bluuebunny/crossref_metadata_2025 huggingface dataset:
Antimicrobial resistance of Shigella flexneri serotypes in Israel during a period of three years: 2000–2002
Authors: VASILEV V. , JAPHETH R. , YISHAI R. , ANDORN N.
Published: November 2004

This is a surveillance study of the antimicrobial resistance of the S. flexneri group in the context of its serotype diversity. It includes 1422 isolates, which were sent to the National Shigella Reference Centre (NSRC) by hospitals and outpatient clinics in Israel during a 3-year period (2000–2002). The strains were identified and classified according to the prevalence and antigenic structure of their serotypes. All samples were checked for resistance to ampicillin (AMP), trimethoprim–sulphamethoxazole (TMP–SMX), ceftriaxone (CRO), tetracycline (TE), nalidixic acid (NAL), and chloramphenicol (C) by the disk diffusion method of Bauer et al. There were significant differences in their resistance to the individual antimicrobials with resistance to AMP, TE and C being lower among the strains of serotype 6 than among those of serotypes 2a and 1b. The resistant phenotypes were also serotype-specific. The similarities both in individual and in phenotype resistance between the rare and the prevalent serotypes (but not serotype 6) may be attributed to their antigenic relatedness. The serospecificity of the antimicrobial resistance was not affected by external factors such as seasonality and source (hospital or outpatient laboratory) of the isolates, and the age and sex of the patients. The serotype-specific approach can assist in properly assessing the problem of the antimicrobial resistance of the Shigella flexneri group and may prove useful for the empirical therapy of shigellosis. The observed interdependency between resistance and the antigenic specificity and relatedness of the S. flexneri serotypes requires additional investigation.
Influenza and pneumonia hospitalizations in Ontario: a time-series analysis
Authors: CRIGHTON ERIC J. , MOINEDDIN RAHIM , MAMDANI MUHAMMAD , UPSHUR ROSS E. G.
Published: November 2004

A comprehensive examination of gender and age-specific influenza and pneumonia hospitalization seasonality is currently lacking. Using population-based data for Ontario, Canada between April 1988 and March 2002 (n=339803 hospitalizations), findings from this study revealed clear seasonality [Fisher's Kappa (FK) test=68·64, P<0·001; Bartlett's Kolmogorov–Smirnov (BKS) test=0·68, P<0·001] with consistent summer troughs and winter peaks for both sexes and all ages combined. The very young (both sexes 0–4 years) demonstrated the strongest seasonality (Rautoreg2=0·97) and females aged 10–19 years, the weakest (Rautoreg2=0·59). Gender differences were most pronounced in the oldest age groups (80+ years) where females had an average annualized peak rate of 250/100000 compared to 400/100000 for males. These findings can contribute to more population-specific prevention strategies and effective resource and service allocation based on seasonal and specific population demands.
Notice of inadvertent duplicate publication
Authors: NOAH NORMAN , SWANSON GAVIN
Published: November 2004

It has come to our notice that a paper we published in Epidemiology & Infection contained a substantial amount of previously published material.
Lassen sich hyperkinetische Auffälligkeiten am Nachmittag durch eine Morgengabe von Methylphenidat Retard vermindern?
Authors: Sinzig Judith K. , Döpfner Manfred , Plück Julia , Banaschewski Tobias , Stephani Ulrich , Lehmkuhl Gerd , Rothenberger Aribert , Methylphenidat Arbeitsgruppe
Published: November 2004

Zusammenfassung: Fragestellung: Neuere galenische Zubereitungen erlauben es, langzeitwirksame Methylphenidatpräparate mit einer zweistufigen Freisetzungsdynamik herzustellen und so durch eine morgendliche Einmalgabe der Unterstützung von Schulkindern mit Aufmerksamkeitsdefizit-/Hyperaktitivätsstörung (ADHS) besser gerecht zu werden. Die Studie analysiert die Wirksamkeit von Medikinet®-Retard, einem neuen retardierten Methylphenidat-Präparat, bei der Veränderung der ADHS-Symptomatik am Nachmittag nach Einschätzung der Lehrer und Eltern. An dieser Stelle soll insbesondere auf Effekte im Urteil der Eltern eingegangen werden. Methode: In einer placebo-kontrollierten, randomisierten, doppelblinden, multizentrischen Studie wurden 85 durchschnittlich intelligente Kinder (Alter 6-16 Jahre, Diagnose: ADHS) untersucht. Die Dauer der Behandlung mit Medikinet®-Retard (n = 43) bzw. Placebo (n = 42) betrug 4 Wochen mit wöchentlichen Visiten. Eine wöchentliche Titrierung erfolgte bis maximal 60 mg in Abhängigkeit vom Körpergewicht und dem Verlauf der Symptomatik. Kriterium für die Verminderung der Symptomatik in der Familie war die wöchentliche Einschätzung der Lehrer und Eltern im Fremdbeurteilungsbogen für Hyperkinetische Störungen (FBB-HKS). Ergebnisse: In der ADHS-Symptomatik, erfasst über den FBB-HKS, ließen sich signifikante Medikamentenwirkungen nachweisen. Die Effektstärke der Veränderungen lag bei d = 1.2 (Gesamtkennwert). Die Effekte ließen sich für Aufmerksamkeitsstörung, Hyperaktivität und Impulsivität auf den entsprechenden Subskalen belegen. Die Wirksamkeit von Medikinet®-Retard wurde von den Eltern durchschnittlich als gut eingeschätzt. Die Reponderrate war in der Verumgruppe viermal höher. Die Korrelationen der Veränderungswerte im Elternurteil mit den Veränderungswerten im Lehrerurteil lagen im mittleren Bereich. Schlussfolgerung: Mit dieser Studie liegen im deutschsprachigen Raum erstmals Daten für eine erfolgreiche Symptomreduktion und gute Wirksamkeit im Elternurteil eines langzeitwirksamen Methylphenidatpräparates (Medikinet®-Retard) vor. Die zweistufige Freisetzungsdynamik erlaubt eine praxistaugliche morgendliche Einmalgabe. Es zeigen sich Wirkungen bis in den Nachmittag.
Therapie der Tic-Störungen
Authors: Roessner Veit , Banaschewski Tobias , Rothenberger Aribert
Published: November 2004

Zusammenfassung: Hintergrund: In den letzen zehn Jahren wurde in zahlreichen Studien über die Therapie der Tic-Störungen berichtet. Die Einführung neuartiger Neuroleptika sowie die immer weiter entwickelten Techniken der Verhaltenstherapie geben den von einer Tic-Störung betroffenen Kindern und Jugendlichen neue Hoffnung. Fragestellung: Um die neuen Standards in der Therapie kennen zu lernen, ist es notwendig, sich kritisch mit der Qualität dieser Studien zu befassen. Methode: Eine kritische Übersicht der evidenzbasierten Literatur und praktischer Erfahrungen. Ergebnisse: Weltweit existiert hinsichtlich der Pharmakotherapie der fundierteste klinische Kenntnisstand zu Clonidin und (aus der Gruppe der neuen Antipsychotika) zu Risperidon, während in Europa die Benzamide seit Jahrzehnten sehr erfolgreich angewendet werden. Zu verhaltenstherapeutischen Verfahren finden sich zunehmend empirische und hilfreiche Daten. Schlussfolgerung: Risperidon könnte das Medikament der ersten Wahl bei der Behandlung der Tic-Störungen werden. Verhaltenstherapeutische Verfahren scheinen immer häufiger in multimodalen Therapiekonzepten angewendet zu werden.
Granular mass flows and Coulomb's friction in shear cell experiments: Implications for geophysical flows
Authors: Cagnoli B. , Manga M.
Published: November 2004

Granular mass flows of rock fragments are studied in the lab by means of a high‐speed video camera at 2000 frames per second. These granular flows are generated using beds of pumice fragments positioned on a rough rotating disk, whose angular velocity is controlled by a motor. The experimental apparatus allows an understanding of the arrangement of the particles in granular mass flows with relatively small and relatively large values of the Savage number (the Savage number represents the ratio between grain collision stresses and gravitational grain contact stresses). In particular, these flows develop a basal layer of agitated and colliding particles underneath a relatively rigid upper layer. Our experimental results suggest the validity, on average, of the Coulomb's relationship between shear and normal forces at the base of granular mass flows irrespective of their Savage number value. In Coulomb's equation the shear stresses do not depend on the shear rate. We expect the Coulomb friction law to be valid also in moving pyroclastic flows. Our experiments suggest that the collisions and subsequent comminution of pumice fragments in moving pyroclastic flows could provide ash for the overriding ash clouds. In our experiments the amount of ash generated by particle‐particle and particle‐boundary interactions increases as the value of the Savage number increases. In nature, part of this ash may also simply move toward the base of the flows because of kinetic sieving.
Immune cell function testing: an adjunct to therapeutic drug monitoring in transplant patient management
Authors: Kowalski Richard , Post Diane , Schneider Mary C , Britz Judith , Thomas Judy , Deierhoi Mark , Lobashevsky Andrew , Redfield Robert , Schweitzer Eugene , Heredia Alonso , Reardon Elise , Davis Charles , Bentlejewski Carol , Fung John , Shapiro Ron , Zeevi Adriana
Published: November 2004

Abstract:  Each year, 55 000 organ transplants are performed worldwide. Cumulatively, the number of living organ recipients is now estimated to be over 300 000. Most of these transplant recipients will remain on immunosuppressive drugs for the remainder of their lives to prevent rejection episodes. Controlled doses of these drugs are required to prevent over‐medication, which may leave the patient susceptible to opportunistic infection and drug toxicity effects, or under‐dosing, which may lead to shortened graft survival because of rejection episodes.

This paper describes the result of a multicenter study conducted at the Universities of Pittsburgh, Alabama and Maryland to evaluate an in vitro assay (CylexTM Immune Cell Function Assay) for the measurement of global immune response in transplant patients receiving immunosuppressive therapy. The assay uses a whole blood sample to maintain the presence of the drug during incubation. Following overnight incubation of blood with phytohemagglutinin (PHA), CD4 cells are selected using paramagnetic particles coated with a monoclonal antibody to the CD4 epitope. The CD4‐positive cells are targeted as major immunosuppressive drugs are designed to specifically inhibit T‐cell activation which has been implicated in rejection.

The data generated at these three sites were submitted in support of an Food and Drug Association (FDA) application for the use of this assay in the detection of cell‐mediated immunity in an immunosuppressed population. The assay was cleared by the FDA on April 2, 2002. This cross‐sectional study was designed to establish ranges for reactivity of this bioassay in the assessment of functional immunity for an individual solid organ recipient at any point in time.
Emergency living related liver transplantation for fulminant reactivation of hepatitis B virus after unrelated marrow transplantation
Authors: Au WY , Lau GKK , Lie AKW , Liang R , Lo CM , Fan ST , Liu CL , Hawkins BR , Ng IOL , Kwong YL
Published: November 2004

Abstract: We report a unique case of emergency living related donor orthotopic liver transplantation (OLT) for late fulminant reactivation of hepatitis B virus (HBV) after matched unrelated bone marrow transplantation (BMT) for chronic myeloid leukemia (CML). Cessation of lamivudine after BMT for HBV positive patients may carry risks of late fatal HBV reactivation. Similar to fulminant HBV reactivation in the general population, OLT under resumption of lamivudine can be life saving. In our case, concomitantly molecular relapse of CML at the time of liver failure was also cleared by OLT, possibly via a ‘liver‐graft vs. leukemia’ effect. Liver rejection (graft vs. graft disease) was mild due to inherent immunocompromise of the marrow graft. Hence BMT recipients in stable remission should not be denied the opportunity for life‐saving solid organ transplantation. A choice of marrow and liver donors with innate HBV immunity may be needed to give the additional advantage of long‐term HBV clearance.
BK virus infection in renal transplant recipients
Authors: Lin P. Ling , Vats Abhay N. , Green Michael
Published: November 2004

Abstract: BK virus (BKV) is increasingly being recognized as an important pathogen among renal transplant recipients. To date, only limited information is known about BKV infections in this population; definitive data regarding the epidemiology, diagnosis, treatment, and outcome of BKV infection are lacking. Therefore, further investigations are needed. This article reviews our current understanding of BKV infections among renal transplant patients.
Genetic differentiation among populations of a migratory songbird: Limnothlypis swainsonii
Authors: Winker Kevin , Graves Gary R. , Braun Michael J.
Published: November 2004

Population structure and gene flow were inferred from isozyme variation at 26 loci among five populations of Limnothlypis
swainsonii (Swainson's Warbler; Parulidae), a Nearctic‐Neotropic
migrant songbird breeding in the unglaciated southeastern U.S.A. These
populations exhibit relatively high levels of heterozygosity (

image

=0.083), and 16 of 26 loci were polymorphic in at least one population
(

image

=0.385). Allelic frequencies were significantly heterogeneous at five
loci, indicating a surprising degree of population structure for a
migratory bird with no recognized subspecies (FST
=0.043). Moderate levels of gene flow are inferred (Nm=1.5 to 11.7), yet population structure does not fit an isolation‐by‐distance model. Genetic heterogeneity is mostly due to differentiation between an Arkansas population and four populations from the coastal plain (from Louisiana to Virginia). Genetic drift may be responsible for much of the observed structure, but the lack of obvious barriers to dispersal between Arkansas and the coastal plain suggests that differentiation has been maintained by some other mechanism(s). Vicariance events on the breeding range, a split wintering range, or both could contribute to the pattern of differentiation observed.
Chick growth in albatrosses: curve fitting with a twist
Authors: Huin N. , Prince (deceased) P. A.
Published: November 2004

We present a new type of equation to describe the growth patterns of procellariiform seabirds and other species whose chicks characteristically lose mass towards the end of the rearing period. Our equation is based on the Gompertz curve; our principles are also applicable to logistic and von Bertalanffy curves. From our model, five coefficients can be derived to characterise the patterns of growth. These are: growth rate, peak mass and age at which it is attained, loss rate and an index describing the overall shape of the curve. We illustrate the use of this new equation with data collected, using automated weighing platforms, on six years of chick growth of Black‐browed Diomedea
melanophris and Grey‐headed D. chrysostoma albatrosses at Bird Island, South Georgia. In comparison with Grey‐headed Albatross, Black‐browed Albatross chicks grow at a faster rate and to a higher peak mass; they also reach their peak mass at an earlier age, and lose mass at a faster rate in the mass recession period. However, in both species, chicks reached peak mass when 72% of the rearing period had elapsed; within species, only this did not vary between years. This new equation not only enables the period of mass recession to be incorporated into growth analysis, but, because it does not require assumptions about asymptotic mass, greatly facilitates inter‐species comparisons.
Three‐dimensional assessment of treatment outcomes on the face
Authors: Moss JP , Ismail SFH , Hennessy RJ
Published: November 2004

Structured Abstract

Authors– Moss JP, Ismail SFH, Hennessy RJ

Objectives – To investigate the effect on the face of treatment involving extractions.

Design – A prospective study of the effects of extraction and non‐extraction treatment on two groups of patients was undertaken.

Setting and sample population – Initially there were 16 non‐extraction and 18 extraction patients but at the end of treatment there were only 12 in each group.

Experimental variable – Each of the patients was scanned using a three‐dimensional (3‐D) MGI scanner and the 3‐D scans were analysed using registration and surface shape analysis programs. The registration program registers the scans over the forehead and then shows the differences in colour between the two scans. The surface shape analysis mathematically differentiates the surface into nine different surface shapes.

Results – The results indicated that there was a difference between the two groups at the start of treatment but there were no differences in the effect on the face of treatment in the two groups. The surface morphology was similar at the end of treatment in both groups.

Conclusion – It was concluded that in this preliminary study that whether treatment is undertaken with or without extractions, in this group of patients the facial morphology was not significantly different.
Micro X‐ray computed tomography analysis for the evaluation of asymmetrical condylar growth in the rat
Authors: Nakano H , Watahiki J , Kubota M , Maki K , Shibasaki Y , Hatcher D , Miller AJ
Published: November 2004

Structured Abstract

Authors– Nakano H, Watahiki J, Kubota M, Maki K, Shibasaki Y, Hatcher D, Miller AJ

Objectives –
To investigate the influence of forced lateral bite on mandibular growth, micro X‐ray computed tomography (CT) was used for the purpose evaluating condylar cartilage and cancellous bone formation in 10 male Wister rats (3 weeks of age).

Settings and sample population –
The rats were divided into two groups – experimental and control. In experimental group, an inclined crown was cemented onto the maxillary incisors to produce 2.5 mm shift toward the left side during mastication. Right–left differences in whole mandibular length, mandibular height, condylar size, trabecular structure of the condylar head and three‐dimensional (3‐D) finite element analysis were assessed using 3‐D images reconstructed from micro X‐ray CT scans when the mice had reached 21 weeks.

Measurements and Results –
Asymmetrical growth was found in the experimental group, in which the left condylar head became thicker and shorter than the right condylar head during development. When comparing the left and right condyles of the experimental animals, histomorphometric analysis from micro X‐ray CT showed that the bone volume (BV) of the cancellous bone, the surface area of the cancellous bone (BS), the BS/BV ratio, the BV fraction (BV/TV), and the trabecular thickness and trabecular number were less for the right condyle than for the left condyle.

Conclusions –
These findings suggested that artificial changes in the mastication do influence the growth of condylar head, condylar bone trabecular structure, and mineralization.
Computer simulation system for orthognathic surgery
Authors: Noguchi N , Goto M
Published: November 2004

Structured Abstract

Authors– Noguchi N, Goto M

Objective – The system aimed to make a simulation model of an orthognathic patient without using his/her computed tomography data.

Design – The morphological data of the teeth and face were obtained by laser scanner. All the data were integrated in the reference coordinate system of frontal and lateral cephalograms using projection matching technique.

Setting – A case of mandibular prognathism was analyzed and presented.

Experimental variable – About 7 mm (left side) to 6 mm (right side) of mandibular setback with a small rotation was performed on this case.

Results – Simulated osteotomies and bone movements help us to analyze the movement of bone and soft tissue. Collisions and gaps generated between bone segments and facial changes are shown.

Conclusion – This simulation system will be particularly useful for the selection of an optimal operative method in cases in which the change in facial soft tissue shape should be carefully deliberated.
Prolonged cholestasis and ductopenia following gold salt therapy
Authors: Basset Céline , Vadrot Jacqueline , Denis Jacques , Poupon Joël , Zafrani Elie Serge
Published: November 2004

Abstract: Hepatotoxicity, predominantly cholestatic, is a rare adverse effect of gold salt therapy, which usually completely resolves within a few months. We report the case of a female patient treated for rheumatoid arthritis, who had gold salt overdose, and in whom acute cholestatic hepatitis occurred three weeks after beginning of therapy. Evolution of gold concentration was followed in plasma and urine, as well as in cutaneous and liver dry tissue. Liver biopsy showed marked inflammatory changes of interlobular bile ducts that evolved towards ductopenia, which was responsible for prolonged cholestasis still present 15 months later. In addition, sialadenitis with sicca syndrome was noted six months after onset of the disease. The mechanism of hepatotoxicity was probably immunoallergic since liver lesions were associated with hypersensitivity syndrome including dermatitis and blood and tissue eosinophilia. This is the first report of gold salt hepatotoxicity with histological demonstration of cholangitis followed by ductopenia.
The effect of patch isolation on reproductive synchrony in the root vole
Authors: Johannesen Edda , Andreassen Harry P. , Ims Rolf A.
Published: November 2004

Both social and environmental cues can synchronise breeding, but are likely to operate at different spatial and temporal scales. Here we test if breeding is synchronised at the patch or the population level in experimental patchy populations of root voles. We found no overall synchronisation neither at the patch nor at the population level. However, at the patch level, breeding was synchronised within patches if the patches were isolated and thus had little exchange of animals with other patches. In accordance with what has been predicted for matrilineally structured populations, we conclude that breeding synchrony is facilitated when social cues are exchanged within stable female groups.
Crowding‐induced plasticity in Epirrita autumnata (Lepidoptera: Geometridae): weak evidence of specific modifications in reaction norms
Authors: Tammaru Toomas , Ruohomäki Kai , Montola Mika
Published: November 2004

We sought to distinguish between two potential effects of larval crowding on developmental schedules in Epirrita autumnata, an
outbreaking folivorous moth. We asked if consequences of crowding can be
entirely attributed to deterioration of environment, caused by mutual
disturbance of larvae, or if there are specific modifications of reaction
norms involved. In a laboratory rearing experiment, we found that most of
the consequences of larval crowding could be explained as unspecific
environmental effects. However, there was some evidence of
crowding‐related modifications of reaction norms. In particular, crowding
during early development more strongly affected further growth of larvae
than expected from the direct influence of inferior environmental
quality: larvae crowded early in development had shorter growth periods
in the final instar and attained lower final weights. It is not clear if
these modifications of reaction norms are adaptive. Nevertheless, these
observations document a type of plasticity which is different from
unidimensional responses to variation in environmental quality, and may
thus contribute to understanding evolution of body size in insects.
However, recorded modifications of reaction norms are apparently weak
enough to have only a minor role in population dynamics of E.
autumnata.
A general model for selection among modules in haplo‐diploid life histories
Authors: Poore Alistair G. B. , Fagerström Torbjörn
Published: November 2004

Genetic variation resulting from changes during somatic development in modular organisms may be inherited by subsequent generations due to the late development of their germ line. As a consequence, both sexually and asexually produced offspring may be genetically variable. The presence of heritable intraclonal variation and the great life history variation among modular organisms requires that evolutionary theory does not limit selection to only that occurring among individuals resulting from meiosis and zygote formation. To allow for variation within clonal lineages, and encompass a wide variety of life histories, we construct a simple model of selection among modules in life histories that contain both haploid and diploid phases, such as that seen among many multicellular algae. Selection among modules is a demographic process with module performance depending on its genotype at a single locus with two alleles. The model is used to simulate the spread of a beneficial allele in life histories that vary in the relative amount of sexual and asexual reproduction. The time taken for allele fixation is shown to depend on both demographic and genetic factors.
Identifying the density‐dependent structure underlying ecological time series
Authors: Berryman Alan , Turchin Peter
Published: November 2004

A central problem in ecology is explaining the causes of population fluctuations, and an important step in the solution is determining the structure of the negative feedback (density dependent) process regulating population dynamics. The conventional way to determine the dimension or order of density dependence in a time series is to calculate the partial autorcorrelation function (PACF). We maintain, however, that PACF is not designed with biological populations in mind and has the wrong null model for detecting the structure of density dependence. We suggest an alternative diagnostic, the partial rate correlation function (PRCF), which is specifically designed for biological populations and has an appropriate null model for detecting their density dependent structures. Tests with simulated data show PRCF to be superior to PACF in detecting the underlying density dependent structure of two simple mathematical models.
Effects of epiphytic lichens on host preference of the vascular epiphyte Tillandsia usneoides
Authors: Callaway Ragan M. , Reinhart Kurt O. , Tucker Shirley C. , Pennings Steven C.
Published: November 2004

We investigated the potential for nonvascular epiphytic species (primarily lichens) to affect the quality of different host tree species for the vascular epiphyte Tillandsia usneoides in the southeastern USA. Different host tree species had substantially different abundances of Tillandsia, and these abundances were correlated with the composition of nonvascular epiphyte communities. In greenhouse experiments Tillandsia grew significantly faster on the branches of Quercus virginiana (a species with very high natural abundances of Tillandsia) when the dominant lichen on Q. virginiana was left intact than when the lichen was removed from the branches. In laboratory experiments, extracts from Cryptothecia rubrocincta, a lichen that was 10 times more common on poor host species for Tillandsia than on good host species, reduced Tillandsia seedling survival and growth in comparison to extracts from other species and rainwater. In field experiments, lichens increased the proportion of Tillandsia seeds and vegetative strands that adhered to the trunk of Ilex opaca (a poor Tillandsia host), but lichens did not affect propagule adherence to Q. virginiana. Our results are by no means exhaustive of the possibilities, but they suggest that the structure and diversity of vascular and nonvascular epiphytic communities that grow in different tree species may not be simply the product of host tree characteristics, but may also be influenced by interactions among the epiphytes themselves.
Metabolism of Salbutamol Differs between Asthmatic Patients and Healthy Volunteers
Authors: Sjöswärd Kerstin Naidu , Josefsson Martin , Ahlner Johan , Andersson Rolf G.G. , Schmekel Birgitta
Published: November 2004

Abstract: Patients with asthma are a target group for medication with β2‐agonists, often in combination with corticosteroids. Salbutamol is commonly marketed as racemate. R‐Salbutamol carries β2‐agonistic property whereas S‐salbutamol does not. The racemate undergoes stereoselective sulphatisation by sulfotransferases mainly in the gut and liver, so that S‐salbutamol rests for a longer time in the body and reaches higher plasma levels than R‐salbutamol. Ten patients with mild stable asthma and at present without cortisone medication were given racemic salbutamol as ventoline 4 mg orally. Plasma and urine levels were estimated until 24 hr after ingestion. For comparison healthy volunteers were treated in the same way.The group of asthma patients was then treated with budesonide inhalations 800 μg daily for one week and the initial programme resumed. Non‐cortisone‐treated asthmatic patients displayed higher levels of both R‐ and S‐salbutamol in plasma than did healthy volunteers after one single ingestion of racemic salbutamol (CMAX both comparisons P<0.05). Plasma levels of salbutamol isomers in cortisone‐treated asthmatic patients resembled the levels in volunteers. The most plausible explanation for the discrepancy in values between asthmatic patients and volunteers is a defective metabolic function by asthmatic patients possibly enzymatic in origin.
Exploratory multivariate spectroscopic study on human skin
Authors: Lauridsen Rikke Kragh , Everland Hanne , Nielsen Lene Feldskov , Engelsen Søren Balling , Nørgaard Lars
Published: November 2004

Background/aims: Spectroscopy on human skin is a field that is being adopted increasingly because of its rapidity and high reproducibility. Infrared reflectance (IR), near‐infrared reflectance (NIR), and fluorescence spectroscopy have previously been applied to human skin in vivo to compare healthy and sick skin, including skin cancer, atopy, and leprosy. Exploratory data analysis/chemometrics is a tool for evaluating multivariate data such as spectroscopic measurements. The objective of this study was to explore the spectral variance spanned by people with normal integument, and to demonstrate the advantages of multivariate analysis to skin research.

Methods: IR, NIR and fluorescence spectroscopy have been carried out in vivo on 216 volunteers' forearms before and after four tape strippings. The subjects were asked to fill in a questionnaire regarding factors suspected to influence the measurement results. Principal Component Analysis (PCA) was used to investigate whether the population can be divided into groups on the basis of their skin chemistry. Unless otherwise stated, the results are from the measurements prior to stripping.

Results: In contrast to IR and fluorescence spectra, NIR spectra proved able to detect gender differences. By use of PCA, classifications on male and female subjects were observed from the IR and NIR measurements, and as an indication from the fluorescence measurements. The NIR and fluorescence measurements varied between elderly and young subjects. The largest variance in the fluorescence landscapes was seen between pigmented and non‐pigmented skin. No connection was found between the spectroscopic measurements and smoking or drinking habits.

Conclusions: Future spectroscopic skin investigations should be balanced as regards to gender and age, as these can possibly affect the measurement results. Chemometrics proved to be superior to traditional attempts of interpreting the spectra.
The use of fluoride varnishes in the prevention of dental caries: a short review
Authors: Strohmenger L , Brambilla E
Published: November 2004

OBJECTIVES: To review the current literature regarding the anti‐caries efficacy of fluoride varnishes. To analyse a series of studies designed to detect the caries preventive efficacy of fluoride varnishes by means of meta‐analysis.

MATERIALS AND METHODS: Current literature on fluoride varnishes has been reviewed. An evaluation of the results of the available in vitro, animal and human studies on the anti‐caries efficacy of these preventive agents was performed. A systematic literature search and a meta‐analysis were also performed to assess the caries preventive effects of fluoride varnishes. The purpose of this analysis was to calculate the overall preventive efficacy of clinical fluoride varnishes treatment studies, based on defined methodological criteria.

RESULTS: The efficacy of fluoride varnishes in caries prevention is clearly demonstrated in several experimental studies. Clinical trials show caries incidence reduction ranging approximately from 18% to 70%. Nevertheless, available studies show a high degree of heterogeneity and only three were found to meet a series of defined methodological criteria. All the three studies were based on a comparison between 0.2% NaF rinses and a fluoride varnish. The meta‐analysis showed no significant differences between the two treatments.

CONCLUSIONS: Available data suggest that fluoride varnishes are a useful tool in caries prevention. One may conclude that fluoride varnishes, when applied regularly, demonstrate good caries preventive properties.
Parotid salivary basic proline‐rich proteins inhibit HIV‐1 infectivity
Authors: Robinovitch MR , Ashley RL , Iversen JM , Vigoren EM , Oppenheim FG , Lamkin M
Published: November 2004

OBJECTIVE: The objective of this study was to investigate the molecular nature, spectrum of activity and mechanism(s) of action of those human parotid basic proline‐rich proteins that exhibit anti‐HIV‐1 activity.

DESIGN: Fractions containing the basic proline‐rich proteins were obtained from human parotid saliva of presumed HIV‐1 non‐infected human subjects and characterized with respect to their purity, apparent molecular size and their ability to inhibit the infectivity of T‐tropic and M‐tropic strains of HIV‐1.

SUBJECTS, MATERIALS AND METHODS: Stimulated parotid saliva samples were collected from human subjects who denied having any risk factors for HIV‐1 infection and whose parotid salivas inhibited HIV‐1 infectivity. Such samples were subjected to affinity, molecular sieve and ion exchange chromatography to isolate individual salivary components. Those fractions demonstrating anti‐HIV‐1 activity were analyzed by SDS‐PAGE in order to assess their purity and determine their apparent molecular weights. HIV‐1 inhibitory activity was determined using HIV‐1 strains LAI and BaL in a Hela cell‐derived multinuclear activation of a galactosidase indicator (MAGI) assay. Amino acid analyses were performed on some fractions.

RESULTS: Recombinant gp120‐CH‐Sepharose chromatography of one subject's parotid saliva revealed specific binding of human parotid basic proline‐rich proteins, most prominently one with an apparent molecular weight of 37 kDa. Molecular sieve and cation exchange chromatography yielded a fraction greatly enriched in this protein which amino acid analysis confirmed was proline‐rich. A similar fraction from two other subjects also contained basic proline‐rich proteins of similar molecular size. These fractions inhibited both T‐tropic and M‐tropic strains of HIV‐1 when assayed in the MAGI system. Since SLPI activity is not observable in the MAGI assay, this inhibition was not due to SLPI. The presence of thrombospondin‐1 (TSP‐1) in the active fractions was precluded on the basis of SDS‐PAGE examination.

CONCLUSIONS: Specific basic proline‐rich proteins in human parotid saliva possess significant anti‐HIV‐1 activity independent of that attributable to SLPI or TSP‐1. Since the inhibition is detectable with the MAGI assay, its mechanism of action involves virus‐host cell interaction prior to the introduction of the tat gene product into the host cell and may be through the binding of the basic proline‐rich proteins to the HIV‐1 gp120 coat of the virus.
The impact of chlorhexidine gluconate on the relative cell surface hydrophobicity of oral Candida albicans
Authors: Anil S , Ellepola ANB , Samaranayake1 LP
Published: November 2004

OBJECTIVES: Adherence of Candida albicans has been implicated as the first step in the pathogenesis of oral candidosis, and its relative cell surface hydrophobicity (CSH) a contributory physical force. Chlorhexidine gluconate is by far the commonest antiseptic mouthwash prescribed in dentistry. The intra‐oral concentrations of the retained chlorhexidine mouthwash fluctuate considerably due to the dilution effect of saliva and the cleansing action of the oral musculature. Hence the objective of the present study was to investigate the effect of brief exposure to sub‐therapeutic concentrations of chlorhexidine gluconate on the relative CSH of C. albicans.

DESIGN: The CSH of the isolates was assessed by a biphasic aqueous‐hydrocarbon assay.

RESULTS: A statistically significant reduction in CSH was observed following the exposure of Candida isolates to 0.005 and 0.0025% chlorhexidine gluconate.

CONCLUSIONS: These results elucidate additional mechanisms by which chlorhexidine gluconate suppress candidal pathogenicity despite a brief period of transient exposure within the oral environment.
Oral metastasis of telangiectatic osteosarcoma
Authors: Alves FA , Lopes MA , Ikeda MK , Kowalski LP , Almeida OP
Published: November 2004

Metastases of osteosarcoma in the mouth are rare, and only few cases have been described. We present a case of telangiectatic osteosarcoma of the femur in a 15‐year‐old girl, who developed metastases in the humerus, lungs and retromolar area 4 years after initial diagnosis and treatment. The girl died 2 months after the diagnosis of metastases despite treatment with chemotherapy. This report emphasizes that telangiectatic osteosarcoma has a very poor prognosis, particularly when multiple metastases develop.
Formation and properties of halogenated aluminum clusters
Authors: Bergeron D. E. , Castleman A. W. , Morisato T. , Khanna S. N.
Published: November 2004

The fast-flow tube reaction apparatus was employed to study the halogenation of aluminum clusters. For reactions with HX (X=Cl, Br, and I), acid-etching pathways are evident, and we present findings for several reactions, whereby AlnX− generation is energetically favorable. Tandem reaction experiments allowed us to establish that for AlnCl−, AlnI−, and AlnI2−, species with n=6, 7, and 15 are particularly resistant to attack by oxygen. Further, trends in reactivity suggest that, in general, iodine incorporation leaves the aluminum clusters’ electronic properties largely unperturbed. Ab initio calculations were performed to better interpret reaction mechanisms and elucidate the characteristics of the products. Lowest energy structures for Al13X− were found to feature icosahedral Al13 units with the halogen atom located at the on-top site. The charge density of the highest occupied molecular orbital in these clusters is heavily dependent on the identity of X. The dependence of reactivity on the clusters’ charge state is also discussed. In addition, we address the enhanced stability of Al13I− and Al13I2−, arguing that the superhalogen behavior of Al13 in these clusters can provide unique opportunities for the synthesis of novel materials with saltlike structures.
Thermodynamic properties of Lennard-Jones chain molecules: Renormalization-group corrections to a modified statistical associating fluid theory
Authors: Llovell Fèlix , Pàmies Josep C. , Vega Lourdes F.
Published: November 2004

A modified version of the statistical associating fluid theory (SAFT), the so-called soft-SAFT equation of state (EOS), has been extended by a crossover treatment to take into account the long density fluctuations encountered when the critical region is approached. The procedure, based on White’s work from the renormalization group theory [Fluid Phase Equilibria 75, 53 (1992); L. W. Salvino and J. A. White, J. Chem. Phys. 96, 4559 (1992)], is implemented in terms of recursion relations where the density fluctuations are successively incorporated. The crossover soft-SAFT equation provides the correct nonclassical critical exponents when approaching the critical point, and reduces to the original soft-SAFT equation far from the critical region. The accuracy of the global equation is tested by direct comparison with molecular simulation results of Lennard-Jones chains, obtaining very good agreement and clear improvements compared to the original soft-SAFT EOS. Excellent agreement with vapor-liquid equilibrium experimental data inside and outside the critical region for the n-alkane series is also obtained. We provide a set of transferable molecular parameters for this family, unique for the whole range of thermodynamic properties.
The nature of the complex formed between pyridine and hydrogen bromide in the gas phase: An experimental approach using rotational spectroscopy
Authors: Cole G. C. , Legon A. C.
Published: November 2004

The rotational spectra of two isotopomers, C5H5N⋯H79Br and C5H5N⋯H81Br, of a complex formed by pyridine and hydrogen bromide were observed by using a pulsed-jet, Fourier-transform microwave spectrometer that incorporated a mixing nozzle. Rotational constants, centrifugal distortion constants, and nuclear quadrupole coupling constants for the N14 and Br nuclei were determined. The rotational constants indicate that the observed complex has a planar geometry of C2v symmetry, with the HBr subunit lying along the C2 axis of pyridine. These conclusions are in good agreement with those obtained earlier from infrared spectroscopy in cryogenic matrices and ab initio calculations. The distance r(N⋯H)=1.137(2) Å was obtained by fitting the rotational constants under the assumption of an unchanged pyridine geometry and with r(H–Br) fixed at the value obtained through an ab initio calculation. The nuclear quadrupole coupling constants were interpreted, with the aid of ab initio calculations for the complex, as well as hydrogen-bonded and ion-pair limiting models for the interaction of pyridine and HBr, to establish that the complex may be visualized in terms of a substantial contribution (>60%) of the ionic structure C5H5NH+⋯Br− to its valence-bond description. The intermolecular force constant kσ=57.8(16) N m−1 determined from the centrifugal distortion constants ΔJ of the two isotopomers is also consistent with a strongly bound complex involving partial proton transfer.
Phase evolution of lamellar cationic lipid-DNA complex: Steric effect of an electrolyte
Authors: González-Amezcua O. , Hernández-Contreras M.
Published: November 2004

The complexation isotherms of DNA plus lipids of a symmetric lamellar cationic lipid-DNA system were determined within a mean field free energy. The free energy incorporates the ion’s finite size of NaCl simple electrolyte in solution and makes use of known structure data on this complex. The results for the predicted isotherms are in qualitative agreement with the trends of the experimental data for this property.
Electrical and optical properties of rod-like defects in silicon
Authors: Goss J. P. , Briddon P. R. , Eberlein T. A. G. , Jones R. , Pinho N. , Blumenau A. T. , Öberg S.
Published: November 2004

Self-interstitials in silicon can aggregate to form rod-like defects (RLDs) having both electrical and optical activity. We carry out local density functional calculations for both {113} and {111} RLDs to determine their structures and electrical activity. We find that small {113} RLDs are more stable than {111} RLDs but this reverses for larger defects. We attribute the electrical activity of {113} RLDs found in deep level transient spectroscopy studies with the bounding dislocations and the 0.903 eV photoluminescence to vacancy point defects lying on the habit plane.
Transient electrophosphorescence in red top-emitting organic light-emitting devices
Authors: Moon D. G. , Pode R. B. , Lee C. J. , Han J. I.
Published: November 2004

We have fabricated a red electrophosphorescent top-emitting organic light-emitting device using the phosphorescent bis[2-(2′-benzothienyl)-pyridinato-N,C3′]iridium(acetylacetonate) doped in 4,4′-N,N′-dicarbazole-biphenyl host and Alq3 electron injection layer. The emission spectrum shows a strong peak at 620nm accompanied with a small peak at 675nm in the red region. Time evolution of electrophosphorescence reveals a decay time of 703μs at a voltage pulse of 5V in a device with an emitting area of 20mm2. Rise and delay times vary from 450to14μs and 73to3μs, respectively, as the voltage amplitude increases from 4.5to10V. These results are compared with the red emitting device without an electron injection layer.
Simplified Besocke scanning tunneling microscope with linear approach geometry
Authors: Ball S. J. , Contant G. E. , McLean A. B.
Published: November 2004

Besocke-style scanning tunneling microscopes are used in low and variable temperature applications because they are compact and the tip-sample spacing is insensitive to thermal drift. It is demonstrated that the economical Besocke design can be simplified even further if a linear approach geometry is used. In this geometry, the sample has only to be moved along two orthogonal axes and just 11 wires are required to control both tip-sample approach and image acquisition. This simplifies the control electronics, increases the reliability of the microscope and, if the microscope is operated in a cryostat, it weakens the thermal link between low and room temperature. Nevertheless, all of the advantages of the Besocke design are retained including thermal compensation of the tip-sample spacing. A self-aligning mechanism is also described that automatically locates the sample relative to the scanner before tip-sample approach. This feature is particularly useful because the microscope is designed for remote operation in a cryostat where there is restricted visual access. Graphite was used as a test surface and images are presented of β-site corrugation and moiré supermeshes.
Room-temperature, mid-infrared (λ=4.7μm) electroluminescence from single-stage intersubband GaAs-based edge emitters
Authors: Xu D. P. , Mirabedini A. , D’Souza M. , Li S. , Botez D. , Lyakh A. , Shen Y-J. , Zory P. , Gmachl C.
Published: November 2004

GaAs -based, single-stage, intersubband devices with active regions composed of deep quantum wells (i.e., In0.3Ga0.7As) and high AlGaAs barriers display strong room-temperature emission at λ=4.7μm. The structures are grown by metalorganic chemical vapor deposition. The large energy barriers (∼360meV) for electrons in the upper energy level of the active region strongly suppress both the carrier leakage as well as the tunneling escape rate out of the wells. As a result, the ratio of emissions at 80 and 300K is as low as 2.0, and thus there is considerably less need for a Bragg mirror/transmitter-type region. Devices with virtually 100% tunneling injection efficiency have been realized, and their room-temperature spectra are narrow: 25meV full width at half maximum. These deep-well, single-stage structures are intended for use as the emitting units in two-dimensional, intersubband quantum-box lasers, or as the stages of quantum-cascade lasers for efficient, room-temperature operation in the 3–5-μm wavelength range.
Stress/strain dependence of ac loss and critical current of Bi2Sr2Ca2Cu3O10 reinforced tape
Authors: Zhang Guo Min , Schwartz Justin , Sastry P. V. P. S. S. , Lin Liang Zhen , Xiao Li Ye , Yu Yun Jia
Published: November 2004

The critical current and ac loss of a stainless steel reinforced Bi2Sr2Ca2Cu3O10 composite superconducting tape were measured under tensile stress/strain at 77K. By use of the definition of irreversible strain, a formula describing the variation of the critical current with strain was proposed. A relationship between ac loss and tensile strain was developed from Norris’ formula and the critical current–strain relation. It is shown that the experimental results agree well with the values calculated from our formulas.