans (n = 178) were collected in 2002 to 2009 from the eastern United States, Midwestern United States, and eastern Canada. Multilocus genotypes were defined using allozyme genotyping, and DNA fingerprinting with the RG-57 probe. Several previously described and three new mulitilocus genotypes were detected. The US-8 genotype was found commonly on commercial potato crops but not on tomato. US-20 was found on tomato in North Carolina from 2002 through 2007 and in Florida in 2005. US-21 was found on tomato in North Carolina in 2005 and Florida in 2006 and 2007. US-22 was detected on tomato in 2007 in Tennessee and New York and became widespread in 2009. US-22 was found in 12 states on tomato and potato and was spread on tomato transplants. This genotype accounted for about 60% of all the isolates genotyped. The US-23 genotype was found in Maryland, Virginia, Pennsylvania, and Delaware on both tomato and potato in 2009. The US-24 genotype was found only in North Dakota in 2009. A1 and A2 mating types were found in close proximity on potato and tomato crops in Pennsylvania and Virginia; therefore, the possibility of sexual reproduction should be monitored. Whereas most individuals of US-8 and US-20 were resistant to mefenoxam, US-21 appeared to be intermediately sensitive, and isolates of US-22, US-23, and US-24 were largely sensitive to mefenoxam. On the basis of sequence analysis of the ras gene, these latter three genotypes appear to have been derived from a common ancestor. Further field and laboratory studies are underway using simple sequence repeat genotyping to monitor current changes in the population structure of P. infestans causing late blight in North America.

DNA barcoding of oomycetes with cytochrome c oxidase subunit I and internal transcribed spacer

Oomycete species occupy many different environments and many ecological niches. The genera Phytophthora and Pythium for example, contain many plant pathogens which cause enormous damage to a wide range of plant species. Proper identification to the species level is a critical first step in any investigation of oomycetes, whether it is research driven or compelled by the need for rapid and accurate diagnostics during a pathogen outbreak. The use of DNA for oomycete species identification is well established, but DNA barcoding with cytochrome c oxidase subunit I (COI) is a relatively new approach that has yet to be assessed over a significant sample of oomycete genera. In this study we have sequenced COI, from 1205 isolates representing 23 genera. A comparison to internal transcribed spacer (ITS) sequences from the same isolates showed that COI identification is a practical option; complementary because it uses the mitochondrial genome instead of nuclear DNA. In some cases COI was more discriminative than ITS at the species level. This is in contrast to the large ribosomal subunit, which showed poor species resolution when sequenced from a subset of the isolates used in this study. The results described in this paper indicate that COI sequencing and the dataset generated are a valuable addition to the currently available oomycete taxonomy resources, and that both COI, the default DNA barcode supported by GenBank, and ITS, the de facto barcode accepted by the oomycete and mycology community, are acceptable and complementary DNA barcodes to be used for identification of oomycetes.

Genetic structure of Phytophthora infestans populations in China indicates multiple migration events

One hundred isolates of Phytophthora infestans collected from 10 provinces in China between 1998 and 2004 were analyzed for mating type, metalaxyl resistance, mitochondrial DNA (mtDNA) haplotype, allozyme genotype, and restriction fragment length polymorphism (RFLP) with the RG-57 probe. In addition, herbarium samples collected in China, Russia, Australia, and other Asian countries were also typed for mtDNA haplotype. The Ia haplotype was found during the first outbreaks of the disease in China (1938 and 1940), Japan (1901, 1930, and 1931), India (1913), Peninsular Malaysia (1950), Nepal (1954), The Philippines (1910), Australia (1917), Russia (1917), and Latvia (1935). In contrast, the Ib haplotype was found after 1950 in China on both potato and tomato (1952, 1954, 1956, and 1982) and in India (1968 and 1974). Another migration of a genotype found in Siberia called SIB-1 (Glucose-6-phosphate isomerase [Gpi] 100/100, Peptidase [Pep] 100/100, IIa mtDNA haplotype) was identified using RFLP fingerprints among 72% of the isolates and was widely distributed in the north and south of China and has also been reported in Japan. A new genotype named CN-11 (Gpi 100/111, Pep 100/100, IIb mtDNA haplotype), found only in the south of China, and two additional genotypes (Gpi 100/100, Pep 100/100, Ia mtDNA haplotype) named CN-9 and CN-10 were identified. There were more diverse genotypes among isolates from Yunnan province than elsewhere. The SIB-1 (IIa) genotype is identical to those from Siberia, suggesting later migration of this genotype from either Russia or Japan into China. The widespread predominance of SIB-1 suggests that this genotype has enhanced fitness compared with other genotypes found. Movement of the pathogen into China via infected seed from several sources most likely accounts for the distribution of pathogen genotypes observed. MtDNA haplotype evidence and RFLP data suggest multiple migrations of the pathogen into China after the initial introduction of the Ia haplotype in the 1930s.

Kimura's disease mimicking an earlobe keloid

Kimura's disease (KD) is a rare chronic inflammatory disorder of unknown aetiology. It usually presents as soft-tissue masses predominantly in the head or neck region. We report a case of an asymptomatic tumour on the left earlobe mimicking a keloid. The tumour was histopathologically diagnosed as KD. This case suggests the importance of conducting skin biopsies of keloidal lesions on head and neck regions, particularly in patients who have peripheral eosinophilia and increased IgE levels.

Phylogenetic relationships of Phytophthora andina, a new species from the highlands of Ecuador that is closely related to the Irish potato famine pathogen Phytophthora infestans

Phylogenetic relationships of Phytophthora infestans sensu lato in the Andean highlands of South America were examined. Three clonal lineages (US-1, EC-1, EC-3) and one heterogeneous lineage (EC-2) were found in association with different host species in genus Solanum. The EC-2 lineage includes two mitochondrial (mtDNA) haplotypes, Ia and Ic. Isolates of P. infestans sensu lato EC-2 fit the morphological description of P. infestans but are different from any genotypes of P. infestans described to date. All isolates of P. infestans sensu lato from Ecuador were amplified by a P. infestans specific primer (PINF), and restriction fragment length patterns were identical in isolates amplified with ITS primers 4 and 5. The EC-1 clonal lineage of P. infestans sensu lato from S. andreanum, S. columbianum, S. paucijugum, S. phureja, S. regularifolium, S. tuberosum and S. tuquerense was confirmed to be P. infestans based on sequences of the cytochrome oxidase I (cox I) gene and intron 1 of ras gene. The EC-2 isolates with the Ic haplotype formed a distinct branch in the same clade with P. infestans and P. mirabilis, P. phaseoli and P. ipomoeae for both cox I and ras intron 1 phylogenies and were identified as the newly described species P. andina. Ras intron 1 sequence data suggests that P. andina might have arisen via hybridization between P. infestans and P. mirabilis.

First-principles investigations of the pressure-induced structural transitions in Mg(AlH(4))(2)

A systematic investigation is presented of the high-pressure structural stability of Mg(AlH(4))(2) using a plane-wave pseudo-potential method. The total-energy calculations show that under ambient pressure the structure of α-Mg(AlH(4))(2) found by experiments is more stable than the other proposed structures, and with pressure increasing the α to β (δ-Zr(MoO(4))(2)-type structure) and β to γ (Ca(BF(4))(2)-type structure) transitions occur at 0.67 and 10.28 GPa respectively, accompanied with volume reductions of 6.6% and 8.7%. A detailed study of the electronic structures reveals the bonding characteristics between Al and H and between Mg and H as well as the nonmetallic features of α, β, and γ phases under pressure of up to 20.0 GPa. Their electronic structures are mainly responsible for the relative high-pressure stability of the three phases. Finally, an analysis of their structural relations indicates that it is possible to produce the [Formula: see text] structural transition by applying pressure.

High frequency broadband PZT thick film ultrasonic transducers for medical imaging applications

A modified sol-gel method is used to prepare PZT thick film on Pt-coated silicon substrate. A new method of vacuum filling sol-gel precursor solution is introduced to improve film quality. The effects of the filling on PZT thick film structure and ferroelectric properties are discussed. The fabrication of a high frequency transducer with the PZT film as the actuating layer is described. The performance of the transducer is measured and results show that the transducer backed by E-Solder without a matching layer has a center frequency of 103 MHz and a bandwidth of 70%. Beam profile measurements show that the transducer has an axial resolution of 9.2 microm and a lateral resolution of 33 microm.

No association of cytokine gene polymorphisms in Chinese patients with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a common chronically relapsing skin disease associated with the activation of T-helper 2 cells. Recent studies have shown that polymorphisms in the genes for interleukin (IL)-4, the IL-4 receptor, IL-13, and signal transducer and activator 6 (STAT6) may contribute to susceptibility of AD. To date, no cytokine gene polymorphism study has been conducted on Chinese patients with AD.

AIMS

To determine whether genetic polymorphisms of the cytokine genes might influence the development of AD.

METHODS

DNA samples were obtained from 94 patients and 186 control subjects. Using direct sequencing and microsatellite genotyping, we examined 22 polymorphisms in eight cytokine genes including the genes for IL-4, -10, -12B and -13, the IL-4 receptor, tumour necrosis factor (TNF)-alpha, STAT6, and interferon (IFN)-gamma.

RESULTS

No significantly different allelic and genotypic distributions of the cytokine gene polymorphisms could be found between patients and controls. Moreover, no association was observed with disease onset, gender, the presence of elevated serum total IgE level or blood eosinophilia.

CONCLUSION

Our study suggests that the analysed genetic polymorphisms of cytokine genes do not appear to be associated with AD susceptibility in our Chinese population.

Antibacterial effect of Cu2+-exchanged montmorillonite on Aeromonas hydrophila and discussion on its mechanism

Montmorillonite (MMT) and its Cu2+-exchanged montmorillonite (Cu-MMT) were used to study the antibacterial activity on Aeromonas hydrophila. The results indicated that MMT had no antibacterial activity. The minimum inhibitory concentration (MIC) and bactericidal concentration (MBC) of Cu-MMT on A. hydrophila are found to be 150 and 600 mg/L, respectively. The continuance of the antibacterial activity of Cu-MMT was much longer than copper sulfate. In order to reveal the mechanism of the antibacterial activity of Cu-MMT, the Cu release from Cu-MMT in tryptic soy broth (TSB) was investigated. In the first 2 h, Cu concentration in the supernatant reaches saturated value, about 1.22-2.27% of the overall Cu in Cu-MMT suspended in the medium. The washed Cu-MMT in TSB for 24 h retained their full antibacterial activity; whereas, the supernatants from the washed pellets showed very little antibacterial activity. These findings suggested that the antibacterial activity of Cu-MMT was mainly localized on the clay surface, and not due to the release of Cu2+ into solution. The excessive positive charge of Cu-MMT would make Cu-MMT attract A. hydrophila with negatively charged cellular wall. In this case, the copper cation would act directly on the bacteria adsorbed on the surface of Cu-MMT, instead of into the medium. The mechanism for the antibacterial activity of Cu-MMT may involve the enhanced affinity of Cu-MMT for A. hydrophila and the antibacterial activity of Cu2+.

CYP2K6 from zebrafish (Danio rerio): cloning, mapping, developmental/tissue expression, and aflatoxin B1 activation by baculovirus expressed enzyme

A full-length zebrafish (Danio rerio) cytochrome P450 (CYP) 2K6 cDNA, was obtained (GenBank accession No. AF283813) through polymerase chain reaction cloning using degenerated primers based on a consensus CYP2 sequence and the heme-binding domain. This first CYP2K family member cloned from zebrafish had 1861 bp which contained 27 bp of 5'-untranslated region (5'-UTR), an open reading frame (ORF) of 1518 bp, and a 300 bp 3'-UTR with a poly A tail. The deduced 506 amino acid sequence of CYP2K6 had 63%, 62% and 59% identity with rainbow trout CYP2K1, CYP2K4 and CYP2K3, respectively; and 45%, 42%, and 42% identity with rabbit CYP2C1, human CYP2C19 and mouse CYP2C39, respectively. CYP2K6 mapped to 107.49cR on LG3 using the LN54 radiation hybrid panel. Its mRNA was detected at 5 days post-fertilization and in the adult liver and ovary among nine tissues examined. The ORF, including the 27 bp of the 5'-UTR, was cloned into pFastBac donor vector and then transferred into the baculovirus genome (bacmid DNA) in DH10Bac competent cells. The recombinant bacmid DNA was used to infect Spodoptera frugiperda insect cells to express the CYP2K6 protein (Bv-2K6). As its ortholog, rainbow trout Bv-2K1 [Yang, Y.H., Miranda, C.L., Henderson, M.C., Wang-Buhler, J.-L., Buhler, D.R., 2000. Heterologous expression of CYP2K1 and identification of the expressed protein (Bv-2K1) as lauric acid (omega-1)-hydroxylase and aflatoxin B1 exo-epoxidase. Drug Metab. Disp. 28,1279-83.], Bv-2K6 also catalyzed the conversion of aflatoxin B1 (AFB1) to its exo-8,9-epoxide as assessed by the trapping of a glutathione (GSH) adduct in the presence of a specific mouse alpha class glutathione S-transferase. The identity of the AFB1-GSH adduct was verified by liquid chromatography-mass spectrometry (LC-MS) and mass spectrometry-mass spectrometry (MS-MS) analysis. Although rainbow trout Bv-2K1 was capable of oxidizing lauric acid, zebrafish Bv-2K6 protein showed no activity against this substrate.

Effects of copper-bearing montmorillonite on growth performance, digestive enzyme activities, and intestinal microflora and morphology of male broilers

Avian commercial male broiler chicks (n = 240), 1 d of age, were used to investigate the effects of copper-bearing montmorillonite (Cu-MMT) on growth performance, digestive enzyme activities, and intestinal microflora and morphology. The chicks were allocated to 4 treatments, each of which had 5 pens of 12 chicks per pen. The 4 treatments were basal diet only (control group), basal diet + 1.5 g/kg montmorillonite (MMT), basal diet + 36.75 mg/kg Cu, in the form of CuSO4, and basal diet + 1.5 g/kg Cu-MMT. The results showed that supplementation with Cu-MMT significantly improved growth performance compared with the control diet, and that chicks fed with Cu-MMT had higher average daily gain (ADG) than those fed with MMT or CuSO4. Supplementation with Cu-MMT significantly reduced the total viable counts of Escherichia coli and Clostridium in the small intestine and cecum. Supplementation with MMT or CuSO4 had no influence on intestinal microflora. Chicks fed with Cu-MMT had lower viable counts of E. coli in cecal contents than those fed with MMT or CuSO4. The addition of either MMT or Cu-MMT to the diet improved the activities of total protease, amylase, and lipase in the small intestinal contents but had no effect on those in the pancreas. Morphological measurements of the small intestinal mucosa of chicks indicated that dietary addition of MMT or Cu-MMT improved intestinal mucosal morphology.

Bacterial volatiles induce systemic resistance in Arabidopsis

Plant growth-promoting rhizobacteria, in association with plant roots, can trigger induced systemic resistance (ISR). Considering that low-molecular weight volatile hormone analogues such as methyl jasmonate and methyl salicylate can trigger defense responses in plants, we examined whether volatile organic compounds (VOCs) associated with rhizobacteria can initiate ISR. In Arabidopsis seedlings exposed to bacterial volatile blends from Bacillus subtilis GB03 and Bacillus amyloliquefaciens IN937a, disease severity by the bacterial pathogen Erwinia carotovora subsp. carotovora was significantly reduced compared with seedlings not exposed to bacterial volatiles before pathogen inoculation. Exposure to VOCs from rhizobacteria for as little as 4 d was sufficient to activate ISR in Arabidopsis seedlings. Chemical analysis of the bacterial volatile emissions revealed the release of a series of low-molecular weight hydrocarbons including the growth promoting VOC (2R,3R)-(-)-butanediol. Exogenous application of racemic mixture of (RR) and (SS) isomers of 2,3-butanediol was found to trigger ISR and transgenic lines of B. subtilis that emitted reduced levels of 2,3-butanediol and acetoin conferred reduced Arabidopsis protection to pathogen infection compared with seedlings exposed to VOCs from wild-type bacterial lines. Using transgenic and mutant lines of Arabidopsis, we provide evidence that the signaling pathway activated by volatiles from GB03 is dependent on ethylene, albeit independent of the salicylic acid or jasmonic acid signaling pathways. This study provides new insight into the role of bacteria VOCs as initiators of defense responses in plants.

Different signaling pathways of induced resistance by rhizobacteria in Arabidopsis thaliana against two pathovars of Pseudomonas syringae

•  The mechanisms by which plant growth-promoting rhizobacteria (PGPR) mediate induced systemic resistance are currently being intensively investigated from the viewpoint of signal transduction pathways within plants. •  Here, we determined whether our well-characterized PGPR strains, which have demonstrated induced resistance on various plants, also elicit induced resistance in Arabidopsis thaliana. Nine different PGPR strains were evaluated for their capacity to cause induced resistance on Arabidopsis against two pathovars of Pseudomonas syringae. Six strains significantly reduced severity of P. syringae pv. tomato, whereas seven strains reduced severity of P. syringae pv. maculicola. •  From the initial screenings, four strains (90-166, SE34, 89B61 and T4) were selected because of their consistent induced resistance capacity. Elicitation of induced resistance with these strains depended on how disease severity was measured. Three strains (90-166, 89B61 and T4) induced resistance in NahG plants (SA-deficient), indicating a salicylic acid-independent pathway, which agrees with the previously reported pathway for induced resistance by PGPR. However, differences from the reported pathway were noted with strain 89B61, which did not require jasmonic acid or ethylene signaling pathways for induced resistance, and with strain T4, which induced resistance in npr1 plants. •  These results indicate that strains 89B61 and T4 induce resistance via a new pathway or possibly a variation of the previously reported pathway. This information will broaden our understanding of ways in which microorganisms can signal physiological changes in plants.

Effects of dietary fructooligosaccharide on digestive enzyme activities, intestinal microflora and morphology of male broilers

Two hundred forty male Avian Farms broiler chicks, 1 d of age, were randomly allocated to four treatments, each of which had five pens of 12 chicks per pen. The chicks were used to investigate the effects of fructooligosaccharide (FOS) on digestive enzyme activities and intestinal microflora and morphology. The chicks received the same basal diet based on corn-soybean meal, and FOS was added to the basal diet at 0, 2.0, 4.0, and 8.0 g/kg diet at the expense of corn. Addition of 4.0 g/kg FOS to the basal diet significantly increased average daily gain of broilers. The feed-to-gain ratios were significantly decreased for the birds fed diets with 2.0 and 4.0 g/kg FOS versus the control. Addition of 4.0 g/kg FOS enhanced the growth of Bifidobacterium and Lactobacillus, but inhibited Escherichia coli in the small intestinal and cecal digesta. Supplementation of 2.0 or 4.0 g/kg FOS to chicks significantly improved the activities of amylase compared to the control (12.80 or 14.75 vs. 8.42 Somogyi units). A significant increase in the activities of total protease was observed in 4.0 g/kg FOS-treated birds versus controls (83.91 vs. 65.97 units). Morphology data for the duodenum, jejunum, and ileum showed no significant differences for villus height, crypt depth, or microvillus height at the duodenum. By contrast, addition of 4.0 g/kg FOS significantly increased ileal villus height, jejunal and ileal microvillus height, and villus-height-to-crypt-depth ratios at the jejunum and ileum and decreased crypt depth at the jejunum and ileum. However, addition of 8.0 g/kg FOS had no significant effect on growth performance, digestive enzyme activities, intestinal microflora, or morphology.

Bacterial volatiles promote growth in Arabidopsis

Several chemical changes in soil are associated with plant growth-promoting rhizobacteria (PGPR). Some bacterial strains directly regulate plant physiology by mimicking synthesis of plant hormones, whereas others increase mineral and nitrogen availability in the soil as a way to augment growth. Identification of bacterial chemical messengers that trigger growth promotion has been limited in part by the understanding of how plants respond to external stimuli. With an increasing appreciation of how volatile organic compounds signal plants and serve in plant defense, investigations into the role of volatile components in plant-bacterial systems now can follow. Here, we present chemical and plant-growth data showing that some PGPR release a blend of volatile components that promote growth of Arabidopsis thaliana. In particular, the volatile components 2,3-butanediol and acetoin were released exclusively from two bacterial strains that trigger the greatest level of growth promotion. Furthermore, pharmacological applications of 2,3-butanediol enhanced plant growth whereas bacterial mutants blocked in 2,3-butanediol and acetoin synthesis were devoid in this growth-promotion capacity. The demonstration that PGPR strains release different volatile blends and that plant growth is stimulated by differences in these volatile blends establishes an additional function for volatile organic compounds as signaling molecules mediating plant-microbe interactions.

Limit on the electron neutrino magnetic moment from the kuo-sheng reactor neutrino experiment

A search of neutrino magnetic moment was carried out at the Kuo-Sheng Nuclear Power Station at a distance of 28 m from the 2.9 GW reactor core. With a high purity germanium detector of mass 1.06 kg surrounded by scintillating NaI(Tl) and CsI(Tl) crystals as anti-Compton detectors, a detection threshold of 5 keV and a background level of 1 kg(-1) keV(-1) day(-1) at 12-60 keV were achieved. Based on 4712 and 1250 h of reactor ON and OFF data, respectively, the limit on the neutrino magnetic moment of mu(nu;(e))<1.3x10(-10)mu(B) at 90% confidence level was derived. An indirect bound of the nu;(e) radiative lifetime of m(3)(nu)tau(nu)>2.8x10(18) eV(3) s can be inferred.

Effects of L-carnitine on growth performance, carcass composition, and metabolism of lipids in male broilers

We studied the effects of L-carnitine on growth performance, carcass composition, and lipid metabolism in male broilers. Six hundred male commercial broilers were allotted to five groups, each of which included three replicates (40 birds per replicate). The groups received the same basal diet supplemented with 0, 25, 50, 75, or 100 mg/kg L-carnitine, respectively. The feeding trial showed that L-carnitine had no significant effect on daily gain or feed conversion. Supplementation with L-carnitine (above 25 mg/kg) in the diet increased breast muscle yield (P < 0.05) and crude fat content of the muscles and decreased abdominal fat content (P < 0.05). Addition of 50, 75, or 100 mg/kg L-carnitine to the diet decreased total activities of glucose-6-phosphate dehydrogenase, malic dehydrogenase, isocitrate dehydrogenase, and lipoprotein lipase (P < 0.05) in the subcutaneous fat and total activity of carnitine palmitoyltransferase-I (P < 0.05) in breast muscles. The results of this study indicate that L-carnitine could reduce the deposit of subcutaneous fat by decreasing total activities of enzymes in the fat and enhance intramuscular fat by decreasing the activity of carnitine palmitoyltransferase-I in breast muscles.

Fall characteristics, functional mobility and bone mineral density as risk factors of hip fracture in the community-dwelling ambulatory elderly

Hip fracture is the most serious consequence of osteoporosis, frequently occurring in the elderly; however, no research has been performed to identify the fall characteristics, functional mobility and bone mineral density (BMD) concurrently as risk factors. We investigated the risk factors of hip fractures using a multifactorial approach for a further preventive strategy. This age- and sex-matched case-control study was conducted in a community-based general hospital. A total of 252 consecutive community-dwelling ambulatory elderly, aged between 65 and 85 years, were studied: 127 patients (faller with hip fracture) and 125 controls (faller without hip fracture). Body mass index (BMI), predisposing medical conditions, fall characteristics, functional mobility and BMD of the hip were evaluated by direct interview and clinical examination. In the final model of multivariate regression analysis, risk factors for hip fracture were direct hip impact (adjusted odds ratio (OR), 4.9; 95% confidence interval (CI), 2.7-8.8), previous stroke (adjusted OR, 2.9; 95% CI, 1.3-6.3), sideways fall (adjusted OR, 2.5; 95% CI, 1.6-3.9), functional mobility (a decrease of 1 SD; adjusted OR, 2.0; 95% CI, 1.1-3.5), BMI (a decrease of 1 SD; adjusted OR, 1.8; 95% CI, 1.1-2.8) and femoral neck BMD (a decrease of 1 SD; adjusted OR, 1.7; 95% CI, 1.0-2.8). The effect of risk factors remained the same in different analysis sets, and adding or removing femoral neck BMD did not change other risk factors, though BMD was significantly correlated with functional mobility and BMI. Importantly, both sideways fall and direct hip impact are independent predictors of hip fracture. From these results, we suggest a preventive strategy of hip fracture in the elderly: besides the maintenance of BMD, keeping an appropriate body weight and maintaining a physically active lifestyle might be crucial.

Three monoalkoxy-substituted nido-platinaboranes: [(PPh3)2PtB10H11-8-(OCH3)], [(PPh3)2PtB10H11-8-[OCH-(CH3)2]] and [(PPh3)2PtB10H10-9-[OCH(CH3)2]]

Each of the title compounds, 8-methoxy-7,7-bis(triphenylphosphine-P)-8,9:10,11-di-muH-7-platina-nido-undecaborane dichloromethane hemisolvate, [Pt(CH(14)B(10)O)(C(18)H(15)P)(2)].0.5CH(2)Cl(2), (I), 8-isopropoxy-7,7-bis(triphenylphosphine-P)-8,9:10,11-di-muH-7-platina-nido-undecaborane dichloromethane solvate, [Pt(C(3)H(18)B(10)O)(C(18)H(15)P)(2)].CH(2)Cl(2), (II), and 9-isopropoxy-7,7-bis(triphenylphosphine-P)-8,9:10,11-di-muH-7-platina-nido-undecaborane dichloromethane solvate, [Pt(C(3)H(18)B(10)O)(C(18)H(15)P)(2)].CH(2)Cl(2), (III), has an 11-vertex nido polyhedral skeleton, with the 7-platinum centre ligating to two exo-polyhedral PPh(3) groups and an alkoxy-substituted polyhedral borane ligand. Compounds (II) and (III) are isomers. The Pt-B distances are in the range 2.214 (7)-2.303 (7) A for (I), 2.178 (16)-2.326 (16) A for (II) and 2.205 (6)-2.327 (6) A for (III).

Transdermal drug delivery enhanced and controlled by erbium:YAG laser: a comparative study of lipophilic and hydrophilic drugs

The influence of an erbium:YAG laser on the transdermal delivery of drugs across skin was studied in vitro. Indomethacin and nalbuphine, which have the same molecular weight, were selected as model lipophilic and hydrophilic drugs, respectively, to compare skin permeation by laser treatment. The results indicate a significant increase in the permeation of indomethacin and nalbuphine across skin pretreated with an erbium:YAG laser. The laser had a greater effect on the permeation of hydrophilic molecules which usually possess low permeability. The laser intensity and its spot size were found to play an important role in controlling transdermal delivery of drugs. Permeation of the hydrophilic drug increased following an increase of laser energy. On the other hand, a different result was observed for the lipophilic drug transported across laser-treated skin. The stratum corneum (SC) layer in skin could be partly ablated by the erbium:YAG laser. The barrier function of the SC may also be modulated by a lower intensity of the laser without affecting the viability and structure of the epidermis/dermis as determined by histological observations. However, ultrastructural alteration of the epidermis/dermis may be caused by laser treatment. Use of an erbium:YAG laser is a good method for enhancing transdermal absorption of both lipophilic and hydrophilic drugs, because it allows precise control of SC removal, and this ablation of SC can be reversible to the original normal status.

Building a generic architecture for medical information exchange among healthcare providers

Due to the inability to exchange clinical information among hospitals, continuity of care cannot be maintained and a tremendous amount of medical resource has been wasted. This paper describes an architecture that would facilitate exchange of clinical information among heterogeneous hospital information systems. It is dubbed 'Medical Information Exchange Center' or MIEC as part of a six-year Health Information Network Project hosted by the Department of Health. MIEC was designed so that it is innovative yet technically feasible today. It is convenient for authorized users yet secure enough so people can trust and has minimal impact to participated hospitals. Authorized users will be able to access information through two web-based interfaces directed to physician and non-physician users respectively. Hospitals are connected through a virtual private network to exchange patient information and users need to obtain a private key from the certificate authority in order to securely connect to MIEC. A pilot project was conducted to demonstrate the feasibility of this architecture and the problems encountered were discussed.

A new technology for harnessing the dye polluted water and dye collection in a chemical factory

A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat-electric energy. It consists of four parts: (1) evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2) polluted water circulating system (pumping-spraying-collecting); (3) heating system; (4) workshop with polluted water reservoir-tanks and rainfall prevention roof. The polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind and air temperature energy). In case, when there is no roof for the carrier system, the polluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10-25 mm rainfall also need to be stored in the reservoirs to meet the state standard for discharging wastewater. The dye may be collected at the surface in the reservoir-tanks and the crystallized salt may be collected at the bottom plate. The black-color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non-pollution production of dye may be realized by using this technology with environmental, economical and social benefits.

Ectopic expression of negative ARNT2 factor disrupts fish development

ARNT factors are a cluster of bHLH-PAS factors that heterodimerize with other specific bHLH-PAS factors to mediate a wide range of biological responses. Previously, we obtained a truncated form of ARNT2-like factor, ARNT2A, from zebrafish, which encompasses the basic-helix-loop-helix and PAS A/B domains, but lacks a transactivation domain at its carboxyl end. Herein, we report another truncated ARNT2-like factor, ARNT2X, in zebrafish, which differs from ARNT2A at its N-terminal region. In cultured ZLE cells, transiently expressed ARNT2X and ARNT2A inhibited 2,3,7,8-TCDD-activated cyp1a1 transcription with different efficiencies. In the developing embryo, arnt2X mRNA was consistently expressed in the retinal and neural tube regions until the hatching stages, but it exhibited a more specific pattern at larval stages, including expression in the brain, eyes, hypothalamus, pharyngeal skeleton, heart, liver, pronephros duct, pectoral fin, and epithelial cells of the swim bladder. In contrast, arnt2A transcription diminished after hatching. Microinjecting a recombinant arnt2X-expression vector into fertilized eggs before cleavage stages caused severe defects in brain, eyes, pectoral fin, heart, and gut development. This suggests that the ARNT-mediated signal transduction pathways play important roles in fish tissue development.

High-performance liquid chromatographic analysis for the characterization of triterpenoids from Ganoderma

A high-performance liquid chromatographic (HPLC) analysis of triterpenoids from Ganoderma is developed and validated in an attempt to explore a way to differentiate a number of species of the genus Ganoderma. Results show that 64 samples examined in this study could be divided into 18 groups based on characteristics of the HPLC pattern of triterpenoids. This result also conforms with those of the morphological examination and the interfertility test by di-monokaryotic mating. The HPLC analysis of triterpenoids further reveals that differentiation among samples from three different regions each of the two species G. lucidum and G. tsugae is workable. Even then, an incorrect designation is found for two of the groups of samples that were originally classified as G. resinaceum but showed different morphological characteristics and mating incompatibility. In conclusion, an HPLC analysis of triterpenoids is a simple and easy way to differentiate among different species of the genus Ganoderma.

[Level change of IL-10, IL-12 and TNF alpha in the serun of patients with hepatocellular carcinoma]

OBJECTIVE

To study the relationship and clinical significance between level change of serum Interleukin 10 (IL-10), interleukin 12 (IL-12), tumor necrosis factor-alpha (TNF alpha) and primary hepatic carcinoma (PHC).

METHODS

Serum IL-10, IL-12, TNF alpha in 40 patients with PHC, 36 cases with hepatocirrhosis and 33 normal controls were measured with ELISA.

RESULTS

The higher serum levels of IL-10, IL-12, TNF alpha were observed in patients with hepatocirrhosis than in controls (P < 0.01), although IL-12, TNF alpha in the serum of patients with PHC were in the proximity of that of controls (P > 0.05), the IL-10 level was significantly higher than that of control (P < 0.01), further more, IL-10 being opposed to IL-12, TNF alpha is higher in patients with tumor above 5.0 cm in diameter than below 5.0 cm, IL-12 and TNF alpha were declined and IL-10 increased with tumor enlargement.

CONCLUSION

The immune dysfunction in patients with PHC may be related to level increase of IL-10. The level decrease of IL-12, TNF alpha and increase of IL-10 is helpful to clinical differential diagnoses between cirrhotic nodule and PHC, and this suggests cancerous tendency.

Acrokeratosis paraneoplastica (Bazex syndrome) with adenocarcinoma of the colon: report of a case and review of the literature

Acrokeratosis paraneoplastica is a rare disease and is uncommon even in patients with upper aerodigestive tract cancer. We report a 63-year-old man with a 1-month history of numerous pruritic lesions and vesicles on both feet. Although he had received local therapy, progressive dense scale formation involving both palms and both soles was found. Colonoscopy was performed because of hematochezia, and it revealed an early colon cancer. After the resection of the cancer, the skin lesions began to fall off dramatically. To the best of our knowledge, there is no report of acrokeratosis paraneoplastica associated with colon cancer in the literature. This is the first case report of acrokeratosis paraneoplastica associated with early colon cancer.

Overexpression of a Zebrafish ARNT2-like Factor Represses CYP1A Transcription in ZLE Cells

Aryl hydrocarbon receptor nuclear translocator (ARNT) factors belong to a novel basic-helix-loop-helix-PAS (bHLH-PAS) transcription factor family that controls a variety of physiological and developmental processes. In a previous study, we obtained a partial complementary DNA fragment of an ARNT2-like factor from zebrafish embryo, liver, and other tissues by reverse transcription-polymerase chain reaction. In an effort to characterize the function of this factor, we screened an embryonic complementary DNA library and obtained a complete cDNA of this ARNT2-like factor, zARNT2A. The deduced protein sequence of zARNT2A encompasses the basic-helix-loop-helix and PAS-A/B motifs and shares highest sequence similarity with the amino-terminal half of mouse ARNT2 factor. However, it lacks a carboxy-terminal transactivation motif following the PAS-A/B motifs. Transient expression of zARNT2A in cultured cells resulted in repression of TCDD-dependent CYP1A transcription. Whole-mount in situ hybridization revealed that zARNT2A is expressed in brain and pronephros at prime-5 stages. In adult fish, zARNT2A messenger RNA is transcribed in a wide range of tissues, which indicates that zARNT2A and its corresponding signal transduction mechanisms have important roles in fish development and other physiological aspects.

Characterization of acute myeloid leukemia with MLL rearrangements--no increase in the incidence of coexpression of lymphoid-associated antigens on leukemic blasts

MLL gene rearrangements are associated with coexpression of myeloid- and lymphoid-associated antigens on leukemic blasts and a dismal outcome in acute lymphoblastic leukemia (ALL). Whether the same conditions can apply to acute myeloid leukemia (AML) is not quite clear. Rearrangements of the MLL gene were analyzed on 113 patients with newly diagnosed de novo AML in a single institution. Sixteen (14%) of them showed rearranged bands by Southern blot analysis, including three (50%) of six infants, three (14%) of 21 children between 1 and 15 years and 10 (12%) of 86 adults. MLL rearrangements were not only detected in M5 (four of 12 patients, 33%) and M4 (six of 31, 19%) subtypes but also in other non-M4-M5 AML (six of 70, 9%), including M1, M2 and M7, but not M3 subtype. Seven patients had chromosomal abnormalities involving 11q23, but nine did not. The latter comprised three (6%) of 48 patients with normal karyotype, one with t(8;21), none with t(15;17), inv(16) or t(9;22), and four (15%) of 27 with cytogenetic aberrations other than those specific structural abnormalities. In contrast to ALL, AML patients with MLL rearrangements did not tend to coexpress lymphoid- and myeloid-associated antigens simultaneously on leukemic blasts and have similar outcome as those without the gene rearrangements.

Diagnosis of Penaeus monodon-type baculovirus by PCR and by ELISA of occlusion bodies

The black tiger prawn Penaeus monodon is a valuable aquaculture product in Taiwan. Two specific diagnostic methods were established for P. monodon-type baculovirus, one using polymerase chain reaction (PCR) technology and the other enzyme-linked immunosorbent assay (ELISA) technology. Monodon-type baculovirus (MBV) was purified by sucrose gradient centrifugation from occlusion bodies of MBV-infected postlarvae of P. monodon. MBV DNA was subsequently purified from the occlusion bodies and its presence was confirmed by PCR using primers of the polyhedrin gene. Based on conserved sequences of the DNA polymerase genes of Autographa californica nuclear polyhedrosis virus (AcMNPV) and Lymantria dispar nuclear polyhedrosis virus (LdMNPV), primers were designed and synthesized to yield a 714 bp PCR fragment from MBV. However, the sequence of this fragment revealed low homology with that of LdMNPV and AcMNPV. From the DNA sequence of this fragment, a second set of primers was designed, and using these primers, a 511 bp DNA fragment was amplified only when MBV DNA was the template. DNA templates from AcMNPV, white spot syndrome diseased shrimp, or PMO cells (a cell line derived from the Oka organ of Penaeus monodon) did not give any amplified DNA fragment. Therefore, this primer pair was specific for the diagnosis of MBV. By using intraspleenic immunization of rabbits with purified MBV occlusion bodies, a polyclonal rabbit antiserum against MBV was obtained. This antiserum could detect nanogram levels of MBV, but did not cross react with white spot syndrome virus (WSSV), homogenates of PMO cells, postlarvae, hepatopancreatic tissue or intestinal tissue of black tiger prawns by competitive ELISA. This sensitive method could detect MBV even in tissue homogenates.

Minimally differentiated acute myeloid leukemia in Taiwan: predominantly occurs in children less than 3 years and adults between 51 and 70 years

Acute myeloid leukemia (AML) with minimal differentiation was usually referred to as acute undifferentiated leukemia in the past. With the help of immunophenotyping, this subtype of leukemia was shown to express myeloid antigens on the blasts and was designated AML-M0 by FAB Cooperative Study Group in 1991. Among the 423 consecutive newly diagnosed de novo AML at our institution, 12 (2.8%) were of M0 subtype. The proportion of M0 in AML was higher in children than in adults (8.2% vs 1.7%). Four other M0 patients referred from outside hospitals for immunophenotyping were also included in this study. There were two peaks in age distribution of these 16 patients: less than 3 years and between 51 and 70 years, respectively. Organomegaly was more common in patients with AML-M0 than in those with other subtypes (56.3% vs 29.2%, P = 0.025). The former patients had higher incidences of CD7 and CD34 expression on the leukemic cells than the latter ones (50% vs 16.9%, P = 0.003 and 69.2% vs 37.9%, P = 0.019, respectively). The patients with AML-M0 showed more frequent clonal chromosomal abnormalities in the leukemic cells than other AML patients (83.3% vs 53.9%, P = 0.039); the same is also true for complex cytogenetic aberrations (50% vs 11. 4%, P = 0.004). Adults with AML-M0 showed a lower complete remission (CR) rate and significantly poorer survival than those with non M0-AML. However there was no significant difference in outcome between the two groups of pediatric patients. In conclusion, AML-M0 is a unique subtype of leukemia that has distinct age distribution and shows different clinical and biological characteristics from other AML. Adult patients have poor prognosis. Whether pediatric patients had better outcome than adults needs to be clarified in further studies.

Direct determination of isochromatic fringe order by use of two wavelengths

A method of direct determination of photoelastic fringe order is proposed. The relations between the integral fringe order for one wavelength and the fractional fringe orders of two wavelengths are derived. The exact fringe order of the whole field is automatically calculated. The usefulness of this method is demonstrated through experimental result.

Development of fungal mycelia as skin substitutes: effects on wound healing and fibroblast

In this study, Sacchachitin membrane, prepared from the residue of the fruiting body of Ganoderma tsugae, was estimated for its effects on wound healing and the proliferation and migration of fibroblast cells. Two mirror-image wounds were made on the back of female guinea pigs by dissecting a 1.5 x 1.5 cm2 skin surface of full thickness. Sacchachitin membrane was placed randomly on one of the wounds and gauze or Beschitin on the other. Changes in the wound area were measured and photographed after a predetermined amount of time postoperatively. Histological examination of the wound and surrounding tissue was also performed to reveal any interaction of tissue with the dressing. The results showed that the wound area covered with Sacchachitin membrane was statistically smaller than that covering with gauze on day 10, whereas there was no significant difference in the wound size compared to that with Beschitin. Fibroblast cells from the dermis layer of guinea pigs were used. The number of fibroblast cells were counted on the predetermined days in the culture suspended with or without 0.01% w/v dressing materials. By layering on DMEM plates, the number of fibroblast cells migrating across the center line or outside of the central hole were counted after five days. All the results indicated that both 0.01% w/v of Sacchachitin and chitin significantly enhanced the proliferation and migration of fibroblast cells.

The first high-mobility-group box of upstream binding factor assembles across-over DNA junction by basic residues

Upstream binding factor (UBF) is a eukaryotic RNA polymerase I-specific transcription factor. Its predominant DNA-binding motif, ubfHMG box 1, preserves DNA assembling activity that can bind two or more DNA duplexes simultaneously to form a crossover DNA junction. Here we investigate the basis of crossover DNA-assembling activity of ubfHMG box 1 by extensive mutagenesis analyses and mobility shift assay. Although the ubfHMG box 1 preserves a high mobility group (HMG) core structure, changing a number of the consensus hydrophobic and aromatic residues to alanine did not inhibit its crossover-assembling activity. This indicates that these residues do not directly participate in protein-DNA interaction. However, altering a series of basic residues in the helices 1 and 2 regions or the N-terminal extended strand of the ubfHMG box 1 motif had severe effects on DNA-assembling activity; however, certain non-specific DNA binding activity still remained. This suggests that the ubfHMG box 1 motif might extensively contact the backbone of a crossover junction through its multiple basic residues. Mutating a hydrophobic residue in the terminal dimerization domain inhibited the association of truncated Xenopus UBF, but had little effect on its crossover-assembling activity. This indicates that the UBF-crossover DNA complex is not established by the association of individual DNA-bound peptides.

Differential effects of heavy metals on the binding of Xenopus upstream binding factor(xUBF) to DNA

Xenopus upstream binding factor (xUBF) is a transcription factor for RNA polymerase I which contains multiple DNA-binding motifs. Among these DNA-binding motifs, HMG box I is essential for promoting RNA polymerase I-dependent rRNA gene transcription. Gel shift assay indicated that the binding of recombinant HMG box I to a 136-bp linear DNA probe was significantly inhibited by Cd2+ at 1 microM. The formation of larger protein-DNA complexes was particularly sensitive to Cd2+. The interaction between HMG box I and DNA was completely inhibited by 10 microM of Cd2+, yet this interaction was not inhibited by the same concentration of Ca2+. Hg2+ at 0.1 microM began to cause abnormal band shifting, and protein-DNA bands disappeared to the wells of a polyacrylamide gel in the presence of 10 microM of Hg2+, reflecting that a drastic change in the conformation of HMG box I-DNA had occurred. The binding of HMG box I to DNA was slightly disturbed by As3+ at 1 microM and was significantly affected at 10 microM. Our results suggest that inhibition of the normal binding of UBF to its target DNA may be one of the mechanisms of heavy metal-induced inhibition of RNA synthesis.

Fungal mycelia as the source of chitin and polysaccharides and their applications as skin substitutes

A wovenable skin substitute (Sacchachitin) made from the residue of the fruiting body of Ganoderma tsugae was developed in this study. Chemical analysis revealed that the treated residue was a copolymer of beta-1,3-glucan (ca 60%) and N-acetylglucosamine (ca 40%) with a filamental structure of mycelia form, as demonstrated by both optical and scanning electron microscopy. The pulp-like white residue was then woven into thin, porous sheets 7.0 cm in diameter and 0.1-0.2 mm in thickness by filtration and lyophilized for use as a skin substitute. The wound area produced by dissecting rat skin of full thickness was found to almost completely heal on the side covered with Sacchachitin, whereas the control side covered with cotton gauge was around 6.0 cm2 on the 28th day. Furthermore, the wound healing effects of the chitin sheet from crab shell (Beschitin) and Sacchachitin were not found to be significantly different.

Digital color encoding and its application to the moirétechnique

A moiré pattern color-encoding technique in which a digital image-processing system is used is described. The technique can display color moiré patterns with color sequences that represent the fringe orders. This technique is simple and fast and can be performed automatically. Experimental results demonstrating the feasibility of the technique are reported.

The mitochondria are recognition organelles of cell stress

The cellular response to stress includes synthesis of specific stress proteins in the presence of a generalized suppression of protein synthesis. The response occurs in intact animals, individually stressed organs of intact animals, donor organs upon removal, regardless of preservation methods, and cells in culture. The molecular biology of stress protein induction is not understood. While stress proteins are beneficial, overall suppression of protein synthesis, if prolonged, is harmful. Since altered energy metabolism is integral to stress induction, we examined the mitochondria to determine if they could provide a possible molecular mechanism for initiating the response. Rat myoblasts were incubated at varying temperatures for up to 120 min in [35 S] methionine. Proteins were separated electrophoretically and newly synthesized proteins visualized autoradiographically. Isolated mitochondria from resting rat myoblasts were then stressed, label incorporation determined, and newly synthesized protein was visualized. Stress sharply suppressed protein synthesis in mitochondria but autoradiograms of stressed mitochondria showed that a single stress protein of 18 kDa was synthesized. Mitochondria independently respond to stress and synthesize a stress protein from their own DNA. This protein may provide an intermediary pathway that links stressful conditions in the environment to the overall response observed in the cell.

The dimerization domain upstream binding factor contains multiple helical structures

The upstream binding factor, UBF, is an RNA polymerase I transcription factor which contains multiple DNA binding domains and a novel protein dimerization domain. Active UBF forms homodimers in vivo through the intramolecular interactions of its dimerization domain, which spans a hundred amino-terminal residues. In the presence of both UBF dimerization domain and its immediately adjacent lysine-rich basic DNA binding domain, the E. coli expressed recombinant polypeptide, dbUBF (dimerization plus basic motifs of UBF), forms homodimers in vitro and binds to double-stranded DNA nonselectively. In gel retardation assay, dbUBF dimers make multiple shift-ladders corresponding to numerous protein dimer-DNA complexes. The UBF dimerization domain contains multiple helical structures, as predicted by EMBO-PHD program. Most of hydrophobic residues in the dimerization domain are confined in the hydrophobic phase of these hypothetic helices. Mutating these hydrophobic residues to glutamate prohibits dbUBF association and gives a different shift pattern in gel retardation assay. The results we present here argue that UBF association is largely exerted by the hydrophobic interactions between the multiple helices to bring two molecules together.

Characterization of the 5'-flanking region of the gene for the gamma chain of human fibrinogen

The 5'-flanking region of the gene coding for the gamma chain of human fibrinogen was characterized for its promoter activity. Reporter gene studies using chloramphenicol acetyltransferase as the indicator along with mutations in the DNA showed that a TATA-like sequence (-20 to -23 base pairs (bp)), a CAAT-like sequence (-54 to -57 bp), and an upstream stimulatory factor (USF) binding site (-66 to -77 bp) constitute a minimal promoter that mediates liver-specific expression of the gene. Electrophoretic gel mobility assays and antibody binding studies confirmed the interaction of USF with the binding site. An IL-6 responsive element with a sequence of CTGGAA located at -301 to -306 bp was shown to be a functional element in the IL-6 response. In contrast to the IL-6 responsive elements in the human alpha- and beta-fibrinogen genes, the element in the gene for the gamma chain of human fibrinogen was unaffected by the presence or elevated levels of the beta or delta isoforms of the CCAAT/enhancer binding proteins. A negative element with sequence homology to several silencer elements was also identified in the region of -348 to -390 bp of the gene for the gamma chain of human fibrinogen. A comparison of the regulatory elements in the genes coding for all three chains in fibrinogen is also presented.

Characterization of the 5'-flanking region of the gene for the alpha chain of human fibrinogen

The 5'-flanking region of the gene coding for the alpha chain of human fibrinogen was isolated, sequenced, and characterized. The principal site of transcription initiation was determined by primer extension analysis and the RNase protection assay and shown to be at an adenine residue located 55 nucleotides upstream from the initiator methionine codon, or 13,399 nucleotides down-stream from the polyadenylation site of the gene coding for the gamma chain. Transient expression of constructs containing sequentially deleted 5'-flanking sequences of the alpha chain gene fused to the chloramphenicol acetyltransferase reporter gene showed that the promoter was liver-specific and inducible by interleukin 6 (IL-6). The shortest DNA fragment with significant promoter activity and full response to IL-6 stimulation encompassed the region from -217 to +1 base pairs (bp). Although six potential IL-6 responsive sequences homologous to the type II IL-6 responsive element were present, a single sequence of CTGGGA localized from -122 to -127 bp was shown to be a functional element in IL-6 induction. A hepatocyte nuclear factor 1 (HNF-1) binding site, present from -47 to -59 bp, in combination with other upstream elements, was essential for liver-specific expression of the gene. A functional CCAAT/enhancer binding protein site (C/EBP, -134 to -142 bp) was also identified within 217 bp from the transcription initiation site. An additional positive element (-1393 to -1133 bp) and a negative element (-1133 to -749 bp) were also found in the upstream region of the alpha-fibrinogen gene.

Searching for bone fractures: a comparison with pulmonary nodule search

RATIONALE AND OBJECTIVES

We aimed to determine if the characteristics and principles of visual search described for the detection of pulmonary nodules apply to extremity fractures.

METHODS

The eye positions of staff orthopedic radiologists, radiology residents, and medical students were monitored as they searched hand and wrist X-ray images for fractures and a chest image for nodules.

RESULTS

More systematic scanning patterns were observed for experienced observers than inexperienced observers. Positive decisions for bone images were associated with prolonged gaze durations; prolonged gaze durations were significantly longer for false-negative versus true-negative decisions. Intercluster jump distances were found to be greater for chest images than bone images.

CONCLUSIONS

A search for bone fractures can be qualitatively characterized by classifying observer scan paths, dwell times, and jump distances. Gaze duration can be a useful predictor of bone image locations containing potential missed fractures. Perceptual feedback could aid observers in the detection of inconspicuous fractures.

xUBF, an RNA polymerase I transcription factor, binds crossover DNA with low sequence specificity

Xenopus UBF (xUBF) is a transcription factor for RNA polymerase I which contains multiple DNA-binding motifs. These include a short basic region adjacent to a dimer motif plus five high-mobility-group (HMG) boxes. All of these DNA-binding motifs exhibit low sequence specificity, whether assayed singly or together. In contrast, the HMG boxes recognize DNA structure that is formed when two double helices are crossed over each other. HMG box 1, in particular, requires association of two double helices before it will bind and, either by itself or in the context of the intact protein, will loop DNA and organize it into higher-order structures. We discuss how this mode of binding affects the function of xUBF as a transcription factor.

Caterpillar bodies: distinctive, basement membrane-containing structures in blisters of porphyria

In a previous study, we reported on the observation of a relatively specific, linear body in the roofs of bullae from cases of porphyria cutanea tarda. In the present study, we expand on these observations to show the presence of these bodies in lesions of pseudoporphyria cutanea tarda and erythropoietic protoporphyria. Furthermore, we have applied immunoperoxidase techniques using antibodies to type IV collagen and laminin to show that they are composed of basement membrane material. Because the segmented, elongated shapes of these bodies reminded us of the larvae of butterflies, we coined the term "caterpillar bodies" to describe them. These bodies are similar in their composition to the Kamino bodies of Spitz's nevi, cylindrical bodies in adenoid cystic carcinoma, Civatte bodies of lichen planus, and the collagenous spherules seen in a number of conditions, and may provide a unique clue to the diagnosis of the porphyric bullous eruptions.