Biological response of protists Haematococcus lacustris and Euglena gracilis to conductive polymer poly (3,4-ethylenedioxythiophene) polystyrene sulfonate.

Improving the growth and pigment accumulation of microalgae by electrochemical approaches was considered a novel and promising method. In this research, we investigated the effect of conductive polymer poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) dispersible in water on growth and pigment accumulation of Haematococcus lacustris and Euglena gracilis. The results revealed that effect of PEDOT:PSS was strongly cell-dependent and each cell type has its own peculiar response. For H. lacustris, the cell density in the 50 mg·l-1 treatment group increased by 50·27%, and the astaxanthin yield in the 10 mg·l-1 treatment group increased by 37·08%. However, under the high concentrations of PEDOT:PSS treatment, cell growth was significantly inhibited, and meanwhile, the smaller and more active zoospores were observed, which reflected the changes in cell life cycle and growth mode. Cell growth of E. gracilis in all the PEDOT:PSS treatment groups were notably inhibited. Chlorophyll a content in E. gracilis decreased while chlorophyll b content increased in response to the PEDOT:PSS treatment. The results laid a foundation for further development of electrochemical methods to promote microalgae growth and explore the interactions between conductive polymers and microalgae cells.

Crossbow injury to the neck.

Crossbow injuries are uncommon among penetrating trauma. The tendency for a crossbow bolt to remain in situ appears to limit catastrophic haemorrhage despite the involvement of major vessels.1 Here we report our experience with an injury to the left internal jugular vein by a crossbow bolt. The injury was successfully treated by emergency neck exploration.

Role of aquaporin-5 in gallbladder carcinoma.

BACKGROUND/PURPOSE: Aquaporins (AQPs) are important in controlling bile formation. However, the exact role in human gallbladder carcinogenesis has not yet been defined. METHODS: AQP-5-expressing gallbladder carcinoma (GBC) cell lines (NOZ) were transfected with anti-AQP-5 small interfering RNA (siRNA). Growth, migration, invasion assay, and drug susceptibility tests were performed. Next, microRNA (miRNA) expression was analyzed by miRNA oligo chip (3D-Gene®). AQP-5 and AQP-5-related miRNA target gene expressions were also analyzed using tissue microarray (TMA) in 44 GBC samples. RESULTS: Treatment with AQP-5 siRNA decreased cell proliferation, migration, and invasion. On the other hand, those cells increased IC50 of gemcitabine. By performing miRNA assays, miR-29b, -200a, and -21 were shown to be highly overexpressed in cells treated with AQP-5 siRNA NOZ. When focusing on miR-21, phosphatase and tensin homolog (PTEN) was found to be a target of miR-21. In the TMA, AQP-5/PTEN coexpression was significantly associated with the depth of invasion and MIB-1 index (p = 0.003, 0.010). Survival of patients with a high AQP-5/PTEN coexpression was longer than that of patients with a low coexpression (p = 0.003). CONCLUSIONS: Our result suggested that miR-21 and PTEN may contribute to the role of AQP-5 in GBC. AQP-5 and PTEN cascades are favorable biomarkers of GBC.

Monosaccharide composition of the outer membrane lipopolysaccharide and O-chain from the freshwater cyanobacterium Microcystis aeruginosa NIES-87.

AIMS: Bacterial lipopolysaccharide (LPS) protruding from the outermost layer of the outer membrane is expected to play an important role in cell physiology by interacting with molecules in the extracellular milieu; however, the structural and functional characteristics of these components in cyanobacteria remain largely unknown. We isolated water-soluble fractions of LPS and O-chain from the bloom-forming freshwater cyanobacterium Microcystis aeruginosa NIES-87 and identified their monosaccharide compositions. METHODS AND RESULTS: SDS-PAGE followed by silver staining demonstrated that the isolated total LPS was the smooth type with different numbers of repeating sugar units in the O-chain region. GC/MS analysis after acid hydrolysis, reduction and acetylation treatments indicated that the neutral monosaccharide components of the total LPS include glucose, rhamnose, mannose, galactose and xylose (in decreasing order of weight percentage), while only glucose was detected in the purified O-chain fraction. MALDI-TOF MS analysis suggested that the O-chain fraction is composed of repeating glucose and methylated glucose disaccharide units. CONCLUSIONS: Our results indicate that the monosaccharide composition of M. aeruginosa O-chain is relatively simple. SIGNIFICANCE AND IMPACT OF THE STUDY: Although further studies are necessary, these findings provide fundamental information for understanding the structural and functional properties of cyanobacterial LPS and O-chain.

A single amino acid substitution in the 126-kDa protein of pepper mild mottle virus controls replication and systemic movement into upper non-inoculated leaves of bell pepper plants.

Previously, we generated attenuated variants of pepper mild mottle virus by replacing residue 649 in the 126-kDa replicase protein with various amino acids. Here, we examined the biological properties of the 16 variants that caused either mild mosaic or no mosaic. All but one (A649N) of the mild-mosaic-inducing strains replicated at higher levels in pepper plants and systemically moved at higher rates into the upper non-inoculated leaves than the no-mosaic strains. C1421, previously selected for practical use, not only caused mild symptoms but also had an especially high replication rate in pepper plants and spread more efficiently into the upper non-inoculated leaves.

Effect of light on iron uptake by the freshwater cyanobacterium Microcystis aeruginosa.

Visible light was observed to induce reductive dissociation of organically complexed Fe and dramatically increase the short-term uptake rate of radiolabeled Fe by Microcystis aeruginosa PCC7806 in Fraquil* medium buffered by a single metal chelator, ethylenediaminetetraacetic acid (EDTA). Only wavelengths <500 nm activated Fe uptake indicating that Fe photochemistry rather than biological factors is responsible for the facilitated uptake. The measured rate of photochemical Fe(II) production combined with a significant decrease in (55)Fe uptake rate in the presence of ferrozine (a strong ferrous iron chelator) confirmed that photogenerated unchelated Fe(II) was the major form of Fe taken up by M. aeruginosa under the conditions examined. Mathematical modeling based on unchelated Fe(II) uptake by concentration gradient dependent passive diffusion of Fe(II) through nonspecific transmembrane channels (porins) could account for the magnitude of Fe uptake and a variety of other observations such as the effect of competing ligands on Fe uptake. Steady-state uptake rates indicated that M. aeruginosa acquires Fe predominantly during the light cycle. This study confirms that Fe photochemistry has a dominant impact on Fe acquisition and growth by M. aeruginosa in EDTA-buffered culture medium.

Norovirus-binding proteins recovered from activated sludge micro-organisms with an affinity to a noroviral capsid peptide.

AIMS: Transmission routes of noroviruses, leading aetiological agents of acute gastroenteritis, are rarely verified when outbreaks occur. Because the destination of norovirus particles being firmly captured by micro-organisms could be totally different from that of those particles moving freely, micro-organisms with natural affinity ligands such as virus-binding proteins would affect the fate of viruses in environment, if such microbial affinity ligands exist. The aim of this study is to identify norovirus-binding proteins (NoVBPs) that are presumably working as natural ligands for norovirus particles in water environments. METHODS AND RESULTS: NoVBPs were recovered from activated sludge micro-organisms by an affinity chromatography technique in which a capsid peptide of norovirus genogroup II (GII) was immobilized. The recovered NoVBPs bind to norovirus-like particles (NoVLPs) of norovirus GII, and this adsorption was stronger than that to NoVLPs of norovirus genogroup I. The profile of two-dimensional electrophoresis of NoVBPs showed that the recovered NoVBPs included at least seven spots of protein. The determination of N-terminal amino acid sequences of these NoVBPs revealed that hydrophobic interactions could contribute to the adsorption between NoVBPs and norovirus particles. CONCLUSIONS: NoVBPs conferring a high affinity to norovirus GII were successfully isolated from activated sludge micro-organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: NoVBPs could be natural viral ligands and play an important role in the NoV transmission.

Cytoplasmic chaperones in precursor targeting to mitochondria: the role of MSF and hsp 70.

Despite extensive study since the early 1980s, the mechanism by which newly synthesized protein precursors are unfolded in the cytoplasm and targeted correctly to the mitochondrial surface prior to translocation through the mitochondrial membranes is understood poorly. Recently, an N-ethylmaleimide (NEM)-sensitive cytoplasmic factor called mitochondrial import stimulation factor (MSF), which catalyses the ATP-dependent unfolding of precursor proteins, was described. Unlike the more general chaperone proteins of the hsp70 families, MSF not only unfolds proteins but also targets the unfolded precursor proteins to the mitochondria. Here, Mihara and Omura summarize what is known about MSF and speculate on how it, and other cytoplasmic factors, may be involved in mitochondrial import.

Immunochemical and immunoelectron microscope studies on localization of NADPH-cytochrome c reductase on rat liver microsomes.

By the use of ferritin-conjugated antibody (conjugate) indirect immunoelectron microscopy, NADPH-cytochrome c reductase was localized on rat liver microsomes. Most microsomes in the sections had from 1 to 12 conjugates on their outer surfaces. Among the conjugates, 83% was estimated to bind to NADPH-cytochrome c reductase at a molecular ratio of 1:1, 12% at the ratio of 2:1, and 5% at the ratio of 3 or 4:1. The correlation between immunochemical and morphological data confirmed that most of the NADPH-cytochrome c reducatase reacted with the conjugates. Subsequent morphological analyses have revealed that the enzyme is distributed homogeneously on the outer surfaces of microsomes but heterogeneously within microsomes in groups of three to five enzyme molecules.

A single residue in the 126-kDa protein of pepper mild mottle virus controls the severity of symptoms on infected green bell pepper plants.

Infectious cDNA clones originally derived from a mild strain of Pepper mild mottle virus were constructed by replacing residue 649, a critical point for attenuation of this virus, with all possible amino acids. All clones were infectious to pepper plants and induced a variety of symptoms, including no visible symptoms. The results of this study showed that a single amino acid mutation at residue 649 could control the function of the 126- and 183-kDa proteins, replicases with multiple roles in the life cycle of this virus.

Restoration of shoulder function and elbow flexion by nerve transfer for poliomyelitis-like paralysis caused by enterovirus 71 infection.

We report the case of an eight-month-old girl who presented with a poliomyelitis-like paralysis in her left upper limb caused by enterovirus 71 infection. She recovered useful function after nerve transfers performed six months after the onset of paralysis. Early neurotisation can be used successfully in the treatment of poliomyelitis-like paralysis in children.

The relationship between pre-operative symptoms, operative findings and postoperative complications in schwannomas.

This study presents a retrospective review of the management of schwannomas in the limbs and examines the relationship between pre-operative clinical examination, operative findings and postoperative neurological complications. Eighteen tumours with a histological diagnosis of schwannoma in 17 patients who underwent surgery between 1998 and 2004 were the basis of this study. Enucleation of the tumour was possible in 14 cases. None of these patients had neurological complications pre-operatively but eight had mild neurological complications postoperatively. The complications consisted of sensory deficit in five cases, motor weakness in one and both in two. Enucleation of the tumours was impossible in four cases. These schwannomas originated in the brachial plexus in three cases and the ulnar nerve in the proximal arm in one case. Tumours with pre-operative symptoms and masses located at a proximal site in the limb were more likely to be impossible to enucleate completely.

Heavy metal-binding proteins from metal-stimulated bacteria as a novel adsorbent for metal removal technology.

Water pollution with toxic heavy metals is of growing concern because heavy metals could bring about serious problems for not only ecosystems in the water environment but also human health. Some metal removal technologies have been in practical use, but much energy and troublesome treatments for chemical wastes are required to operate these conventional technologies. In this study, heavy metal-binding proteins (HMBPs) were obtained from metal-stimulated activated sludge culture with affinity chromatography using copper ion as a ligand. Two-dimensional electrophoresis revealed that a number of proteins in activated sludge culture were recovered as HMBPs for copper ion. N-termini of five HMBPs were determined, and two of them were found to be newly discovered proteins for which no amino acid sequences in protein databases were retrieved at more than 80% identities. Metal-coordinating amino acids occupied 38% of residues in one of the N-terminal sequences of the newly discovered HMBPs. Since these HMBPs were expected to be stable under conditions of water and wastewater treatments, it would be possible to utilize HMBPs as novel adsorbents for heavy metal removal if mass volume of HMBPs can be obtained with protein cloning techniques.

Membrane separation of indigenous noroviruses from sewage sludge and treated wastewater.

In this study, feasibility of membrane separation for the removal of indigenous noroviruses (NVs) is evaluated. The indigenous NV gene was never detected from ultrafiltration (UF) permeates of sewage sludge and treated wastewater. Indigenous NV gene was also not detected from permeates of sewage sludge and treated wastewater by microfiltration (MF) with a pore size of 0.1 microm (MF0.1). Even though the pore size of MF (0.1 microm) was much larger than the diameter of virus particle (approximately 30-40nm), more than 4-log10 reduction value (LRV) at maximum was achieved by membrane separation with MF0.1. NV genes were often detected from permeates of sewage sludge and treated wastewater by MF with a pore size of 0.45 microm (MF0.45), although the maximum log10 reduction values were more than 3.59 for sewage sludge and more than 2.90 for treated wastewater. It is important to verify factors determining the removal efficiency of viruses with MF membranes.

Crystallization and preliminary X-ray study of a double-shelled spherical virus, rice dwarf virus.

Rice dwarf virus (RDV) is a double-shelled spherical plant virus consisting of 46,000 Mr capsid and 114,000 Mr core proteins and minor structural proteins, and containing 12 genome segments of double-stranded RNA. The virus has been crystallized in the cubic space group I23 with a = 789 A. There are two particles per unit cell, each positioned on a point of 23 symmetry. Packing considerations showed that the diameter of the virus particle is 693 A. The crystals diffract to at least 6.5 A resolution.

Genetic Control of Meiosis in Rice, ORYZA SATIVA L. III. Effect of DS Genes on Genetic Recombination.

The recombination frequency as influenced by five independent recessive ds genes was measured on three segments of different chromosomes of rice, Oryza sativa L. Each ds gene in the homozygous condition resulted in an almost equally reduced recombination frequency in the three segments. When the mean reduction in recombination frequency was related to the reduction of chiasma frequency, the five ds genes were divided into two types: in one type the reduction of chiasma frequency almost corresponded to the mean reduction of recombination frequency, and in the other the chiasma frequency was greatly reduced in comparison with the mean reduction of recombination frequency. Three of the five ds genes were found to belong to the former group. In both types, normal synaptonemal complexes were observed in pachytene cells homozygous for ds genes. This finding suggests that ds genes do not affect the formation of synaptonemal complexes which are regarded as the prerequisite structure for crossing over.

Activation of CYP11A and CYP11B gene promoters by the steroidogenic cell-specific transcription factor, Ad4BP.

We have examined the transcriptional activity of four cis-elements, Ad1(CRE), Ad2, Ad3, and Ad4, that are present in the promoter of the bovine CYP11B (11 beta-hydroxylase P-450) gene using beta-globin reporter gene constructs and transient transfection into steroidogenic and nonsteroidogenic cell types. Only Ad1(CRE), a CRE homolog, showed forskolin-dependent transcriptional activity in adrenal tumor Y-1 cells, whereas the other elements were not able to stimulate transcription by themselves. As Ad3 and Ad4 had previously been identified as the cis-elements required for full cAMP-dependent transcription of this gene, we examined the effect of combinations of different cis-elements on the transcription of the reporter gene. In Y-1 cells, Ad1(CRE) and four tandem copies of any one of the other cis-elements substantially activated transcription in response to forskolin treatment. The template carrying Ad1(CRE) and Ad4 was also active in testicular Leydig cells, I-10, whereas it was inactive in nonsteroidogenic PC-12 cells. Transcriptional activation by the 4xAd4/Ad1(CRE) combination presumably depended on the presence of Ad4-binding protein (Ad4BP), which is absent in PC-12 cells, as shown by immunoblot analysis. This was confirmed by cotransfecting an expression vector for Ad4BP into PC-12 cells, which caused forskolin-dependent transcription to increase in proportion to the amount of expression vector. In Y-1 cells, transcriptional activation by forskolin was mimicked by cotransfection of an expression vector for the catalytic subunit of protein kinase-A.(ABSTRACT TRUNCATED AT 250 WORDS)

Gentian mosaic virus: A New Species in the Genus Fabavirus.

ABSTRACT A viral isolate, designated N-1 and obtained from a gentian (Gentiana scabra) plant that exhibited mosaic symptoms, was transmitted mechanically to nine plant species in six families. These plants are known as hosts of fabaviruses. The N-1 isolate was composed of isometric particles 30 nm in diameter and included two RNA molecules of approximately 6.0 and 3.6 kb in length, as estimated by agarose gel electrophoresis. The RNAs were encapsidated separately in two of the three types of particle. Each particle contained two distinct proteins with Mr values of 39.3 x 10(3) and 26.6 x 10(3), as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Analysis of complete nucleotide sequences of the RNAs suggested that each encoded a single large polyprotein, in which putative functional proteins were arranged in a manner similar to those in Broad bean wilt virus 1 (BBWV-1) and Broad bean wilt virus 2 (BBWV-2), which are members of the genus Fabavirus (family Comoviridae). Analysis of the deduced amino acid sequences of the proteins indicated that those of isolate N-1 shared 38 to 66% identity with those of BBWV-1 and BBWV-2 but only 16 to 42% identity with those of a comovirus, Cowpea mosaic virus. Phylogenetic analysis, based on the amino acid sequences of RNA polymerase, placed isolate N-1 in a separate lineage from BBWV-1 and BBWV-2. In indirect-enzyme-linked immunosorbent assay, isolate N-1 exhibited distant serological relationship to BBWV-1, BBWV-2, and Lamium mild mosaic virus, another fabavirus. Our results suggest that N-1 represents a new species of Fabavirus. We propose the name Gentian mosaic virus for this new species.

Transforming growth factor beta 1 and extracellular matrix gene expression in isoprenaline induced cardiac hypertrophy: effects of inhibition of the renin-angiotensin system.

OBJECTIVE: The aim was to investigate changes in cardiac transforming growth factor beta 1 (TGF-beta 1), fibronectin, and collagen types I and III mRNA levels in isoprenaline induced cardiac hypertrophy, and the effects of delapril, an angiotensin converting enzyme inhibitor, and TCV-116, an angiotensin II type 1 receptor antagonist, on this hypertrophy. METHODS: Rats were continuously infused with saline and low or high dose of isoprenaline (0.5 or 3 mg.kg-1.d-1) by an osmotic minipump for 24 h, 48 h or 7 d. Treatment with delapril (100 mg.kg-1.d-1) or TCV-116 (10 mg.kg-1.d-1) was started from 1 d before the implantation of minipump to the end of experiments. After the experimental periods, left ventricular weight was measured and the mRNA was extracted and measured by northern blot hybridisation. RESULTS: Both low and high doses of isoprenaline infusion resulted in increased left ventricular weight. With low dose infusion, cardiac TGF-beta 1 mRNA was not stimulated throughout the infusion, while fibronectin mRNA and collagen types I and III mRNAs began to increase at 24 h and 48 h, respectively, after the infusion. In high dose isoprenaline infusion, not only was extracellular matrix mRNA but also TGF-beta 1 mRNA in the ventricle significantly increased. TCV-116 prevented isoprenaline induced left ventricular hypertrophy as much as delapril. However, with delapril or TCV-116, the time course of TGF-beta 1 and ECM mRNA expression was almost similar to isoprenaline infusion only. CONCLUSIONS: The extracellular matrix mRNA expressions are enhanced in myocardial hypertrophy by a low dose of isoprenaline, which is probably not mediated by TGF-beta 1. The preventive effects of TCV-116 on this hypertrophy indicate that the inhibitory effects of angiotensin converting enzyme inhibitor on cardiac hypertrophy are due to the inhibition of angiotensin II and that angiotensin II type I receptor plays an important role in isoprenaline induced left ventricular hypertrophy. However, the renin-angiotensin system may play a minor role in isoprenaline induced cardiac fibrosis.

Long acting calcium antagonist amlodipine prevents left ventricular remodeling after myocardial infarction in rats.

OBJECTIVE: The purpose of this study was to examine the effect of amlodipine, a long-acting calcium antagonist, on the left ventricular remodeling, including systolic and diastolic dysfunction, the change of cardiac gene expression in the myocardial infarcted rats (MI). METHODS: On the first day after myocardial infarction, the animals were randomly assigned to amlodipine treatment (n = 8) or untreated groups (MI; n = 9). We then performed Doppler-echocardiographic examinations and measured the hemodynamics at four weeks after myocardial infarction. Following these measurements, their cardiac mRNA was analyzed. RESULTS: Left ventricular end-diastolic pressure (LVEDP) and central venous pressure (CVP) increased to 22 +/- 1 mmHg and 5 +/- 1 mmHg. Amlodipine reduced LVEDP and CVP to 15 +/- 1 mmHg (P < 0.01) and 3 +/- 0 mmHg (P < 0.01). The weight of right ventricle in MI was significantly larger than in the control rats (Control; 0.48 +/- 0.01 g/kg, MI; 0.79 +/- 0.04 g/kg, P < 0.01). Left ventricular end-diastolic dimension (LVDd) in MI increased to 10.3 +/- 0.3 mm (P < 0.01) (Control; 6.2 +/- 0.3 mm). Amlodipine prevented an increase of the weight of right ventricle (0.62 +/- 0.03 g/kg, P < 0.01) and LVDd (7.9 +/- 0.2 mm, P < 0.01 to MI). The rats in MI showed systolic dysfunction shown by the decreased fractional shortening (Control; 31 +/- 2% versus MI; 15 +/- 1%, P < 0.01), and diastolic dysfunction shown by E wave deceleration rate (Control; 18.1 +/- 2.0 m/s2, MI; 32.6 +/- 2.1 m/s2, P < 0.01). Amlodipine significantly prevented systolic and diastolic dysfunction. The increases in beta-MHC, alpha-skeletal actin, and ANP mRNAs in the non-infarcted left ventricle and right ventricle at four weeks after the myocardial infarction were all significantly suppressed by the treatment with amlodipine. On the other hand, depressed alpha-MHC was restored to normal levels by amlodipine in both regions. CONCLUSIONS: Amlodipine prevents the left ventricular remodeling process accompanied by systolic and diastolic dysfunction, and inhibits abnormal cardiac gene expression after myocardial infarction.