bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rethinking the OSCE as a Tool for National Competency Evaluation
Authors: Boyd M. A. , Gerrow J.D. , Duquette P. 
Published: April 2004

The relatively recent curriculum change to Problem‐Based Learning/Case‐Based Education has stimulated the development of new evaluation tools for student assessment. The Objective Structured Clinical Examination (OSCE) has become a popular method for such assessment.The National Dental Examining Board of Canada (NDEB) began using an OSCE format as part of the national certification testing process for licensure of beginning dentists in Canada in 1996. The OSCE has been well received by provincial licensing authorities, dental schools and students. ‘Hands on’ clinical competency is trusted to the dental programs and verified through NDEB participation in the Accreditation process.The desire to refine the OCSE has resulted in the development of a new format. Previously OSCE stations consisted of case‐based materials and related multiple‐choice questions. The new format has case‐based material with an extended match presentation. Candidates ‘select one or more correct answers’ from a group of up to15 options. The blueprint is referenced to the national competencies for beginning practitioners in Canada.This new format will be available to students on the NDEB website for information and study purposes. Question stems and options will remain constant. Case histories and case materials will change each year.This new OSCE will be easier to administer and be less expensive in terms of test development. Reliability and validity is enhanced by involving content experts from all faculties in test development, by having the OSCE verified by general practitioners and by making the format available to candidates. The new OSCE will be pilot tested in September 2004. Examples will be provided for information and discussion.
Establishment of an atopic dermatitis‐like skin model in a hairless mouse by repeated elicitation of contact hypersensitivity that enables to conduct functional analyses of the stratum corneum with various non‐invasive biophysical instruments
Authors: Matsumoto Katsuo , Mizukoshi Koji , Oyobikawa Midori , Ohshima Hiroshi , Tagami Hachiro 
Published: April 2004

Background/aims: Pathogenesis of atopic dermatitis (AD) has been studied in animal models such as the NC/Nga mouse strain or Balb/C mice that are repeatedly treated with 2,4,6‐trinitro‐1‐chrolobenzene (TNCB). These mice exhibit features of chronic contact dermatitis, including an intensified early type skin reaction, increased number of mast cells and elevated serum IgE levels with a shift of cutaneous cytokine expression from a type 1 to type 2 profile. However, it is difficult to investigate the unique skin changes of AD such as dry skin, barrier dysfunction, and increased turnover of the stratum corneum (SC) in these animals with biophysical instruments because of the presence of their fur coats. In this study, we succeeded in establishing a mouse model of AD in hairless mice that are suitable for various functional analyses of the SC as well as for examining the immunological characteristics of human AD by treating TNCB‐contact sensitized hairless mice with 1% TNCB every other day for 36 days.Methods: In hairless animals treated with TNCB every 2 days for 36 days, we measured time courses of skin swelling induced by contact hypersensitivity reaction on days 0, 6, 20 and 36. During the time course, non‐invasive measurements for skin surface condition with biophysical instruments were conducted, and the area size and the rear surface villi of corneocytes obtained were measured. Also skin samples and blood samples were taken at each time point for histology and measurement of serum IgE level.Results: A gradual intensification of an early type contact hypersensitivity reaction was observed over the treatment period. These mice exhibited reduced SC hydration, heightened trans‐epidermal water loss, and increased skin thickness. These mice also showed a decrease in the surface area size of each corneocytes and marked villus formation on their rear surface. Histologically, there was an increase in the number of CD4 and CD8 positive T cells in the epidermis. Also observed was a marked increase in the number of dermal mast cells and eosinophils, which correlated with elevated serum IgE levels induced by TNCB treatments.Conclusions: From the results obtained we conclude that repeated treatments of TNCB‐sensitized hairless mice with TNCB provides a useful means by which to study the pathological characteristics of AD skin lesions as well as their immunological characteristics.
Analysis of the absorbance spectra of skin lesions as a helpful tool for detection of major pathophysiological changes
Authors: Takiwaki Hirotsugu , Miyaoka Yuki , Arase Seiji 
Published: April 2004

Background/aims: Although reflectance spectrophotometry is often applied to measurement of skin color, raw data of reflectance spectra of normal and lesional skin are difficult to analyze. The purpose of this pilot study was to determine whether measurement of spectral difference in absorbance (SDA) between various skin lesions and normal skin adjacent to them could yield useful information for clinics in dermatology.Methods: We studied spectral reflectance of a total of 173 various skin lesions. After converting obtained reflectance into apparent absorbance A (=log10(1/reflectance)), we examined the profile of SDA, that is, Alesion−Anormal skin in the range of 400–700 nm, and compared them with the absorbance spectra of melanin and hemoglobin.Results: SDA of epidermal pigmentary disorders was similar to the absorption spectrum of melanin in vitro, but the cases with intradermal melanin deposition showed a different pattern, reflecting the scattering effect of the dermis. SDA of erythematous lesions was similar to the spectra of either oxygenated or reduced hemoglobin, and varied according to the oxygenated level of cutaneous blood. SDA of lesions with a combination of factors appeared as a simple summation of spectra corresponding to each of the factors.Conclusion: Our method may offer easy and quick detection of major pathophysiological changes in skin lesions.
Organization of
lin
Genes and IS
6100
among Different Strains of Hexachlorocyclohexane-Degrading
Sphingomonas paucimobilis
: Evidence for Horizontal Gene Transfer
Authors: Dogra Charu , Raina Vishakha , Pal Rinku , Suar Mrutyunjay , Lal Sukanya , Gartemann Karl-Heinz , Holliger Christof , van der Meer Jan Roelof , Lal Rup 
Published: April 2004

ABSTRACT

The organization of
lin
genes and IS
6100
was studied in three strains of
Sphingomonas paucimobilis
(B90A, Sp+, and UT26) which degraded hexachlorocyclohexane (HCH) isomers but which had been isolated at different geographical locations. DNA-DNA hybridization data revealed that most of the
lin
genes in these strains were associated with IS
6100
, an insertion sequence classified in the IS
6
family and initially found in
Mycobacterium fortuitum.
Eleven, six, and five copies of IS
6100
were detected in B90A, Sp+, and UT26, respectively. IS
6100
elements in B90A were sequenced from five, one, and one regions of the genomes of B90A, Sp+, and UT26, respectively, and were found to be identical. DNA-DNA hybridization and DNA sequencing of cosmid clones also revealed that
S. paucimobilis
B90A contains three and two copies of
linX
and
linA
, respectively, compared to only one copy of these genes in strains Sp+ and UT26. Although the copy number and the sequence of the remaining genes of the HCH degradative pathway (
linB
,
linC
,
linD
, and
linE
) were nearly the same in all strains, there were striking differences in the organization of the
linA
genes as a result of replacement of portions of DNA sequences by IS
6100
, which gave them a strange mosaic configuration. Spontaneous deletion of
linD
and
linE
from B90A and of
linA
from Sp+ occurred and was associated either with deletion of a copy of IS
6100
or changes in IS
6100
profiles. The evidence gathered in this study, coupled with the observation that the G+C contents of the
linA
genes are lower than that of the remaining DNA sequence of
S. paucimobilis
, strongly suggests that all these strains acquired the
linA
gene through horizontal gene transfer mediated by IS
6100
. The association of IS
6100
with the rest of the
lin
genes further suggests that IS
6100
played a role in shaping the current
lin
gene organization.
Transcriptional Organization and Posttranscriptional Regulation of the
Bacillus subtilis
Branched-Chain Amino Acid Biosynthesis Genes
Authors: Mäder Ulrike , Hennig Susanne , Hecker Michael , Homuth Georg 
Published: April 2004

ABSTRACT

In
Bacillus subtilis
, the genes of the branched-chain amino acids biosynthetic pathway are organized in three genetic loci: the
ilvBHC-leuABCD
(
ilv-leu
) operon,
ilvA
, and
ilvD
. These genes, as well as
ybgE
, encoding a branched-chain amino acid aminotransferase, were recently demonstrated to represent direct targets of the global transcriptional regulator CodY. In the present study, the transcriptional organization and posttranscriptional regulation of these genes were analyzed. Whereas
ybgE
and
ilvD
are transcribed monocistronically, the
ilvA
gene forms a bicistronic operon with the downstream located
ypmP
gene, encoding a protein of unknown function. The
ypmP
gene is also directly preceded by a promoter sharing the regulatory pattern of the
ilvA
promoter. The
ilv-leu
operon revealed complex posttranscriptional regulation: three mRNA species of 8.5, 5.8, and 1.2 kb were detected. Among them, the 8.5-kb full-length primary transcript exhibits the shortest half-life (1.2 min). Endoribonucleolytic cleavage of this transcript generates the 5.8-kb mRNA, which lacks the coding sequences of the first two genes of the operon and is predicted to carry a stem-loop structure at its 5′ end. This processing product has a significantly longer half-life (3 min) than the full-length precursor. The most stable transcript (half-life, 7.6 min) is the 1.2-kb mRNA generated by the processing event and exonucleolytic degradation of the large transcripts or partial transcriptional termination. This mRNA, which encompasses exclusively the
ilvC
coding sequence, is predicted to carry a further stable stem-loop structure at its 3′ end. The very different steady-state amounts of mRNA resulting from their different stabilities are also reflected at the protein level: proteome studies revealed that the cellular amount of IlvC protein is 10-fold greater than that of the other proteins encoded by the
ilv-leu
operon. Therefore, differential segmental stability resulting from mRNA processing ensures the fine-tuning of the expression of the individual genes of the operon.
The PmlI-PmlR Quorum-Sensing System in
Burkholderia pseudomallei
Plays a Key Role in Virulence and Modulates Production of the MprA Protease
Authors: Valade E. , Thibault F. M. , Gauthier Y. P. , Palencia M. , Popoff M. Y. , Vidal D. R. 
Published: April 2004

ABSTRACT

Burkholderia pseudomallei
is the causative agent of melioidosis, an often fatal infection of humans and animals. The virulence of this pathogen is thought to depend on a number of secreted proteins, including the MprA metalloprotease. We observed that MprA is produced upon entry into the stationary phase, when the cell density is high, and this prompted us to study cell density-dependent regulation in
B. pseudomallei
. A search of the
B. pseudomallei
genome led to identification of a quorum-sensing system involving the LuxI-LuxR homologs PmlI-PmlR. PmlI directed the synthesis of an
N
-acylhomoserine lactone identified as
N
-decanoylhomoserine lactone. A
B. pseudomallei pmlI
mutant was significantly less virulent than the parental strain in a murine model of infection by the intraperitoneal, subcutaneous, and intranasal routes. Inactivation of
pmlI
resulted in overproduction of MprA at the onset of the stationary phase. A wild-type phenotype was restored following complementation with
pmlI
or addition of cell-free culture supernatant. In contrast, there was no significant difference between the virulence of a
B. pseudomallei mprA
mutant and the virulence of the wild-type strain. These results suggest that the PmlI-PmlR quorum-sensing system of
B. pseudomallei
is essential for full virulence in a mouse model and downregulates the production of MprA at a high cell density.
Characterization of the
cis
-Acting Regulatory Element Controlling HrpB-Mediated Activation of the Type III Secretion System and Effector Genes in
Ralstonia solanacearum
Authors: Cunnac Sébastien , Boucher Christian , Genin Stéphane 
Published: April 2004

ABSTRACT

The ability of
Ralstonia solanacearum
to cause disease on plants depends on its type III secretion system (TTSS) encoded by
hrp
genes. The expression of
hrp
genes and known TTSS substrates is coordinately regulated by HrpB, a member of the AraC family of transcriptional regulators. Two HrpB-regulated promoters (
hrpY
and
popABC
) were characterized by deletion analysis, and the HrpB-dependent activation of these promoters was found to be conferred by a 25-nucleotide DNA element, the
hrp
II
box (TTCGn16TTCG), which is present in other
hrp
promoters. The
hrp
II
box element is an imperfect plant inducible promoter box, an element which was originally found in
hrp
promoters of
Xanthomonas campestris
(S. Fenselau and U. Bonas, Mol. Plant-Microbe Interact. 8:845-854, 1995) but which was not characterized at the molecular level. Site-directed mutagenesis showed that the
hrp
II
box is essential for
hrpY
promoter activation in vivo. Functional analysis of the
hrp
II
box element identified critical parameters that are required for HrpB-dependent activity. Further mapping analyses of several other
hrpB
-dependent promoters also indicated that the position of the
hrp
II
box is conserved, at −70 to −47 bp from the transcriptional start. As a first step toward identifying novel TTSS effectors, we used the
hrp
II
box consensus sequence to search for potential HrpB-regulated promoters in the complete genome sequence of
R. solanacearum
strain GMI1000. Among the 114 genes identified, a subset of promoters was found to have a structural relationship with
hrp
promoters, thus providing a pool of candidate genes encoding TTSS effectors.
Conserved Target for Group II Intron Insertion in Relaxase Genes of Conjugative Elements of Gram-Positive Bacteria
Authors: Staddon Jack H. , Bryan Edward M. , Manias Dawn A. , Dunny Gary M. 
Published: April 2004

ABSTRACTThe lactococcal group II intron Ll.ltrB interrupts theltrBrelaxase gene within a region that encodes a conserved functional domain. Nucleotides essential for the homing of Ll.ltrB into an intronless version ofltrBare found exclusively at positions required to encode amino acids broadly conserved in a family of relaxase proteins of gram-positive bacteria. Two of these relaxase genes,pcfGfrom the enterococcal plasmid pCF10 and the ORF4 gene in the streptococcal conjugative transposon Tn5252, were shown to support Ll.ltrB insertion into the conserved motif at precisely the site predicted by sequence homology withltrB. Insertion occurred through a mechanism indistinguishable from retrohoming. Splicing and retention of conjugative function was demonstrated for pCF10 derivatives containing intron insertions. Ll.ltrB targeting of a conserved motif of a conjugative element suggests a mechanism for group II intron dispersal among bacteria. Additional support for this mechanism comes from sequence analysis of the insertion sites of the E.c.I4 family of bacterial group II introns.
Protein-Protein Interactions of Proteins from the ESAT-6 Family ofMycobacterium tuberculosis
Authors: Okkels Limei Meng , Andersen Peter 
Published: April 2004

ABSTRACTIn the present study, we demonstrate that, in analogy with the genes encoding ESAT-6 and CFP-10, the genesrv0287andrv0288from the ESAT-6 gene family are cotranscribed. Using Western-Western blotting and protein-print overlay methodologies, we demonstrate that ESAT-6 and CFP-10, as well as the protein pair Rv0288/Rv0287, interact pairwise in a highly specific way. Most notably, the ESAT-6 proteins interact directly with Rv3873, a possible cell envelope component of the ESAT-6 secretion pathway.
Characterization of Cfa1, a Monofunctional Acyl Carrier Protein Involved in the Biosynthesis of the Phytotoxin Coronatine
Authors: Seidle Heather , Rangaswamy Vidhya , Couch Robin , Bender Carol L. , Parry Ronald J. 
Published: April 2004

ABSTRACT

Cfa1 was overproduced in
Escherichia coli
and
Pseudomonas syringae
, and the degree of 4′-phosphopantetheinylation was determined. The malonyl-coenzyme A:acyl carrier protein transacylase (FabD) of
P. syringae
was overproduced and shown to catalyze malonylation of Cfa1, suggesting that FabD plays a role in coronatine biosynthesis. Highly purified Cfa1 did not exhibit self-malonylation activity.
DY-9760e, a Novel Calmodulin Antagonist, Reduces Infarction after Permanent Focal Cerebral Ischemia in Rats
Authors: Sato Toshiyuki , Takamori Hideo , Shirasaki Yasufumi 
Published: April 2004

DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate), a novel calmodulin antagonist, provides effective protection against Ca<sup>2+</sup> ionophore-induced cytotoxicity and brain injury induced by transient focal ischemia. In this study, we evaluated the effect of DY-9760e on ischemic infarct volume in rats subjected to permanent focal ischemia. DY-9760e (0.5 mg/kg/h for 6 h) significantly reduced the infarct volume when administered immediately after middle cerebral artery occlusion. Furthermore, this neuroprotection was also exerted by treatment with a 3-hour delay, implying that the therapeutic time window for this compound is at least 3 h. In addition, although treatment with 0.1 mg/kg/h for 24 h was ineffective, the combination of a loading dose of 0.3 mg/kg/h for 2 h followed by 0.1 mg/kg/h for 22 h yielded a significant reduction in infarct volume. Thus, prolonged infusion preceded by a loading dose is an efficacious dosing regimen for DY-9760e, especially at a low infusion rate. These data demonstrate the substantial neuroprotective effect of DY-9760e in a permanent focal ischemia model and indicate that this neuroprotectant may be of therapeutic value for the treatment of acute stroke.
Literal and Extended use of Kinship Terms in Documentary Papyri
Authors: Dickey Eleanor 
Published: March 2004

AbstractKinship terms in papyrus letters do not always refer to actual relatives and so pose many problems for modern readers. But by examining all the kinship terms in six centuries of letters it is possible to discover some rules governing the use of kinship terms: in some situations they appear to be always literal, and in others they appear to be almost always extended, though a third group of contexts remains ambiguous. The rules are complex and depend on the particular kinship term involved, the date of writing, the use of names, the position of the kinship term in the letter, and the person to whom it connects the referent.
Egyptian Maat and Hesiodic Metis
Authors: Teeter Emily , Faraone Christopher 
Published: March 2004

AbstractMetis appears twice in the Hesiodic corpus as an anthropomorphic goddess, who is courted and then ingested by Zeus. In the Theogony this narrative ends with the permanent stabilization of his monarchic rule over gods and men. We argue that the myth of Metis and Zeus most probably derives - directly or indirectly - from Egyptian royal ideology, as it is expressed most emphatically in a series of New Kingdom and later (i.e. 1500 BCE-200 CE) texts and relief sculptures that depict the offering to various monarchical male gods of the goddess Maat. Like Hesiodic Mêtis/mêtis, Maat appears in Egyptian texts both as an abstract idea (maat) and as an anthropomorphized goddess Maat and several odd details in the Hesiodic narratives can be explained by Egyptian influence, especially the idea that Zeus swallows Metis and that afterwards she gives him moral guidance. Metis and Egyptian Maat are both closely connected to the idea of legitimate monarchic rule, a relationship that is expressed by the insertion of Maat herself into the coronation names of Egyptian kings, much the same as Metis' name appears in two of the traditional epithets attached to Zeus.
Shear waves in acoustic anisotropic media
Authors: Grechka Vladimir , Zhang Linbin , Rector James W. 
Published: April 2004

Acoustic transversely isotropic (TI) media are defined by artificially setting the shear‐wave velocity in the direction of symmetry axis, VS0, to zero. Contrary to conventional wisdom that equating VS0= 0 eliminates shear waves, we demonstrate their presence and examine their properties. Specifically, we show that SV‐waves generally have finite nonzero phase and group velocities in acoustic TI media. In fact, these waves have been observed in full waveform modeling, but apparently they were not understood and labeled as numerical artifacts.Acoustic TI media are characterized by extreme, in some sense infinite strength of anisotropy. It makes the following unusual wave phenomena possible: (1) there are propagation directions, where the SV‐ray is orthogonal to the corresponding wavefront normal, (2) the SV‐wave whose ray propagates along the symmetry axis is polarized parallel to the P‐wave propagating in the same direction, (3) P‐wave singularities, that is, directions where P‐ and SV‐wave phase velocities coincide might exist in acoustic TI media.We also briefly discuss some aspects of wave propagation in low‐symmetry acoustic anisotropic models. Extreme anisotropy in those media creates bizarre phase‐ and group‐velocity surfaces that might bring intellectual delight to an anisotropic guru.
Development of Polyethylene Copolymers Manufacturing Technologies and Synthesis of New Functionalized Polyolefins with Designed Catalysts
Authors: Imuta Jun-ichi , Todo Akira , Tsutsui Toshiyuki , Hachimori Toshimi , Kashiwa Norio 
Published: April 2004

Abstract
Advanced supported metallocene catalysts for commercialization were developed in the consequence of improving catalyst performances and accomplishing industrial tasks. The relationship between molecular structures and physical properties of ethylene and α-olefin copolymers produced with metallocene catalysts was also investigated. Metallocene catalyzed ethylene/α-olefin copolymers have excellent physical properties (high strength, high clarity, good heat sealability) owing to a homogeneous molecular structure that had never been achieved by conventional Ziegler–Natta catalysts. We have also succeeded in producing long chain branched ethylene copolymers with narrow molecular weight distributions but excellent melt properties by the use of the catalyst technologies to control of the branches in a polymer chain. Moreover, we have found the first example of metallocene-catalyzed allyl alcohol or allylamine incorporation having only one CH2 chain spacer into the nonpolar polymer backbone, using new metallocene and methylaluminoxane with high activity at high temperature. This is the first example of predominant chain end and/or site-selective introduction of polar groups into the polyolefins.