bluuebunny/crossref_metadata_2025 huggingface dataset:
Acceleration of proteolysis during ripening of Cheddar-type cheese using of a streptokinase-producing strain of Lactococcus
Authors: Upadhyay Vivek K , Ravn Peter , Israelsen Hans , Sousa Maria J , Kelly Alan L , McSweeney Paul LH
Published: January 2006

Bovine milk contains a number of indigenous proteolytic enzymes, of which plasmin is the most important (Grufferty & Fox, 1988; Bastian & Brown, 1996; Kelly & McSweeney, 2003). Plasmin (EC 3.4.21.7) is a serine proteinase with pH and temperature optima of 7·5 and 37 °C, respectively. In milk, most of the plasmin is present as its inactive precursor, plasminogen, which is converted to active plasmin by plasminogen activators (PA) present in milk, e.g., urokinase-type (u-PA) and tissue-type PA (t-PA) (Bastian & Brown, 1996). Since plasmin, plasminogen and PA are associated with casein micelles, they are incorporated into cheese curd, while plasmin inhibitors and inhibitors of PA are lost with the whey. Plasmin incorporated in cheese curd acts on its substrate, the caseins, contributing significantly to primary proteolysis during ripening (Upadhyay et al. 2004b).
Editor's Farewell
Authors: Rose J.
Published: January 2006

It is with much regret that I've to resign from the editorship of Robotica after 23 years of service because of ill-health and advanced age. I hope the new editor Greg Chirikjian will make further progress in expanding the scope of the journal and responding to the challenges of our times.
Australian multicentre comparison of subtyping methods for the investigation of Campylobacter infection
Authors: O'REILLY L. C. , INGLIS T. J. J. , UNICOMB L.
Published: January 2006

In order to identify subtyping methods able to contribute to the surveillance or investigation of Australian Campylobacter infection, six genotypic and three phenotypic subtyping methods were evaluated on a collection of 84 clinical isolates collected over a 30-month period from one region in Australia. The aim was to compare the logistics of various subtyping methods and examine their ability to assist in finding outbreaks or common sources of sporadic infection. The genotypic subtyping methods used were sequencing of the short variable region of the flaA gene, two methods using restriction fragment length polymorphism (RFLP) of the flaA gene using either DdeI or EcoRI with PstI, automated ribotyping, pulsed field gel electrophoresis and multilocus sequence typing. The phenotypic methods employed included Laboratory of Enteric Pathogens serotyping, Lior biotyping and antibiotic resistotyping. The level of agreement between subtyping results was determined. Phenotypic methods showed little agreement whereas genotypic typing methods showed a high level of agreement. Using the premise that five of the six genotypic typing methods were in agreement 15 genotypic groupings were identified. Sequencing of the short variable region of the flaA gene, RFLP of the flaA gene or automated ribotyping in conjunction with multilocus sequence typing best identified genotypic groupings. An alternative combination of RFLP of the flaA gene followed by ribotyping was equally satisfactory. RFLP of the flaA gene appeared to be suitable as a preliminary typing method based on ease of operation, equipment availability and cost.
Aquifer operator scaling and the effect on solute mixing and dispersion
Authors: Benson David A. , Meerschaert Mark M. , Baeumer Boris , Scheffler Hans‐Peter
Published: January 2006

Since aquifer parameters may have statistical dependence structures that are present across a huge range of scales, the concepts of fractional Brownian motion (fBm) have been used in both analytic and numerical stochastic settings. Most previous models have used isotropic scaling characterized by a single scalar Hurst coefficient. Any real‐world anisotropy has been handled by an elliptical stretching random K field. We define a d‐dimensional extension of fBm in which the fractional‐order integration may take on different orders in the d primary (possibly nonorthogonal) scaling directions, and the degree of connectivity and long‐range dependence is freely assigned via a probability measure on the unit sphere. This approach accounts for the different scaling found in the vertical versus horizontal directions in sedimentary aquifers and allows very general degrees of continuity of K in certain directions. It also allows for the representation of fracture networks in a continuum setting: The eigenvectors of the scaling matrix describe the primary fracture scaling directions, and discrete weights of fractional integration represent fracture continuity that may be limited to a small number of directions. In a numerical experiment, the motion of solutes through 2‐D “operator‐fractional” Gaussian fields depends very much on transverse Hurst coefficients. Transverse scaling in the range of fractional Gaussian noise engenders greater plume mixing and a transition to a Fickian regime. Higher orders of integration, in the range of fractional Brownian motion, are associated with thicker layering of aquifer sediments and more preferential, unmixed transport. Therefore direct representation of the unique directional scaling properties of an aquifer is important for realistic simulation of transport.
Impact of biomineralization processes on the Mg content of foraminiferal shells: A biological perspective
Authors: Bentov Shmuel , Erez Jonathan
Published: January 2006

The Mg/Ca ratio in foraminiferal shells is widely used as a proxy for paleotemperatures. Nevertheless, it seems that the basic Mg content of foraminifera is determined by biological factors, as can be concluded from the large inter species and intrashell variability and the frequent deviations from inorganic behavior. This paper discusses three possible ways by which foraminifera can control or modify the Mg content in their shell: (1) involvement of organic matrix in the precipitation process that may alter the partition coefficient of Mg in biogenic calcite, (2) controlled conversion of transient amorphous phases to calcite, and (3) modification of the Mg concentration in the parent solution from which the crystals precipitate. The first two mechanisms are probably responsible for the precipitation of high‐Mg calcite phases (whole shell or sublayers), while the third mechanism leads to the formation of low‐Mg calcite phases. We propose a model adapted from epithelial cells that allows massive Mg2+ removal from the biomineralization site. This model is especially relevant to the planktonic and deep benthic low‐Mg foraminifera that are frequently used for paleotemperature reconstructions. We discuss the possible biological roles of Mg in the shell in terms of the calcite polymorph conservation, the in vivo chemical stability of the shell, the functions of Mg as a stabilizer of transient phases and as a controlling agent of the precipitation process. Several temperature sensitive biological processes that may influence the Mg/Ca ratio of the shell are suggested and a model that combines biogenic and inorganic considerations is presented. The model uses Mg heterogeneity in the shell together with temperature response (biologic and inorganic) of biomineralization processes, to account for the deviation of planktonic foraminifera from inorganic calcite at equilibrium with seawater.
A case study of relationship between substorm expansion and global plasma convection
Authors: Liou K. , Ruohoniemi J. M.
Published: January 2006

This letter reports observations of large‐scale ionospheric plasma flows from the SuperDARN radar network and global auroral images from the Polar ultraviolet imager during two large and rare substorm events. The substorm events were characterized by predominantly westward expansion for one and predominantly eastward expansion (or lack of westward expansion) for the other. The westward expansion case was associated with a positive y‐component of interplanetary magnetic field (IMF), whereas the eastward expansion case was associated with a negative y‐component of IMF. The concurrent plasma flow measurements from the SuperDARN radar network suggest that the westward (eastward) expansion is embedded in the large, round dusk (dawn) convection cell. A simple explanation is offered for the observed preponderance of westward expansions, namely, that the pre‐midnight onset location favors the westward plasma flow that is associated with the dusk cell. Eastward expansion occurs only when a large IMF By negative condition causes the midnight sector to be dominated by eastward plasma flows.
Fluctuation effects and monomer-counterion correlations in starlike polyelectrolyte systems
Authors: Jusufi Arben
Published: January 2006

We performed molecular-dynamics simulation to investigate fluctuation effects of monomers and counterions in starlike polyelectrolyte systems. We further study correlations between monomers and counterions. These quantities are systematically studied by variation of two parameters: the functionality f and the degree of dissociation α. Fluctuations of monomers and counterions are quantified by comparing the corresponding form factors of the monomers and counterions with a mean-field approximation. Fluctuations being correlated at length scales of the order of the star radius turn out to be negligible with increasing arm number f of the stars. At small arm numbers where fluctuation effects play a significant role, the use of theoretical mean-field models is questionable for a proper description of the monomer- and counterion-form factors. Correlations between monomers and counterions are quantified by a cross-correlation function. At small degree of dissociation α this function vanishes and indicates weak correlations. Furthermore, we compare our results with theoretical mean-field models. We give an appropriate analysis of the theoretical form factors and test commonly used counterion density distributions with our form factor analysis.
Fabrication and electromechanical properties of a self-actuating Pb(Zr0.52Ti0.48)O3 microcantilever using a direct patternable sol-gel method
Authors: Kang Ghi Yuun , Bae Sang-Woo , Park Hyung-Ho , Kim Tae Song
Published: January 2006

The use of direct-patternable lead zirconate titanate (PZT) films produced using photosensitive stock solutions with ortho-nitrobenzaldehyde and UV (365 nm) irradiation has reached an advanced stage of application in microdetection systems. Electromechanical properties of direct patterned PZT microcantilevers on SiNx∕Ta∕Pt∕PZT∕Pt∕SiO2 structure were measured by a laser vibrometer system as a function of cantilever length. The gravimetric sensitivity of cantilevers in air was characterized by Au deposition, and the mass detecting resolution was 38Hz∕ng. These results suggested a possibility that microelectromechanical systems may be fabricated relatively easily and without high cost processes, for example, by PZT dry etching.
Thermally stable and highly reflective AgAl alloy for enhancing light extraction efficiency in GaN light-emitting diodes
Authors: Kim Ja-Yeon , Na Seok-In , Ha Ga-Young , Kwon Min-Ki , Park Il-Kyu , Lim Jae-Hong , Park Seong-Ju , Kim Min-Ho , Choi Dongyoul , Min Kyeongik
Published: January 2006

The properties of a AgAl alloy reflector layer deposited on a p-GaN layer for use in high-efficiency GaN flip-chip light-emitting diodes (FCLEDs) were investigated. The AgAl layer showed good adhesion properties compared to a layer of Ag on p-GaN. In addition, no agglomeration was found, indicating that the AgAl layer is thermally stable due to the formation of oxidized Al on the surface and at the interface of the AgAl layer. The InGaN∕GaN multiquantum well light-emitting diode with the annealed AgAl layer showed good I-V characteristic and an enhanced optical output power compared to that with an annealed Ag layer due to the high reflectivity (86.7% at 465 nm), smooth surface after annealing, and good Ohmic property of AgAl. These results clearly indicate that a AgAl layer on p-GaN constitutes a promising reflector and Ohmic scheme for achieving high-brightness FCLEDs.
ProteomeCommons.org JAF: reference information and tools for proteomics
Authors: Falkner J. A. , Falkner J. W. , Andrews P. C.
Published: January 2006

Summary: Analysis of proteomics data, specifically mass spectrometry data, commonly relies on libraries of known information such as atomic masses, known stable isotopes, atomic compositions of amino acids, observed modifications of known amino acids and ion masses that directly correspond to known amino acid sequences. The Java Analysis Framework (JAF) for proteomics provides a freely usable, open-source library of Java code that abstracts all of the aforementioned data, enabling more rapid development of proteomics tools. The JAF also includes several user tools that can be run directly from a web browser.

Availability: The current version and an archive of all older versions of the Java Analysis Framework for Proteomics is freely available, including complete source-code, at

Contact:  jfalkner@umich.edu
Comparative analysis of antibiotic resistance gene markers in Mycoplasma genitalium: application to studies of the minimal gene complement
Authors: Pich Oscar Q. , Burgos Raul , Planell Raquel , Querol Enrique , Piñol Jaume
Published: January 2006

Mycoplasma genitalium has been proposed as a suitable model for an in-depth understanding of the biology of a free-living organism. This paper reports that the expression of the aminoglycoside resistance gene aac(6′)-aph(2″), the only selectable marker hitherto available for M. genitalium genetic studies, correlates with a growth impairment of the resistant strains. In light of this finding, a tetM438 construction based on the tetracycline resistance gene tetM was developed; it can be used efficiently in M. genitalium and confers multiple advantages when compared to aac(6′)-aph(2″). The use of tetM438 significantly improves transformation efficiency and generates visible colonies faster. Finally, the improvements in the pMTnTetM438 construction made it possible to obtain insertions in genes which have not been previously considered to be dispensable under laboratory growth conditions.
To have neighbour's fare: extending the molecular toolbox for Streptococcus pneumoniae
Authors: Kloosterman Tomas G. , Bijlsma Jetta J. E. , Kok Jan , Kuipers Oscar P.
Published: January 2006

In past years, several useful genetic tools have been developed to study the molecular biology of Streptococcus pneumoniae. In order to extend the existing spectrum of tools, advantage was taken of the toolbox originally developed for the closely related bacterium Lactococcus lactis, which was adapted for the manipulation of S. pneumoniae. The modified tools are as follows. (i) An improved nisin-inducible (over)expression system (NICE). The nisRK genes, encoding a two-component system essential for transcriptional activation in response to nisin, were integrated into the bgaA locus of S. pneumoniae D39. In this strain, D39nisRK, addition of nisin resulted in the overexpression of several genes placed under the control of the nisin-inducible promoter, while no detectable expression was observed in the absence of nisin. (ii) A lacZ reporter system. Using strain D39nisRK, which lacks endogenous β-galactosidase activity, the usefulness of the lacZ reporter vector pORI13 for the generation of chromosomal transcriptional fusions was demonstrated. In addition, the repA gene, necessary for the replication of pORI13, was introduced into the bgaA locus, thereby generating a background for plasmid-based promoter expression studies. (iii) A simplified chemically defined medium, which supports growth of all sequenced S. pneumoniae strains to a level comparable to that in complex medium. (iv) A system for the introduction of unmarked deletions and mutations into the chromosome, which is independent of the genotype of the target strain. Most of these systems were successfully applied in strains R6 and TIGR4 as well. In addition, the tools offer several improvements and advantages compared to existing ones. Thus, the molecular toolbox for S. pneumoniae has been successfully extended.
Innate immunity and the pneumococcus
Authors: Paterson Gavin K. , Mitchell Tim J.
Published: January 2006

The innate immune system provides a non-specific first line of defence against microbes and is crucial both in the development and effector stages of subsequent adaptive immune responses. Consistent with its importance, study of the innate immune system is a broad and fast-moving field. Here we provide an overview of the recent key advances made in this area with relation to the important pathogenStreptococcus pneumoniae(the pneumococcus).
Key worker services for disabled children: what characteristics of services lead to better outcomes for children and families?
Authors: Sloper P. , Greco V. , Beecham J. , Webb R.
Published: January 2006

Background  Research has shown that families of disabled children who have a key worker benefit from this service and recent policy initiatives emphasize the importance of such services. However, research is lacking on which characteristics of key worker schemes for disabled children are related to better outcomes for families.

Methods  A postal questionnaire was completed by 189 parents with disabled children who were receiving a service in seven key worker schemes in England and Wales. Path analysis was used to investigate associations between characteristics of the services and outcomes for families (satisfaction with the service, impact of key worker on quality of life, parent unmet need, child unmet need).

Results  The four path models showed that key workers carrying out more aspects of the key worker role, appropriate amounts of contact with key workers, regular training, supervision and peer support for key workers, and having a dedicated service manager and a clear job description for key workers were associated with better outcomes for families. Characteristics of services had only a small impact on child unmet need, suggesting that other aspects of services were affecting child unmet need.

Conclusions  Implications for policy and practice are discussed, including the need for regular training, supervision and peer support for key workers and negotiated time and resources for them to carry out the role. These influence the extent to which key workers carry out all aspects of the key worker's role and their amount of contact with families, which in turn impact on outcomes.
Assortative preferences and discrimination by females against hybrid male song in the grasshoppers Chorthippus brunneus and Chorthippus jacobsi (Orthoptera: Acrididae)
Authors: Bridle J. R. , Saldamando C. I. , Koning W. , Butlin R. K.
Published: January 2006

The grasshoppers Chorthippus brunneus and Chorthippus jacobsi are highly differentiated for male mating signals, and form a mosaic hybrid zone in northern Spain. At some sites within this zone, many hybrids are observed. At others, few hybrids are observed. Such bimodal sites may reflect recent contacts between parental genotypes, or local variation in levels of assortative mating or selection against hybrids. Playback of 12 parental and F1 male songs to 296 parental and hybrid females revealed positive assortative preferences in C. brunneus and C. jacobsi females, supporting a direct role of male mating signals in female choice. However, all female genotypic classes showed reduced responsiveness to F1 male songs. Such sexual selection against hybrids is consistent with the narrow cline width observed in the field for song characters relative to morphology. These results have implications for the genetic structure of the hybrid zone and for models of speciation by reinforcement.
Hepatic cavernous hemangioma: underrecognized associated histologic features
Authors: Kim Grace E. , Thung Swan N. , Tsui Wilson M. S. , Ferrell Linda D.
Published: January 2006

Abstract: Background/Aims: Cavernous hemangiomas (CH) are typically described as solitary, well‐circumscribed lesions and are reported to have a distinct fibrous interface. This study describes underrecognized histological changes of large hepatic hemangiomas that contradict this long‐standing view.

Methods: Nineteen cases of hepatic resections for CH were reviewed. Stains for estrogen and progesterone receptors (ER/PR), MIB‐1, α‐smooth muscle actin, collagen IV, and elastic Van Gieson stains were applied to the lesions.

Results: The CHs measured 5–31 cm (mean 16.6 cm). Sixteen (84%) CHs had an irregular interface with the liver parenchyma while only three had the well‐defined fibrous capsule typically described for CH. Fifteen (79%) CHs had dilated vascular spaces filled with blood 0.1–2.0 cm beyond the confines of the main CH, which we have designated hemangioma‐like vessels (HLVs). The histochemical and immunohistochemical stains in both CH and HLVs were similar, with the walls of the vessels composed predominantly of collagen with some faint elastic fibers and smooth muscle, endothelium underlined by collagen IV, negative ER/PR in all components, and a proliferation rate of <5/100 endothelial cells.

Conclusion: Irregular edges of CH and HLVs in the liver parenchyma adjacent to CH have been underrecognized. No significant differences in staining or proliferative rate were present between CHs and HLVs, suggesting the HLVs are within the spectrum of CH.
Treatment of rectovaginal fistula: A 5‐year review
Authors: CASADESUS Damian , VILLASANA Luis , SANCHEZ Ines M. , DIAZ Hector , CHAVEZ Mariano , DIAZ Angelina
Published: January 2006

This paper presents a chart review of 17 patients who had been treated for rectovaginal fistula (RVF) from 1996 to 2000. In most cases (13; 76.5%), the fistula was the result of post‐surgical complications. Following vaginal mucosa advancement flap repair or repair after conversion to a fourth‐degree perineal laceration, 16 (94%) of the rectovaginal fistulae (during the first attempted repair or after failed treatment) were successfully treated. In all patients but one, faecal diversion was avoided. In two patients, fistulography was both a diagnostic procedure and the method of treatment.
Ego Development and Adolescent Academic Achievement
Authors: Bursik Krisanne , Martin Timothy A.
Published: January 2006

This study investigated ego developmental differences in adolescent academic orientations and academic achievement. A sample of 142 male and female high school students completed the Washington University Sentence Completion Test and self‐report measures assessing academic locus of control, learning orientation (LO), and grade orientation (GO). With increasing ego development, adolescents demonstrated increased internal academic locus of control, stronger LOs, diminished GOs, and higher class rank. Regression analysis indicated that ego level was a significant predictor of academic achievement after controlling for the effects of verbal intelligence and gender. Implications for fostering academic success through theoretically relevant interventions are discussed.
Continuous Murmur Due to a Mediastinal Tumor
Authors: Tufekcioglu Omac , Yildirim Nesligul , Karabal Orhan , Maden Orhan , Bicer Asuman , Altay Hakan , Gunel Emre Nuri
Published: January 2006

Despite the lengthy differential diagnosis of causes of cardiac murmurs, the association of a mediastinal mass and a continuous murmur is very rare. We report herein a case of a mediastinal tumor and continuous murmur where transthoracic echocardiography provided clear differential diagnosis and demonstrated the cause of murmur.
Use of the Ejection Fraction‐Velocity Ratio in the Hemodynamic Assessment of Aortic Bioprosthetic Valves
Authors: Antonini‐Canterin Francesco , Allocca Giuseppe , Rivaben Dante , Korcova‐Miertusova Renata , Pezzutto Norma , Pascotto Andrea , Cervesato Eugenio , Pavan Daniela , Piazza Rita , Nicolosi Gian Luigi
Published: January 2006

Background: A new echocardiographic severity index of aortic valve stenosis has been recently introduced: the ejection fraction‐velocity ratio (EFVR), which is a simple ratio ejection fraction/4Vmax2. This nonflow corrected index demonstrated an excellent accuracy in quantifying the effective orifice area (EOA) in native aortic valves. There is no information about the reliability of EFVR in assessing aortic EOA in patients with bioprostheses. Methods: In 141 consecutive patients with aortic bioprostheses (85 males, mean age 74 ± 9 years), EOA was calculated by both continuity equation (CE) and EFVR. Results: The correlation between CE and EFVR was highly significant (r = 0.88; P < 0.0001). The area under the receiver operating characteristic (ROC) curve was 0.97 (considering a positive case CE < 1.0 cm2, best cutoff of EFVR was <1.06). Using CE as gold standard and a cutoff of 1.0 for both indexes, EFVR showed good sensitivity (80%) and specificity (98%). Also in a subgroup of 46 patients with moderate or severe mitral regurgitation, the EFVR had a good diagnostic accuracy (sensitivity 89%, specificity 97%). In 91 patients with ejection fraction ≤ 50%, the EFVR confirmed good sensitivity (79%) and specificity (97%). Conclusions: The EFVR, a simple and not time‐consuming index, demonstrated a good diagnostic accuracy in assessing EOA also in patients with aortic bioprostheses. The presence of moderate to severe mitral regurgitation or left ventricular dysfunction does not reduce significantly the reliability of this new index. The EFVR can be taken into consideration in the clinical practice, at least when CE measurements are technically difficult.
The Process of Policy Innovation: Prison Sitings in Rural North Carolina
Authors: Hoyman Michele , Weinberg Micah
Published: January 2006

We gauge the relative impact of economics, demographics, and politics on the decisions of 79 rural North Carolina counties whether to site a prison in the period 1970–2000. The results of this model demonstrate that, contrary to the expectation that counties site prisons in response to economic distress, the demographic characteristics of each county affect the relative likelihood of a prison siting more than its economics does. The influential demographic predictors are those inextricably bound up with development options—the education levels of its citizens—and those that limit its ability to pursue controversial projects—its not‐in‐my‐backyard (NIMBY) constituencies—rather than those that measure its racial diversity. Therefore, prison siting is neither a simple story of economic determinism nor one of environmental racism. We use a proportional hazards regression to model this innovation adoption in response to the challenge to select methods that take the potential time dependence of adoptions into account. A duration model is also particularly suitable for cases such as this one for which the innovation adoption is better understood as a process than as an event.
Hexadecylphosphocholine (Miltefosine) Has Broad-Spectrum Fungicidal Activity and Is Efficacious in a Mouse Model of Cryptococcosis
Authors: Widmer Fred , Wright Lesley C. , Obando Daniel , Handke Rosemary , Ganendren Ranjini , Ellis David H. , Sorrell Tania C.
Published: January 2006

The alkyl phosphocholine drug miltefosine is structurally similar to natural substrates of the fungal virulence determinant phospholipase B1 (PLB1), which is a potential drug target. We determined the MICs of miltefosine against key fungal pathogens, correlated antifungal activity with inhibition of the PLB1 activities (PLB, lysophospholipase [LPL], and lysophospholipase-transacylase [LPTA]), and investigated its efficacy in a mouse model of disseminated cryptococcosis. Miltefosine inhibited secreted cryptococcal LPTA activity by 35% at the subhemolytic concentration of 25 μM (10.2 μg/ml) and was inactive against mammalian pancreatic phospholipase A2 (PLA
2
). At 250 μM, cytosolic PLB, LPL, and LPTA activities were inhibited by 25%, 51%, and 77%, respectively. The MICs at which 90% of isolates were inhibited (MIC
90
s) against
Candida albicans
,
Candida glabrata
,
Candida krusei
,
Cryptococcus neoformans
,
Cryptococcus gattii
,
Aspergillus fumigatus
,
Fusarium solani
,
Scedosporium prolificans
, and
Scedosporium apiospermum
were 2 to 4 μg/ml. The MICs of miltefosine against
Candida tropicalis
(
n
= 8) were 2 to 4 μg/ml, those against
Aspergillus terreus
and
Candida parapsilosis
were 8 μg/ml (MIC
90
), and those against
Aspergillus flavus
(
n
= 8) were 2 to 16 μg/ml. Miltefosine was fungicidal for
C. neoformans
, with rates of killing of 2 log units within 4 h at 7.0 μM (2.8 μg/ml). Miltefosine given orally to mice on days 1 to 5 after intravenous infection with
C. neoformans
delayed the development of illness and mortality and significantly reduced the brain cryptococcal burden. We conclude that miltefosine has broad-spectrum antifungal activity and is active in vivo in a mouse model of disseminated cryptococcosis. The relatively small inhibitory effect on PLB1 enzyme activities at concentrations exceeding the MIC by 2 to 20 times suggests that PLB1 inhibition is not the only mechanism of the antifungal effect.
Rifalazil Pretreatment of Mammalian Cell Cultures Prevents Subsequent Chlamydia Infection
Authors: Suchland Robert J. , Brown Kara , Rothstein David M. , Stamm Walter E.
Published: January 2006

Chlamydia
species are widely disseminated obligate intracellular pathogens that primarily cause urogenital, ocular, and respiratory infections. In these studies, we show that exposing mammalian cells to antibacterial agents prior to
Chlamydia
inoculation protects the host cells against subsequent challenge by chlamydiae (the protective effect [PE]). Rifalazil exhibited a considerably stronger PE than did azithromycin, rifampin, doxycycline, and ofloxacin. Specifically, 0.002 μg/ml rifalazil incubated for 1 day with a monolayer of McCoy cells was sufficient to protect against a challenge 2 days later with
Chlamydia trachomatis
serovar D (UW-3). The PE was observed with five different mammalian cell lines and with a variety of
C. trachomatis
and
Chlamydia pneumoniae
isolates. The duration of the PE was 6 to 12 days for rifalazil (depending on the cell line), a maximum of 3 days for azithromycin, and less than a day for the other drugs tested. For rifalazil, the PE was shown to be mediated by inhibition of the chlamydial RNA polymerase since mutants with altered RNA polymerases had correspondingly altered PEs. These results suggest that rifalazil may be unique in its ability to prevent infection with obligate intracellular pathogens for a considerable time after treatment. This characteristic may be of particular public health value in reducing reinfection with chlamydiae.
Nonmolecular Test for Detection of Low-Level Resistance to Fluoroquinolones in
Streptococcus pneumoniae
Authors: Varon Emmanuelle , Houssaye Serge , Grondin Sophie , Gutmann Laurent
Published: January 2006

With respect to pneumococci, there is a need to detect first-step mutants with reduced fluoroquinolone (FQ) susceptibility from which second-step, resistant mutants are likely to be selected in the presence of antipneumococcal FQs. Here, we describe an interpretative disk diffusion test, of which three options are presented, that allows the distinction between first- and second-step mutants. Using five FQ disks (pefloxacin, norfloxacin, levofloxacin, ciprofloxacin, and sparfloxacin, option 1), all known mechanisms of altered FQ susceptibility found in first-step mutants (ParC, ParE, GyrA, or efflux) and in second-step mutants (ParC and GyrA or ParE and GyrA) can be accurately detected, making this option a useful epidemiological tool. Using three FQ disks (pefloxacin, norfloxacin, and levofloxacin, option 2), the most prevalent FQ-resistant mutants, but not the first-step GyrA mutants, can be detected. With only two FQ disks (norfloxacin and levofloxacin) in the third and simplest option, first-step mutants can be distinguished from second-step mutants, however, without differentiation of ParC, ParE, or efflux alterations.
Pharmacokinetics of Enfuvirtide in Patients Treated in Typical Routine Clinical Settings
Authors: Stocker Hartmut , Kloft Charlotte , Plock Nele , Breske Antje , Kruse Guido , Herzmann Christian , Schulbin Hubert , Kreckel Peter , Weber Christoph , Goebel Frank , Roeling Joerg , Staszewski Schlomo , Plettenberg Andreas , Moecklinghoff Christiane , Arastéh Keikawus , Kurowski Michael
Published: January 2006

Therapeutic drug monitoring (TDM) is gaining importance for improving the success of antiretroviral treatment in human immunodeficiency virus-infected patients. However, enfuvirtide (ENF) concentrations are not regularly determined. The objective of this work was to study the pharmacokinetics (PK) of ENF in patients treated in routine clinical settings, to develop a population PK model describing the concentration-time profile, and to establish PK reference values. A liquid chromatography-tandem mass spectrometry method was developed and applied to serum samples submitted for TDM. A two-compartment model with linear absorption and elimination was fitted to 329 concentrations from 131 patients. The PK model was used for simulations resulting in percentile curves for ENF levels for the full dosing interval. The model predicted that a median concentration of 1,968 ng/ml would be reached 12 h after administration of 90 mg of ENF, and 23% and 58% of patients are expected to have concentrations below 1,000 ng/ml and 2,200 ng/ml, respectively. Both values have been proposed as cutoffs for virological efficacy. The median maximum concentration of drug in serum (Cmax) of 3,943 ng/ml, predicted for 3 h after drug administration, is lower than theCmaxreported previously. We found an enormous interpatient variability at every time point, with concentration spectrums covering >1 log and 52% and 123% interindividual variabilities in the typical clearance and volume of distribution, respectively, in contrast to preexisting PK data. In summary, ENF levels are lower and more variable than expected. Many patients may achieve insufficient concentrations. Further covariate analysis in the population PK model might help to identify factors influencing the variability in ENF concentrations.
Pharmacokinetic-Pharmacodynamic Comparison of Amphotericin B (AMB) and Two Lipid-Associated AMB Preparations, Liposomal AMB and AMB Lipid Complex, in Murine Candidiasis Models
Authors: Andes D. , Safdar N. , Marchillo K. , Conklin R.
Published: January 2006

It is generally accepted that the lipid formulations of amphotericin B (AMB) are not as potent as conventional AMB on a milligram-per-kilogram basis. We used a neutropenic murine disseminated candidiasis model to compare the in vivo potencies of AMB, liposomal AMB (L-AMB), and AMB lipid complex (ABLC) pharmacodynamically. The pharmacokinetics of the antifungals were examined in serum and in three organs commonly seeded in disseminated candidiasis (kidneys, liver, and lung). Both single-dose time-kill studies and multiple-dosing-regimen studies were used with each of the compounds. Determinations of the numbers of CFU in the kidneys were performed following the administration of three escalating single doses of the polyenes at various times over 48 h. The areas under the time-kill curves (AUTKs) for each dose level of the drugs were compared by analysis of variance (ANOVA). In the multiple-dosing-regimen studies with five
Candida
isolates, AMB, L-AMB, and ABLC were administered daily for 72 h. The organism burdens in the mouse kidneys were similarly used as the treatment end point. Additional multiple regimen-dosing-studies were performed with a single
Candida albicans
isolate, and the microbiologic outcomes in four internal organs (kidneys, liver, spleen, and lung) were examined at the end of therapy (48 h). The relationship between the dose and the drug exposure expressed by the pharmacokinetics of the dosing regimens in serum and organ tissue were analyzed by using a maximum-effect model. ANOVA was used to compare the drug exposures necessary to achieve the 25% effective dose (ED
25
), ED
50
, ED
75
, and 1 log
10
killing. Comparison of AUTKs suggested that AMB was 4.3- to 5.9-fold more potent than either ABLC or L-AMB. The time-kill curves for both lipid formulations were very similar. In the multiple-dosing-regimen studies, AMB was 5.0- to 8.0-fold more potent than each of the lipid formulations against five
Candida
isolates in the kidneys. Similar differences in potency (5.1- to 7.2-fold) were observed in the other end organs. The difference in pharmacokinetics in serum accounted for much of the difference in potency between AMB and ABLC (ratio of serum ABLC area under the curve of effective doses to serum AMB area under the curve of effective doses, 1.2). The differences in the kinetics in the various end organs between AMB and L-AMB were better at explaining the disparate potencies at these infection sites (ratio of organ L-AMB area under the curve of effective doses to organ AMB area under the curve of effective doses, 1.1).
Distribution of Tetracycline Resistance Genes in
Actinobacillus pleuropneumoniae
Isolates from Spain
Authors: Blanco Mónica , Gutiérrez-Martin César B. , Rodríguez-Ferri Elías F. , Roberts Marilyn C. , Navas Jesús
Published: January 2006

Actinobacillus pleuropneumoniae
is the etiological agent of porcine pleuropneumonia. Tetracycline is used for therapy of this disease, and
A. pleuropneumoniae
carrying the
tet
(B) gene, coding for an efflux protein that reduces the intercellular tetracycline level, has been described previously. Of the 46 tetracycline-resistant (Tc
r
) Spanish
A. pleuropneumoniae
isolates used in this study, 32 (70%) carried the
tet
(B) gene, and 30 of these genes were associated with plasmids. Eight (17%) isolates carried the
tet
(O) gene, two (4%) isolates carried either the
tet
(H) or the
tet
(L) gene, and all these genes were associated with plasmids. This is the first description of these
tet
genes in
A. pleuropneumoniae
. The last two Tc
r
isolates carried none of the
tet
genes examined. Except for 
tet
(O)-containing plasmids, the other 34 Tc
r
plasmids were transformable into an
Escherichia coli
recipient. Two plasmids were completely sequenced. Plasmid p11745, carrying the
tet
(B) gene, was 5,486 bp and included a
rep
gene, encoding a replication-related protein, and two open reading frames (ORFs) with homology to mobilization genes of
Neisseria gonorrhoeae
plasmid pSJ7.4. Plasmid p9555, carrying the
tet
(L) gene, was 5,672 bp and, based on its G+C content, consisted of two regions, one of putative gram-positive origin containing the
tet
(L) gene and the other comprising four ORF
s
organized in an operon-like structure with homology to mobilization genes in other plasmids of gram-negative bacteria.
Inhibition of
Candida parapsilosis
Mitochondrial Respiratory Pathways Enhances Susceptibility to Caspofungin
Authors: Chamilos Georgios , Lewis Russell E. , Kontoyiannis Dimitrios P.
Published: January 2006

Among the
Candida
species,
Candida parapsilosis
has a unique mitochondrial respiratory network. The addition of inhibitors of the respiratory pathways in three clinical isolates of
C. parapsilosis
with high (≥2- μg/ml) MICs of caspofungin significantly (fivefold) decreased caspofungin MICs but did not change fluconazole MICs.
FILTERS, MIRRORS AND MICROCAVITIES FROM POROUS SILICON
Authors: AGARWAL V. , DEL RÍO J. A.
Published: January 2006

In this paper we report the detailed fabrication and experimental characterization of porous silicon one-dimensional photonic bandgap structures for specific photonic applications. These structures have been prepared on silicon substrate as well as free standing and can be proven useful for a large variety of applications such as high quality dielectric mirrors and filters.
Effects of the presence, absence, and overexpression of uncoupling protein-3 on adiposity and fuel metabolism in congenic mice
Authors: Costford Sheila R. , Chaudhry Shehla N. , Salkhordeh Mahmoud , Harper Mary-Ellen
Published: January 2006

Uncoupling protein-3 (UCP3) is a poorly understood mitochondrial inner membrane protein expressed predominantly in skeletal muscle. The aim of this study was to examine the effects of the absence or constitutive physiological overexpression of UCP3 on whole body energy metabolism, glucose tolerance, and muscle triglyceride content. Congenic male UCP3 knockout mice ( Ucp3 −/−), wild-type, and transgenic UCP3 overexpressing (UCP3Tg) mice were fed a 10% fat diet for 4 or 8 mo after they were weaned. UCP3Tg mice had lower body weights and were less metabolically efficient than wild-type or Ucp3 −/− mice, but they were not hyperphagic. UCP3Tg mice had smaller epididymal white adipose tissue and brown adipose tissue (BAT) depots; however, there were no differences in muscle weights. Glucose and insulin tolerance tests revealed that both UCP3Tg and Ucp3 −/− mice were protected from development of impaired glucose tolerance and were more sensitive to insulin. 2-Deoxy-d-[1-3H]glucose tracer studies showed increased uptake of glucose into BAT and increased storage of liver glycogen in Ucp3 −/− mice. Assessments of intramuscular triglyceride (IMTG) revealed decreases in quadriceps of UCP3Tg mice compared with wild-type and Ucp3 −/− mice. When challenged with a 45% fat diet, Ucp3 −/− mice showed increased accumulation of IMTG compared with wild-type mice, which in turn had greater IMTG than UCP3Tg mice. Results are consistent with a role for UCP3 in preventing accumulation of triglyceride in both adipose tissue and muscle.
Cellular prion protein is released on exosomes from activated platelets
Authors: Robertson Catherine , Booth Stephanie A. , Beniac Daniel R. , Coulthart Michael B. , Booth Timothy F. , McNicol Archibald
Published: January 2006

Cellular prion protein (PrPC) is a glycophosphatidylinositol (GPI)–anchored protein, of unknown function, found in a number of tissues throughout the body, including several blood components of which platelets constitute the largest reservoir in humans. It is widely believed that a misfolded, protease-resistant form of PrPC, PrPSc, is responsible for the transmissible spongiform encephalopathy (TSE) group of fatal neurodegenerative diseases. Although the pathogenesis of TSEs is poorly understood, it is known that PrPC must be present in order for the disease to progress; thus, it is important to determine the physiologic function of PrPC. Resolving the location of PrPC in blood will provide valuable clues as to its function. PrPC was previously shown to be on the alpha granule membrane of resting platelets. In the current study platelet activation led to the transient expression of PrPC on the platelet surface and its subsequent release on both microvesicles and exosomes. The presence of PrPC on platelet-derived exosomes suggests a possible mechanism for PrPC transport in blood and for cell-to-cell transmission.
Dehydrative Glycosylation in Water Using a Brønsted Acid–Surfactant-Combined Catalyst
Authors: Aoyama Naohiro , Kobayashi Shu
Published: January 2006

Brønsted acid–surfactant-combined catalyst, dodecylbenzenesulfonic acid (DBSA), was used in catalytic dehydrative glycosylation reactions in water. 1-Hydroxy sugars, such as O-benzyl-protected furanose and pyranose, reacted with alcohols and a nitrogen nucleophile in the presence of a catalytic amount of DBSA to afford the desired adducts in good yields. Detailed study of the glycosylation of 2-deoxy-d-ribofuranose showed that hydrophobicity of the substrates was important to attain higher yields. Regarding the α/β selectivities, d-ribose and d-mannose derivatives gave the products in high β- and α-selectivities, respectively.
Temporal Dynamics and Latency Patterns of Receptor Neuron Input to the Olfactory Bulb
Authors: Spors Hartwig , Wachowiak Matt , Cohen Lawrence B. , Friedrich Rainer W.
Published: January 2006

Odorants are first represented in the brain by distributed patterns of activity in the olfactory bulb (OB). Although neurons downstream of sensory inputs respond to odorants with temporally structured activity, sensory inputs to glomeruli are typically described as static maps. Here, we imaged the temporal dynamics of receptor neuron input to the OB with a calcium-sensitive dye in the olfactory receptor nerve terminals in anesthetized mice. We found that diverse, glomerulus- and odorant-dependent temporal dynamics are present even at this initial input stage. Instantaneous spatial patterns of receptor input to glomeruli changed both within and between respiration cycles. Glomerular odorant responses differed in amplitude, latency, rise time, and degree of modulation by sniffing in an odorant-specific manner. Pattern dynamics within the first respiration cycle recurred in a similar manner during consecutive cycles. When sniff rate was increased artificially, pattern dynamics were preserved in the first sniff but were attenuated during subsequent sniffs. Temporal response properties were consistent across individuals on a coarse regional scale and on a fine scale of individual glomeruli. Latency and magnitude of glomerular inputs were only weakly correlated and might therefore convey independent odorant information. These data demonstrate that glomerular maps of primary sensory input to the OB are temporally dynamic. These dynamics may contribute to the representation of odorant information and affect information processing in the central olfactory system of rodents.
Novel Blockade of Protein Kinase A-Mediated Phosphorylation of AMPA Receptors
Authors: Vanhoose Amanda M. , Clements Julie M. , Winder Danny G.
Published: January 2006

The phosphorylation state of the glutamate receptor subtype 1 (GluR1) subunit of the AMPA receptor (AMPAR) plays a critical role in synaptic expression of the receptor, channel properties, and synaptic plasticity. Several Gs-coupled receptors that couple to protein kinase A (PKA) readily recruit phosphorylation of GluR1 at S845. Conversely, activation of the ionotropic glutamate NMDA receptor (NMDAR) readily recruits dephosphorylation of the same GluR1 site through Ca2+-mediated recruitment of phosphatase activity. In a physiological setting, receptor activation often overlaps and crosstalk between coactivation of multiple signaling cascades can result in differential regulation of a given substrate. After investigating the effect of coactivation of the NMDAR and the Gs-coupled β-adrenergic receptor on GluR1 phosphorylation state, we have observed a novel signal that prevents PKA-mediated phosphorylation of GluR1 at serine site 845. This blockade of GluR1 phosphorylation is dependent on cellular depolarization recruited by either NMDAR or AMPAR activation, independent of Ca2+and independent of calcineurin, protein phosphatase 1, and/or protein phosphatase 2A activity. Thus, in addition to the typical kinase–phosphatase rivalry mediating protein phosphorylation state, we have identified a novel form of phospho-protein regulation that occurs at GluR1 and may also occur at several other PKA substrates.
Durability properties of low-resistance self-compacting concrete
Authors: Assié S. , Escadeillas G. , Marchese G. , Waller V.
Published: January 2006

The building industry is turning increasingly to the use of self-compacting concrete (SCC) in order to improve many aspects of building construction: SCC offers several advantages in technical, economic, environmental and human terms. However, there are still some problems with regard to its durability, in terms of physical and chemical properties. The purpose of this research project is to study various durability characteristics of SCC compared with reference samples of vibrated concrete (VC) with similar low compressive strength. For this purpose, SCC and VC mixes were prepared using the same ingredients in identical proportions, the only difference being that limestone filler was used for the SCC mixes. Tests carried out on these samples revealed that there was no significant difference in the physico-chemical properties (oxygen permeability, chloride diffusion, water absorption, carbonation and leaching by ammonium nitrate) of the two types of concrete.