bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid endocytosis of a G protein-coupled receptor: substance P evoked internalization of its receptor in the rat striatum in vivo.
Authors: Mantyh P W , Allen C J , Ghilardi J R , Rogers S D , Mantyh C R , Liu H , Basbaum A I , Vigna S R , Maggio J E
Published: May 2006

Studies on cultured cells have shown that agonists induce several types of G protein-coupled receptors to undergo internalization. We have investigated this phenomenon in rat striatum, using substance P (SP)-induced internalization of the SP receptor (SPR) as our model system. Within 1 min of a unilateral striatal injection of SP in the anesthetized rat, nearly 60% of the SPR-immunoreactive neurons within the injection zone display massive internalization of the SPR--i.e., 20-200 SPR+ endosomes per cell body. Within the dendrites the SPR undergoes a striking translocation from the plasma membrane to endosomes, and these dendrites also undergo a morphological reorganization, changing from a structure of rather uniform diameter to one characterized by large, swollen varicosities connected by thin fibers. In both cell bodies and dendrites the number of SPR+ endosomes returns to baseline within 60 min of SP injection. The number of neurons displaying substantial endosomal SPR internalization is dependent on the concentration of injected SP, and the SP-induced SPR internalization is inhibited by the nonpeptide neurokinin 1 receptor antagonist RP-67,580. These data demonstrate that in the central nervous system in vivo, SP induces a rapid and widespread SPR internalization in the cell bodies and dendrites and a structural reorganization of the dendrites. These results suggest that many of the observations that have been made on the internalization and recycling of G protein-coupled receptors in in vitro transfected cell systems are applicable to similar events that occur in the mammalian central nervous system in vivo.
Distinct functions of SR proteins in recruitment of U1 small nuclear ribonucleoprotein to alternative 5' splice sites.
Authors: Zahler A M , Roth M B
Published: May 2006

Alternative splicing of precursor messenger RNAs (pre-mRNAs) is an important mechanism for the regulation of gene expression. The members of the SR protein family of pre-mRNA splicing factors have distinct functions in promoting alternative splice site usage. Here we show that SR proteins are required for the first step of spliceosome assembly, interaction of the U1 small nuclear ribonucleoprotein complex (U1 snRNP) with the 5' splice site of the pre-mRNA. Further, we find that individual SR proteins have distinct abilities to promote interaction of U1 snRNP with alternative 5' splice junctions. These results suggest that SR proteins direct 5' splice site selection by regulation of U1 snRNP assembly onto the pre-mRNA.
A chemically diverse conducting polymer-based "electronic nose".
Authors: Freund M S , Lewis N S
Published: May 2006

We describe a method for generating a variety of chemically diverse broadly responsive low-power vapor sensors. The chemical polymerization of pyrrole in the presence of plasticizers has yielded conducting organic polymer films whose resistivities are sensitive to the identity and concentration of various vapors in air. An array of such sensing elements produced a chemically reversible diagnostic pattern of electrical resistance changes upon exposure to different odorants. Principal component analysis has demonstrated that such sensors can identify and quantify different airborne organic solvents and can yield information on the components of gas mixtures.
Membrane-type matrix metalloproteinase (MT-MMP) gene is expressed in stromal cells of human colon, breast, and head and neck carcinomas.
Authors: Okada A , Bellocq J P , Rouyer N , Chenard M P , Rio M C , Chambon P , Basset P
Published: May 2006

From breast cancer cDNA libraries, we have cloned cDNAs that proved to correspond to the membrane-type matrix metalloproteinase (MT-MMP) recently identified in human placenta and proposed to be an activator of progelatinase A [Sato, H., Takino, T., Okada, Y., Cao, J., Shinagawa, A., Yamamoto, E. & Seiki, M. (1994) Nature (London) 370, 61-65]. Using one of these cDNAs as a probe, we have detected MT-MMP gene expression in all 83 human carcinoma specimens examined by RNA in situ hybridization and have found MT-MMP transcripts in fibroblastic cells of tumor stroma but not in cancer cells. Comparison with other MMP genes expressed in fibroblastic cells of human carcinomas indicated that the expression pattern of the MT-MMP gene was more closely related to that of the gelatinase A gene than to those of the stromelysin 3 or interstitial collagenase genes. These observations are consistent with the hypothesis that MT-MMP and gelatinase A are cooperating during tumor progression and strengthen the concept that proteolytic activities originating from the stromal component of human carcinomas have a critical role in tumor progression.
Genetic control of blood pressure and the angiotensinogen locus.
Authors: Kim H S , Krege J H , Kluckman K D , Hagaman J R , Hodgin J B , Best C F , Jennette J C , Coffman T M , Maeda N , Smithies O
Published: May 2006

Variants of the human angiotensinogen gene have been linked in some studies to increased circulating angiotensinogen levels and essential hypertension. To test for direct causality between genotypes at the angiotensinogen locus and blood pressures, we have studied mice carrying zero, one, two, three, or four functional copies of the murine wild-type angiotensinogen gene (Agt) at its normal chromosomal location. Plasma angiotensinogen levels increase progressively, although not linearly, from zero in the zero-copy animals to 145% of normal in the four-copy animals. Mice of all genotypes are normal at birth, but most zero-copy animals die before weaning. The kidneys of the zero-copy animals show pathological changes as adults, but the kidneys are normal in the other genotypes. One adult zero-copy male tested was fertile. The blood pressures of the one-copy through four-copy animals show significant and almost linear increases of approximately 8 mmHg per gene copy despite their normal compensatory mechanisms being intact. These results establish a direct causal relationship between Agt genotypes and blood pressures.
Opposite effects of transforming growth factor alpha and epidermal growth factor on mouse placental lactogen I secretion.
Authors: Yamaguchi M , Ogren L , Kurachi H , Hirota K , Imai T , Talamantes F
Published: May 2006

This study was undertaken to determine whether transforming growth factor alpha (TGF-alpha) regulates the production of mouse placental lactogen I (mPL-I) and mPL-II in a manner that is similar to that of epidermal growth factor (EGF), which was previously shown to stimulate mPL-I secretion and inhibit mPL-II secretion. In contrast to the activity of EGF, human (h) and rat (r) TGF-alpha (each at 100 ng/ml) inhibited secretion of mPL-I by placental cells isolated from mice on day 7 of pregnancy. Maximum inhibition of mPL-I secretion occurred on the third day of a 5-day culture period and ranged between 37% and 56% in multiple trials. Incubation of cells with hTGF-alpha and EGF was not followed by a change in the mPL-I concentration of the medium, suggesting the peptides antagonized each other's effects. hTGF-alpha and rTGF-alpha inhibited secretion of mPL-II; maximum inhibition ranged between 62% and 84% in multiple trials. The lowest concentrations of hTGF-alpha that affected mPL-I and mPL-II secretion were 10 ng/ml and 1 ng/ml, respectively. EGF and hTGF-alpha bound to the same receptors on placental cells, as assessed by cross-linking, and both peptides stimulated receptor phosphorylation, as assessed by Western blot analysis. There are three types of mPL-containing cells in placental cultures: cells that contain only mPL-I, cells that contain only mPL-II, and cells that contain both mPLs. The percentage of each type of mPL-containing cell in the culture was determined by immunostaining. hTGF-alpha affected the differentiation of the subpopulations of PL-containing cells in a manner that differed from that of EGF. The data suggest that TGF-alpha and EGF do not regulate the production of mPL-I and mPL-II in a similar manner.
Requirement for a phospholipase C in odor response: overlap between olfaction and vision in Drosophila.
Authors: Riesgo-Escovar J , Raha D , Carlson J R
Published: May 2006

A central problem in sensory system biology is the identification of the signal transduction pathways used in different sensory modalities. Genetic analysis of transduction mutants provides a means of studying in vivo the contributions of different pathways. This report shows that odorant response in one olfactory organ of Drosophila melanogaster depends on the norpA phospholipase C (EC 3.1.4.3) gene, providing evidence for use of the inositol 1,4,5-trisphosphate (IP3) signal transduction pathway. Since the norpA gene is also essential to phototransduction, this work demonstrates overlap in the genetic and molecular underpinnings of vision and olfaction. Genetic and molecular data also indicate that some olfactory information flows through a pathway which does not depend on norpA.
Delivery of angiotensin II type 1 receptor antisense inhibits angiotensin action in neurons from hypertensive rat brain.
Authors: Lu D , Raizada M K
Published: May 2006

Increased brain angiotensin II (AII) type 1 receptor (AT1R) expression has been implicated in the hyperactive brain angiotensin system and the development and maintenance of hypertension in the genetically spontaneously hypertensive (SH) rat. Neuronal cells in primary culture from the cardioregulatory-relevant brain areas (hypothalamus/brainstem) mimic increased brain AT1R gene expression and AT1R function of the adult SH rat. They have been utilized in the present study to determine whether cellular actions of AII could be regulated by the transfer of AT1R antisense (AT1R-AS) with the use of a retroviral-mediated gene delivery system developed for the central nervous system cultures. AII stimulates norepinephrine (NE) uptake in neuronal cultures of both normotensive (Wistar Kyoto) and SH rat brains. This neuromodulatory action is mediated by the AT1R subtype, is significantly higher in SH neurons, and is associated with a parallel stimulation of mRNAs for c-fos and NE transporter. Infection of neuronal cultures with a retrovirus vector that contains AT1R-AS (LNSV-AT1R-AS) results in an inhibition of AT1R-mediated stimulation of both c-fos and NE transporter mRNA, as well as NE uptake in both strains of rats; however, the inhibition is more pronounced in SH neurons compared with Wistar Kyoto rat brain neurons. The higher sensitivity of the SH rat brain neurons is further supported by our observation that a certain dose of LNSV-AT1R-AS that fails to induce inhibition of cellular actions of AII in WKY neurons causes a significant inhibition of AII actions in SH neurons. These observations show that retrovirally mediated delivery of AT1R-AS could be used to selectively control the actions of AII in primary neuronal cultures from SH rat brain.
Structure, expression, and chromosomal localization of the type I human vasoactive intestinal peptide receptor gene.
Authors: Sreedharan S P , Huang J X , Cheung M C , Goetzl E J
Published: May 2006

Vasoactive intestinal peptide (VIP) and other members of the pituitary adenylyl cyclase-activating peptide (PACAP) and secretin neuroendocrine peptide family are recognized with specificity by related G protein-coupled receptors. We report here the cloning, characterization, and chromosomal location of the gene encoding the human type I VIP receptor (HVR1), also termed the type II PACAP receptor. The gene spans approximately 22 kb and is composed of 13 exons ranging from 42 to 1400 bp and 12 introns ranging from 0.3 to 6.1 kb. Primer extension analysis with poly(A)+ RNA from human HT29 colonic adenocarcinoma cells indicated that the transcription initiation site is located at position -110 upstream of the first nucleotide (+1) of the translation start codon, and 75 nt downstream of a consensus CCAAT-box motif. The G+C-rich 5' flanking region contains potential binding sites for several nuclear factors, including Sp1, AP2, ATF, interferon regulatory factor 1, NF-IL6, acute-phase response factor, and NF-kappa B. The HVR1 gene is expressed selectively in human tissues with a relative prevalence of lung > prostate > peripheral blood leukocytes, liver, brain, small intestine > colon, heart, spleen > placenta, kidney, thymus, testis. Fluorescence in situ hybridization localized the HVR1 gene to the short arm of human chromosome 3 (3p22), in a region associated with small-cell lung cancer.
Convergent processing in honeybee vision: multiple channels for the recognition of shape.
Authors: Zhang S W , Srinivasan M V , Collett T
Published: May 2006

Advanced mammalian visual systems can recognize a familiar shape under a variety of viewing conditions. Recognition is possible whether the shape is presented in simple outline, as a random dot stereogram, or by motion contrast. We report here that bees have a similar ability: they can recognize a shape when it is learned through visual signals of one kind and subsequently viewed through another. The results reveal that (i) bees that have learned a shape defined in terms of luminance contrast can recognize the same shape when it is defined in terms of motion contrast, (ii) shapes that are delineated by motion contrast are discriminated through a channel that receives input only from the green photoreceptors, (iii) a shape learned through one class of signal is subsequently recognized via any of these other classes, and (iv) shape is memorized in a generic form regardless of whether it is initially sensed by green-contrast, blue-contrast, luminance-contrast, or motion-contrast signals.
Ptolemaiida, a new order of Mammalia--with description of the cranium of Ptolemaia grangeri.
Authors: Simons E L , Bown T M
Published: May 2006

All records of the exotic mammalian family Ptolemaiidae are known from 182 m of section in the lower to middle parts of the upper Eocene and lower Oligocene Jebel Qatrani Formation, Fayum Depression, Egypt. Previous tentative assignments of ptolemaiid affinity have suggested that these animals are allied with the primitive suborder Pantolesta (currently placed in the order Cimolesta). Though perhaps ultimately derived from an unknown member of that group, the likelihood that ptolemaiids constitute a distinct group is considered, and analysis of all known materials of Ptolemaia, Qarunavus, and Cleopatrodon demonstrates that these genera belong in their own order, the Ptolemaiida, described here. The morphologically unique dentition and only known ptolemaiid cranium, that of Ptolemaia grangeri, is described. Although Qarunavus and Cleopatrodon show some similarities in primitive characters to European merialine Paroxyclaenidae (suborder Pantolesta), their affinities clearly lie with Ptolemaia and the Ptolemaiida.
Interfacial activation-based molecular bioimprinting of lipolytic enzymes.
Authors: Mingarro I , Abad C , Braco L
Published: May 2006

Interfacial activation-based molecular (bio)-imprinting (IAMI) has been developed to rationally improve the performance of lipolytic enzymes in nonaqueous environments. The strategy combinedly exploits (i) the known dramatic enhancement of the protein conformational rigidity in a water-restricted milieu and (ii) the reported conformational changes associated with the activation of these enzymes at lipid-water interfaces, which basically involves an increased substrate accessibility to the active site and/or an induction of a more competent catalytic machinery. Six model enzymes have been assayed in several model reactions in nonaqueous media. The results, rationalized in light of the present biochemical and structural knowledge, show that the IAMI approach represents a straightforward, versatile method to generate manageable, activated (kinetically trapped) forms of lipolytic enzymes, providing under optimal conditions nonaqueous rate enhancements of up to two orders of magnitude. It is also shown that imprintability of lipolytic enzymes depends not only on the nature of the enzyme but also on the "quality" of the interface used as the template.
Human general transcription factor TFIIA: characterization of a cDNA encoding the small subunit and requirement for basal and activated transcription.
Authors: DeJong J , Bernstein R , Roeder R G
Published: May 2006

The human general transcription factor TFIIA is one of several factors involved in specific transcription by RNA polymerase II, possibly by regulating the activity of the TATA-binding subunit (TBP) of TFIID. TFIIA purified from HeLa extracts consists of 35-, 19-, and 12-kDa subunits. Here we describe the isolation of a cDNA clone (hTFIIA gamma) encoding the 12-kDa subunit. Using expression constructs derived from hTFIIA gamma and TFIIA alpha/beta (which encodes a 55-kDa precursor to the alpha and beta subunits of natural TFIIA), we have constructed a synthetic TFIIA with a polypeptide composition similar to that of natural TFIIA. The recombinant complex supports the formation of a DNA-TBP-TFIIA complex and mediates both basal and Gal4-VP16-activated transcription by RNA polymerase II in TFIIA-depleted nuclear extracts. In contrast, TFIIA has no effect on tRNA and 5S RNA transcription by RNA polymerase III in this system. We also present evidence that both the p55 and p12 recombinant subunits interact with TBP and that the basic region of TBP is critical for the TFIIA-dependent function of TBP in nuclear extracts.
The Ran/TC4 GTPase-binding domain: identification by expression cloning and characterization of a conserved sequence motif.
Authors: Beddow A L , Richards S A , Orem N R , Macara I G
Published: May 2006

Ran/TC4 is an essential, nuclear GTPase implicated in the initiation of DNA replication, entry into and exit from mitosis, and in nuclear RNA and protein transport through the nuclear pore complex. This diversity of functions suggests that Ran interacts with a large number of down-stream targets. Using an overlay assay, we detected a family of putative target proteins that associate with GTP-bound Ran. The sequence of only one such protein, HTF9a/RanBP1, is known. We have now cloned two additional Ran-binding proteins, allowing identification of a distinctive, highly conserved sequence motif of approximately 150 residues. This motif represents a minimal Ran-binding domain that stabilizes the GTP-bound state of Ran. The isolated domain also functions as a coactivator of Ran-GTPase-activating protein. Mutation of a conserved residue within the Ran-binding domain of HTF9a protein drastically reduced Ran binding. Ran-binding proteins coimmunoprecipitated with epitope-tagged Ran from cell lysates, suggesting that these proteins may associate in vivo. A previously uncharacterized Caenorhabditis elegans gene could encode a protein (96 kDa) possessing two Ran-binding domains. This open reading frame also contains similarities to nucleoporins, suggesting a functional link between Ran and nuclear pore complexes.
Retro and retroenantio analogs of cecropin-melittin hybrids.
Authors: Merrifield R B , Juvvadi P , Andreu D , Ubach J , Boman A , Boman H G
Published: May 2006

Hybrid analogs of cecropin A (CA) and melittin (M), which are potent antibacterial peptides, have been synthesized. To understand the structural requirements for this antibacterial activity, we have also synthesized the enantio, retro, and retroenantio isomers of two of the hybrids and their N-terminally acetylated derivatives. All analogs of CA(1-13)M(1-13)-NH2 were as active as the parent peptide against five test bacterial strains, but one bacterial strain was resistant to the retro and retroenantio derivatives. Similarly, all analogs of CA(1-7)M(2-9)-NH2 were active against four strains, while two strains were resistant to the retro and retroenantio analogs containing free NH3+ end groups, but acetylation restored activity against one of them. From these data it was concluded that chirality of the peptide was not a critical feature, and full activity could be achieved with peptides containing either all L- or all D-amino acids in their respective right-handed or left-handed helical conformations. For most of the bacterial strains, the sequence of these peptides or the direction of the peptide bonds could be critical but not both at the same time. For some strains, both needed to be conserved.
Regulation of blood pressure by the type 1A angiotensin II receptor gene.
Authors: Ito M , Oliverio M I , Mannon P J , Best C F , Maeda N , Smithies O , Coffman T M
Published: May 2006

The renin-angiotensin system plays a critical role in sodium and fluid homeostasis. Genetic or acquired alterations in the expression of components of this system are strongly implicated in the pathogenesis of hypertension. To specifically examine the physiological and genetic functions of the type 1A receptor for angiotensin II, we have disrupted the mouse gene encoding this receptor in embryonic stem cells by gene targeting. Agtr1A(-/-) mice were born in expected numbers, and the histomorphology of their kidneys, heart, and vasculature was normal. AT1 receptor-specific angiotensin II binding was not detected in the kidneys of homozygous Agtr1A(-/-) mutant animals, and Agtr1A(+/-) heterozygotes exhibited a reduction in renal AT1 receptor-specific binding to approximately 50% of wild-type [Agtr1A(+/+)] levels. Pressor responses to infused angiotensin II were virtually absent in Agtr1A(-/-) mice and were qualitatively altered in Agtr1A(+/-) heterozygotes. Compared with wild-type controls, systolic blood pressure measured by tail cuff sphygmomanometer was reduced by 12 mmHg (1 mmHg = 133 Pa) in Agtr1A(+/-) mice and by 24 mmHg in Agtr1A(-/-) mice. Similar differences in blood pressure between the groups were seen when intraarterial pressures were measured by carotid cannulation. These studies demonstrate that type 1A angiotensin II receptor function is required for vascular and hemodynamic responses to angiotensin II and that altered expression of the Agtr1A gene has marked effects on blood pressures.
The ATX1 gene of Saccharomyces cerevisiae encodes a small metal homeostasis factor that protects cells against reactive oxygen toxicity.
Authors: Lin S J , Culotta V C
Published: May 2006

In aerobic organisms, protection against oxidative damage involves the combined action of highly specialized antioxidant enzymes, such as superoxide dismutase (SOD) and catalase. Here we describe the isolation and characterization of another gene in the yeast Saccharomyces cerevisiae that plays a critical role in detoxification of reactive oxygen species. This gene, named ATX1, was originally isolated by its ability to suppress oxygen toxicity in yeast lacking SOD. ATX1 encodes a 8.2-kDa polypeptide exhibiting significant similarity and identity to various bacterial metal transporters. Potential ATX1 homologues were also identified in multicellular eukaryotes, including the plants Arabidopsis thaliana and Oryza sativa and the nematode Caenorhabditis elegans. In yeast cells, ATX1 evidently acts in the transport and/or partitioning of copper, and this role in copper homeostasis appears to be directly relevant to the ATX1 suppression of oxygen toxicity: ATX1 was incapable of compensating for SOD when cells were depleted of exogenous copper. Strains containing a deletion in the chromosomal ATX1 locus were generated. Loss of ATX1 function rendered both mutant and wild-type SOD strains hypersensitive toward paraquat (a generator of superoxide anion) and was also associated with an increased sensitivity toward hydrogen peroxide. Hence, ATX1 protects cells against the toxicity of both superoxide anion and hydrogen peroxide.
Stable loop in the crystal structure of the intercalated four-stranded cytosine-rich metazoan telomere.
Authors: Kang C , Berger I , Lockshin C , Ratliff R , Moyzis R , Rich A
Published: May 2006

In most metazoans, the telomeric cytosine-rich strand repeating sequence is d(TAACCC). The crystal structure of this sequence was solved to 1.9-A resolution. Four strands associate via the cytosine-containing parts to form a four-stranded intercalated structure held together by C.C+ hydrogen bonds. The base-paired strands are parallel to each other, and the two duplexes are intercalated into each other in opposite orientations. One TAA end forms a highly stabilized loop with the 5' thymine Hoogsteen-base-paired to the third adenine. The 5' end of this loop is in close proximity to the 3' end of one of the other intercalated cytosine strands. Instead of being entirely in a DNA duplex, this structure suggests the possibility of an alternative conformation for the cytosine-rich telomere strands.
In vitro cleavage and joining at the viral origin of replication by the replication initiator protein of tomato yellow leaf curl virus.
Authors: Laufs J , Traut W , Heyraud F , Matzeit V , Rogers S G , Schell J , Gronenborn B
Published: May 2006

Replication of the single-stranded DNA genome of geminiviruses occurs via a double-stranded intermediate that is subsequently used as a template for rolling-circle replication of the viral strand. Only one of the proteins encoded by the virus, here referred to as replication initiator protein (Rep protein), is indispensable for replication. We show that the Rep protein of tomato yellow leaf curl virus initiates viral-strand DNA synthesis by introducing a nick in the plus strand within the nonanucleotide 1TAATATT decreases 8AC, identical among all geminiviruses. After cleavage, the Rep protein remains bound to the 5' end of the cleaved strand. In addition, we show that the Rep protein has a joining activity, suggesting that it acts as a terminase, thus resolving the nascent viral single strand into genome-sized units.
Fostering Multidisciplinary Engagement: Communication Challenges for Social Research on Emerging Digital Technologies
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Authors: Dutton William H. , Carusi Annamaria , Peltu Malcolm
Published: May 2006

There is wide agreement on the value of multidisciplinary social research related to information and communication technologies. This paper provides insights into the dynamics at play in these studies, drawing on an in‐depth analysis of exchanges among an international group of experts from many relevant disciplines who participated in a workshop on research into the social implications of emerging digital technologies. In addition to identifying some distinctive new challenges facing this field, the paper suggests how understanding ways to foster productive engagement in discussing and developing issues and joint work could lead to more useful multidisciplinary partnerships.
Reclassification of Arthrobacter duodecadis Lochhead 1958 as Tetrasphaera duodecadis comb. nov. and emended description of the genus Tetrasphaera
Authors: Ishikawa Takashi , Yokota Akira
Published: May 2006

Phylogenetic analysis based on 16S rRNA gene sequences and chemotaxonomic features ofArthrobacter duodecadisLochhead 1958 indicated that the bacterium belonged within the genusTetrasphaera.A. duodecadisIAM 14868Tcould be distinguished from other species by the presence of 3-hydroxymeso-diaminopimelic acid in the peptidoglycan and a series of 10-methyl fatty acids. In addition, DNA–DNA relatedness studies indicated that the strain belonged to a genomic species that could be readily distinguished from its nearest neighbours, the type strains ofTetrasphaera elongata,Tetrasphaera japonicaandTetrasphaera australiensis. These features support our proposal to reclassifyA. duodecadisin the genusTetrasphaera, asTetrasphaera duodecadiscomb. nov. The type strain is IAM 14868T(=NBRC 12959T=ATCC 13347T=NCIMB 9222T). An emended description of the genusTetrasphaerais given.
Nesterenkonia aethiopica sp. nov., an alkaliphilic, moderate halophile isolated from an Ethiopian soda lake
Authors: Delgado Osvaldo , Quillaguamán Jorge , Bakhtiar Shahrzad , Mattiasson Bo , Gessesse Amare , Hatti-Kaul Rajni
Published: May 2006

Strain DSM 17733T, isolated from the shore of Lake Abjata in Ethiopia, is a heterotrophic, alkaliphilic, moderately halophilic, Gram-positive, strictly aerobic, non-motile,non-endospore-forming bacterium. The organism grows optimally at 30–37 °C, pH 9 and 3 % (w/v) NaCl. Analysis of the cell wall showed the presence of murein of the typel-lys–gly–l-Glu, variation A4α. The G+C content of the genomic DNA was 69.0 mol%. Sequence analysis of 16S rRNA gene sequence of strain DSM 17733Tplaced the isolate in the genusNesterenkonia. DNA–DNA hybridization of DSM 17733Twith those organisms with the closest phylogenetic affiliation, i.e.Nesterenkonia halobia,Nesterenkonia lacusekhoensisandNesterenkonia xinjiangensis, gave relatedness values of 48.5 %, 63.7 % (repetition, 57.2 %) and 35.7 % (repetition, 29.3 %), respectively. On the basis of both phenotypic and phylogenetic criteria and the low levels of DNA–DNA relatedness with the phylogenetically closest speciesN. xinjiangensisandN. halobia, it is proposed that the isolate be classified in a novel species,Nesterenkonia aethiopicasp. nov. The type strain is DSM 17733T(=CCUG 48939T).
Phylogenetic relationships within the order Halobacteriales inferred from 16S rRNA gene sequences
Authors: Wright André-Denis Girard
Published: May 2006

Phylogenetic relationships within the halophilic archaea were inferred from comparisons of the 16S rRNA gene sequences from 61 strains, representing 18 genera with validly published names within the orderHalobacteriales. Trees produced using distance-matrix (least-squares and neighbour-joining) methods affirm with strong bootstrap support that the members of the orderHalobacterialesare a monophyletic group. Ten genera were supported as monophyletic groups [Haloarcula,Halobiforma,Halococcus,Haloferax,Halorubrum,Halosimplex(multiple sequences from a single strain),Natrialba,Natrinema,NatronococcusandNatronorubrum] and eight genera were represented by a single strain (Halobacterium,Halobaculum,Halogeometricum,Halomicrobium,Halorhabdus,Halosimplex,NatronobacteriumandNatronomonas). The genusHaloterrigenawas always paraphyletic, and the phylogenetic placement of and sister groups toHalobacteriumandNatronomonascould not be resolved. Both treeing methods failed to resolve the deep branching patterns within the orderHalobacterialesand the relationships between the major clades. Additional representation from the currently monospecific genera and/or the use of other macromolecules may be required to resolve the relationships within the orderHalobacteriales.
Leuconostoc pseudoficulneum sp. nov., isolated from a ripe fig
Authors: Chambel Lélia , Chelo Ivo M. , Zé-Zé Líbia , Pedro Luis G. , Santos Mário A. , Tenreiro Rogério
Published: May 2006

Six strains of lactic acid bacteria (LAB) were isolated from a ripe fig. These strains constituted a highly homogeneous, but distinct, cluster that was separate from other LAB species in a polyphasic approach including dot-blot DNA–DNA hybridization, SDS-PAGE whole-cell protein profiling, carbohydrate fermentation ability, growth characteristics, enzymic profiling, pulsed-field gel electrophoresis macrorestriction analysis and RFLPs. Phylogenetic analysis based on 16S rRNA gene sequencing positioned a representative strain, LC51T, in a distinct line of descent within the recently described clade comprisingLeuconostoc ficulneum,Leuconostoc fructosumandLeuconostoc durionis;L. ficulneumwas its closest neighbour (98 % sequence similarity). DNA–DNA hybridization values and chemotaxonomic and biochemical characteristics, including enzymic profiles detected with API ZYM microtubes, confirmed that this group of strains is distinct fromL. ficulneumand represents a novel species within the genusLeuconostoc. Taking into account the common origin and phylogenetic proximity, the nameLeuconostoc pseudoficulneumsp. nov. is proposed. Strain LC51T(=DSM 15468T=CECT 5759T) is the type strain; the DNA G+C content of this strain is 44.5 mol%.
Streptacidiphilus oryzae sp. nov., an actinomycete isolated from rice-field soil in Thailand
Authors: Wang Liming , Huang Ying , Liu Zhiheng , Goodfellow Michael , Rodríguez Carlos
Published: May 2006

The taxonomic position of ten acidophilic actinomycetes isolated from an acidic rice-field soil was established using a polyphasic approach. 16S rRNA gene sequences determined for the isolates were aligned with corresponding sequences of representatives of the generaKitasatospora,StreptacidiphilusandStreptomycesand phylogenetic trees were inferred using four tree-making algorithms. The isolates had identical sequences and formed a distinct branch at the periphery of theStreptacidiphilus16S rRNA gene tree. The chemotaxonomic and morphological properties of representative isolates were consistent with their assignment to the genusStreptacidiphilus. The isolates shared nearly identical phenotypic profiles that readily distinguished them from representatives of the established species ofStreptacidiphilus. It is evident from the genotypic and phenotypic data that the isolates form a homogeneous group that corresponds to a novel species in the genusStreptacidiphilus. The name proposed for this new taxon isStreptacidiphilus oryzaesp. nov.; the type strain is strain TH49T(=CGMCC 4.2012T=JCM 13271T).
The histidine utilization (hut) genes of Pseudomonas fluorescens SBW25 are active on plant surfaces, but are not required for competitive colonization of sugar beet seedlings
Authors: Zhang Xue-Xian , George Andrew , Bailey Mark J. , Rainey Paul B.
Published: May 2006

The ability to monitor the spatial and temporal distribution of signals in complex environments is necessary for an understanding of the function of bacteria in the wild. To this end, an existing recombinase-based transcriptional reporter strategy (recombinase-basedin vivoexpression technology, RIVET) has been extended and applied to the plant-colonizing bacteriumPseudomonas fluorescensSBW25. Central to the project was a rhizosphere-inducible locus,rhi14, which functional analyses show ishutT, a histidine-inducible gene that is required for histidine utilization. A transcriptional fusion betweenhutTand a promoterless site-specific recombinase (tnpRmut168) results in excision of a chromosomally integrated tetracycline-resistance cassette in a histidine-dependent manner. The dose- and time-responsiveness of the promoterless recombinase to histidine closely mirrored the histidine responsiveness of an identicalhutTfusion to promoterlesslacZ. To demonstrate the effectiveness of the strategy, the activity ofhutTwas monitored on sugar beet seedlings. Low levels of transcriptional activity were detected in the phyllosphere, rhizosphere and in plant extract, but not in vermiculite devoid of seedlings. The histidine concentration in the rhizosphere was estimated to be 0.6 μg ml−1. The ecological significance of thehutlocus was examined by competing ahutTdeletion mutant against the wild-type during colonization of sugar beet seedlings. No impact on competitive fitness was detected, suggesting that the ability to utilize plant-derived histidine is not essential for bacterial colonization.
WEGENER’S GRANULOMATOSIS COMPLICATED WITH APHTHOID COLITIS
Authors: Umehara Yasushi , Kudo Masatoshi , Minami Yasunori , Tei Hiroshi , Ueshima Kazuomi , Fukunaga Toyokazu , Nakatani Tatsuya , Matsui Shigenaga , Kitano Masayuki , Shiomi Mikio
Published: May 2006

A 58‐year‐old man was admitted with upper abdominal pain and high fever. There was no abnormality on chest X‐ray, abdominal ultrasonography, abdominal CT and upper gastrointestinal endoscopy. Antineutrophil cytoplasmic antibodies (C‐ANCA) titers were high and a chest CT scan depicted multiple nodules in the bilateral lungs. A diagnosis of Wegener’s granulomatosis was therefore made. Three weeks after admission, diarrhea and bloody stool developed. Colonoscopy revealed many aphthoid lesions surrounded by redness in the entire colon. Although the biopsy from aphtha did not show vasculitis or granuloma, the aphthoid lesions were suspected as a complication of Wegener’s granulomatosis. As a result of predonisolone medication (60 mg/day), the plasma C‐reactive protein (CRP) and high fever improved promptly. In conclusion, although colonic involvement in a patient with Wegener’s granulomatosis is extremely rare, it is important to keep in mind that colonic lesions might be due to vasculitis in ANCA‐positive disease, such as Wegener’s granulomatosis.
The behavioural and physiological response of Atlantic cod Gadus morhua L. to short‐term acute hypoxia
Authors: Johansen J. L. , Herbert N. A. , Steffensen J. F.
Published: May 2006

The average rate of swimming speed and the physiological status or stress of individual Atlantic cod Gadus morhua was monitored in response to short‐term acute (STA) hypoxia (i.e. partial pressure of oxygen, , reduced from 20·9 to 4·3 kPa within 1 h at 10° C). The STA hypoxic response of Atlantic cod was associated with a large primary increase (+29%) and a large secondary decrease (−54%) in swimming speed as well as major physiological stress (e.g. plasma cortisol = 214·7 ng ml−1 and blood lactate = 2·41 mmol l−1).
Coordinate responses of transcription factors to ecdysone during programmed cell death in the anterior silk gland of the silkworm, Bombyx mori
Authors: Sekimoto T. , Iwami M. , Sakurai S.
Published: May 2006

Programmed cell death (PCD) in Bombyx mori anterior silk glands (ASGs) is triggered by 20‐hydroxyecdysone (20E). We examined the expression profiles and effects of 20E on 11 transcription factor genes in the fifth instar to determine whether they demonstrate the hierarchical control seen in Drosophila PCD. Results indicate that EcR‐A and usp‐2, but not EcR‐B1 or usp‐1, may be components of the ecdysone receptor complex. Up‐regulation of E75A, BHR3, and three BR‐C isoforms, but not E75B, appeared to be associated with the induction of PCD. βFTZ‐F1 was not expressed during PCD execution. Thus, gene control in B. mori ASGs differs from that in Drosophila salivary glands, despite both tissues undergoing PCD in response to 20E at pupal metamorphosis.
The Arabidopsis ARGOS‐LIKE gene regulates cell expansion during organ growth
Authors: Hu Yuxin , Poh Huay Mei , Chua Nam‐Hai
Published: May 2006

Cell expansion, and its coordination with cell division, plays a critical role in the growth and development of plant organs. However, the genes controlling cell expansion during organogenesis are largely unknown. Here, we demonstrate that a novel Arabidopsis gene, ARGOS‐LIKE (ARL), which has some sequence homology to the ARGOS gene, is involved in this process. Reduced expression or overexpression of ARL in Arabidopsis results in smaller or larger cotyledons and leaves as well as other lateral organs, respectively. Anatomical examination of cotyledons and leaves in ARL transgenic plants demonstrates that the alteration in size can be attributed to changes in cell size rather than cell number, indicating that ARL plays a role in cell expansion‐dependent organ growth. ARL is upregulated by brassinosteroid (BR) and this induction is impaired in the BR‐insensitive mutant bri1, but not in the BR‐deficient mutant det2. Ectopic expression of ARL in bri1–119 partially restores cell growth in cotyledons and leaves. Our results suggest that ARL acts downstream of BRI1 and partially mediates BR‐related cell expansion signals during organ growth.
MHC class I variation associates with parasite resistance and longevity in tropical pythons
Authors: Madsen T. , Ujvari B.
Published: May 2006

Using restriction fragment length polymorphism (RFLP) we identified 26 unique major histocompatibility complex (MHC) genotypes in 104 water pythons. We observed a significant independent association between reduced blood parasite load (Hepatozoon sp.) and python body length/age, presence of a specific RFLP fragment (C-fragment) and the overall number of fragments. The parasite has a negative impact on several python life-history traits such as growth, nutritional status and longevity. Thus, the C-fragment could be considered a ‘good gene’ (a fitness-enhancing genetic element). However, while the number of fragments affected parasite load, the association between level of parasitaemia and fragment number was not linear, and, hence, minimum parasite infection level was achieved at an intermediate number of fragments. Intermediate MHC fragment numbers were also observed among the largest/oldest pythons, suggesting that both a specific fragment and intermediate levels of MHC polymorphism enhanced python longevity. Thus, our results suggest python MHC is subject to both frequency-dependent and balancing selection.
Complementary and alternative medicine use in asthma: Who is using what?
Authors: SLADER Cassandra A. , REDDEL Helen K. , JENKINS Christine R. , ARMOUR Carol L. , BOSNIC‐ANTICEVICH Sinthia Z.
Published: May 2006

Abstract:  Consumer interest in complementary and alternative medicine (CAM) has grown dramatically in Western countries in the past decade. However, very few patients volunteer information about CAM use unless directly questioned by their health‐care practitioner. Therefore, by being informed about the prevalence and modality of CAM use for asthma, as well as characteristics of users, health‐care practitioners may be better able to identify patients who use CAM. In turn, this may facilitate proactive discussion and optimization of the patient’s overall asthma management. This review aims to summarize the current knowledge about use of CAM by people with asthma, and to assess the applicability of the available studies to the broader asthmatic population. Computerized literature searches were conducted on Medline, Embase, Cochrane and Allied and Complementary Medicine (AMED) databases from their inception to 13 April 2005. Search terms included: complementary medicine/therapies, alternative medicine/therapies and asthma. The bibliographies of accessible articles were searched for further papers. Seventeen studies have examined the use of CAM by people with asthma. The reported level of use for adults ranged from 4% to 79%, and for children from 33% to 89%. Among the most commonly used CAMs were: breathing techniques, herbal products, homeopathy and acupuncture. There is no strong evidence for effectiveness for any of these modalities. There is little consistency among available prevalence studies making conclusions difficult. Nevertheless, the high rates of CAM use reported in some studies indicate that CAM use should be taken into account when managing patients with asthma.
Clinical implication of atypical cells from sputum in patients without lung cancer
Authors: KO Dong Seok , MOON Kyung Chul , CHUNG Doo Hyun , HWANG Yong Il , YOO Chul‐Gyu , KIM Young Whan , HAN Sung Koo , SHIM Young‐Soo , YIM Jae‐Joon
Published: May 2006

Objective and background:  Atypical—but not definitely malignant—cells in cytological examinations of sputum are usually associated with lung cancers. However, atypical cells are occasionally identified in patients without lung cancer. The aim of this study was to determine the clinical implication of the atypical cells from sputum in patients without lung cancer or other malignancies.

Methodology:  All patients with atypical cells observed following cytological examination of sputum on one or more occasion over a 2‐year period in Seoul National University Hospital were enrolled. After exclusion of patients followed up for less than 6 months, their clinical data were reviewed retrospectively.

Results:  Among 601 enrolled patients with atypical cells, lung cancers were diagnosed within 30 days of identification of atypical cells in 542 (90.2%) patients. Five out of 59 patients who had no evidence of lung cancer, were subsequently diagnosed with lung cancer or other malignancies following a mean observation of 164 days. In the other 54 patients without subsequent malignancies, the most common respiratory diseases were pneumonia including tuberculosis.

Conclusions:  The subsequent development of malignancy in patients with atypical cells in sputum despite a thorough evaluation was rare, and close observation without invasive diagnostic procedures might be simply required in these patients.
Population‐based prospective molecular and conventional epidemiological study of tuberculosis in Hong Kong
Authors: CHAN‐YEUNG Moira , KAM Kai‐man , LEUNG Chi‐chiu , WANG Julie , YEW Wing‐wai , LAM Chak‐wah , TAM Cheuk‐ming
Published: May 2006

Objective:  To study the transmission of tuberculosis using conventional and molecular epidemiology in Hong Kong.

Methods:  All patients with positive sputum culture for Mycobacterium tuberculosis residing on the Island of Hong Kong were recruited from May 1999 to April 2002. The restriction fragment length polymorphism technique was used to determine DNA patterns of isolates of M. tuberculosis using the IS6110 probe, supplemented by pTBN12 as a secondary probe.

Results:  One thousand five hundred and fifty‐three of 2337 (66%) of the patients with bacteriologically confirmed tuberculosis had restriction fragment length polymorphism analysis of their M. tuberculosis isolates. Four hundred and fifty‐four (29.2%) patients belonging to 143 clusters were identified; the estimated rate of recent transmission was 20–24%. Significant predictors of clustering included young‐age groups (<40 years) versus those >60 years of age (adjusted odds ratio (OR) 1.96, 95% confidence interval 1.47–2.62), permanent residency versus new or non‐residents (adjusted OR 3.40, 95% 1.84–6.26) and previous default from treatment versus new cases (adjusted OR 6.12, 95% confidence interval 1.82–20.5). Alcohol and drug abuse, history of imprisonment and HIV infection were not significant risk factors for molecular clustering. Of patients belonging to clusters, 5.1% had definite, 5.5% had probable and 24.4% had possible epidemiological link, suggesting casual contact may be responsible for a high proportion of the clustered cases.

Conclusion:  One‐fifth to one quarter of the new cases of active tuberculosis in Hong Kong are due to recent transmission. In addition to early diagnosis and successful treatment of all active disease, treatment of latent disease should receive more attention in the control of tuberculosis in Hong Kong.
Comparative analysis of the effects of hubble‐bubble (Sheesha) and cigarette smoking on respiratory and metabolic parameters in hubble‐bubble and cigarette smokers
Authors: AL MUTAIRI Sana S. , SHIHAB‐ELDEEN Aida A. , MOJIMINIYI Olusegun A. , ANWAR Alia Aisha
Published: May 2006

Objectives and background:  Hazard of smoking tobacco is believed to be minimized by smoking hubble‐bubble (HB) instead of cigarettes. Our aims were to (i) develop an assay for estimating nicotine and cotinine; and (ii) evaluate the effect of smoking on respiratory and metabolic parameters in cigarette and HB smokers.

Methods:  Urine samples were collected from 152 volunteer smokers (75 cigarette and 77 HB) as well as from 16 healthy controls. We optimized an HPLC method for the determination of nicotine and cotinine. Subjects were asked to complete a chronic respiratory symptoms questionnaire and to undergo spirometry. Fasting blood samples were collected for the determination of their lipid profile.

Results:  The intra‐assay coefficients of variation for nicotine and cotinine were 16.6% and 6.6%, respectively. The mean of cotinine in cigarette smokers (1321.4 ng/mL) was significantly (P = 0.008) higher than the mean cotinine (677.6 ng/mL) in HB smokers. The mean nicotine level in cigarette smokers (1487.3 ng/mL) was significantly (P < 0.0001) higher than the mean nicotine (440.5 ng/mL) in HB smoker. The urinary cotinine and nicotine levels of the control subjects were lower than the detection levels of the assay. The mean high‐density lipoprotein cholesterol was lower in cigarette smokers (0.99 mmol/L) compared with HB smoker smokers (1.02 mmol/L) but this was not significant (P = 0.28). Spirometric values were comparable among the three groups but the chronic respiratory symptoms in the smoking groups appeared at an earlier age in the HB smokers compared with the cigarettes smokers (P < 0.05).

Conclusion:  Smoking HB does not reduce the risk of tobacco exposure and it’s potentially harmful metabolites on health.