149,873 research outputs found
Characterization of Novel OmpA-Like Protein of Leptospira interrogans That Binds Extracellular Matrix Molecules and Plasminogen
Leptospira interrogans is the etiological agent of leptospirosis, a zoonotic disease of human and veterinary concern. The identification of novel proteins that mediate host-pathogen interactions is important for understanding the bacterial pathogenesis as well as to identify protective antigens that would help fight the disease. We describe in this work the cloning, expression, purification and characterization of three predicted leptospiral membrane proteins, LIC10258, LIC12880 (Lp30) and LIC12238. We have employed Escherichia coli BL21 (SI) strain as a host expression system. Recently, we have identified LIC12238 as a plasminogen (PLG)-binding receptor. We show now that Lp30 and rLIC10258 are also PLG-receptors of Leptospira, both exhibiting dose-dependent and saturating binding (KD, 68.8±25.2 nM and 167.39±60.1 nM, for rLIC10258 and rLIC12880, respectively). In addition, LIC10258, which is a novel OmpA-like protein, binds laminin and plasma fibronectin ECM molecules and hence, it was named Lsa66 (Leptospiral surface adhesin of 66 kDa). Binding of Lsa66 to ECM components was determined to be specific, dose-dependent and saturable, with a KD of 55.4±15.9 nM to laminin and of 290.8±11.8 nM to plasma fibronectin. Binding of the recombinant proteins to PLG or ECM components was assessed by using antibodies against each of the recombinant proteins obtained in mice and confirmed by monoclonal anti-polyhistidine antibodies. Lsa66 caused partial inhibition on leptospiral adherence to immobilized ECM and PLG. Moreover, this adhesin and rLIC12238 are recognized by antibodies in serum samples of confirmed leptospirosis cases. Thus, Lsa66 is a novel OmpA-like protein with dual activity that may promote the attachment of Leptospira to host tissues and may contribute to the leptospiral invasion. To our knowledge, this is the first leptospiral protein with ECM and PLG binding properties reported to date
Chronic obstructive pulmonary diseases: Recent trends
Chronic obstructive pulmonary disease (COPD) which includes
chronic bronchitis and emphysema is a major cause of morbid
i t y a n d m o r t a l i t y i n industrialised countries. An increasing
prevalence of the disease has been observed in our country
as well. Chronic bronchitis, emphysema and bronchial asthma
are the major causes of obstruction to airflow from the lungs.
Unlike Bronchial asthma, t h e a i r f l o w l i m i t a t i o n i n C O P D i s
persistent. A CIBA symposium in 1959 defined chronic bronchitis,
as a c o n d i t i o n o f s u b j e c t s w i t h chronic or recurrent
excessive mucous secretions i n t h e b r o n c h i a l s i t e w i t h o u t a
demonstrable cause, either local or general occurring most on
most of the days for at least three months in the, year during
last two years. National Heart lung a n d B l o o d I n s t i t u t e i n
Intermittent positive pressure Breathing trial defined emphysema
morphologically as a condition of the lung characterised by
abnormal permanent enlargement of t h e a i r s p a c e s d i s t a l
t o the terminal bronchioles a c c o m p a n i e d b y d e s t r u c t i v e
changes of the alveolar walls and without obvious fibrosis
A Cultural Tourism Strategy: Enriching Culture and Building Tourism in Buffalo Niagara
Their continued dedication to the region\u27s cultural, arts and heritage organizations and the development of cultural tourism has been, and will continue to be, essential to attaining the vision of “A Cultural Tourism Strategy”. The cultural tourism mission is to strengthen cultural, artistic and heritage organizations; expand individual opportunities for creativity and interpretation; help our regional economy grow; enhance the quality of life in our communities; advance the image and identity of the region; and build the region\u27s reputation as a world-class tourism destination. These benefits reinforce one another and can be achieved together
After-School Toolkit: Tips, Techniques and Templates for Improving Program Quality
This toolkit offers program managers a practical, hands-on guide for implementing quality programming in the after-school hours. The kit includes the tools and techniques that increased the quality of literacy programming and helped improve student reading gains in the Communities Organizing Resources to Advance Learning (CORAL) initiative of The James Irvine Foundation. CORAL is an eight-year, $58 million after-school initiative aimed at improving education achievement in low-performing schools in five California cities. In addition to strategies, process and instructions, this toolkit offers a series of tools program staff can use to build the quality of their after-school program
Spectroscopic characterization of the oxo-transfer reaction from a bis(µ-oxo)dicopper(III) complex to triphenylphosphine
The oxygen-atom transfer reaction from the bis(µ-oxo)dicopper(III) complex [CuIII2(µ-O)2(L)2]2+1, where L =N,N,N,N -tetraethylethylenediamine, to PPh3 has been studied by UV-vis, EPR, 1H NMR and Cu K-edge X-ray absorption spectroscopy in parallel at low temperatures (193 K) and above. Under aerobic conditions (excess dioxygen), 1 reacted with PPh3, giving OPPh3 and a diamagnetic species that has been assigned to an oxo-bridged dicopper(II) complex on the basis of EPR and Cu K-edge X-ray absorption spectroscopic data. Isotope-labeling experiments (18O2) established that the oxygen atom incorporated into the triphenylphosphine oxide came from both complex 1 and exogenous dioxygen. Detailed kinetic studies revealed that the process is a third-order reaction; the rate law is first order in both complex 1 and triphenylphosphine, as well as in dioxygen. At temperatures above 233 K, reaction of 1 with PPh3 was accompanied by ligand degradation, leading to oxidative N-dealkylation of one of the ethyl groups. By contrast, when the reaction was performed in the absence of excess dioxygen, negligible substrate (PPh3) oxidation was observed. Instead, highly symmetrical copper complexes with a characteristic isotropic EPR signal at g= 2.11 were formed. These results are discussed in terms of parallel reaction channels that are activated under various conditions of temperature and dioxygen
LORAN-C, an overview
LORAN-C a highly accurate radio navigation positioning system which operates at an assigned frequency of 10 kHz, and provides phase-coded pulses to develop hyperbolic time-difference lines-of-position (LOP's) was evaluated. LORAN-C provides precise time and time interval to within plus or minus 5 microseconds of UTC. The steps taken to plan, install, operate, and maintain the LORAN-C system up to the year 2000 are discussed. Topics included in the discussion were: theory of operation, timing, chain lanning, group repetition interval, coding delay versus emission delay, chain calibration, chart verification, system accuracy, signal reliability, and future developments
The relationship between Cognitive Reserve and Math Abilities
Cognitive Reserve is the capital of knowledge and experiences that an individual acquires over their life-span. Cognitive Reserve is strictly related to Brain Reserve, which is the ability of the brain to cope with damage. These two concepts could explain many phenomena such as the modality of onset in dementia or the different degree of impairment in cognitive abilities in aging. The aim of this study is to verify the effect of Cognitive Reserve, as measured by a questionnaire, on a variety of numerical abilities (number comprehension, reading and writing numbers, rules and principles, mental calculations and written calculations), in a group of healthy older people (aged 65-98 years). Sixty older individuals were interviewed with the Cognitive Reserve Index questionnaire (CRIq), and assessed with the Numerical Activities of Daily Living battery (NADL), which included formal tasks on math abilities, an informal test on math, one interview with the participant, and one interview with a relative on the perceived math abilities. We also took into account the years of education, as another proxy for Cognitive Reserve. In the multiple regression analyses on all formal tests, CRIq scores did not significantly predict math performance. Other variables, i.e., years of education and Mini-Mental State Examination score, accounted better for math performance on NADL. Only a subsection of CRIq, CRIq-Working-activity, was found to predict performance on a NADL subtest assessing informal use of math in daily life. These results show that education might better explain abstract math functions in late life than other aspects related to Cognitive Reserve, such as lifestyle or occupational attainment
A survey of the coverage, use and application of ancient woodland indicator lists in the UK
This report presents the results of a survey into the current use of ancient woodland indicator species lists in the UK. The idea of using species particularly vascular plants as indicators of ancient woodlands can be dated back to the 1970s and the work of Peterken. Since then a wide number of lists of Ancient Woodland Indicators (AWIs)have been produced, some based on expert opinions, some utilising field surveys, others adapted from existing lists. Recently developed lists, e.g. the lists for Scotland, Wales and Northern Ireland have been based on either robust reviews of existing lists, and/or expert opinion and/or field surveys and statistical analysis. Concerns however have been expressed regarding the use of lists and these concerns appear to be supported by the uncritical use of indicator species in recent planning inquiries, e.g. not recognising that indicators are indicators and considering them to be the key value of a woodland. A survey was undertaken of relevant individuals working in biological record centres, local authorities and key agencies across the UK. The survey sought to identify what lists of Ancient Woodland Indicators are currently in use, where possible to determine the methods used in developing these lists. The survey also sought to assess the awareness of ancient woodland indicator lists and review the ways in which these were used. A total of 419 questionnaires were sent out; a response rate of 11% was obtained. Follow up phone conversations were held with key individuals involved in developing ancient woodland indicator lists. Responses were received from all counties excluding: Buckinghamshire, Cheshire, Essex, Huntingdonshire, Middlesex, Northamptonshire, Staffordshire, Wiltshire and Worcestershire. In addition, the Lancashire respondent stated there was no AWI list for Lancashire. The key findings of the survey were: • There is a wide variety of lists of Ancient Woodland Indicators lists available covering most of the UK. • Most individuals using indicator lists are unaware of the methods used to produce the lists and therefore of their robustness. Some key stakeholders are unaware of the existence of indicator lists in their area. • Attitudes to ancient woodland indicator lists are variable, as is their use. • Few lists use species thresholds or weightings in determining whether a site is ancient, several lists are currently under review. • There are over 200 species listed on the various Ancient Woodland Indicators lists, few species are common to more than a quarter of the lists
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