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51.
52.
Akira F. Peters Madeleine J. H. van Oppen Christian Wiencke Wytze T. Stam Jeanine L. Olsen 《Journal of phycology》1997,33(2):294-309
Phylogenetic relationships in the Desmarestiales (Phaeophyceae) were inferred among the monotypic Arthrocladia (Arthrocladiaceae) and 27 isolates from Desmarestiaceae, representing 17 taxa of Desmarestia and the monotypic Antarctic genera Himantothallus and Phaeurus. Phaeurus and Arthrocladia were used as outgroups. Parsimony analyses of nuclear ribosomal DNA internal transcribed spacer (ITS1 and ITS2) sequences, in which gaps were both included and excluded, yielded well-resolved trees with a consistent general branching pattern. A parallel analysis of nine morphological and life-history characters and three ecological characters yielded a similar tree but provided little resolution in the terminal clades. The position of the monotypic Arthrocladia villosa within the Desmarestiales is consistent with monophyly for the order, but its position as the most primitive desmarestialean is not resolvable from the molecular data set. The basal position of Phaeurus, the Antarctic Desmarestia species, and Himantothallus is consistent with the hypothesis of a Southern Hemisphere origin for the family Desmarestiaceae. The more recent Northern Hemisphere “aculeata” clade evolved from an Antarctic ancestor. A “D. aculeata-like” species was ancestral to a lineage characterized by annual sporophytes with high sulfuric acid content, which radiated into many species, widely distributed in both hemispheres. Mapping of morphological and ecological characters onto the molecular tree confirm the informativeness of sulfuric acid-containing vacuoles and unilocular sporangial types. There is good congruence between phylogenetic tree topology and temperature impints in relation to biogeographic distribution, supporting the theory that temperature tolerance is a conservative trait. 相似文献
53.
Aprilianto E. Wiria Firdaus Hamid Linda J. Wammes Maria M. M. Kaisar Linda May Margaretta A. Prasetyani Sitti Wahyuni Yenny Djuardi Iwan Ariawan Heri Wibowo Bertrand Lell Robert Sauerwein Gary T. Brice Inge Sutanto Lisette van Lieshout Anton J. M. de Craen Ronald van Ree Jaco J. Verweij Roula Tsonaka Jeanine J. Houwing-Duistermaat Adrian J. F. Luty Erliyani Sartono Taniawati Supali Maria Yazdanbakhsh 《PloS one》2013,8(3)
Background
Helminth infections are proposed to have immunomodulatory activities affecting health outcomes either detrimentally or beneficially. We evaluated the effects of albendazole treatment, every three months for 21 months, on STH, malarial parasitemia and allergy.Methods and Findings
A household-based cluster-randomized, double-blind, placebo-controlled trial was conducted in an area in Indonesia endemic for STH. Using computer-aided block randomization, 481 households (2022 subjects) and 473 households (1982 subjects) were assigned to receive placebo and albendazole, respectively, every three months. The treatment code was concealed from trial investigators and participants. Malarial parasitemia and malaria-like symptoms were assessed in participants older than four years of age while skin prick test (SPT) to allergens as well as reported symptoms of allergy in children aged 5–15 years. The general impact of treatment on STH prevalence and body mass index (BMI) was evaluated. Primary outcomes were prevalence of malarial parasitemia and SPT to any allergen. Analysis was by intention to treat. At 9 and 21 months post-treatment 80.8% and 80.1% of the study subjects were retained, respectively. The intensive treatment regiment resulted in a reduction in the prevalence of STH by 48% in albendazole and 9% in placebo group. Albendazole treatment led to a transient increase in malarial parasitemia at 6 months post treatment (OR 4.16(1.35–12.80)) and no statistically significant increase in SPT reactivity (OR 1.18(0.74–1.86) at 9 months or 1.37 (0.93–2.01) 21 months). No effect of anthelminthic treatment was found on BMI, reported malaria-like- and allergy symptoms. No adverse effects were reported.Conclusions
The study indicates that intensive community treatment of 3 monthly albendazole administration for 21 months over two years leads to a reduction in STH. This degree of reduction appears safe without any increased risk of malaria or allergies.Trial Registration
Controlled-Trials.com ISRCTN83830814 相似文献54.
Cheek AO King VW Burse JR Borton DL Sullivan CV 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2004,137(3):249-260
Vitellogenin (VTG) is a highly specific marker of exposure to environmental estrogens and has been used extensively in field and laboratory studies of estrogenic endocrine disruption in fishes. The purpose of this study was to develop and validate a sensitive, competitive, enzyme-linked immunosorbent assay (ELISA) specific for bluegill (Lepomis macrochirus) vitellogenin. Bluegill VTG was purified by anion exchange chromatography on DEAE-agarose. The polypeptide had an apparent mass of 170 kDa and was specifically recognized by the rabbit antiserum raised against bluegill female-specific plasma protein. Plasma samples from vitellogenic females diluted in parallel with the purified VTG standard curve in the ELISA. The detection limit of the assay was 29 ng/ml and the working range extended to 2700 ng/ml. Recovery of purified VTG was 85.8+/-9.5%, intra-assay variation was 6.4% and interassay variation was 12.3%. We used this ELISA to analyze the seasonal cycle of vitellogenesis in female bluegill and to evaluate potential disruption of this process by exposure to bleached kraft mill effluent (BKME). Captive female bluegill stocked in outdoor experimental streams in New Bern, NC had the lowest levels of VTG, estradiol-17beta (E2), and testosterone (T) and the smallest oocyte diameters in January, but these variables increased in March and remained elevated through August, suggesting an extended spawning season. Plasma VTG, E2, T and oocyte diameter were unaffected by exposure to BKME concentrations as high as 30%. Development of the VTG ELISA allowed rapid and convenient analysis of plasma samples to evaluate exposure to potential endocrine disrupting compounds. 相似文献
55.
Jeanine A Verbunt Henk AM Seelen Feljandro P Ramos Bernard HM Michielsen Wim L Wetzelaer Martine Moennekens 《BMC neurology》2008,8(1):7
Background
Over 50% of patients with upper limb paresis resulting from stroke face long-term impaired arm function and ensuing disability in daily life. Unfortunately, the number of effective treatments aimed at improving arm function due to stroke is still low. This study aims to evaluate a new therapy for improving arm function in sub-acute stroke patients based on mental practice theories and functional task-oriented training, and to study the predictors for a positive treatment result. It is hypothesized that a six-week, mental practice-based training program (additional to regular therapy) targeting the specific upper extremity skills important to the individual patient will significantly improve both arm function and daily activity performance, as well as being cost effective. 相似文献56.
Reger TS Yang ZQ Schlegel KA Shu Y Mattern C Cube R Rittle KE McGaughey GB Hartman GD Tang C Ballard J Kuo Y Prueksaritanont T Nuss CE Doran SM Fox SV Garson SL Li Y Kraus RL Uebele VN Renger JJ Barrow JC 《Bioorganic & medicinal chemistry letters》2011,21(6):1692-1696
A novel series of amide T-type calcium channel antagonists were prepared and evaluated using in vitro and in vivo assays. Optimization of the screening hit 3 led to identification of the potent and selective T-type antagonist 37 that displayed in vivo efficacy in rodent models of epilepsy and sleep. 相似文献
57.
Kyle T. Gagnon Elizabeth A. Cashdan Jeanine K. Stefanucci Sarah H. Creem-Regehr 《Human nature (Hawthorne, N.Y.)》2016,27(1):82-97
Venturing into novel terrain poses physical risks to a female and her offspring. Females have a greater tendency to avoid physical harm, while males tend to have larger range sizes and often outperform females in navigation-related tasks. Given this backdrop, we expected that females would explore a novel environment with more caution than males, and that more-cautious exploration would negatively affect navigation performance. Participants explored a novel, large-scale, virtual environment in search of five objects, pointed in the direction of each object from the origin, and then navigated back to the objects. We found that females demonstrated more caution while exploring as reflected in the increased amounts of pausing and revisiting of previously traversed locations. In addition, more pausing and revisiting behaviors led to degradation in navigation performance. Finally, individual levels of trait harm avoidance were positively associated with the amount of revisiting behavior during exploration. These findings support the idea that the fitness costs associated with long-distance travel may encourage females to take a more cautious approach to spatial exploration, and that this caution may partially explain the sex differences in navigation performance. 相似文献
58.
NF Gallardo-Romero CP Drew SL Weiss MG Metcalfe YJ Nakazawa SK Smith GL Emerson CL Hutson JS Salzer JH Bartlett VA Olson CJ Clemmons WB Davidson SR Zaki KL Karem IK Damon DS Carroll 《PloS one》2012,7(8):e43881
Volepox virus (VPXV) was first isolated in 1985 from a hind foot scab of an otherwise healthy California vole (Microtus californicus). Subsequent surveys in San Mateo County, CA, revealed serological evidence suggesting that VPXV is endemic to this area, and a second viral isolate from a Pinyon mouse (Peromyscus truei) was collected in 1988. Since then, few studies have been conducted regarding the ecology, pathology, and pathogenicity of VPXV, and its prevalence and role as a potential zoonotic agent remain unknown. To increase our understanding of VPXV disease progression, we challenged 24 California mice (Peromyscus californicus) intranasally with 1.6×10(3) PFU of purified VPXV. By day five post infection (pi) we observed decreased activity level, conjunctivitis, ruffled hair, skin lesions, facial edema, and crusty noses. A mortality rate of 54% was noted by day eight pi. In addition, internal organ necrosis and hemorrhages were observed during necropsy of deceased or euthanized animals. Viral loads in tissues (brain, gonad, kidney, liver, lung, spleen, submandibular lymph node, and adrenal gland), bodily secretions (saliva, and tears), and excretions (urine, and/or feces) were evaluated and compared using real time-PCR and tissue culture. Viral loads measured as high as 2×10(9) PFU/mL in some organs. Our results suggest that VPXV can cause extreme morbidity and mortality within rodent populations sympatric with the known VPXV reservoirs. 相似文献
59.
Two human single chain variable fragment (scFv) libraries were used to select clones that bound to the surface glycoprotein S16 of Cryptosporidium parvum. Panning of the Tomlinson libraries I and J resulted in the isolation of nine distinct clones. Of the four clones which had full-length scFv, three contained stop codons. The remaining five clones were truncated, with four missing the heavy chain, and one missing most of the light chain. The full-length clones exhibited better binding to native C. parvum proteins and recombinant S16 than the truncated clones, with the exception of one truncated clone. None of the selected clones cross-reacted with Giardia lamblia, Escherichia coli, Streptococcus pyogenes, Listeria monocytogenes, Bacillus cereus or another immunogenic target of C. parvum, P23. Clones expressed as the soluble scFv-gIIIp construct were able to detect C. parvum native proteins and sporozoites. Panning from naïve libraries was an useful method for isolation and identification of recombinant antibodies that have the potential for use in pathogen detection and immunotherapy. 相似文献
60.
Jeanine Brederoo Piet de Wildt Corrie Popp-Snijders Robin F. Irvine Alan Musgrave Herman van den Ende 《Planta》1991,184(2):175-181
InChlamydomonas eugametos gametes, phosphatidylinositol 4-phosphate (PtdInsP) and phosphatidylinositol 4,5-bisphosphate (PtdInsP2) comprised 0.4 and 0.3% of the whole-cell phospholipids. They were concentrated in the plasma membrane around the cell body and were present in low concentrations in the flagellar membrane. When gametes were fed32PO
4
-
, the label was rapidly incorporated into PtdInsP and PtdInsP2 and only slowly incorporated into structural lipids such as phosphatidylethanolamine and phosphatidylglycerol. Similarly, when a pulse of32PO
4
-
was chased with PO
4
-
, the label was rapidly lost from the polyphosphoinositol lipids but not from the structural lipids. The major fatty acids in the polyphosphoinositides were C-22 carbon polyenoic acids (70%). The significance of these results in relationship to intracellular signalling via inositol phosphates and Ca2+ is discussed.Abbreviations InsP3
inositol 1,4,5-trisphosphate
- mt–/mt+
mating-type plus or minus
- PtdA
phosphatidic acid
- PtdEtn
phosphatidylethanolamine
- PtdGro
phosphatidylglycerol
- PtdIns
phosphatidylinositol
- PtdInsP
phosphatidylinositol 4-phosphate;
- PtdInsP2
phosphatidylinositol 4,5-bisphosphate
- TCA
trichloroacetic acid
We thank Frank Schuring for Fig. 5A and Susan Kenter, Hans Kruisselbrink, Saskia Bijvank and Nelleke Corbett for their enthousiastic assistance. 相似文献