Number of adult female mites Varroa jacobsoni Oud. on hive debris from honey bee colonies artificially infested to monitor mite population increase (Mesostigmata: Varroidae)

Six honey bee colonies hived in Langstroth nuclei were each artificially infested with 100 phoretic Varroa mites. Hive debris on bottom inserts was inspected every 3–4 days. The adult Varroa mites were compared with mounted specimens and catalogued into lightly pigmented and darkly pigmented females. After 4 months, an acaricide treatment was used to estimate the final mite population. Based on light and dark adult counts, we propose a balancing equation that follows the Varroa population increase at 7 day intervals and allows the calculation of experimental population growth rates. The calculated Varroa finite rate of increase is =1.021. Exponential and logistic growth models fitted to the balancing equation data gave R ²=0.986 and R ²=0.991, respectively. To develop a more precise model it would be necessary to follow the population growth beyond our experimental data.     

Hive debris counts in honeybee colonies: a method to estimate the size of small populations and rate of growth of the miteVarroa jacobsoni Oud. (Mesostigmata: Varroidae)

Fifteen honeybee colonies (Apis mellifera L.) infested with the ectoparasiteVarroa jacobsoni Oud. were monitored for the number of mites falling to the bottom of the hive. Mites in the debris were counted periodically on the plastic sheet on which they were collected. Two months later, colonies were treated with an acaricide to determine mite population. A high positive correlation was found between the number of mites collected in the hive debris over different periods and the final population size. Based on this correlation, it was possible to use hive debris counts to predict the degree of infestation. Furthermore, counting fallen mites over a period of two months, followed by an acaricide treatment, might be a useful method of estimating the rate of growth ofV. jacobsoni in honeybee colonies.     

吐鲁番市胃食管反流病发生相关危险因素分析（附280例报道）

目的：探讨280例胃食管反流病（GERD）的分布特点及危险因素。方法：对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果：不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者（z=-2．939,P=0．003,）;汉族和维族患者占反流性食管炎和Barrett食管比例分别为42．4％、81_3％及56．5％、18．8％,其中汉族患者Barrett食管比例较高（X2=14．358,P=0．000）;肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高（P〈0．001）。结论：GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。     

Ozone in Spain's national parks and protected forests

In general, it is difficult to measure air pollutant concentrations in remote areas, as they are mostly national parks and protected areas. Passive samplers provide an accurate and inexpensive method for measuring cumulative exposures of different air pollutants. They have been used to collect ozone data in both laboratory and field at different geographical scales. The objective of the present study is to fill the knowledge gap regarding air quality in remote areas of Spain, such as national parks and protected areas. Because there were no systematic data sets on the main air pollutants that could affect these areas, an air quality measurement network was established between 2001 and 2004 on 19 locations inside Spanish national parks and protected areas. The data collected suggest that ozone levels in mountainous areas are high enough to affect sensitive vegetation. Most of the locations registered moderate-to-high ozone levels, with important interannual variability. Altitudinal ozone gradients were observed in most of the parks with complex topography due to the establishment of local circulations that incorporate polluted air masses from polluted airsheds or even long-range transport (i.e., Canary Islands). Different latitude-dependent, yearly cycles were also observed, showing two, one, or no clear peaks depending on the region. These findings extend to the most southerly locations, except in the Canary Islands, where pollution transported from other regions in the upper transport layers probably led to the high concentrations observed.     

Successful immunotherapy with matrix metalloproteinase-derived peptides in adjuvant arthritis depends on the timing of peptide administration

We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies.     

Characterization of terminal NeuNAcalpha2-3Galbeta1-4GlcNAc sequence in lipooligosaccharides of Neisseria meningitidis

Group B and C Neisseria meningitidis are the major cause of meningococcal disease in the United States and in Europe. N . meningitidis lipooligosaccharide (LOS), a major surface antigen, can be divided into 12 immunotypes of which L1 through L8 were found among Group B and C organisms. Groups B and C but not Group A may sialylate their LOSs with N-acetylneuraminic acid (NeuNAc) at the nonreducing end because they synthesize CMP-NeuNAc. Using sialic acid-galactose binding lectins as probes in an ELISA format, six of the eight LOS immunotypes (L2, L3, L4, L5, L7, and L8) in Groups B and C bound specifically to Maackia amurensis leukoagglutinin (MAL), which recognizes NeuNAcalpha2- 3Galbeta1-4GlcNAc/Glc sequence, but not to Sambucus nigra agglutinin, which binds NeuNAcalpha2-6Gal sequence. The combination of SDS-PAGE and MAL-blot analyses revealed that these six LOSs contained only the NeuNAcalpha2-3Galbeta1-4GlcNAc trisaccharide sequence in their 4.1 kDa LOS components, which have a common terminal lacto-N-neotetraose (LNnT, Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) structure when nonsialylated as shown by previous studies. The LOS-lectin binding was abolished when the LOSs were treated with Newcastle disease viral neuraminidase which cleaves alpha2-->3 linked sialic acid. Methylation analysis of a representative LOS (L2) confirmed that NeuNAc is 2-->3 linked to Gal. Thus, these LOSs structurally mimic certain glycolipids, i.e., paragloboside (LNnT-ceramide) and sialylparagloboside and some glycoproteins in having LNnT and N-acetyllactosamine sequences, respectively, with or without alpha2-->3 linked NeuNAc. The molecular mimicry of the LOSs may play a role in the pathogenesis of N.meningitidis by assisting the organism to evade host immune defenses in man.      

Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

Genetic diversity, structure, gene flow and evolutionary relationships within the Sorghum bicolor wild�Cweedy�Ccrop complex in a western African region

Gene flow between domesticated plants and their wild relatives is one of the major evolutionary processes acting to shape their structure of genetic diversity. Earlier literature, in the 1970s, reported on the interfertility and the sympatry of wild, weedy and cultivated sorghum belonging to the species Sorghum bicolor in most regions of sub-Saharan Africa. However, only a few recent surveys have addressed the geographical and ecological distribution of sorghum wild relatives and their genetic structure. These features are poorly documented, especially in western Africa, a centre of diversity for this crop. We report here on an exhaustive in situ collection of wild, weedy and cultivated sorghum assembled in Mali and in Guinea. The extent and pattern of genetic diversity were assessed with 15 SSRs within the cultivated pool (455 accessions), the wild pool (91 wild and weedy forms) and between them. F (ST) and R (ST) statistics, distance-based trees, Bayesian clustering methods, as well as isolation by distance models, were used to infer evolutionary relationships within the wild-weedy-crop complex. Firstly, our analyses highlighted a strong racial structure of genetic diversity within cultivated sorghum (F (ST) = 0.40). Secondly, clustering analyses highlighted the introgressed nature of most of the wild and weedy sorghum and grouped them into two eco-geographical groups. Such closeness between wild and crop sorghum could be the result of both sorghum's domestication history and preferential post-domestication crop-to-wild gene flow enhanced by farmers' practices. Finally, isolation by distance analyses showed strong spatial genetic structure within each pool, due to spatially limited dispersal, and suggested consequent gene flow between the wild and the crop pools, also supported by R (ST) analyses. Our findings thus revealed important features for the collection, conservation and biosafety of domesticated and wild sorghum in their centre of diversity.