bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of the Random Forest Method to Analyse Epidemiological and Phenotypic Characteristics of Salmonella 4,[5],12:i:‐ and Salmonella Typhimurium Strains
Authors: Barco L. , Mancin M. , Ruffa M. , Saccardin C. , Minorello C. , Zavagnin P. , Lettini A.A , Olsen J. E. , Ricci A. 
Published: May 2012

SummarySalmonella enterica 4,[5],12:i:‐ is a monophasic variant of S. Typhimurium. In the last decade, its prevalence rose sharply. Although S. 4,[5],12:i:‐ and S. Typhimurium are known to pose a considerable public health risk, there is no detailed information on the circulation of these serovars in Italy, particularly as far as veterinary isolates are concerned. For this reason, a data set of 877 strains isolated in the north‐east of Italy from foodstuffs, animals and environment was analysed during 2005–2010. The Random Forests (RF) method was used to identify the most important epidemiological and phenotypic variables to show the difference between the two serovars. Both descriptive analysis and RF revealed that S. 4,[5],12:i:‐ is less heterogeneous than S. Typhimurium. RF highlighted that phage type was the most important variable to differentiate the two serovars. The most common phage types identified for S. 4,[5],12:i:‐ were DT20a, U311 and DT193. The same phage types were also found in S. Typhimurium isolates, although with a much lower prevalence. DT7 and DT120 were ascribed to the two serovars at comparable levels. DT104, DT2 and DT99 were ascribed exclusively to S. Typhimurium, and almost all the other phage types identified were more related to the latter serovar. Such data confirm that phage typing can provide an indication of the biphasic or monophasic state of the strains investigated and could therefore support serotyping results. However, phage typing cannot be used as the definitive method to differentiate the two serovars, as part of the phage types were detected for both serovars and, in particular, all phage types found for S. 4,[5],12:i‐ were found also for S. Typhimurium.
A review of equine sarcoid
Authors: Taylor S. , Haldorson G. 
Published: May 2012

SummaryEquine sarcoid is the most common tumour of horses and accounts for over half of all equine skin tumours. Six types of sarcoid based on gross appearance and clinical behaviour have been described including occult, verrucous, nodular, fibroblastic, mixed and malevolent. Common locations for sarcoid development include the periocular region, ear pinnae, lips, neck, extremities and ventrum (including groin region). Bovine papillomavirus (BPV) is causally associated with equine sarcoid with genetic haplotype, fly vectors and skin trauma identified as potential risk factors for development of the disease. Histopathology is required for definitive diagnosis of equine sarcoid but incomplete excision is thought to activate latent BPV and stimulate growth. Although there are no uniformly effective treatment options, several modalities have been successful in eliminating or managing equine sarcoid. Surgical excision, intratumoural chemotherapy, cryotherapy, hyperthermia, radiotherapy, immunotherapy and immune modulators are used with degrees of success relative to the accessibility and invasiveness of the tumour. Prevention of equine sarcoid may be facilitated by future development of vaccines against bovine papillomavirus.
Influence of crystal form of ipratropium bromide on micronisation and aerosolisation behaviour in dry powder inhaler formulations
Authors: Shur Jagdeep , Kubavat Harshal A , Ruecroft Graham , Hipkiss David , Price Robert 
Published: May 2012

Abstract

Objectives
This study aimed to investigate the relationship between the mechanical properties of anhydrous and monohydrate ipratropium bromide (IB) crystals, their processing behaviour upon air-jet micronisation and aerosolisation performance in dry powder inhaler (DPI) formulations.

Methods
IB monohydrate and anhydrous crystals were produced from seed crystals and supercritical carbon dioxide crystallisation, respectively. Young's modulus of anhydrous and monohydrate IB crystals was determined using nanoindentation. For air-jet micronised crystals, the physicochemical and surface interfacial properties via the cohesive–adhesive balance (CAB) approach were investigated. These data were correlated to in-vitro aerosolisation performance of carrier-based DPI formulations containing either anhydrous or monohydrate IB.

Key findings
Particle size and Young's modulus of both crystals were similar and this was reflected in their similar processing upon micronisation. Particle size of micronised anhydrous and monohydrate crystals were similar. CAB measurements of the micronised particles of monohydrate or anhydrous forms of IB with respect to lactose were 0.70 (R2 = 0.998) and 0.77 (R2 = 0.999), respectively. These data suggested that both samples had similar adhesion to lactose, which correlated with their similar in-vitro aerosolisation performance in DPI formulations.

Conclusions
Monohydrate and anhydrous crystals of IB exhibited similar mechanical properties and interfacial properties upon secondary processing. As a result, the performance of the DPI formulations were similar.
Noncontact ultrasound imaging applied to cortical bone phantoms
Authors: Bulman J. B. , Ganezer K. S. , Halcrow P. W. , Neeson Ian 
Published: May 2012

Purpose:The purpose of this paper was to take the first steps toward applying noncontact ultrasound (NCU) to the tasks of monitoring osteoporosis and quantitative ultrasound imaging (QUS) of cortical bone. The authors also focused on the advantages of NCU, such as its lack of reliance on a technologist to apply transducers and a layer of acoustical coupling gel, the ability of the transducers to operate autonomously as specified by preprogrammed software, and the likely reduction in statistical and systematic errors associated with the variability in the pressure applied by the clinician to the transmitting transducer that NCU might provide. The authors also undertook this study in order to find additional applications of NCU beyond its past limited usage in assessing the severity of third degree burns.Methods:A noncontact ultrasound imaging system using a pair of specially designed broadband, 1.5 MHz noncontact piezoelectric transducers and cortical bone phantoms, were used to determine bone mineral density (BMD), speed of sound (SOS), integrated response (IR), and ultrasonic transmittance. Air gaps of greater than 3 cm, two transmission and two reflection paths, and a digital signal processor were also used in the collection of data from phantoms of nominal mass densities that varied from 1.17 to 2.25 g/cm3 and in bone mineral density from 0 to 1.7 g/cm3.Results:Good correlations between known BMD and measured SOS, IR, and transmittance were obtained for all 17 phantoms, and methods for quantifying and minimizing sources of systematic errors were outlined. The BMD of the phantom sets extended through most of thein vivo range found in cortical bone. A total of 16–20 repeated measurements of the SOS, thickness, and IR for the phantom set that were conducted over a period of several months showed a small variation in the range of measurements of ±1%–2%. These NCU data were shown to be in agreement with similar results using contact ultrasound to be within 1%–2%. Transmittance images of cortical bone phantoms showed differences in the nominal overall BMD values of the phantoms that were large enough to be distinguished by a visual examination. A list of possible sources of errors in quantitative NCU was also included in this study.Conclusions:The results of this paper suggest that NCU might find additional applications in medical imaging, beyond its original and only previous usage in assessing third degree burns. The fact that the authors' phantom measurements using conventional, gel coupled ultrasound are in agreement with those obtained with NCU demonstrates that in spite of large additional levels of attenuation of up to 150 dB and new error sources, NCU could have comparable levels of accuracy to those of conventional quantitative ultrasound, while providing the medical and patient comfort‐related advantages of not involving direct contact.
High‐ratio grid considerations in mobile chest radiography
Authors: Scott Alexander W. , Gauntt David M. , Yester Michael V. , Barnes Gary T. 
Published: May 2012

Purpose:Grids are often not used in mobile chest radiography, and when used, they have a low ratio and are often inaccurately aligned. Recently, a mobile radiography automatic grid alignment system (MRAGA) was developed that accurately and automatically aligns the focal spot with the grid. The objective of this study is to investigate high‐ratio grid tradeoffs in mobile chest radiography at fixed patient dose when the focal spot lies on the focal axis of the grid.Methods:The chest phantoms (medium and large) used in this study were modifications of the ANSI (American National Standards Institute) chest phantom and consisted of layers of Lucite™, aluminum, and air. For the large chest phantom, the amount of Lucite and aluminum was increased by 50% over the medium phantom. Further modifications included a mediastinum insert and the addition of contrast targets in the lung and mediastinum regions. Five high‐ratio grids were evaluated and compared to the nongrid results at x‐ray tube potentials of 80, 90, 100, and 110 kVp for both phantoms. The grids investigated were from two manufacturers: 12:1 and 15:1 aluminum interspace grids from one and 10:1, 13:1, and 15:1 fiber interspace grids from another. MRAGA was employed to align the focal spot with the grid. All exposures for a given kVp and phantom size were made using the same current‐time product (CTP). The phantom images were acquired using computed radiography, and contrast‐to‐noise ratios (CNR) and CNR improvement factors (kCNR) were determined from the resultant images. The noise in the targets and the contrast between the targets and their backgrounds were calculated using a local detrending correction, and the CNR was calculated as the ratio of the target contrast to the background noise. kCNR was defined as the ratio of the CNR imaged with the grid divided by the CNR imaged without a grid.Results:The CNR values obtained with a high‐ratio grid were 4%–65% higher than those obtained without a grid at the same phantom dose. The improvement was greater for the large chest phantom than the medium chest phantom and greater for the mediastinum targets than for the lung targets. In general, the fiber interspace grids performed better than the aluminum interspace grids. In the lung, kCNR for both types of grids exhibited little dependence on kVp or grid ratio. In the mediastinum, kCNR decreased 4%–10% with increasing kVp, and varied up to 5.3% with grid ratio.Conclusions:When the focal spot is accurately aligned with the grid, the use of a high‐ratio grid in mobile chest radiography improves image quality with no increase in dose to the phantom. For the grids studied, the performance of the fiber interspace grids was superior to the performance of the aluminum interspace grids, with the fiber interspace 13:1 grid producing the best overall results for the medium chest phantom and the fiber interspace 15:1 producing the best overall results for the large chest phantom.
Prevalence of
blaZ
Gene Types and the Inoculum Effect with Cefazolin among Bloodstream Isolates of Methicillin-Susceptible Staphylococcus aureus
Authors: Livorsi D. J. , Crispell E. , Satola S. W. , Burd E. M. , Jerris R. , Wang Y. F. , Farley M. M. 
Published: May 2012

ABSTRACT

We sought to define the prevalence of
blaZ
gene types and the inoculum effect to cefazolin among methicillin-susceptible
Staphylococcus aureus
(MSSA) bloodstream infections. The
blaZ
gene was present in 142/185 (77%) isolates. A total of 50 (27%) isolates had a ≥4-fold increase in the cefazolin MIC from a standard to a high inoculum, and 8 (4%) demonstrated a nonsusceptible cefazolin MIC, all type A
blaZ
strains. The efficacy of cefazolin in the presence of the inoculum effect requires further study.
Combination Antimicrobial Susceptibility Testing of Multidrug-Resistant Stenotrophomonas maltophilia from Cystic Fibrosis Patients
Authors: Milne K. E. N. , Gould I. M. 
Published: May 2012

ABSTRACT

Stenotrophomonas maltophilia
is increasingly being isolated from the respiratory tract of individuals with cystic fibrosis, and, because of its multidrug-resistant nature, the selection of suitable treatment regimens can be problematical. Etest methodology was used to facilitate MIC and antimicrobial combination testing on 80 isolates of
S. maltophilia
cultured from the respiratory tract of Scottish individuals with cystic fibrosis between 2001 and 2010. The overall rate of susceptibility for the 1,410 MIC tests was 23.1%, and resistance was 68.9%. The most active antimicrobials were minocycline, co-trimoxazole, and doxycycline, with 92.4%, 87.3%, and 58.8% of isolates being susceptible, respectively. Of the 517 combinations, 13.2% were synergistic, with the most synergistic being ticarcillin/clavulanate plus aztreonam (91.7% synergistic), ticarcillin/clavulanate plus colistin (40%), and ticarcillin/clavulanate plus levofloxacin (19.4%). Colistin plus tobramycin was the only antagonistic combination (0.2%). By the median susceptible breakpoint index, the most active combinations were minocycline plus co-trimoxazole (median index, 20), minocycline plus piperacillin-tazobactam (median, 20), and co-trimoxazole plus ceftazidime (median, 16.5). The increasing problem of multidrug resistance in organisms recovered from the respiratory tracts of individuals with cystic fibrosis is not going to go away. Current susceptibility testing methods do not address the slow-growing organisms associated with chronic infection, and interpretive standards are based on achievable blood levels of antimicrobials. Addressing these issues specifically for organisms recovered from the respiratory tracts of individuals with cystic fibrosis should lead to better therapeutic outcomes and improved wellbeing of individuals with cystic fibrosis.
An Outbreak of Mycoplasma pneumoniae Caused by a Macrolide-Resistant Isolate in a Nursery School in China
Authors: Wang Yong , Qiu Shaofu , Yang Guang , Song Lixue , Su Wenli , Xu Yuanyong , Jia Leili , Wang Ligui , Hao Rongzhang , Zhang Chuanfu , Liu Jingmei , Fu Xiuping , He Jinrong , Zhang Jingshan , Li Zhenjun , Song Hongbin 
Published: May 2012

ABSTRACT

Eighteen out of 45 children were reported to have a respiratory illness during an outbreak at a temporary dormitory in a nursery school in China in 2011. To study the outbreak and to determine the risk factors for infection, an epidemiological investigation was performed. A standardized questionnaire was completed for a total of 45 children with the help of their guardians and parents. In addition, acute- and convalescent-phase serum samples and throat swabs from the children were taken for laboratory diagnosis. The diagnosis of a
Mycoplasma
-like illness was based on the following clinical criteria. The criteria were onset of illness after 31 May 2011, characterized by a cough, fever(>37.5°C), or at least 3 of the following symptoms: fever, sore throat, cough or expectoration, and runny or stuffy nose. PCR-restriction fragment length polymorphism (PCR-RFLP), determination of MICs, and sequencing were performed to determine the genotype, antibiotic resistance, and sequence polymorphisms of the isolated strains, respectively. The paired sera revealed that 15 patients were infected with
Mycoplasma pneumoniae
. Epidemiology confirmed that this was a point source outbreak, characterized by a short incubation period, a high secondary attack rate, and a long period of hospitalization. PCR-RFLP analysis revealed that the 12 isolated strains of
M. pneumoniae
shared the same subtype P1 gene, and 23S rRNA sequence analysis showed that these strains harbored two macrolide-resistant gene-related point mutations at position 2063 and 2617. In this outbreak, the major risk factor was the distance between the bed of the first patient and the beds of close contacts (beds less than three meters apart). The strains isolated in this study were found to harbor two point mutations conferring macrolide resistance, indicating the importance of pathogen and drug resistance surveillance systems.
Optimal Dosing of Miltefosine in Children and Adults with Visceral Leishmaniasis
Authors: Dorlo Thomas P. C. , Huitema Alwin D. R. , Beijnen Jos H. , de Vries Peter J. 
Published: May 2012

ABSTRACT

Only anecdotal data are available on the pharmacokinetics (PK) of miltefosine in children suffering from visceral leishmaniasis (VL). While failure rates were higher in children with VL, steady-state concentrations appeared lower than those seen with adults. We hypothesized that the current linear dosage (in milligrams per kilogram of body weight) is too low for children and that a new dosing algorithm based on an appropriate body size model would result in an optimal exposure. A population PK analysis was performed on three historic pooled data sets, including Indian children, Indian adults, and European adults. Linear and allometric scaling of PK parameters by either body weight or fat-free mass (FFM) was evaluated for body size models. Based on the developed PK model, a dosing algorithm for miltefosine in children and adults was proposed and evaluated
in silico
. The population PK model employing allometric scaling fitted best to the pooled miltefosine data. Allometric scaling by FFM reduced between-subject variability, e.g., for drug clearance, from 49.6% to 32.1%. A new allometric miltefosine dosing algorithm was proposed. Exposure to miltefosine was lower in children than adults receiving 2.5 mg/kg/day: a
C
max
of 18.8 μg/ml was reached by 90% of adults and 66.7% of children. The allometric daily dose resulted in similar levels of exposure to miltefosine for adults and children. The use of a new allometric dosing algorithm for miltefosine in VL patients results in optimal exposure to miltefosine in both adults and children and might improve clinical outcome in children.
The Intermediate Region of Helicobacter pylori VacA Is a Determinant of Toxin Potency in a Jurkat T Cell Assay
Authors: González-Rivera Christian , Algood Holly M. Scott , Radin Jana N. , McClain Mark S. , Cover Timothy L. 
Published: May 2012

ABSTRACT

Colonization of the human stomach with
Helicobacter pylori
is a risk factor for peptic ulceration, noncardia gastric adenocarcinoma, and gastric lymphoma. The secreted VacA toxin is an important
H. pylori
virulence factor that causes multiple alterations in gastric epithelial cells and T cells. Several families of
vacA
alleles have been described, and
H. pylori
strains containing certain
vacA
types (s1, i1, and m1) are associated with an increased risk of gastric disease, compared to strains containing other
vacA
types (s2, i2, and m2). Thus far, there has been relatively little study of the role of the VacA intermediate region (i-region) in toxin activity. In this study, we compared the ability of i1 and i2 forms of VacA to cause functional alterations in Jurkat cells. To do this, we manipulated the chromosomal
vacA
gene in two
H. pylori
strains to introduce alterations in the region encoding the VacA i-region. We did not detect any differences in the capacity of i1 and i2 forms of VacA to cause vacuolation of RK13 cells. In comparison to i1 forms of VacA, i2 forms of VacA had a diminished capacity to inhibit the activation of nuclear factor of activated T cells (NFAT) and suppress interleukin-2 (IL-2) production. Correspondingly, i2 forms of VacA bound to Jurkat cells less avidly than did i1 forms of VacA. These results indicate that the VacA i-region is an important determinant of VacA effects on human T cell function.
Interactions between Polymorphonuclear Leukocytes and Pseudomonas aeruginosa Biofilms on Silicone Implants
In Vivo
Authors: van Gennip Maria , Christensen Louise Dahl , Alhede Morten , Qvortrup Klaus , Jensen Peter Østrup , Høiby Niels , Givskov Michael , Bjarnsholt Thomas 
Published: May 2012

ABSTRACT

Chronic infections with
Pseudomonas aeruginosa
persist because the bacterium forms biofilms that are tolerant to antibiotic treatment and the host immune response. Scanning electron microscopy and confocal laser scanning microscopy were used to visualize biofilm development
in vivo
following intraperitoneal inoculation of mice with bacteria growing on hollow silicone tubes, as well as to examine the interaction between these bacteria and the host innate immune response. Wild-type
P. aeruginosa
developed biofilms within 1 day that trapped and caused visible cavities in polymorphonuclear leukocytes (PMNs). In contrast, the number of cells of a
P. aeruginosa rhlA
mutant that cannot produce rhamnolipids was significantly reduced on the implants by day 1, and the bacteria were actively phagocytosed by infiltrating PMNs. In addition, we identified extracellular wire-like structures around the bacteria and PMNs, which we found to consist of DNA and other polymers. Here we present a novel method to study a pathogen-host interaction in detail. The data presented provide the first direct, high-resolution visualization of the failure of PMNs to protect against bacterial biofilms.
Understanding public trust in services provided by community pharmacists relative to those provided by general practitioners: a qualitative study
Authors: Gidman Wendy , Ward Paul , McGregor Lesley 
Published: May 2012

ObjectivesTo apply sociological theories to understand public trust in extended services provided by community pharmacists relative to those provided by general practitioners (GPs).DesignQualitative study involving focus groups with members of the public.SettingThe West of Scotland.Participants26 purposively sampled members of the public were involved in one of five focus groups. The groups were composed to represent known groups of users and non-users of community pharmacy, namely mothers with young children, seniors and men.ResultsTrust was seen as being crucial in healthcare settings. Focus group discussions revealed that participants were inclined to draw unfavourable comparisons between pharmacists and GPs. Importantly, participants' trust in GPs was greater than that in pharmacists. Participants considered pharmacists to be primarily involved in medicine supply, and awareness of the pharmacist's extended role was low. Participants were often reluctant to trust pharmacists to deliver unfamiliar services, particularly those perceived to be ‘high risk’. Numerous system-based factors were identified, which reinforce patient trust and confidence in GPs, including GP registration and appointment systems, GPs' expert/gatekeeper role and practice environments. Our data indicate that the nature and context of public interactions with GPs fostered familiarity with a specific GP or practice, which allowed interpersonal trust to develop. By contrast, participants' exposure to community pharmacists was limited. Additionally, a good understanding of the GPs' level of training and role promoted confidence.ConclusionCurrent UK initiatives, which aim to implement a range of pharmacist-led services, are undermined by lack of public trust. It seems improbable that the public will trust pharmacists to deliver unfamiliar services, which are perceived to be ‘high risk’, unless health systems change in a way that promotes trust in pharmacists. This may be achieved by increasing the quality and quantity of patient interactions with pharmacists and gaining GP support for extended pharmacy services.