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An account is given of the morphology and the taxonomy of the Asian, Australian and Pacific genus Archidendron (Leguminosae – Mimosoideae). A new infrageneric classification based on morphological data is presented, the genus being subdivided in 8 series. The phylogeny of the genus is discussed, the base of discussion being all available morphological, palynological and wood–anatomical characters. The presence/absence of stipules, the length of the staminal tube compared with that of the corolla–tube, the sessile/stipitate ovary(–ies), the morphology of the pods and the wood–anatomy have been particularly useful in determining the evolutionary trends within the genus. Analyses of the geographical range of selected character states are presented. The data suggest a Central – W. Malesian origin of the genus. The series endemic to the E. Malesian – Australian area have probably evolved more recently. The pluricarpellate condition of the flowers in several species endemic to the E. Malesian and Australian area is considered to be a derived character state. The following new taxa are proposed: Ser. Calycinae Nielsen, ser. Ptenopae Nielsen, ser. Bellae Nielsen, Archidendron falcatum Nielsen, A. cockburnii Nielsen, A. sabahense Nielsen, A. fagifolium (Bl. ex Miq.) Nielsen var. borneense Nielsen, A. kunsrteri (Prain) Nielsen subsp. ashtonii Nielsen, A. ellipticum (Bl.) Nielsen subsp. cordifoliolatum Nielsen. New combinations are proposed in the Malesian species formerly referred to Abarema, Zygia and Morolobium by Kostermans. Keys to and an enumeration of the species are presented. 相似文献
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Feeding behavior of the brittle star Ophiura ophiura includesorienting posture, orienting movements, arm walking,changing the direction of walking arm coilingand ingestion. All sequential behavior patterns were releasedor enhanced by single low-molecular-weight compounds. Stimuliwhich released walking behavior at high concentrations(104 M) in all the test animals are listed in decreasingorder of sensitivity: sarcosine, glycine, urea, L-valine, L-leucine,L-methionine, L-homocysteine, L-norvaline, L-norleucine, L-threonine,L-serine, S-methyl-L-cysteine, L-proline. Threshold values forsingle amino acids were as much as 100 times different in differentindividuals and ranged from 3 x 109 to 3 x 107M for the most effective stimulus, sarcosine, and from 106to 104 M for proline. Above 105 M, only L-prolineregularly released a second behavior pattern, the arm coilingresponse, which temporarily inhibited the walkingbehavior. Behavioral thresholds for the walkingbehavior for L(+)-lactate and L-alanine were higher than thosefor the orienting movements. Thyoglycolic acid and ß-alaninereleased tube feet walking, which is not part of the feedingbehavior. Structureactivity comparisons were studied at estimated105 M concentrations. Gycline, sarcosine, L-valine, L-norvaline,L-leucine, L-isoleucine, DL-norleucine and DL-homocysteine releasedarm walking behavior in more than 75% of all thetests. With the exceptions of S-methyl-and S-ethyl-cysteine,and glycine methylester, derivatives of amino acids were noteffective behavioral stimuli in Ophiura ophiura. L-Isomers ofvaline and leucine regularly stimulated the walkingbehavior while their D-isomers were effective in some testsand ineffective in others. Acetylcholine iodide, acetyl-ß-methylcholine chloride and choline phosphate chloride regularly releasedwalking behavior at concentrations above 105M. 相似文献
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Magatte Ndiaye Roger Tine Babacar Faye Jean L. Ndiaye Ibrahima Diouf Aminata C. Lo Khadime Sylla Yemou Dieng Rachel Hallett Michael Alifrangis Oumar Gaye 《Comptes rendus biologies》2013,336(5-6):295-300
Senegal has since 2003 used sulphadoxine-pyrimethamine (SP) for Intermittent Preventive Treatment (IPT) of malaria in risk groups. However, the large-scale IPT strategy may result in increasing drug resistance. Our study investigated the possible impact of SP-IPT given to infants and children on the prevalence of SP-resistant haplotypes in the Plasmodium falciparum genes Pfdhfr and Pfdhps, comparing sites with and without IPTi/c. P. falciparum positives samples (n = 352) were collected from children under 5 years of age during two cross-sectional surveys in 2010 and 2011 in three health districts (two on IPTi/c and one without IPTi/c intervention) located in the southern part of Senegal. The prevalence of SP-resistance-related haplotypes in Pfdhfr and Pfdhps was determined by nested PCR followed by sequence-specific oligonucleotide probe (SSOP)–ELISA. The prevalence of the Pfdhfr double mutant haplotypes (CNRN and CICN) was stable between years at < 10% in the control group (P = 0.69), while it rose significantly in the IPTi/c group from 2% in 2010 to 20% in 2011 (P = 0.008). The prevalence of the Pfdhfr triple mutant haplotype (CIRN) increased in both groups, but only significantly in the IPTi/c group from 41% to 65% in 2011 (P = 0.005). Conversely, the Pfdhps 437G mutation decreased in both groups from 44.6% to 28.6% (P = 0.07) and from 66.7% to 47.5% (P = 0.02) between 2010 and 2011 in the control and the IPTi/c groups, respectively. Combined with Pfdhfr, there was a weak trend for decreasing prevalence of quadruple mutants (triple Pfdhfr + Pfdhps 437G) in both groups (P = 0.15 and P = 0.34). During the two cross-sectional surveys, some significant changes were observed in the SP-resistance-related genes. However, since these changes were observed in the two groups, the IPTi/c strategy does only seem to have limited impact on resistance development and other factors as well. However, continuous monitoring will be needed, due to the up-scaling of the IPTi/c strategy in Senegal according to WHO recommendations. 相似文献
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Background
Poor self-rated health (SRH) has been connected to immunological changes, and pregnancy complications have been suggested in the etiology of autoimmune diseases including inflammatory bowel disease (IBD). We evaluated the impact of self-rated pre-pregnancy health and pregnancy course, hyperemesis, gestational hypertension, and preeclampsia on risk of IBD.Methods
Information was collected by questionnaires from The Danish National Birth Cohort (enrolment 1996–2002) at 16th and 30th week of pregnancy and 6 months postpartum. A total of 55,699 women were followed from childbirth until development of IBD (using validated National Hospital Discharge Register diagnoses), emigration, death, or end of follow-up, 31st of October, 2011. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated using Cox proportional hazards models adjusting for age and evaluating pre-pregnancy BMI, parity, alcohol and tobacco consumption, and socio-occupational status as potential confounders.Results
Risk of IBD increased with decreasing level of self-rated pre-pregnancy health (p = 0.002) and was elevated in women with poor self-rated pregnancy course (HR, 1.61, 95% CI 1.22–2.12). Associations persisted for more than 5 years postpartum. Hyperemesis and preeclampsia were not significantly associated with risk of IBD.Conclusions
This is the first prospective observational study to suggest that poor self-rated health – in general and in relation to pregnancy – is associated with increased risk of IBD even in the long term though results needs further confirmation. Symptoms of specific pregnancy complications were, on the other hand, not significantly associated with risk of IBD. 相似文献7.
Multiple Locus Variable number of tandem repeat Analysis: A molecular genotyping tool for Paenibacillus larvae 下载免费PDF全文
Tine Descamps Lina De Smet Pieter Stragier Paul De Vos Dirk C. de Graaf 《Microbial biotechnology》2016,9(6):772-781
American Foulbrood, caused by Paenibacillus larvae, is the most severe bacterial disease of honey bees (Apis mellifera). To perform genotyping of P. larvae in an epidemiological context, there is a need of a fast and cheap method with a high resolution. Here, we propose Multiple Locus Variable number of tandem repeat Analysis (MLVA). MLVA has been used for typing a collection of 209 P. larvae strains from which 23 different MLVA types could be identified. Moreover, the developed methodology not only permits the identification of the four Enterobacterial Repetitive Intergenic Consensus (ERIC) genotypes, but allows also a discriminatory subdivision of the most dominant ERIC type I and ERIC type II genotypes. A biogeographical study has been conducted showing a significant correlation between MLVA genotype and the geographical region where it was isolated. 相似文献
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In living systems proteins are typically found in crowded environments where their effective interactions strongly depend on the surrounding medium. Yet, their association and dissociation needs to be robustly controlled in order to enable biological function. Uncontrolled protein aggregation often causes disease. For instance, cataract is caused by the clustering of lens proteins, i.e., crystallins, resulting in enhanced light scattering and impaired vision or blindness. To investigate the molecular origins of cataract formation and to design efficient treatments, a better understanding of crystallin association in macromolecular crowded environment is needed. Here we present a theoretical study of simple coarse grained colloidal models to characterize the general features of how the association equilibrium of proteins depends on the magnitude of intermolecular attraction. By comparing the analytic results to the available experimental data on the osmotic pressure in crystallin solutions, we identify the effective parameters regimes applicable to crystallins. Moreover, the combination of two models allows us to predict that the number of binding sites on crystallin is small, i.e. one to three per protein, which is different from previous estimates. We further observe that the crowding factor is sensitive to the size asymmetry between the reactants and crowding agents, the shape of the protein clusters, and to small variations of intermolecular attraction. Our work may provide general guidelines on how to steer the protein interactions in order to control their association. 相似文献
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Andersen Julie Høgsgaard Tjørnhøj-Thomsen Tine Reventlow Susanne Davidsen Annette Sofie 《Culture, medicine and psychiatry》2019,43(3):425-441
Culture, Medicine, and Psychiatry - An increasing number of young adults in Denmark experience difficulties in completing their education and holding down a job. Many of these young adults have... 相似文献