bluuebunny/crossref_metadata_2025 huggingface dataset:
PCR‐Mediated Recombination between Cryptosporidium spp. of Lizards and Snakes
Authors: ZHOU LING , YANG CHUNFU , XIAO LIHUA
Published: July 2005

ABSTRACT: The presence or absence of genetic recombination has often been used as one of the criteria for Cryptosporidium species designation and population structure delineation. During a recent study of cryptosporidiosis in reptiles that were housed in the same room, 4 lizards were found to have concurrent infections of C. serpentis (a gastric parasite) and C. saurophilum (an intestinal parasite), and 6 snakes were concurrently infected with C. serpentis, C. sattrophitmm and a new Cryptosporidium as indicated by PCR‐RFLP analysis of the SSU rRNA gene. DNA sequence analysis of cloned PCR products confirmed the diagnosis of mixed infections. Surprisingly, it appeared that 11 of the 22 clones (8 and 14 clones from a lizard and a snake, respectively) had chimeric sequences of two Cryptosporidium spp. BootScan analysis indicated the existence of recombinants among the cloned sequences and detection of the informative sites confirmed the BootScan results. Because the probability for genetic recombination between gastric and intestinal parasites is small, these hybrid sequences were likely results of PCR artifacts due to the presence of multiple templates. This was confirmed by PCR‐sequencing analysis of single‐copy templates using diluted DNA samples. Direct sequencing of 69 PCR products from 100‐to 1.000‐fold diluted DNAs from the same snake and lizard produced only sequences of C. serpentis, C. saurophilum and the unnamed Cryntosnoridium., sp. Thus, care should be taken to eliminate PCR artifacts when determining the presence of genetic recombination or interpreting results of population genetic studies.
A Molecular Biologic Study of Enterocytozoon bieneusi in HIV‐Infected Patients in Lima, Peru
Authors: SULAIMAN IRSHAD M. , BERN CARYN , GILMAN ROBERT , CAMA VITALIANO , KAWAI VIVIAN , VARGAS DANIEL , TICONA EDUARDO , VIVAR ALDO , LXIAO LIHUA
Published: July 2005

ABSTRACT. A cross‐sectional study was conducted to examine the genotype distribution of Enterocytozoon bieneusi in HIV‐infected patients who visited two government hospitals in Lima, Peru from January 2000 through March 2003. Microsporidia were detected by microscopy in 105 (3.9%) of 2,672 patients. A total of 212 stool samples from 89 microsporidia‐positive patients were genotyped by sequence analysis of the internal transcribed spacer (ITS) region of the rRNA gene. A 392‐bp fragment containing the complete ITS region was amplified and sequenced. Multiple alignments and phylogenetic analysis of these ITS sequences identified 11 distinct genotypes of E. bieneusi (Peru‐1 to Peru‐11), 6 of which were new genotypes not reported before. The remaining 5 genotypes had nucleotide sequences identical to those previously reported in humans, cats, pigs, and wild mammals. All the 11 E. bieneusi‐genotypes identified are genetically related, and members of the group have been previously found in humans, domestic animals, and some wild mammals. Thus, there is a high genetic diversity of E. bieneusi in humans in Peru, and zoonotie transmission is possible if humans are in close contact with infected animals.
Influence of Climatic Factors on Pneumocys Carriage within a Socially Organized Group of Immunocompetent Macaques (Macaca fascicularis)
Authors: DEMANCHE CHRISTINE , WANERT FANELIE , HERRENSCHMIDT NICOLAS , MOUSSU CLAIRE , DURAND‐JOLY ISABELLE , DEI‐CAS EDUARDO , CHERMETTE RENE , GUILLOT JACQUES
Published: July 2005

ABSTRACT. As monkeys‐derived Pneumocystis is closely related to P. jirovecii, simian populations should be considered as valuable models for the understanding of the epidemiology of human pneumocystosis. In the present study, the impact of environmental factors on the carriage of Pneumocystis was evaluated in socially organized group of immunocoinpetent macaques (Macuca fascicularis). The tribe, maintained in partial release al the Primatology Center of Strasbourg in France, comprised 29 animals at the end of the study. From December 2000 to November 2002, deep nasal swab samples were collected monthly from each animal under general anaesthesia. The presence of Pneurmocystis DNA was assessed by nested PCR of mtLSU rRNA gene. No case of pneumocystosis was reported during the study. Pneumocystis DNA was detected in 166 out 01 481 swab samples examined (34.5%). The number of macaques with detectable Pneumocystis DNA was highly variable from one month to another. However, Pneumocystis carriage was clearly correlated to the mean precipitation rates.
Ancient Weapons for Attack and Defense: the Pore‐forming Polypeptides of Pathogenic Enteric and Free‐living Amoeboid Protozoa1
Authors: LEIPPE MATTHIAS , HERBST ROSA
Published: July 2005

Pore‐forming polypeptides have been purified from several amoeboid protozoans that are well‐known human pathogens. Obligate enteric parasites, such as Entamoeba histolytica, and free‐living but potentially highly pathogenic species, such as Naegleria fowleri, contain these cytolytic molecules inside cytoplasmic granules. Comprehensive functional and structural studies have been conducted that include isolation of the proteins from their natural sources, monitoring of their biological activity towards different targets, and molecular cloning of the genes of their precursors. In the case of the most prominent member of the protein family, with respect to protozoans, the three‐dimensional structure of amoebapore A was solved recently. The amoebic pore‐forming polypeptides can rapidly perforate human cells. The antibacterial activity of amoebapores and of related polypetides from free‐living protozoa points to a more vital function of these molecules: inside the digestive vacuoles they combat growth of phagocytosed bacteria which are killed when their cytoplasmic membranes are permeabilized. The concommitant activity of these proteins towards host cells may be due to a coincidental selection for an efficient effector molecule. Nonetheless, several lines of evidence indicate that these factors are involved in pathogenesis of fatal diseases induced by amoeboid protozoa.
Molecular Phylogenetic Analysis Places Percolomonas cosmopolites within Heterolobosea: Evolutionary Implications
Authors: NIKOLAEV SERGEY I. , MYLNIKOV ALEXANDRE P. , BERNEY CEDRIC , FAHRNI JOSE , PAWLOWSKI JAN , ALESHIN VLADIMIR V. , PETROV NIKOLAY B.
Published: July 2005

Percolomonas cosmopolitus is a common free‐living flagellate of uncertain phylogenetic position that was placed within the Heterolobosea on the basis of ultrastructure studies. To test the relationship between Percolomonas and Heterolobosea, we analysed the primary structure of the actin and small‐subunit ribosomal RNA (SSU rRNA) genes of P. cosmopolitus as well as the predicted secondary structure of the SSU rRNA. Percolomonas shares common secondary structure patterns of the SSU rRNA with heterolobosean taxa, which, together with the results of actin gene analysis, confirms that it is closely related to Heterolobosea. Phylogenetic reconstructions based on the sequences of the SSU rRNA gene suggest Percolomonas belongs to the family Vahlkampliidae. The first Bayesian analysis of a large taxon sampling of heterolobosean SSU rRNA genes clarifies the phylogenetic relationships within this group.
Co‐infection of the Macronucleus ofParamecium caudatumby Free‐Living Bacteria Together with the InfectiousHolospora obtusa
Authors: FOKIN SERGEI O. , SKOVORODKIN ILYA N. , SCHWEIKERT MICHAEL , GÖRTZ HANS‐D.
Published: July 2005

Infection experiments were performed incubatingParamecium caudatumwith non‐infectious free‐living bacteria or weakly infectious intracellular bacteria together with the infectiousHolospora obtusa. Two of four non‐infectious free‐living bacteria (Enterobacter aerogenesandKlebsiella pneumoniae) were found to get into the nuclei when added toParameciumtogether withH. obtusa. The endonuclear bacteriumNonospora macronucleatathat is weakly infectious by itself increases its infectivity when presented together with the infectious holosporas. The results provide evidence thatH. obtusamay facilitate entry of other, non‐infectious bacteria into the nuclei ofParamecium.
Inhibition of Vorticetta microstoma Stalk Formation by Wheat Germ Agglutinin
Authors: BRAMUCCI MICHAEL G. , NAGARAJAN VASANTHA
Published: July 2005

Fluorescently labeled conjugates of wheat germ agglutinin and concanavalin A stained the contractile stalk but not the cell body of Vorticetta microstoma trophonts. Binding of the fluorescent conjugants did not noticeably alter the activity of the trophonts. However, unconjugated wheat germ agglutinin prevented free swimming telotrochs from adhering to a glass surface and deploying a contractile stalk during differentiation into trophonts. These observations indicated that the stalk, the material that binds the stalk to surfaces, and the precursors for these components have saccharide residues in common.
A Molecular Biological Approach to the Phylogenetic Position of the Genus Hyperamoeba
Authors: WALOCHNIK JULIA , MICHEL ROLF , ASPÖCK HORST
Published: July 2005

In 1923 Alexeieff described a new amoebic species within a new genus and named it Hyperamoeba flagellata. This amoeba exhibits three life cycle stages, an amoeboid trophozoite, a flagellated stage, and a cyst‐like the heteroloboseans, the mastigamoebae, and several slime moulds. Since then more strains have been isolated and relationships to the protostelids and cercomonads and to the myxogastrid plasmodial slime moulds have been suggested. However, up to now the classification and phylogenetic position of the hyperamoebae has remained unclear. The aim of our study was to make an approach to the phylogeny of the genus Hyperamoeba with combined morphological and molecular biological data. Since 1988 we have isolated and collected Hyperamoeba‐like, strains from different aquatic and terrestrial sources. The 18S rDNA‐sequences of 8 new Hyperamoeba strains isolated from various habitats were analysed and a cluster analysis was performed including all other available hyperamoebae. Altogether, the results of our study corroborate the relatedness of Hyperamoeba to various slime moulds. However, the hyperamoebae do not seem to be a monophyletic group, clearly putting the validity of the genus Hyperamoeba into question.
Pyruvate Formate Lyase (PFL) and PFL Activating Enzyme in the Chytrid FungusNeocallimastix frontalis: A Free‐Radical Enzyme System Conserved Across Divergent Eukaryotic Lineages1
Authors: GELIUS‐DIETRICH GABRIEL , HENZE KATRIN
Published: July 2005

Fermentative formate production involves the activity of pyruvate formate lyase, an oxygen‐sensitive enzyme that employs a glycyl radical in its reaction mechanism. While common among anaerobic prokaryotes, this enzyme has so far been found in only two distantly related eukaryotic lineages, anaerobic chytridiomycetes and chlorophytes. Sequence comparisons of homologues from the chytridiomycetesPiromycesandNeocallimastix, the chlorophyteChlamydomonas, and numerous prokaryotes suggest a single, eubacterial origin of eukaryotic pyruvate formate lyases. Pyruvate formate lyase activating enzyme introduces the glycyl radical into the pyruvate formate lyase protein chain. We discovered this enzyme, which had not previously been reported from eukaryotes, in the same two eukaryotic lineages and show that it shares a similar evolutionary history to pyruvate formate lyase. Sequences with high homology to pyruvate formate lyase activating enzyme were identified in the genomes of the anaerobic protozoan parasitesTrichomonas vaginalis, Entamoeba histolytica, andGiardia intestinalis. While the occurrence of pyruvate formate lyase activating enzyme together with pyruvate formate lyase in fungi and chlorophytes was to be expected, the target protein of a glycyl radical enzyme‐activating enzyme in these protozoa remains to be identified.
Parasites and Phytoplankton, with Special Emphasis on Dinoflagellate Infections1
Authors: PARK MYUNG GIL , YIH WONHO , COATS D. WAYNE
Published: July 2005

ABSTRACT. Planktonic members of most algal groups are known to harbor intracellular symbionts, including viruses, bacteria, fungi, and protozoa. Among the dinoflagellates, viral and bacterial associations were recognized a quarter century ago, yet their impact on host populations remains largely unresolved. By contrast, fungal and protozoan infections of dinoflagellates are well documented and generally viewed as playing major roles in host population dynamics. Our understanding of fungal parasites is largely based on studies for freshwater diatoms and dinoflagellates, although fungal infections are known for some marine phytoplankton. In freshwater systems, fungal chytrids have been linked to mass mortalities of host organisms, suppression or retardation of phytoplankton blooms, and selective effects on species composition leading to successional changes in plankton communities. Parasitic dinoflagellates of the genus Amoebophrya and the newly described Perkinsozoa, Parvilucifera infectans, are widely distributed in coastal waters of the world where they commonly infect photosynthetic and heterotrophic dinoflagellates. Recent work indicates that these parasites can have significant impacts on host physiology, behavior, and bloom dynamics. Thus, parasitism needs to be carefully considered in developing concepts about plankton dynamics and the flow of material in marine food webs.
Preferential PCR Amplification of Parasitic Protistan Small Subunit rDNA from Metazoan Tissues
Authors: BOWER SUSAN M. , CARNEGIE RYAN B. , GOH BENJAMIN , JONES SIMON R. M. , LOWE GEOFFREY J. , MAK MICHELLE W. S.
Published: July 2005

ABSTRACT. A “universal non‐metazoan” polymerase chain reaction (UNonMet‐PCR) that selectively amplifies a segment of non‐metazoan Small Subunit (SSU) rDNA gene was validated. The primers used were: 18S‐EUK581‐F (5′‐GTGCCAGCAGCCGCG‐3′) and 18S‐EUK1134‐R (5′‐TTTAAGTTTCAGCCTTGCG‐3′) with specificity provided by the 19‐base reverse primer. Its target site is highly conserved across the Archaea, Bacteria, and eukaryotes (including fungi), but not most Metazoa (except Porifera, Ctenophora, and Myxozoa) which have mismatches at bases 14 and 19 resulting in poor or failed amplification. During validation, UNonMet‐PCR amplified SSU rDNA gene fragments from all assayed protists (n = 16 from 7 higher taxa, including two species of marine phytoplank‐ton) and Fungi (n = 3) but amplified very poorly or not at all most assayed Metazoa (n = 13 from 8 higher taxa). When a non‐metazoan parasite was present in a metazoan host, the parasite DNA was preferentially amplified. For example, DNA from the parasite Trypanosoma danilewskyi was preferentially amplified in mixtures containing up to 1,000× more goldfish Carassius auratus (host) DNA. Also, the weak amplification of uninfected host (Chionoecetes tanneri) SSU rDNA did not occur in the presence of a natural infection with a parasite (Hematodinium sp.). Only Hematodinium sp. SSU rDNA was amplified in samples from infected C. tanneri. This UNonMet‐PCR is a powerful tool for amplifying SSU rDNA from non‐metazoan pathogens or symbionts that have not been isolated from metazoan hosts.
The Expression of the HSP70 Gene in Moneuplotes crassus is Controlled by a Two‐Step Process at the Transcript Level
Authors: ULLMANN JÖRG , REIDT ULRICH , KLEIN ALBRECHT
Published: July 2005

ABSTRACT. Steady state levels of the HSP70 transcript were followed by Northern hybridization in Moneuplotes crassus in order to investigate the mechanisms of the short term and long term response to heat shock in a spirotrichous ciliate. The influence of inhibitors of transcription or translation on the transcript levels was also studied. The heat shock response could be dissected into two phases. An initial protein‐dependent stabilization of the mRNA was followed by an increase of the steady state transcript level that was dependent on continued transcription. As expected, the half‐life of the RNA was short. Western blot analysis then showed that the HSP70 protein accumulated only upon permanent heat shock. It is concluded that the regulation of the heat shock response is a twostep process that occurs at the transcript level.
Isolation of a Tetrahymena thermophila Strain which Induced Metaphase I Meiotic Arrest: New Pathway of Abortive Conjugation
Authors: KACZANOWSKI ANDRZEJ , KIERSNOWSKA MAURYLA , KACZANOWSKA JANINA
Published: July 2005

ABSTRACT. A hypodiploid strain of Tetrahymena thermophila has been obtained that shows arrest at the stage of condensed nuclei, corresponding to metaphase I of normal conjugates and induced arrest at meiotic metaphase I (i.e. at the stage of condensed, bivalent chromosomes) in its wt partner mate. The metaphase I arrested conjugants retained their old macronuclei and most of them underwent cell fusion, instead of separation of exconjugants. The doublets were viable and cortically integrated. When the arrest inducing strain was crossed to the haploid tester strain, the haploid micronuclei were arrested in the meiotic metaphase I as the diploid ones had been; the monovalent, chromosomes were condensed, the arms of sister chromatids were not separated, and they were not segregated. Separation of the arms of sister chromatids and disjunction of bivalent chromosomes were not prerequisite for the formation of micro‐tubular spindles in those cells that were arrested in meiotic metaphase I. After re‐feeding, the doublet cells resumed cell divisions, segregating two macronuclei and micronuclei at random. One macronucleus was derived from the arrest inducing strain and the other from the tester strain. Heterokaryon strains with macronuclei derived from the parental arrest inducing strain and with the micronucleus derived from the parental wt tester strain were obtained. Surprisingly, these heterokaryons did not induce meiotic arrest. Thus, the arrest in the meiotic metaphase I was induced by the micronucleus and not by the macronucleus of the arrest inducing strain.
Evolutionary Origins of Hsp90 Chaperones and a Deep Paralogy in their Bacterial Ancestors
Authors: STECHMANN ALEXANDRA , CAVALIER‐SMITH THOMAS
Published: July 2005

ABSTRACT. The 82–90 kD family of molecular chaperone proteins has homologs in eukaryotes (Hsp90) and many eubacteria (HtpG) but not in Archaebacteria. We used representatives of all four different eukaryotic paralogs (cytosolic, endoplasmic reticulum (ER), chloroplast, mitochondrial) together with numerous eubacterial HtpG proteins for phylogenetic analyses to investigate their evolutionary origins. Our trees confirm that none of the organellar Hsp90s derives from the endosymbionts of early eukaryotes. Contrary to previous suggestions of distant origins through lateral gene transfer (LGT) all eukaryote Hsp90s are related to Gram‐positive eubacterial HtpG proteins. The nucleocytosolic, ER and chloroplast Hsp90 paralogs are clearly mutually related. The origin of mitochondrial Hsp90 is more obscure, as these sequences are deeply nested within eubacteria. Our trees also reveal a deep split within eubacteria into a group of mainly long‐branching sequences (including the eukaryote mitochondrial Hsp90s) and another group comprising exclusively short‐branching HtpG proteins, from which the cytosolic/ER versions probably arose. Both versions are present in several eubacterial phyla, suggesting gene duplication very early in eubacterial evolution and multiple independent losses thereafter. We identified one probable case of LGT within eubacteria. However, multiple losses can simply explain the evolutionary pattern of the eubacterial HtpG paralogs and predominate over LGT. We suggest that the actinobacterial ancestor of eukaryotes harbored genes for both eubacterial HtpG paralogs, as the actinobacterium Streptomyces coelicolor still does; one could have given rise to the mitochondrial Hsp90 and the other, following another duplication event in the ancestral eukaryote, to the cytosolic and ER Hsp90 homologs.
Age‐related differential expression of apoptosis‐related genes in conjunctival epithelial cells
Authors: Giebel Jürgen , Woenckhaus Christian , Fabian Michael , Tost Frank
Published: July 2005

Purpose:  To investigate whether the expression of apoptosis‐related genes in normal conjunctival epithelial cells is age‐related (as a prerequisite to assessing whether dysregulation of apoptosis may be involved during degenerative diseases).

Methods:  Differential expression of apoptosis‐related genes (e.g. apoptosis protease‐activating factor 1 [Apaf‐1]; caspases [casp] 3, 5, 8 and 9; Bad, Bax, Bcl‐2, Bim, c‐myc, Bag‐1, as well as p53) was assessed by reverse transcription‐polymerase chain reaction (RT‐PCR). Samples were obtained from impression cytology (IC) specimens taken from 50 healthy subjects. Group A comprised 27 subjects aged 19−32 years and group B included 23 subjects aged 53−84 years.

Results:  Reverse transcription‐PCR revealed the detection of apoptosis‐related m‐RNAs as follows (group A compared to group B): Apaf‐1 0%/0%; Bcl‐2 0%/35%; Bim 0%/9%; Bag‐1 0%/9%; p53 0%/4%; casp‐3 11%/52%; casp‐5 59%/48%; casp‐8 44%/22%; casp‐9 4%/9%; Bax 81%/52%; Bad 96%/56%, and c‐myc 89%/96%.

Conclusion:  The data show an age‐related expression of apoptosis‐related genes such as casp‐3, Bad, Bax and Bcl‐2 in normal conjunctival cells. These results provide basic information which will help us understand the expression pattern of apoptotic genes during physiological ageing of the conjunctiva and the possible dysregulation of apoptotic genes during acute and chronic diseases such as dry eye disease, allergic conjunctivitis or cicatrizing conjunctivitis.
Ptosis of submental skin
Authors: Setaro M. , Abella M. L. , Sparavigna A. , Lévêque J. L.
Published: July 2005

Background/purpose: Sagging of the face skin is a visible and unattractive characteristic of skin ageing. This phenomenon, due to both gravitational force and age‐related alterations in the mechanical properties of skin, has never been quantitatively studied. The aim of this paper was, first, to define a method and a precise procedure allowing the objective measurement of this phenomenon and, second, to study how it is related to age.

Methods: We used an electronically controlled bed that allows the comparison of submental skin profiles in both the reclined and the upright positions. A parameter that characterises the sagging amplitude for an individual was defined and the reproducibility of measurement of this parameter was verified.

Results: Results, obtained from 66 female volunteers, demonstrated a statistically significant positive correlation between this new parameter and age, and also between this new parameter and the elastic recovery parameter of skin, as measured by torquemeter.

Conclusion: Age‐related changes of the skin's mechanical properties and of the various underlying skin tissues would explain this phenomenon. This new method and procedure should allow objective evaluation of the efficacy of any treatments (cosmetic, medical or surgical) proposed for rendering the appearance of people younger.
Exploring the influence of skin perfusion on transepidermal water loss
Authors: Rodrigues Luís Monteiro , Pinto Pedro Contreiras , Magro José Martins , Fernandes Milene , Alves José
Published: July 2005

Background: Eventual relationships between the vascular function and transepidermal water loss (TEWL), in vivo, have not been entirely explored. By promoting local perfusion alterations through a well‐known challenge test, the ‘tourniquet‐cuff occlusion’ manoeuvre, the present study searches for other dynamical factors influencing the cutaneous barrier, further exploring the applicability of these flow‐related variables in dermatological research.

Methods: By applying the tourniquet‐cuff manoeuvre to a group of healthy volunteers (n=20), transcutaneous (tc) gases (pO2–pCO2), LDF (laser doppler flowmetry) and TEWL were considered as representing the dynamical aspects under study and measured non‐invasively.

Results and conclusion: An haemodynamical relationship between tcpO2 and LDF in the post‐occlusive period was clearly identified, defining the autoregulatory index as a numerical descriptor of the local metabolic‐flow adjustment under stress. TEWL was also significantly affected by the manoeuvre, especially during the post‐occlusive period, although no significant relationships between TEWL and other tc variables could be found. The present findings seem to suggest that, under the present experimental conditions, local haemodynamics may also influence TEWL measurements and the skin barrier.
Experiments on peeling adhesive tapes from human forearms
Authors: Karwoski A. C. , Plaut R. H.
Published: July 2005

Background/purpose: Peeling of adhesive tape from human skin can cause pain and trauma. The effects of the peel angle, peel rate, dwell time, subject, and order of testing were examined.

Methods: Adhesive tape was peeled from the volar forearms of four human subjects. The tape was 25.4‐mm‐wide DuraporeTM by 3M. The rates ranged from 100 to 10,000 mm/min, the peel angle from 90° to 180°, and the dwell time from one to 15 min. The tensile testing machines recorded the peel force and the displacement of the end of the tape.

Results: A range of maximum and average peel force values was observed. The peel force tended to be minimum for a peel angle around 150° in most cases. As the peel rate was increased, the peel force generally tended to increase slightly, but the relationship was erratic. As the dwell time increased, the peel force increased and then settled down. Of the subjects tested, the skin of the oldest subject experienced the most displacement and highest peel forces (the maximum force over all tests was 3.6 N). The peel force tended to increase with repeated peeling from the same skin site. Compared with peeling from a rigid substrate such as steel, the peel force from skin was lower.

Conclusion: The results improve understanding of the factors affecting the peel force, which has been correlated previously with trauma caused by peeling adhesive tape from skin.
Treatment With Cytapheresis for Antineutrophil Cytoplasmic Antibody‐associated Renal Vasculitis and Its Effect on Anti‐inflammatory Factors
Authors: Hasegawa Midori , Watanabe Asako , Takahashi Hiroki , Takahashi Kazuo , Kasugai Masami , Kawamura Nahoko , Kushimoto Hiroko , Murakami Kazutaka , Tomita Makoto , Nabeshima Kunihiro , Oohashi Atsushi , Kondou Fumiko , Ooshima Hisaji , Hiki Yoshiyuki , Sugiyama Satoshi
Published: July 2005

Abstract:  To evaluate the efficacy of cytapheresis for the treatment of rapidly progressive glomerulonephritis (RPGN) caused by myeloperoxidase antineutrophil cytoplasmic antibody (MPO‐ANCA)‐associated vasculitis, the renal prognosis and the mortality rate at 1 year after treatment were compared between a Cytapheresis Group and a Steroid Pulse Group. The Cytapheresis Group included 10 patients who were treated with cytapheresis and oral corticosteroids. Five had granulocytapheresis with the Adacolumn (Japan Immuno Research Laboratories Co. Ltd, Takasaki, Japan) and the remaining five had leukocytapheresis with the leukocyte removal filter, Cellsorba (Asahi Medical Co. Ltd, Tokyo, Japan). The Steroid Pulse Group was comprised of 12 patients who were treated with methylprednisolone pulse therapy and oral corticosteroids. In the Cytapheresis Group, renal function recovered in 70% of the patients and the mortality rate was 10%. In the Steroid Pulse Group, renal function recovered in 66.7% and the mortality rate was 33.3%, with infection as the cause of death. Total doses of corticosteroids converted to prednisolone dose during a 1 month period, ranged from 280 mg to 1226 mg in the Cytapheresis Group. On the other hand, these dosages ranged from 2375 mg to 8380 mg in the Steroid Pulse Group. These results indicated that the mortality rate by infection could be reduced by adding cytapheresis therapy. Concerning the mechanism of cytapheresis, anti‐inflammatory factors such as soluble tumor necrosis factor receptor, and interleukin‐10 reduced after cytapheresis. These changes might be responsible for the efficacy of cytapheresis. In conclusion, cytapheresis is thought to be one of the effective treatments for RPGN caused by MPO‐ANCA‐associated vasculitis, reducing the levels of anti‐inflammatory factors.
Recent Advances in Renal Phosphate Transport
Authors: Hernando Nati , Biber Jürg , Forster Ian , Murer Heini
Published: July 2005

Abstract:  Phosphate (Pi) homeostasis is achieved by adjusting the intestinal absorption and the renal excretion. Renal proximal reabsorption of Pi is regulated by controlling the amount of NaPi‐IIa cotransporters in the brush border membrane of proximal tubules. Therefore, the understanding of the molecular mechanisms that control the apical expression of NaPi‐IIa is required to have a full picture of how phosphate balancing takes place. In this review we will summarize our present knowledge about the mechanisms involved in the regulation of the apical expression and membrane retrieval of this family of transporters.
Carbonate Composite Catalyst with High-Temperature Thermal Storage for Use in Solar Tubular Reformers
Authors: Hatamachi Tsuyoshi , Kodama Tatsuya , Isobe Yuuki
Published: July 2005

The composite materials of Ni-applied, porous zirconia balls with molten Na2CO3 salt were examined for use in solar thermochemical reforming of methane as the catalyst with high-temperature thermal storage. The millimeter-sized composite balls were tested on the heat discharge property and the catalytic activity for CO2 reforming of methane in a laboratory-scale reactor. The high heat capacity and large latent heat (heat of solidification) of the composite molten salt circumvented the temperature dropping of the catalyst bed, which resulted in the alleviation of rapid decay in chemical conversion during cooling mode of the reactor. The composite catalyst is expected to realize stable operation in the solar reformer under fluctuation of insolation by a cloud passage.
Polymeric Absorbers for Flat-Plate Collectors: Can Venting Provide Adequate Overheat Protection?
Authors: Kearney Meghan , Davidson Jane , Mantell Susan
Published: July 2005

Venting and evaporative cooling are modeled as possible techniques for protecting polymer absorbers in single-glazed, flat-plate solar collectors from exceeding the material temperature limit during dry stagnation. Four venting options are considered: (I) venting above the absorber plate, (II) venting below, (III) dual venting, and (IV) venting with evaporative cooling. Results indicate that in hot, sunny conditions, venting may not provide adequate cooling to lower the absorber temperature to the relative thermal index of the polymeric materials currently in use or under consideration for this application. Venting combined with evaporative cooling from a wetted pad directly beneath the absorber plate is identified as a potential method of overheat protection in hot, dry climates.
Electromagnetic images of the Trans-Hudson orogen: the North American Central Plains anomaly revealed
Authors: Jones Alan G , Ledo Juanjo , Ferguson Ian J
Published: July 2005

Magnetotelluric studies of the Trans-Hudson orogen over the last two decades, prompted by the discovery of a significant conductivity anomaly beneath the North American Central Plains (NACP), from over 300 sites yield an extensive database for interrogation and enable three-dimensional information to be obtained about the geometry of the orogen from southern North Dakota to northern Saskatchewan. The NACP anomaly is remarkable in its continuity along strike, testimony to along-strike similarity of orogenic processes. Where bedrock is exposed, the anomaly can be associated with sulphides that were metamorphosed during subduction and compression and penetratively emplaced deep within the crust of the internides of the orogen to the boundary of the Hearne margin. A new result from this compilation is the discovery of an anomaly within the upper mantle beginning at depths of ~80100 km. This lithospheric mantle conductor has electrical properties similar to those for the central Slave craton mantle conductor, which lies directly beneath the major diamond-producing Lac de Gras kimberlite field. While the Saskatchewan mantle conductor does not directly underlie the Fort à la Corne kimberlite, which is associated with the Sask craton, the spatial correspondence is close.
Spatial and temporal variation in the influence of density dependence on growth of stream-living brown trout (Salmo trutta)
Authors: Lobón-Cerviá Javier
Published: July 2005

The objective of this study was to investigate the extent to which, and the conditions under which, density operated on growth in stream-living brown trout (Salmo trutta). Observational data of 14 cohorts at four sites of Rio Chaballos (northwestern Spain) were examined. Consistent relationships between cohort-specific mass versus cohort-specific density and between year-to-year variations in brown trout mass at the end of five successive life stages versus mean densities corroborated one another and provided compelling evidence for the occurrence of density-dependent growth. However, density-dependent patterns varied in nature among sites to the extent that they were site-specific. A further comparison among 12 data sets revealed a smooth negative power trajectory between juvenile mass versus density. This plot suggested that detection of density-dependent growth might be facilitated in low density  high growth populations located at the steep wing relative to high density  slow growth populations. Current results emphasized the importance of density as a factor determining size-at-age and supported its operation as epiphenomena capable to obscure the effects of temperature on growth. The operation of density-dependent growth on numerical regulation of the population is further discussed.
Distribution of Atlantic salmon (Salmo salar) postsmolts of different origins in the Bay of Fundy and Gulf of Maine and evaluation of factors affecting migration, growth, and survival
Authors: Lacroix Gilles L , Knox Derek
Published: July 2005

Atlantic salmon (Salmo salar) postsmolts surveyed by surface trawling in the Bay of Fundy and Gulf of Maine during 20012003 were aggregated in several areas in the Bay of Fundy and dispersed over a broader area in the Gulf of Maine. Postsmolt distribution reflected the major surface-current vectors and was independent of origin (wild vs. hatchery, inner vs. outer Bay of Fundy). Migration proceeded without disruption, and marked wild postsmolts from both the inner and outer Bay of Fundy were recaptured in the outer Bay of Fundy and the Gulf of Maine, where their distribution overlapped the commercial fishery for Atlantic herring (Clupea harengus). Marked postsmolts of wild origin were recaptured more frequently than those of hatchery origin but the overall density was low, and no schools of postsmolts were encountered that could offer protection from predators. Temperature and salinity in postsmolt habitat were favourable for growth and survival. Postsmolts were in excellent condition and had no bacterial or viral pathogens or salmon lice (Lepeophtheirus salmonis). They were feeding on pelagic prey (amphipods, euphausiids, and fish larvae) and the period of accelerated marine growth had started, indicating that environmental conditions and food supply were not limiting growth and survival.
Interactions of productivity, predation risk, and fishing effort in the efficacy of marine protected areas for the central Pacific
Authors: Martell Steven J.D. , Essington Timothy E , Lessard Bob , Kitchell James F , Walters Carl J , Boggs Christofer H
Published: July 2005

Ecospace biomass-dynamics models for the central North Pacific predict strong space-time variation in abundances of various trophic groups in relation to nutrient-driven patterns in primary production and circulation-driven concentration of production in convergence areas. The model predicts simple patterns in ecosystem organization and abundances along productivity gradients. Predicted patterns are robust to alternative assumptions about how mobile organisms may alter dispersal behavior in relation to local fitness (per capita gain from net food intake minus predation mortality). Large marine protected areas (MPAs) would be needed to rebuild endangered populations and counter impacts of growing fishing effort. We expected that increases in dispersal rate in response to lower food availability and higher predation risk would reduce efficacy of MPAs as a management tool. Instead, simulations indicated that this negative effect may generally be eliminated or even reversed by positive effects of fitness-maximizing behaviors. Interannual variability in ocean circulation can further reduce the efficacy of MPAs; therefore, the dynamic nature of pelagic environments should also be considered in MPA design. Anomalies in ocean circulation may shift productive areas relative to MPA location, resulting in increased fishing mortality and (or) misinterpretation of catch statistics.
Oblate skyrmions with B=2
Authors: Marleau L , Rivard J -F
Published: July 2005

The numerical solution for the B = 2 static soliton of the SU(2) Skyrme model shows a profile-function dependence that is not exactly radial. We quantify this by introducing an axially symmetric oblate solution parametrized with a scale factor d. We then obtain a relatively deformed bound-soliton configuration with MB=2/MB=1 = 1.958. This is the first step toward the description of B = 2 quantized states, such as the deuteron, with a nonrigid oblate Ansatz, for which deformations due to centrifugal effects are expected to become important.PACS Nos.: 11.25.Mj, 13.85.Qk
SYSTEMATIC STUDY ON EXACTLY SOLVABLE TRIGONOMETRIC POTENTIALS WITH PT SYMMETRY
Authors: JIA CHUN-SHENG , YI LIANG-ZHONG , ZHAO XING-QIANG , LIU JIAN-YI , SUN LIANG-TIAN
Published: July 2005

We propose a unified treatment of generating exactly solvable trigonometric potentials with PT symmetry. Our symmetric approach reproduces a number of earlier results. We show that the energy spectra for the exactly solvable PT-symmetric trigonometric potentials can be obtained from a general energy spectrum formula.
STABLE CONTINUOUS SPECTRA FOR DIFFERENTIAL OPERATORS OF ARBITRARY ORDER
Authors: BARO M. , DEMUTH M. , GIERE E.
Published: July 2005

Perturbations of the continuous spectra of two self-adjoint operators H0 and H can be controlled by sandwiched differences of the form [Formula: see text] where ϕj(·) are bounded functions of the operators involved.

If ϕj(H0) and ϕj(H) are integral operators, we give general integral conditions for the kernels, such that the continuous, the absolutely continuous and the singular continuous spectra of H0 and H coincide.

The abstract operator theoretical conditions are applied for H0 in L 2(ℝd) of the form (-Δ)α/2, α∈ (0,2) and (-Δ)m, m∈ℕ. H is given as a perturbation of H0, where we allow perturbations by variable coefficients, potentials or obstacles.
BOTANICAL INSECTICIDES, DETERRENTS, AND REPELLENTS IN MODERN AGRICULTURE AND AN INCREASINGLY REGULATED WORLD
Authors: Isman Murray B.
Published: July 2005

▪ Abstract  Botanical insecticides have long been touted as attractive alternatives to synthetic chemical insecticides for pest management because botanicals reputedly pose little threat to the environment or to human health. The body of scientific literature documenting bioactivity of plant derivatives to arthropod pests continues to expand, yet only a handful of botanicals are currently used in agriculture in the industrialized world, and there are few prospects for commercial development of new botanical products. Pyrethrum and neem are well established commercially, pesticides based on plant essential oils have recently entered the marketplace, and the use of rotenone appears to be waning. A number of plant substances have been considered for use as insect antifeedants or repellents, but apart from some natural mosquito repellents, little commercial success has ensued for plant substances that modify arthropod behavior. Several factors appear to limit the success of botanicals, most notably regulatory barriers and the availability of competing products (newer synthetics, fermentation products, microbials) that are cost-effective and relatively safe compared with their predecessors. In the context of agricultural pest management, botanical insecticides are best suited for use in organic food production in industrialized countries but can play a much greater role in the production and postharvest protection of food in developing countries.
The Social Psychology of Health Disparities
Authors: Schnittker Jason , McLeod Jane D.
Published: July 2005

In recent years, scholars from a variety of disciplines have turned to the potential psychosocial determinants of health in pursuit of an explanation for socioeconomic and racial/ethnic disparities. This review discusses the literature on psychosocial factors and mental and physical health, focusing on the roles of subjective status, self/identity, and perceived discrimination. We argue that current research may have obscured important social psychological considerations and that it is an opportune time to reconsider the social psychology of disparities. A social psychology of disparities could provide a bridge between those who encourage research on health's “upstream” causes and those who encourage research on “downstream” mechanisms precisely because social psychology is concerned with the vast “meso” level of analysis that many allude to but few explicitly traverse. We point to the importance of person-environment interactions, contingencies, reciprocality, and meaning. Although psychosocial factors might not explain disparities in the manner much psychosocial research would seem to suggest, psychosocial factors are important causes in their own right and, when considered in a more sophisticated social psychological light, may help to refine disparities theory and research.
The Social Consequences of Structural Adjustment: Recent Evidence and Current Debates
Authors: Babb Sarah
Published: July 2005

Thirty years ago, intellectual debates concerning the relationship between wealthy and poor nations could be summed up under the rubric of modernization versus dependency. However, the events of the 1980s and 1990s completely shifted the terms of this debate. Associated with the structural adjustment lending programs of the World Bank and International Monetary Fund, and neoliberal ideology, a new policy discourse suggested that it was only through liberating market forces that poor countries could grow and catch up to the developed world. With 20 years of structural adjustment behind us, what does the evidence suggest about the social consequences of these policies? This review focuses on three different social transformations: changes in the governance of economies, transformations in class structures, and the rise of transnational networks.
Quasicoincidence for intuitionistic fuzzy points
Authors: Lupiáñez Francisco Gallego
Published: July 2005

The introduction of intuitionistic fuzzy sets is due to K. T. Atanassov, who also proposed some problems about this subject. D. Çoker defined the intuitionistic fuzzy topological spaces and, with some coworkers, studied these spaces. In this paper, we define and study the notion of quasicoincidence for intuitionistic fuzzy points and obtain a characterization of continuity for maps between intuitionistic fuzzy topological spaces
Semidiscretization for a nonlocal parabolic problem
Authors: El Hachimi Abderrahmane , Sidi Ammi Moulay Rchid
Published: July 2005

A time discretization technique by Euler forward scheme is proposed to deal with a nonlocal parabolic problem. Existence and uniqueness of the approximate solution are proved.
Automated Selection of Appropriate Pheromone Representations in Ant Colony Optimization
Authors: Montgomery James , Randall Marcus , Hendtlass Tim
Published: July 2005

Ant colony optimization (ACO) is a constructive metaheuristic that uses an analogue of ant trail pheromones to learn about good features of solutions. Critically, the pheromone representation for a particular problem is usually chosen intuitively rather than by following any systematic process. In some representations, distinct solutions appear multiple times, increasing the effective size of the search space and potentially misleading ants as to the true learned value of those solutions. In this article, we present a novel system for automatically generating appropriate pheromone representations, based on the characteristics of the problem model that ensures unique pheromone representation of solutions. This is the first stage in the development of a generalized ACO system that could be applied to a wide range of problems with little or no modification. However, the system we propose may be used in the development of any problem-specific ACO algorithm.
Emergent Patterning Phenomena in 2D Cellular Automata
Authors: Bilotta Eleonora , Pantano Pietro
Published: July 2005

This article discusses mechanisms of pattern formation in 2D, self-replicating cellular automata (CAs). In particular, we present mechanisms for structure replication that provide insight into analogous processes in the biological world. After examining self-replicating structures and the way they reproduce, we consider their fractal properties and scale invariance. We explore the space of all possible mutations, showing that despite their apparent differences, many patterns produced by CAs are based on universal models of development and that mutations may lead either to stable or to unstable development dynamics. An example of this process for all possible one-step mutations of one specific CA is given. We have demonstrated that a self-replicating system can carry out many slightly different but related entities, realizing new different growth models. We infer that self-replicating systems exist in an intermediate regime between order and chaos, showing that these models degrade into chaotic configurations, passing through a series of transition stages. This process is quantified by measuring the Hamming distances between the pattern produced by the original self-replicator and those produced by mutated systems. The analysis shows that many different mechanisms may be involved in patterning phenomena. These include changes in the external or internal layers of the structure, substitution of elements, differential rates of growth in different parts of the structure, structural modifications, changes in the original model, the emergence of different structures governed by different CA rules, and changes in the self-replication process.
Evolution of DNA Uptake Signal Sequences
Authors: Chu Dominique , Lee Hoong-Chien , Lenaerts Tom
Published: July 2005

The DNA of some naturally competent species of bacteria contains a large number of evenly distributed copies of a short sequence. This highly overrepresented sequence is believed to be an uptake signal sequence (USS) that helps bacteria to take up DNA selectively from (dead) members of their own species. For some time it has been assumed that the USS evolved in order to enable bacteria to distinguish between conspecific and nonconspecific DNA fragments (the preference-first hypothesis). Recently, Redfield suggested that this hypothesis is not in fact realistic, as it would require biologically implausible group selection. In this article we present a model designed to demonstrate the emergence of similar USSs in a population of simulated evolving agents. We use this model to examine the conditions under which a USS will emerge in a preference-first scenario.