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41.
Ingrid Elise Amlie Hegertun Kristin Marie Sulheim Gundersen Elisabeth Kleppa Siphosenkosi Gift Zulu Svein Gunnar Gundersen Myra Taylor Jane D. Kvalsvig Eyrun Floerecke Kjetland 《PLoS neglected tropical diseases》2013,7(3)
Background
Schistosoma (S.) haematobium infection is a common cause of genital morbidity in adult women. Ova in the genital mucosal lining may cause lesions, bleeding, pain, discharge, and the damaged surfaces may pose a risk for HIV. In a heterogeneous schistosomiasis endemic area in South Africa, we sought to investigate if young girls had genital symptoms and if this was associated with urinary S. haematobium.Methodology
In a cross-sectional study of 18 randomly chosen primary schools, we included 1057 schoolgirls between the age of 10 and 12 years. We interviewed assenting girls, whose parents had consented to their participation and examined three urines from each of them for schistosome ova.Principal findings
One third of the girls reported to have a history of genital symptoms. Prior schistosomal infection was reported by 22% (226/1020), this was associated with current genital symptoms (p<0.001). In regression analysis the genital symptoms were significantly associated both with urinary schistosomiasis (p<0.001) and water contact (p<0.001).Conclusions
Even before sexually active age, a relatively large proportion of the participating girls had similar genital symptoms to those reported for adult genital schistosomiasis previously. Anti-schistosomal treatment should be considered at a young age in order to prevent chronic genital damage and secondary infections such as HIV, sexually transmitted diseases and other super-infections. 相似文献42.
The genus Phlomis is one of the largest genera of subfamily Lamioideae (Lamiaceae) with more than 100 recognised species distributed in Asia,
southern Europe and northern Africa. Morphological studies have suggested that the species can be split into two morphologically
distinct groups that have previously been recognised as either sections or separate genera. The current study represents the
first molecular phylogenetic study of the genus in which taxa representative of the entire genus are included. In contrast
to considerable morphological and ecological variation among taxa, sequence variation in the trnL intron, the trnL – F intergenic spacer, and the rps16 intron was low, resulting in sparse phylogenetic resolution, particularly among the South West Asian and Mediterranean taxa.
However, the results support a split of the genus into two separate groups that are recognised here as the genera Phlomoides and Phlomis in order to decrease taxonomic complexity. The close relationship between Phlomis s.l. and Eremostachys, pointed out by several authors, is confirmed, and in a noteworthy new finding, the small Asian genus Notochaete, is more closely related to the Phlomis s.l. lineage than previously assumed. The two monotypic genera Pseuderemostachys and Lamiophlomis as well as Notochaete hamosa are transferred to Phlomoides and three new combinations are made. Character optimisation analyses based on geographic distributions of all taxa show that
the groups obtained by molecular phylogenetic analysis correlate well with biogeography. The results suggest that the Phlomis s.l. lineage has a Central Asian origin in an area around Western China. 相似文献
43.
Moen MN Knævelsrud I Haugland GT Grøsvik K Birkeland NK Klungland A Bjelland S 《Journal of bacteriology》2011,193(17):4495-4508
Hydrolytic deamination of cytosine to uracil in DNA is increased in organisms adapted to high temperatures. Hitherto, the uracil base excision repair (BER) pathway has only been described in two archaeons, the crenarchaeon Pyrobaculum aerophilum and the euryarchaeon Archaeoglobus fulgidus, which are hyperthermophiles and use single-nucleotide replacement. In the former the apurinic/apyrimidinic (AP) site intermediate is removed by the sequential action of a 5'-acting AP endonuclease and a 5'-deoxyribose phosphate lyase, whereas in the latter the AP site is primarily removed by a 3'-acting AP lyase, followed by a 3'-phosphodiesterase. We describe here uracil BER by a cell extract of the thermoacidophilic euryarchaeon Thermoplasma acidophilum, which prefers a similar short-patch repair mode as A. fulgidus. Importantly, T. acidophilumcell extract also efficiently executes ATP/ADP-stimulated long-patch BER in the presence of deoxynucleoside triphosphates, with a repair track of ~15 nucleotides. Supplementation of recombinant uracil-DNA glycosylase (rTaUDG; ORF Ta0477) increased the formation of short-patch at the expense of long-patch repair intermediates, and additional supplementation of recombinant DNA ligase (rTalig; Ta1148) greatly enhanced repair product formation. TaUDG seems to recruit AP-incising and -excising functions to prepare for rapid single-nucleotide insertion and ligation, thus excluding slower and energy-costly long-patch BER. 相似文献
44.
Svein Løkkeborg Sten Ivar Siikavuopio Odd-Børre Humborstad Anne Christine Utne-Palm Keno Ferter 《Reviews in Fish Biology and Fisheries》2014,24(4):985-1003
Better knowledge of food search behaviour in fish is essential for studies that aim to improve longline fishing, particularly through bait development. This review provides an overview of our understanding of how fish detect and locate sources of food odour, focusing on the stimuli and sensory modalities involved, and on factors that affect feeding activity. Studies that identify feeding attractants and efforts to develop alternative longline baits are presented. The review reveals that such studies are few in number, and that to date there are no alternatives to traditional baits in commercial longlining despite the growing demand for these resources, which are also used for human consumption. The chemical compounds that elicit food search behaviour differ from species to species, and species selectivity could be improved by incorporating specific feeding attractants in manufactured baits. The unique properties of chemical stimuli and odour dispersal form the basis for improving longline efficiency through the development of a long-lasting bait. Vision is important in prey capture, and manufactured baits can be made more visible than natural baits by increasing the contrast (e.g. via fluorescent or polarising coatings) and creating motion through buoyancy. Physical properties such as size, shape, texture and strength can also be manipulated in a manufactured bait to improve catch efficiency. Knowledge obtained from studies of various aspects of food search behaviour is of paramount importance for future research aimed at alternative bait development and improving longline fishing. 相似文献
45.
Objectives
This 40-week workplace physical training RCT investigated the effect of soccer and Zumba, respectively, on muscle pain intensity and duration, work ability, and rating of perceived exertion (RPE) during work among female hospital employees.Methods
107 hospital employees were cluster-randomized into two training groups, and a control group. The training was conducted outside working hours as two-three 1-h sessions per week for the first 12 weeks, and continued as one-two 1-h sessions per week for the last 28 weeks. Muscle pain intensity and duration, work ability, and RPE during work were measured at baseline and after 12 and 40 weeks.Results
After 12 weeks, both the soccer (−1.9, 95% CI, −3.0, −0.8, P = 0.001) and the Zumba group (−1.3, 95% CI, −2.3, −0.3, P = 0.01) reduced the pain intensity (on a scale from 0 to 10) in the neck-shoulder region (eta squared = 0.109), whereas only the soccer group (−1.9, 95% CI, −3.2, −0.7, P = 0.002, eta squared = 0.092) showed a reduction after 40 weeks referencing the control group. After 40 weeks, both the soccer (-16.4 days, 95% CI, −29.6, −3.2, P<0.02) and the Zumba group (-16.6 days, 95% CI, −28.9, −4.2, P<0.01) reduced the pain duration during the past 3 months in the neck-shoulder region (eta squared = 0.077). No significant effects on intensity or duration of pain in the lower back, RPE during work or work ability were found.Conclusions
The present study indicates that workplace initiated soccer and Zumba training improve neck-shoulder pain intensity as well as duration among female hospital employees.Trial Registration
International Standard Randomized Controlled Trial Number Register ISRCTN 61986892. 相似文献46.
Ingibjörg E. Einarsdóttir Kjell J. Nilssen Svein O. Øren Martin Iversen 《Polar Biology》2000,23(4):231-235
In order to elucidate the immune responses of Arctic charr in relation to temperature, groups were acclimated to a moderate
(9°C) and a cold temperature regime (4°C), as well as subjected to a temperature decrease (from 9 to 4°C) immediately prior
to an immunization with sheep red blood cells. The charr kept at 9°C responded with increased primary and secondary antibody
titres, as seen by direct haemagglutination, while fish at 4°C, as well as the fish subjected to a temperature reduction,
displayed lower and lowest antibody titres, respectively, and only after a second immunization. It is concluded that Arctic
charr can respond to a cellular antigen with a humoral immune response typical for other teleosts, but that the immune response
is delayed and diminished at low temperatures. This temperature-induced immune suppression is intensified if the fish have
not been acclimated to cold water prior to immunization.
Accepted: 10 October 1999 相似文献
47.
The red king crab (Paralithodes camtschaticus) was introduced in the Barents Sea in the 1960s and soon established a viable population. Proper management and exploitation
of the Barents Sea king crab stock require better understanding of the spatial dynamics at different scales. This study examines
the small-scale movement patterns of seven adult male crabs tracked for a period of up to one month from mid July to mid August
at 150 m depth in a semi-enclosed fjord on the Russo-Norwegian border. The crabs were tagged with acoustic transmitters and
their movements monitored with an acoustic positioning system. Low walking speeds (<0.01 m s−1) were most frequent but the crabs could move at a maximum speed of 0.15 m s−1 and walk an actual distance of up to 270 m over a period of one hour. However, the crabs usually moved within a relatively
restricted area with mean hourly longest rectilinear distance varying from 26 to 64 m. The crabs alternated between periods
of low and high activity, which could reflect feeding in and movements between food patches. The lack of a diel activity rhythm
may be due to high light levels during the polar summer night, or a chemically mediated food search strategy. 相似文献
48.
Gerd Svenneby Bjørg Roberg Svein Hogstad Ingeborg Aa. Torgner Elling Kvamme 《Journal of neurochemistry》1986,47(5):1351-1355
The kinetics and other properties of phosphate-activated glutaminase have for the first time been studied in the crude mitochondrial fraction (P2 fraction) from human brain. The enzyme is for unexplained reasons inactivated postmortem. The enzyme activity decreases by storing the tissue or homogenate at 37 degrees C. The inactivation is not caused by formation of a dialysable inhibiting compound. No large proteolytic degradation has occurred, since the phosphate-activated glutaminase-like immunoreactive band did not disappear during the storage. The molecular weight of the subunit of the enzyme as determined by immunoblots of sodium dodecyl sulfate-treated homogenates from human brain is estimated to be approximately 64 K. The enzyme has been shown to have a pH optimum of 8.6; it is activated by phosphate, inhibited by glutamate, and partially inhibited by ammonia. Double-inverse plots of enzyme activity against phosphate are concave-upward, and more so in the presence of an inhibitor. The inhibition by glutamate appears to be noncompetitive with the substrate glutamine, and competitive with the activator phosphate. These kinetic properties are not significantly different from our earlier observations concerning phosphate-activated glutaminase from pig brain and pig kidney. 相似文献
49.
Nielsen SB Yde P Giehm L Sundbye S Christiansen G Mathiesen J Jensen MH Jensen PH Otzen DE 《Journal of molecular biology》2012,421(4-5):601-615
The 219-residue protein p25α stimulates the fibrillation of α-synuclein (αSN) in vitro and colocalizes with it in several α-synucleinopathies. Although p25α does not fibrillate by itself under native conditions in vitro, αSN-free p25α aggregates have also been observed in vivo in, for example, multiple system atrophy. To investigate which environmental conditions might trigger this aggregation, we investigated the effect of polyanionic biomolecules on p25α aggregation. Heparin, polyglutamate, arachidonic acid micelles, and RNA all induce p25α aggregation. More detailed studies using heparin as template for aggregation reveal that a minimum of 10-14 heparin monosaccharide units per heparin polymer are required. Bona fide fibrils are only formed at intermediate heparin concentrations, possibly because an excess of heparin binding sites blocks the inter-p25α contacts required for amyloid formation. Other polyanions also show an optimum for amyloid formation. Aggregation involves only modest structural changes according to both spectroscopic and proteolytic experiments. The aggregates do not seed aggregation of heparin-free p25α, suggesting that heparin is required in stoichiometric amounts to form organized structures. We are able to reproduce these observations in a model involving two levels of binding of p25α to heparin. We conclude that the modest structural changes that p25α undergoes can promote weak intermolecular contacts and that polyanions such as heparin play a central role in stabilizing these aggregates but in multiple ways, leading to different types of aggregates. This highlights the role of non-protein components in promoting protein aggregation in vivo. 相似文献
50.
Sren Toft Elsa Cuende Astrid Louise Olesen Anne Mathiesen Maria Meisner Larsen Kim Jensen 《Oikos》2019,128(10):1467-1477
Habitats vary in food resources with carnivores often being prey limited, but it is unclear whether habitats facilitate a nutritionally balanced diet. Two paradigms in nutritional ecology, ecological stoichiometry and nutritional geometry, predict that carnivores are limited mainly by protein or lipid, respectively. Using the carabid beetle Anchomenus dorsalis and 10 other predatory beetles from agricultural fields, we developed and tested two simple procedures for quantifying macronutrient‐specific habitat conditions without requiring information about the natural prey. Both procedures assume that predators forage for nutrients rather than specific prey. Our results show that 10 of 11 species were food limited. Five species were lipid limited and one species was protein limited in the field. Co‐existing predator species showed considerable segregation of fundamental macronutritional niches. A linear relationship between specific nutrient limitation and the target lipid:protein (L:P) intake ratio indicates that species with high L:P target are more protein limited while species with low L:P target are more lipid limited. The study illustrates how species within a natural assemblage vary in nutritional niche and in specific nutrient limitation. 相似文献