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81.
82.
Lees, D. C., Rougerie, R., Zeller‐Lukashort, C. & Kristensen, N. P. (2010). DNA mini‐barcodes in taxonomic assignment: a morphologically unique new homoneurous moth clade from the Indian Himalayas described in Micropterix (Lepidoptera, Micropterigidae). —Zoologica Scripta, 39, 642–661. The first micropterigid moths recorded from the Himalayas, Micropterix cornuella sp. n. and Micropterix longicornuella sp. n. (collected, respectively, in 1935 in the Arunachel Pradesh Province and in 1874 in Darjeeling, both Northeastern India) constitute a new clade, which is unique within the family because of striking specializations of the female postabdomen: tergum VIII ventral plate forming a continuous sclerotized ring, segment IX bearing a pair of strongly sclerotized lateroventral plates, each with a prominent horn‐like posterior process. Fore wing vein R unforked, all Rs veins preapical; hind wing devoid of a discrete vein R. The combination of the two first‐mentioned vein characters suggests close affinity to the large Palearctic genus Micropterix (to some species of which the members of the new clade bear strong superficial resemblance). Whilst absence of the hind wing R is unknown in that genus, this specialization is not incompatible with the new clade being subordinate within it. A 136‐bp fragment of Cytochrome oxidase I successfully amplified from both of the 75‐year‐old specimens strongly supports this generic assignment. Translated to amino acids, this DNA fragment is highly diagnostic of this genus, being identical to that of most (16 of the 26) Micropterix species studied comparatively here, 1–4 codons different from nine other species (including Micropterix wockei that in phylogenetic analyses we infer to be sister to other examined species), whilst 7–15 codons different to other amphiesmenopteran genera examined here. A dating analysis also suggests that the large clade excluding M. wockei to which M. cornuella belongs appeared <31 million years ago. These findings encourage discovery of a significant radiation of Micropterix in the Himalayan region. Our analysis has more general implications for testing the assignment of DNA mini‐barcodes to a taxon, in cases such as museum specimens where the full DNA barcode cannot be recovered.  相似文献   
83.
Collagen is the main load bearing protein in many soft tissues, and in cardiovascular tissues in particular. In many tissues collagen has a specific architecture that is crucial for the biomechanical function of the tissue. Typical examples are the hammock-shaped collagen architecture in heart valves and a helical pattern in arteries. One of the objectives in cardiovascular tissue engineering is the reconstitution of this architecture. It is hypothesized that the architecture is mediated by mechanical stimulation. Computational models were developed to predict the mechanoregulation of the collagen architecture. This review recapitulates the key modeling assumptions and results achieved to date.  相似文献   
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Cereulide production has until now been restricted to the species Bacillus cereus. Here we report on two psychrotolerant Bacillus weihenstephanensis strains, MC67 and MC118, that produce cereulide. The strains are atypical with regard to pheno- and genotypic characteristics normally used for identification of emetic B. cereus strains. MC67 and MC118 produced cereulide at temperatures of as low as 8°C.  相似文献   
86.
Plant responses to mechanical stress (e.g. wind or touch) involve a suite of physiologic and developmental changes, collectively known as thigmomorphogenesis, including reductions in height increment, Young's modulus of stems, shoot growth, and seed production, and increased stem girth and root growth. A role of the phytohormone ethylene in thigmomorphogenesis has been proposed but the extent of this involvement is not entirely clear. To address this issue, wild-type (WT) and ethylene-insensitive transgenic (Tetr) tobacco ( Nicotianum tabacum ) plants were subjected to three levels of mechanical stress: 0, 25 and 75 daily flexures. Flexed plants produced shorter, thicker stems with a lower Young's modulus than non-flexed ones, and these responses occurred independently of genotype. This suggests that ethylene does not play a role in thigmomorphogenesis-related changes in stem characteristics in tobacco. The effect of mechanical stress on dry mass increment (growth), on the other hand, differed between the genotypes: in the WT plants, shoot growth but not root growth was reduced under mechanical stress, resulting in reduced total growth and increased root mass fractions. In the Tetr plants, neither shoot nor root growth were affected. This suggests that ethylene is involved in the inhibition of tobacco shoot growth under mechanical stress.  相似文献   
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The purpose of this study was to describe the microRNA (miRNA) expression profiles of neutrophils and their precursors from the initiation of granulopoiesis in the bone marrow to extravasation and accumulation in skin windows. We analyzed three different cell populations from human bone marrow, polymorphonuclear neutrophil (PMNs) from peripheral blood, and extravasated PMNs from skin windows using the Affymetrix 2.0 platform. Our data reveal 135 miRNAs differentially regulated during bone marrow granulopoiesis. The majority is differentially regulated between the myeloblast/promyelocyte (MB/PM) and myelocyte/metamyelocyte (MC/MM) stages of development. These 135 miRNAs were divided into six clusters according to the pattern of their expression. Several miRNAs demonstrate a pronounced increase or reduction at the transition between MB/PM and MC/MM, which is associated with cell cycle arrest and the initiation of terminal differentiation. Seven miRNAs are differentially up-regulated between peripheral blood PMNs and extravasated PMNs and only one of these (miR-132) is also differentially regulated during granulopoiesis. The study indicates that several different miRNAs participate in the regulation of normal granulopoiesis and that miRNAs might also regulate activities of extravasated neutrophils. The data present the miRNA profiles during the development and activation of the neutrophil granulocyte in healthy humans and thus serves as a reference for further research of normal and malignant granulocytic development.  相似文献   
89.
A major challenge for strategies to combat the human malaria parasite Plasmodium vivax is the presence of hypnozoites in the liver. These dormant forms can cause renewed clinical disease after reactivation through unknown mechanisms. The closely related non-human primate malaria P. cynomolgi is a frequently used model for studying hypnozoite-induced relapses. Here we report the generation of the first transgenic P. cynomolgi parasites that stably express fluorescent markers in liver stages by transfection with novel DNA-constructs containing a P. cynomolgi centromere. Analysis of fluorescent liver stages in culture identified, in addition to developing liver-schizonts, uninucleate persisting parasites that were atovaquone resistant but primaquine sensitive, features associated with hypnozoites. We demonstrate that these hypnozoite-forms could be isolated by fluorescence-activated cell sorting. The fluorescently-tagged parasites in combination with FACS-purification open new avenues for a wide range of studies for analysing hypnozoite biology and reactivation.  相似文献   
90.

Objectives

To investigate the associations of environmental MS risk factors with clinical and MRI measures of progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event.

Methods

We analyzed 211 CIS patients (age: 28.9±7.8 years) enrolled in the SET study, a multi-center study of high-risk CIS patients. Pre-treatment samples were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) early nuclear antigen-1 (EBNA-1), viral capsid antigen (VCA), early antigen-diffuse (EA-D), 25 hydroxy-vitamin D3 and cotinine levels and HLA DRB1*1501 status. The inclusion criteria required evaluation within 4 months of the initial demyelinating event, 2 or more brain MRI lesions and the presence of two or more oligoclonal bands in cerebrospinal fluid. All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months.

Results

The time to first relapse decreased and the number of relapses increased with anti-CMV IgG positivity. Smoking was associated with increased number and volume of contrast-enhancing lesions (CEL) during the 2-year period. The cumulative number of CEL and T2 lesions during the 2-year period was greater for individuals in the highest quartile of anti-EBV VCA IgG antibodies. The percent loss of brain volume was increased for those in the highest quartile of with anti-EBV VCA IgG antibodies.

Conclusions

Relapses in CIS patients were associated with CMV positivity whereas anti-EBV VCA positivity was associated with progression on MRI measures, including accumulation of CEL and T2 lesions and development of brain atrophy.  相似文献   
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