9,004 research outputs found
Colección: Perfil #3
No full textThis board-book version of LM turns out to be quite creative. Ratoncete comes from school every afternoon and goes through the forest looking for adventures. He apparently blasts a horn into the ear of the sleeping lion. Don Leon wants to spank him as a result, but Ratoncete offers an apology, not an offer of help. Later, he happens upon the lion in his trap of ropes. 8 pages, counting both covers. 6½" x 9".Language note: SpanishNo Autho
Favissae. Feasting Pits in LM III
No full textThe practice of feasting - arguably one of the most important factors for social cohesion in the history of the island of Crete - can be followed from Early Minoan times onwards into the postpalatial phase. Here it is suggested that during the Final palatial period (LM II-IIIA1), feasting was used as a political instrument, and as such attested at Knossos and a few other primary centres. With the disappearance of the Knossos palace, the practice was progressively re-introduced in a series of minor settlements to reinforce local and regional cohesion. We illustrate this with Quartier Nu at Malia dating to the mature Late Minoan IIIA phase. Here a large architectural complex with an elaborate court (including one of the earliest pebble mosaics), seems at least partly to have been used for communal activities. Around the building several pits were found containing a material which suggests that some of it derived from feasting activities that took place in the immediate surroundings. The nature and importance of this material is discussed and compared with other possible cases identified elsewhere on the island. We discuss examples such as the North Rubbish Area at Kastelli Khania, interpreted by the excavators as the debris of activities originally taking place in a not yet uncovered LM IIIB1 sanctuary, or the particular assemblages found in pits and wells at Palaikastro during the LM III period as well as the presence of so-called LM III rubbish pits near other architectural structures, such as on the Kakavella hill at Khamalevri
Hot-spot consensus of fluoroquinolone-mediated DNA cleavage by gram-negative and gram-positive type II DNA topoisomerases
No full textBacterial DNA gyrase and topoisomerase IV are selective targets of fluoroquinolones. Topoisomerase IV versus gyrase and Gram-positive versus Gram-negative behavior was studied based on the different recognition of DNA sequences by topoisomerase– quinolone complexes. A careful statistical
analysis of preferred bases was performed on a large number (>400) of cleavage sites. We found discrete preferred sequences that were similar when using different enzymes (i.e. gyrase and topoisomerase IV) from the same bacterial source, but in part diverse when employing enzymes from
different origins (i.e. Escherichia coli and Streptococcus
pneumoniae). Subsequent analysis on the wild-type and mutated consensus sequences showed that: (i) Gn/Cn-rich sequences at and around the cleavage site are hot spots for quinolone-mediated strand breaks, especially for E. coli
topoisomerases: we elucidated positions required for quinolone and enzyme recognition; (ii) for S. pneumoniae enzymes only, A and T at positions �2 and +6 are discriminating cleavage determinants;(iii) symmetry of the target sequence is a key trait to promote cleavage and (iv) the consensus sequence adopts a heteronomous A/B conformation, which may trigger DNA processing by the enzyme–drug complex
The Difficult Case of Crystallization and Structure Solution for the ParC55 Breakage-Reunion Domain of Topoisomerase IV from Streptococcus pneumoniae.
No full textBACKGROUND: Streptococcus pneumoniae is the major cause of community-acquired pneumonia and is also associated with bronchitis, meningitis, otitis and sinusitis. The emergence and increasing prevalence of resistance to penicillin and other antibiotics has led to interest in other anti-pneumonococcal drugs such as quinolones that target the enzymes DNA gyrase and topoisomerase IV. During crystallization and in the avenues to finding a method to determine phases for the structure of the ParC55 breakage-reunion domain of topoisomerase IV from Streptococcus pneumoniae, obstacles were faced at each stage of the process. These problems included: majority of the crystals being twinned, either non-diffracting or exhibiting a high mosaic spread. The crystals, which were grown under conditions that favoured diffraction, were difficult to flash-freeze without loosing diffraction. The initial structure solution by molecular replacement failed and the approach proved to be unviable due to the complexity of the problem. In the end the successful structure solution required an in-depth data analysis and a very detailed molecular replacement search.
METHODOLOGY/PRINCIPAL FINDINGS: Crystal anti-twinning agents have been tested and two different methods of flash freezing have been compared. The fragility of the crystals did not allow the usual method of transferring the crystals into the heavy atom solution. Consequently, it was necessary to co-crystallize in the presence of the heavy atom compound. The multiple isomorphous replacement approach was unsuccessful because the 7 cysteine mutants which were engineered could not be successfully derivatized. Ultimately, molecular replacement was used to solve the structure by sorting through a large number of solutions in space group P1 using CNS.
CONCLUSIONS/SIGNIFICANCE: The main objective of this paper is to describe the obstacles which were faced and overcome in order to acquire data sets on such difficult crystals and determine phases for successful structure solution
Markets Equilibrium: The Is-Lm Model
No full text. The purpose of this study is to analyze how the concept of markets equilibrium: the IS-LM Model. This research uses library research method by using reference sources from books and journals according to the theme. The author uses a qualitative method which is explained graphically, namely the market balance of the IS-LM model where the focus is on money and goods markets associated with macroeconomics where researchers take the side of investors. The results of this study are that the balance in the economy is the point where the IS and LM curves intersect. This point provides an interest rate (r) and income level (Y) that satisfies the equilibrium conditions that occur in the goods market and money market. In other words, planned spending equals actual spending, and the demand for real money balances equals the supply. So that the IS-LM balance, it is stated that IS=LM
Clerocidin interacts with the cleavage complex of Streptococcus pneumoniae topoisomerase IV to induce selective irreversible DNA damage
No full textClerocidin (CL), a diterpenoid natural product, alkylates
DNA through its epoxide moiety and exhibits both anticancer and antibacterial activities. We have examined CLaction in the presence of topoisomerase IV from Streptococcus pneumoniae. CL promoted irreversible enzyme-mediated DNA cleavage leading to single- and double-stranded DNA breaks at specific sites. Reaction required the diterpenoid function: no cleavage was seen using a naphthalene-substituted analogue. Moreover, drug-induced DNA breakage was not observed using a mutant topoisomerase IV (ParC
Y118F) unable to form a cleavage complex with DNA.
Sequenceanalysis of 102 single-stranded DNA breaks
and 79 double-stranded breaks revealed an overwhelming
preference for G at the �1 position, i.e. immediately 50 of the enzyme DNA scission site. This specificity contrasts with that of topoisomerase IV cleavage with antibacterial quinolones. Indeed, CL stimulated DNA breakage by a quinolone-resistant topoisomerase IV (ParC S79F). Overall, the results indicate that topoisomerase IV facilitates selective irreversible CL attack at guanine and that its cleavage complex differs markedly from that of mammalian
topoisomerase II which promotes both irreversible
and reversible CL attack at guanine and cytosine,
respectively. The unique ability to form exclusively
irreversible DNA breaks suggests topoisomerase IV
may be a key intracellular target of CL in bacteria
Abundance of intrinsic disorder in SV-IV, a multifunctional androgen-dependent protein secreted from rat seminal vesicle
No full textThe potent immunomodulatory, anti-inflammatory and procoagulant properties of the
protein no. 4 secreted from the rat seminal vesicle epithelium (SV-IV) have been
previously found to be modulated by a supramolecular monomer-trimer equilibrium.
More structural details that integrate experimental data into a predictive framework
have recently been reported. Unfortunately, homology modelling and fold-recognition
strategies were not successful in creating a theoretical model of the structural
organization of SV-IV. It was inferred that the global structure of SV-IV is not similar
to any protein of known three-dimensional structure. Reversing the classical approach
to the sequence-structure-function paradigm, in this paper we report on novel
information obtained by comparing physicochemical parameters of SV-IV with two
datasets made of intrinsically unfolded and ideally globular proteins. In addition, we
have analysed the SV-IV sequence by several publicly available disorder-oriented
predictors. Overall, disorder predictions and a re-examination of existing experimental
data strongly suggest that SV-IV needs large plasticity to efficiently interact with the
different targets that characterize its multifaceted biological function and should be
therefore better classified as an intrinsically disordered protein
Presence of collagen IV in the ciliary zonules of the human eye: An immunohistochemical study by LM and TEM
No full textThe ciliary zonules of the eye are composed of fibrillar and non-fibrillar components. Fibrils provide tensile strength and elasticity, whereas non-fibrillar components serve as a coating surrounding the fibrils. This coating behaves as a barrier to macromolecules. The present light and transmission electron microscopic (LM and TEM) study identified collagen IV as a novel component of this coating. Collagen IV was demonstrated by pre-embedding and postembedding immunohistochemical (IHC) techniques using monoclonal and polyclonal antibodies. The specificity of the polyclonal anticollagen IV antibody was verified by ELISA
<Articles>A Dynamical IS-LM Model
No full text[抄録]IS-LM モデルは、ヒックスによるケインズ経済学の因果関係を重視しながら要約したモデルと解釈することができる。IS-LM モデルの安定性分析はすでに研究成果があるが、1S-LM モデルの動学化はほとんど研究成果がない。本稿は IS-LM モデルの動学化を試みる。まず投資関数に資本ストックを取り入れ、資本蓄積と経済の変動を考える。次にカルドアモデルを考慮し、投資の予想収益率表の変化を仮定し、経済に循環が発生することを考察する。
[Abstract]In this paper, The author tries to build a Dynamical IS-LM Model. The lnvestment depends on two factors, one is the rate of interest, and the other is the rate of prosperity yield of the investment. I will focus on the second factor. As was shown by Kaldor, the rate of prosperity yield has nonlinear fluctuations. By means of this character, This study proposes an IS-LM model that generates a cycle.departmental bulletin pape
In vivo vaccination with <i>Lm-EGFRvIII</i> results in antigen specific T cell responses.
No full textC57BL/6 mice were treated with Lm-EGFRvIII x1 and Lm-EGFRvIII x5 and seven days later splenocytes were tested for their response to i) DMSO vehicle, or ii) SIINFEKL peptide by intracellular cytokine staining. iii) Percent of CD3+CD8+ T cells and iv) absolute number of SIINFEKL-specific splenocytes. Each symbol represents one animal. NS = not significant. (Student’s T-test).</p
- …
