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1.  Regional and temporal variation in the treatment of rheumatoid arthritis across the UK: a descriptive register-based cohort study 
BMJ Open  2012;2(6):e001603.
Objectives
To describe current disease-modifying antirheumatic drugs (DMARDs) prescription in rheumatoid arthritis (RA) with reference to best practice and to identify temporal and regional trends in the UK.
Design
Descriptive, register-based cohort study.
Participants
Permanently registered patients aged ≥18 years with a recorded diagnosis of RA between 1 January 1995 and 31 March 2010 and matched controls. Participants with RA were identified through screening of all patients in the General Practice Research Database (GPRD) with a clinical or referral record for RA and at least 1 day of follow-up.
Setting
639 general practices in the UK supplying data to the GPRD.
Main outcome measures
Medication prescribing between 3 and 12 months of RA diagnosis by region and time period (1995–1999, 2000–2005 and 2006–April 2010).
Results
Of the 35 911 patients in the full RA cohort, 15 259 patients (42%) had incident RA. Analysis of prescribing in incident RA patients demonstrated that between 1995 (baseline) and 2010 there was a substantial increase in DMARD, and specifically methotrexate, prescribing across all regions with a less marked increase in combination DMARD prescribing. Taking 12-month prescribing as a snapshot: DMARD prescribing was 19–49% at baseline increasing to 45–74% by 2006–April 2010; methotrexate prescribing was 4–16% at baseline increasing to 32–60%; combination DMARD prescribing was 0–8% at baseline increasing to 3–17%. However, there was marked regional variation in the proportion of RA patients receiving DMARD regardless of time period.
Conclusions
There has been a substantial increase in prescribing of DMARDs for RA since 1995; however, regional variation persists across the UK with relative undertreatment, according to established best practice. Improved implementation of evidence-based best clinical practice to facilitate removal of treatment variation is warranted. This may occur as a result of the implementation of published national guidance.
doi:10.1136/bmjopen-2012-001603
PMCID: PMC3533005  PMID: 23144258
Primary Care; Rheumatology
2.  High-throughput assessment of bacterial growth inhibition by optical density measurements 
The increasing incidence of antibiotic-resistant bacterial infections both in hospitals and in the community intensifies the need for new antibacterial strategies and targets. Although high-throughput screening against live bacteria allows rapid discovery of compounds with growth-inhibitory activities, these efforts have failed to fill the pipeline with the anticipated antibacterial compounds because target identification is often onerous. Recently, a strategy was reported that employs a bacteria growth inhibition assay readout using optical density measurements on paired strains – both a wildtype strain and a pathway-null mutant – to find inhibitors of wildtype bacterial growth that specifically target conditionally essential enzymes in the pathway of interest. Protocols are provided here for determining the robustness of an assay, screening in a high-throughput format and setting up dose-response curves in paired Staphylococcus aureus strains. However, the protocols can be used to screen for growth-inhibitory compounds in any bacterial strain of interest.
doi:10.1002/9780470559277.ch100115
PMCID: PMC3182142  PMID: 21966637
high-throughput screening; Staphylococcus aureus; optical density; cell-based assay; pathway specific screen; bacterial growth
3.  An Antibiotic That Inhibits a Late Step in Wall Teichoic Acid Biosynthesis Induces the Cell Wall Stress Stimulon in Staphylococcus aureus 
Wall teichoic acids (WTAs) are phosphate-rich, sugar-based polymers attached to the cell walls of most Gram-positive bacteria. In Staphylococcus aureus, these anionic polymers regulate cell division, protect cells from osmotic stress, mediate host colonization, and mask enzymatically susceptible peptidoglycan bonds. Although WTAs are not required for survival in vitro, blocking the pathway at a late stage of synthesis is lethal. We recently discovered a novel antibiotic, targocil, that inhibits a late acting step in the WTA pathway. Its target is TarG, the transmembrane component of the ABC transporter (TarGH) that exports WTAs to the cell surface. We examined here the effects of targocil on S. aureus using transmission electron microscopy and gene expression profiling. We report that targocil treatment leads to multicellular clusters containing swollen cells displaying evidence of osmotic stress, strongly induces the cell wall stress stimulon, and reduces the expression of key virulence genes, including dltABCD and capsule genes. We conclude that WTA inhibitors that act at a late stage of the biosynthetic pathway may be useful as antibiotics, and we present evidence that they could be particularly useful in combination with beta-lactams.
doi:10.1128/AAC.05938-11
PMCID: PMC3318382  PMID: 22290958
4.  The impact of saliva collection and processing methods on CRP, IgE, and Myoglobin immunoassays 
Background
Owing to its ease of collection, saliva is potentially the sample of choice in diagnosis. Salivary biomolecules have provided a porthole in surveying a person’s health and well-being. Our study aims were (1) to demonstrate the effects of pre-analytical steps, collection and pre-processing techniques on salivary protein detection and (2) to establish an indication of salivary reference intervals for 3 biomolecules of clinical interest.
Methods
Saliva samples were collected from participants (n = 25, ages 20–35 years) using the following methods: no stimulation (resting/unstimulated), mechanical, and acid stimulation. The saliva was prepared for analysis by: unprocessed, post standard centrifugation in a container without any additives, and centrifugation using Centrifugal Filter Unit (Amicon® Ultra-0.5). AlphaLisa® assays were used to measure the levels of C-Reactive Protein (CRP), Immunoglobin (IgE) and myoglobin in saliva samples.
Results
Saliva flow rates were lowest with the resting/drooling collection method. The lowest total protein concentration was with acid stimulation. Unstimulated and mechanically stimulated collections produced no effect on the CRP and IgE levels while myoglobin levels were highest with the unstimulated collection. Acid stimulation had a negative impact on the measured concentrations of IgE and myoglobin (except for CRP levels).
Conclusion
Mechanical stimulation was the most viable option for collecting saliva without affecting the levels of CRP and myoglobin. The processing methods had an adverse effect on the concentration of total protein as well as on CRP and IgE concentrations.
doi:10.1186/2001-1326-1-19
PMCID: PMC3560976  PMID: 23369566
Human saliva; Homogeneous bead-based assay; Salivary stimulations; Salivary pre-processing techniques; Non-invasive
5.  Brain Creatine Elevation and NAA Reduction Indicates Neuronal Dysfunction in the Setting of Enhanced Glial Energy Metabolism in a Macaque Model of neuroAIDS 
Proton magnetic resonance spectroscopy (1H MRS) has emerged as one of the most informative neuroimaging modalities for studying the effect of HIV infection in the brain, providing surrogate markers by which to assess disease progression and monitor treatment. Reductions in the level of N-Acetylaspartate (NAA) and NAA/creatine (NAA/Cr) are established markers of neuronal injury or loss. However, the biochemical basis of altered creatine levels in neuroAIDS is not well understood. This study used a rapid progression macaque model of neuroAIDS to elucidate the changes in creatine. As the disease progressed 1H MRS revealed a decrease in NAA, indicative of neuronal injury, and an increase in creatine yet to be elucidated. Subsequently, immunohistochemistry and stereology measures of decreased synaptophysin, microtubule-associated protein 2, and neuronal density confirmed neuronal injury. Furthermore, increases in ionized calcium binding adaptor molecule 1 and glial fibrillary acidic protein indicated microglial and astroglial activation, respectively. Given these data, elevated creatine may reflect enhanced high-energy phosphate turnover in highly metabolizing activated astrocytes and microglia.
doi:10.1002/mrm.22821
PMCID: PMC3139817  PMID: 21381104
HIV; SIV; Macaques; MR Spectroscopy; Creatine; Gliosis
6.  Detection of Favorable Oral Cephalosporin-Clavulanate Interactions by In Vitro Disk Approximation Susceptibility Testing of Extended-Spectrum-Beta-Lactamase-Producing Members of the Enterobacteriaceae 
Journal of Clinical Microbiology  2012;50(3):1023-1026.
Extended-spectrum-beta-lactamase (ESBL)-producing members of the Enterobacteriaceae are often resistant to multiple drug classes, making therapy of urinary infections with oral antibiotics difficult. Previously it was shown that amoxicillin-clavulanate can provide clavulanate inhibition of ESBLs and protect an oral cephalosporin present in combination when tested by broth microdilution. This study has shown that disk approximation testing could detect favorable cephalosporin-clavulanate interactions among a group of 101 previously characterized members of the Enterobacteriaceae with CTX-M, SHV, or TEM ESBLs.
doi:10.1128/JCM.06248-11
PMCID: PMC3295132  PMID: 22170910
7.  Predictors and effects of alcohol use on liver function among young HCV-infected injection drug users in a behavioral intervention 
Journal of hepatology  2010;55(1):45-52.
Background & Aims
Hepatitis C virus (HCV) screening can provide opportunities to reduce disease progression through counseling against alcohol use, but empirical data on this issue are sparse. We determined the efficacy of a behavioral intervention in reducing alcohol use among young, HCV-infected injection drug users (IDUs) (n=355) and assessed whether changes in liver enzymes were associated with changes in alcohol consumption.
Methods
Both the intervention and attention-control groups were counseled to avoid alcohol use, but the intervention group received enhanced counseling. Logistic regression, ANOVA, and continuous time Markov models were used to identify factors associated with alcohol use, changes in mean ALT and AST levels and change in alcohol use post-intervention.
Results
Six months post-intervention, alcohol abstinence increased 22.7% in both groups, with no difference by intervention arm. Transition from alcohol use to abstinence was associated with a decrease in liver enzymes, with a marginally greater decrease in the intervention group (p=0.05 for ALT; p=0.06 for AST). In multivariate Markov models, those who used marijuana transitioned from alcohol abstinence to consumption more rapidly than non-users (RR=3.11); those who were homeless transitioned more slowly to alcohol abstinence (RR=0.47); and those who had ever received a clinical diagnosis of liver disease transitioned more rapidly to abstinence (RR=1.88).
Conclusions
Although, behavioral counseling to reduce alcohol consumption among HCV-infected IDUs had a modest effect, reductions in alcohol consumption were associated with marked improvements in liver function. Interventions to reduce alcohol use among HCV-infected IDUs may benefit from being integrated into clinical care and monitoring of HCV infection.
doi:10.1016/j.jhep.2010.10.028
PMCID: PMC3094600  PMID: 21145862
8.  Synthetic lethal compound combinations reveal a fundamental connection between wall teichoic acid and peptidoglycan biosyntheses in Staphylococcus aureus 
ACS chemical biology  2010;6(1):106-116.
Methicillin resistance in Staphylococcus aureus depends on the production of mecA, which encodes penicillin-binding protein 2A (PBP2A), an acquired peptidoglycan transpeptidase (TP) with reduced susceptibility to beta-lactam antibiotics. PBP2A crosslinks nascent peptidoglycan when the native TPs are inhibited by beta-lactams. Although mecA expression is essential for beta-lactam resistance, it is not sufficient. Here we show that blocking the expression of wall teichoic acids (WTAs) by inhibiting the first enzyme in the pathway, TarO, sensitizes MRSA strains to beta-lactams even though the beta-lactam-resistant transpeptidase, PBP2A, is still expressed. The dramatic synergy between TarO inhibitors and beta-lactams is noteworthy not simply because strategies to overcome methicillin-resistant S. aureus (MRSA) are desperately needed, but because neither TarO nor the activities of the native TPs are essential in MRSA strains. The “synthetic lethality” of inhibiting TarO and the native TPs suggests a functional connection between ongoing WTA expression and peptidoglycan assembly in S. aureus. Indeed, transmission electron microscopy shows that S. aureus cells blocked in WTA synthesis have extensive defects in septation and cell separation, indicating dysregulated cell wall assembly and degradation. Our studies imply that WTAs play a fundamental role in S. aureus cell division and raise the possibility that synthetic lethal compound combinations may have therapeutic utility for overcoming antibiotic resistant bacterial infections.
doi:10.1021/cb100269f
PMCID: PMC3025082  PMID: 20961110
9.  Role of Wall Teichoic Acids in Staphylococcus aureus Endophthalmitis 
This study shows that wall teichoic acids, which are major polyanionic polymer components of the cell wall of Staphylococcus aureus, are necessary for growth and survival of S. aureus in the eye.
Purpose.
Wall teichoic acids (WTAs) are major polyanionic polymer components of the cell wall of Staphylococcus aureus. However, little is known about their role at the host–pathogen interface, especially in endophthalmitis. This study was designed to investigate the extent to which WTAs contribute to the pathogenicity of S. aureus in models of endophthalmitis and to determine whether there would be value in targeting their biosynthesis as a new therapeutic approach.
Methods.
S. aureus RN6390 and its isogenic WTA-null mutant (RN6390ΔtarO) were used to evaluate the role of WTAs in endophthalmitis. RN6390 and RN6390ΔtarO were cultured in bovine vitreous humor (VH) in vitro or inoculated into the vitreous chamber of C57B6 mice. Changes in the number of bacteria, organ function as determined by electroretinography (ERG), and histopathologic changes were assessed throughout the course of infection. In addition, the efficacy of WTA biosynthesis inhibitors in VH in vitro was examined.
Results.
It was observed that a component of VH synergized with WTA biosynthesis inhibitors in vitro and killed the S. aureus. This effect was also seen when mutants incapable of expressing WTA were exposed to VH. The killing activity of VH was lost on treatment with a protease inhibitor. RN6390ΔtarO could not survive in mouse eyes and did not affect organ function, nor was it able to establish endophthalmitis.
Conclusions.
WTAs are essential cellular constituents for the manifestation of virulence by S. aureus in endophthalmitis, and appears to be a viable target for treating the endophthalmitis caused by S. aureus strains.
doi:10.1167/iovs.10-6558
PMCID: PMC3109022  PMID: 21345983
10.  Efficient Construction of Diketopiperazine Macroarrays Through a Cyclative-Cleavage Strategy and Their Evaluation as Luminescence Inhibitors in the Bacterial Symbiont Vibrio fischeri 
Journal of combinatorial chemistry  2009;11(6):1094-1099.
Diketopiperazines (DKPs) are a well-known class of heterocycles that have emerged as a promising biologically active scaffold. Solid-phase organic synthesis has become an important tool in the combinatorial exploration of these privileged structures, expediting the synthesis and, often, the discovery of active compounds. We recently identified several DKPs that are capable of inhibiting the luminescence response of the bacterial symbiont Vibrio fischeri, and we sought to further test the scope of this biological activity. Herein, we report the synthesis of DKP macroarrays using a SPOT-synthesis approach based on an Ugi/DeBoc/Cyclize strategy. Neither a spacer nor a linker was required for macroarray construction on cellulose support, and the cyclative cleavage produced high purity DKPs in good yields. Using this protocol, we prepared a library of 400 DKPs on cellulose support and evaluated its members as luminescence inhibitors in V. fischeri. We found six DKPs capable of inhibiting luminescence by greater than 80% at 500 μM. Collectively, this work serves to further highlight the utility of the small molecule macroarray platform for the synthesis and evaluation of focused libraries.
doi:10.1021/cc900115x
PMCID: PMC3175616  PMID: 19831384
Diketopiperazine; Luminescence; Small molecule macroarray; Spatially addressed solid-phase synthesis; SPOT-synthesis; Ugi four-component reaction; Vibrio fischeri
11.  Social and Health Factors Associated with Physical Activity among Kuwaiti College Students 
Journal of Obesity  2011;2011:512363.
Our aim was to explore the social and health factors that are associated with the level of physical activity among Kuwaiti college students. A random sample of 787 students (48% males and 52% females) was chosen and weight and height were measured to obtain body mass index (BMI, kg/m2). Associated social and health factors were obtained using a questionnaire. Those reporting being physically inactive numbered 354 and the remaining 433 were active. Obesity among males was 13% and was 10.5% among females. The social and health factors that were found to be significantly associated with physical activity among the students were gender (P < .001), marital status (P < .05), BMI category (obese or nonobese) (P < .05), last dental and health checkup (P < .01), desiring a higher degree (P < .001), and countries preferred for visiting (P < .01). Males significantly exceeded females in the practice of physical activity. In conclusion, behavioural modifications, intervention studies, and health education touting the benefits of being physically active should be instituted to increase the practice of sports and other physical activities in order to control and decrease obesity-related morbidity and mortality.
doi:10.1155/2011/512363
PMCID: PMC3092689  PMID: 21603221
12.  Minocycline Inhibition of Monocyte Activation Correlates with Neuronal Protection in SIV NeuroAIDS 
PLoS ONE  2011;6(4):e18688.
Background
Minocycline is a tetracycline antibiotic that has been proposed as a potential conjunctive therapy for HIV-1 associated cognitive disorders. Precise mechanism(s) of minocycline's functions are not well defined.
Methods
Fourteen rhesus macaques were SIV infected and neuronal metabolites measured by proton magnetic resonance spectroscopy (1H MRS). Seven received minocycline (4 mg/kg) daily starting at day 28 post-infection (pi). Monocyte expansion and activation were assessed by flow cytometry, cell traffic to lymph nodes, CD16 regulation, viral replication, and cytokine production were studied.
Results
Minocycline treatment decreased plasma virus and pro-inflammatory CD14+CD16+ and CD14loCD16+ monocytes, and reduced their expression of CD11b, CD163, CD64, CCR2 and HLA-DR. There was reduced recruitment of monocyte/macrophages and productively infected cells in axillary lymph nodes. There was an inverse correlation between brain NAA/Cr (neuronal injury) and circulating CD14+CD16+ and CD14loCD16+ monocytes. Minocycline treatment in vitro reduced SIV replication CD16 expression on activated CD14+CD16+ monocytes, and IL-6 production by monocytes following LPS stimulation.
Conclusion
Neuroprotective effects of minocycline are due in part to reduction of activated monocytes, monocyte traffic. Mechanisms for these effects include CD16 regulation, reduced viral replication, and inhibited immune activation.
doi:10.1371/journal.pone.0018688
PMCID: PMC3071838  PMID: 21494695
13.  Development of Improved Inhibitors of Wall Teichoic Acid Biosynthesis with Potent Activity Against Staphylococcus aureus 
A small molecule (1835F03) that inhibits Staphylococcus aureus wall teichoic acid biosynthesis, a proposed antibiotic target, has been discovered. Rapid, parallel, solution-phase synthesis was employed to generate a focused library of analogs, providing detailed information about structure-activity relationships and leading to the identification of targocil, a potent antibiotic.
doi:10.1016/j.bmcl.2010.01.036
PMCID: PMC2844852  PMID: 20138521
Wall teichoic acids (WTAs); Staphylococcus aureus; antibiotic; bacteriostatic; structure-activity relationship (SAR); triazoloquinazoline; targocil
14.  Evc2 is a positive modulator of Hedgehog signalling that interacts with Evc at the cilia membrane and is also found in the nucleus 
BMC Biology  2011;9:14.
Background
Evc is essential for Indian Hedgehog (Hh) signalling in the cartilage growth plate. The gene encoding Evc2 is in close proximity in divergent orientation to Evc and mutations in both human genes lead to the chondrodysplasia Ellis-van Creveld syndrome.
Results
Bioinformatic analysis reveals that the Evc and Evc2 genes arose through a duplication event early in metazoan evolution and were subsequently lost in arthropods and nematodes. Here we demonstrate that Evc2 is essential for Hh pathway activation in response to the Smo agonist purmorphamine. A yeast two-hybrid screen using Evc as bait identified Evc2 as an Evc binding partner and we confirmed the interaction by immunoprecipitation. We developed anti-Evc2 antibodies and show that Evc2 and Evc co-localize at the basal body and also on primary cilia. In transfected cells, basal body and cilia localization is observed when Evc and Evc2 constructs are co-transfected but not when either construct is transfected individually. We show that Evc and Evc2 are cilia transmembrane proteins, the C-terminus for both being intracellular and Evc2, but not Evc, having an extracellular portion. Furthermore, Evc is absent at the basal body in Evc2 null cells. Using Western blots of cytoplasmic and nuclear protein, we also demonstrate that full length Evc2 but not Evc, is located in the nucleus.
Conclusions
We demonstrate for the first time that Evc2 is a positive regulator of the Hh signalling pathway and that it is located at the basal body of primary cilia. We show that the presence of Evc and Evc2 at the basal body and cilia membrane is co-dependent. In addition, Evc2, but not Evc, is present in the cell nucleus suggesting movement of Evc2 between the cilium and nucleus.
doi:10.1186/1741-7007-9-14
PMCID: PMC3052239  PMID: 21356043
15.  Supervising Structured Learning Experiences for Students in New Jersey: Training Teachers in School-Based Occupational Health and Safety Practice 
Public Health Reports  2009;124(Suppl 1):74-83.
SYNOPSIS
This article describes the structured learning experience (SLE) supervisory training curriculum coordinated by the New Jersey Safe Schools Program, a project supported by the New Jersey Department of Education, Office of Career and Technical Education. The New Jersey SLE supervisory training program comprises training courses and resources for teachers who supervise secondary school minors (students aged 16 to 18 years and special needs students up to age 21) enrolled in various programs—college preparatory, general education, career and technical education, career academies, and special education. One goal of the program is to enhance knowledge and awareness of legal and scientific occupational safety and health principles to ensure safe, rewarding work experiences inside and outside classrooms.
This article describes our experiences and data available from November 2005 to January 2008. We summarize relevant federal and state laws and agencies; potential exposure agents and microenvironments of concern; stakeholders and training partners; process and immediate impact data from SLE supervisory trainings; and lessons learned to inform states that may adopt similar strategies or regulations.
PMCID: PMC2708658  PMID: 19618809
16.  In Vitro Antimicrobial Activity of Wall Teichoic Acid Biosynthesis Inhibitors against Staphylococcus aureus Isolates ▿ †  
Staphylococcus aureus is the leading cause of invasive and superficial human infections, is increasingly antibiotic resistant, and is therefore the target for the development of new antimicrobials. Compounds (1835F03 and targocil) were recently shown to function as bacteriostatic inhibitors of wall teichoic acid (WTA) biosynthesis in S. aureus. To assess the value of targeting WTA biosynthesis in human infection, it was therefore of interest to verify the involvement of WTA in bacterial binding to human corneal epithelial cells (HCECs) and to assess the activities of inhibitors of WTA biosynthesis against clinical isolates of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) from cases of human keratitis. The 1835F03 MIC90s were 8 μg/ml for MSSA keratitis isolates and >32 μg/ml for MRSA keratitis isolates. The MIC90 for the analog of 1835F03, targocil, was 2 μg/ml for both MRSA and MSSA. Targocil exhibited little toxicity at concentrations near the MIC, with increased toxicity occurring at higher concentrations and with longer exposure times. Targocil activity was moderately sensitive to the presence of serum, but it inhibited extracellular and intracellular bacteria in the presence of HCECs better than vancomycin. Targocil-resistant strains exhibited a significantly reduced ability to adhere to HCECs.
doi:10.1128/AAC.00879-10
PMCID: PMC3028815  PMID: 21098254
17.  Antimicrobial Susceptibilities of Health Care-Associated and Community-Associated Strains of Methicillin-Resistant Staphylococcus aureus from Hospitalized Patients in Canada, 1995 to 2008▿  
We determined the in vitro antimicrobial susceptibilities of 7,942 methicillin-resistant Staphylococcus aureus (MRSA) isolates obtained from patients hospitalized in 48 Canadian hospitals from 1995 to 2008. Regional variations in susceptibilities were identified. The dissemination of community-associated strains in Canada appears to have contributed to increased susceptibility of MRSA to several non-β-lactam antimicrobial agents in the past decade. Reduced susceptibility to glycopeptides was not identified.
doi:10.1128/AAC.01717-09
PMCID: PMC2863599  PMID: 20231402
18.  Discovery of a Small Molecule that Blocks Wall Teichoic Acid Biosynthesis in Staphylococcus aureus 
ACS chemical biology  2009;4(10):875-883.
Both Gram-positive and Gram-negative bacteria contain bactoprenol-dependent biosynthetic pathways expressing non-essential cell surface polysaccharides that function as virulence factors. Although these polymers are not required for bacterial viability in vitro, genes in many of the biosynthetic pathways are conditionally essential: they cannot be deleted except in strains incapable of initiating polymer synthesis. We report a cell-based, pathway-specific strategy to screen for small molecule inhibitors of conditionally essential enzymes. The screen identifies molecules that prevent the growth of a wildtype bacterial strain but do not affect the growth of a mutant strain incapable of initiating polymer synthesis. We have applied this approach to discover inhibitors of wall teichoic acid (WTA) biosynthesis in Staphylococcus aureus. WTAs are anionic cell surface polysaccharides required for host colonization that have been suggested as targets for new antimicrobials. We have identified a small molecule, 7-chloro-N,N-diethyl-3-(phenylsulfonyl)-[1,2,3]triazolo[1,5-a]quinolin-5-amine (1835F03), that inhibits the growth of a panel of S. aureus strains (MIC = 1–3 μg mL−1), including clinical methicillin-resistant S. aureus (MRSA) isolates. Using a combination of biochemistry and genetics, we have identified the molecular target as TarG, the transmembrane component of the ABC transporter that exports WTAs to the cell surface. We also show that preventing the completion of WTA biosynthesis once it has been initiated triggers growth arrest. The discovery of 1835F03 validates our chemical genetics strategy for identifying inhibitors of conditionally essential enzymes, and the strategy should be applicable to many other bactoprenol-dependent biosynthetic pathways in the pursuit of novel antibacterials and probes of bacterial stress response.
doi:10.1021/cb900151k
PMCID: PMC2787957  PMID: 19689117
19.  Factors Associated with Overweight and Obesity among Kuwaiti Elementary Male School Children Aged 6–10 Years 
Background. Childhood obesity is becoming a global epidemic which may result in increased morbidity and mortality during young adulthood. Objectives. To identify factors associated with overweight and that of obesity among Kuwaiti elementary male school children aged 6–10 years. Methods. Weights and heights of 662 students at a randomly selected school were collected to obtain body mass index (BMI). Results. The prevalence of overweight and obesity among the students were 20.2% and 16.8%, respectively. There were a variety of factors associated with overweight and obesity; however, having one or more obese brother, an unemployed father, or a high (>11) number of persons living at home was significantly associated with higher risk of overweight and obesity. Increased age and school level as well as having a chronic disease were associated with the risk of overweight. Conclusion. Health education programs for families should be implemented to help control overweight and obesity in Kuwaiti children.
doi:10.1155/2010/459261
PMCID: PMC2945653  PMID: 20886010
20.  Regional Profiling for Determination of Genotype Diversity of Mastitis-Specific Staphylococcus aureus Lineage in Canada by Use of Clumping Factor A, Pulsed-Field Gel Electrophoresis, and spa Typing▿  
Journal of Clinical Microbiology  2009;48(2):375-386.
One of the major concerns in global public health and the dairy industry is the emergence of host-specific virulent Staphylococcus aureus strains. The high degree of stability of the species genome renders detection of genetic microvariations difficult. Thus, approaches for the rapid tracking of specialized lineages are urgently needed. We used clumping factor A (clfA) to profile 87 bovine mastitis isolates from four regions in Canada and compared the results to those obtained by pulsed-field gel electrophoresis (PFGE) and spa typing. Twenty-five pulsotypes were obtained by PFGE with an index of discrimination of 0.91. These were assigned to six PFGE lineage groups A to F and seven spa types, including two novel ones. Group A had 48.3% of the isolates and group D had 43.7% of the isolates, while only 8% of the isolates were variable. The results of antimicrobial susceptibility testing indicated that all isolates were sensitive to methicillin and the non-beta-lactam antibiotics, while three isolates were resistant to penicillin and one isolate was resistant to tetracycline. All isolates had the clfA gene and belonged to 20 clfA repeat types with an index of discrimination of 0.90. The dominant clfA types, types X, Q, C, and Z, formed 82% and 43% of PFGE groups A and D, respectively, and had copy numbers that varied only within a narrow range of between 46 and 52 copies, implying clonal selection. The rest were variable and region specific. Furthermore, the dominant groups contained subpopulations in different regions across Canada. Sequence information confirmed the relatedness obtained by the use of clfA repeat copy numbers and other methods and further revealed the occurrence of full-repeat deletions and conserved host-specific codon-triplet position biases at 18-bp units. Thus, concordant with the results of PFGE and spa typing, clfA typing proved useful for revealing the clonal nature of the mastitis isolate lineage and for the rapid profiling of subpopulations with comparable discriminatory powers.
doi:10.1128/JCM.01768-09
PMCID: PMC2815643  PMID: 19955267
21.  Integrative Genomic Analyses Identify BRF2 as a Novel Lineage-Specific Oncogene in Lung Squamous Cell Carcinoma 
PLoS Medicine  2010;7(7):e1000315.
William Lockwood and colleagues show that the focal amplification of a gene, BRF2, on Chromosome 8p12 plays a key role in squamous cell carcinoma of the lung.
Background
Traditionally, non-small cell lung cancer is treated as a single disease entity in terms of systemic therapy. Emerging evidence suggests the major subtypes—adenocarcinoma (AC) and squamous cell carcinoma (SqCC)—respond differently to therapy. Identification of the molecular differences between these tumor types will have a significant impact in designing novel therapies that can improve the treatment outcome.
Methods and Findings
We used an integrative genomics approach, combing high-resolution comparative genomic hybridization and gene expression microarray profiles, to compare AC and SqCC tumors in order to uncover alterations at the DNA level, with corresponding gene transcription changes, which are selected for during development of lung cancer subtypes. Through the analysis of multiple independent cohorts of clinical tumor samples (>330), normal lung tissues and bronchial epithelial cells obtained by bronchial brushing in smokers without lung cancer, we identified the overexpression of BRF2, a gene on Chromosome 8p12, which is specific for development of SqCC of lung. Genetic activation of BRF2, which encodes a RNA polymerase III (Pol III) transcription initiation factor, was found to be associated with increased expression of small nuclear RNAs (snRNAs) that are involved in processes essential for cell growth, such as RNA splicing. Ectopic expression of BRF2 in human bronchial epithelial cells induced a transformed phenotype and demonstrates downstream oncogenic effects, whereas RNA interference (RNAi)-mediated knockdown suppressed growth and colony formation of SqCC cells overexpressing BRF2, but not AC cells. Frequent activation of BRF2 in >35% preinvasive bronchial carcinoma in situ, as well as in dysplastic lesions, provides evidence that BRF2 expression is an early event in cancer development of this cell lineage.
Conclusions
This is the first study, to our knowledge, to show that the focal amplification of a gene in Chromosome 8p12, plays a key role in squamous cell lineage specificity of the disease. Our data suggest that genetic activation of BRF2 represents a unique mechanism of SqCC lung tumorigenesis through the increase of Pol III-mediated transcription. It can serve as a marker for lung SqCC and may provide a novel target for therapy.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Lung cancer is the commonest cause of cancer-related death. Every year, 1.3 million people die from this disease, which is mainly caused by smoking. Most cases of lung cancer are “non-small cell lung cancers” (NSCLCs). Like all cancers, NSCLC starts when cells begin to divide uncontrollably and to move round the body (metastasize) because of changes (mutations) in their genes. These mutations are often in “oncogenes,” genes that, when activated, encourage cell division. Oncogenes can be activated by mutations that alter the properties of the proteins they encode or by mutations that increase the amount of protein made from them, such as gene amplification (an increase in the number of copies of a gene). If NSCLC is diagnosed before it has spread from the lungs (stage I disease), it can be surgically removed and many patients with stage I NSCLC survive for more than 5 years after their diagnosis. Unfortunately, in more than half of patients, NSCLC has metastasized before it is diagnosed. This stage IV NSCLC can be treated with chemotherapy (toxic chemicals that kill fast-growing cancer cells) but only 2% of patients with stage IV lung cancer are alive 5 years after diagnosis.
Why Was This Study Done?
Traditionally, NSCLC has been regarded as a single disease in terms of treatment. However, emerging evidence suggests that the two major subtypes of NSCLC—adenocarcinoma and squamous cell carcinoma (SqCC)—respond differently to chemotherapy. Adenocarcinoma and SqCC start in different types of lung cell and experts think that for each cell type in the body, specific combinations of mutations interact with the cell type's own unique characteristics to provide the growth and survival advantage needed for cancer development. If this is true, then identifying the molecular differences between adenocarcinoma and SqCC could provide targets for more effective therapies for these major subtypes of NSCLC. Amplification of a chromosome region called 8p12 is very common in NSCLC, which suggests that an oncogene that drives lung cancer development is present in this chromosome region. In this study, the researchers investigate this possibility by looking for an amplified gene in the 8p12 chromosome region that makes increased amounts of protein in lung SqCC but not in lung adenocarcinoma.
What Did the Researchers Do and Find?
The researchers used a technique called comparative genomic hybridization to show that focal regions of Chromosome 8p are amplified in about 40% of lung SqCCs, but that DNA loss in this region is the most common alteration in lung adenocarcinomas. Ten genes in the 8p12 chromosome region were expressed at higher levels in the SqCC samples that they examined than in adenocarcinoma samples, they report, and overexpression of five of these genes correlated with amplification of the 8p12 region in the SqCC samples. Only one of the genes—BRF2—was more highly expressed in squamous carcinoma cells than in normal bronchial epithelial cells (the cell type that lines the tubes that take air into the lungs and from which SqCC develops). Artificially induced expression of BRF2 in bronchial epithelial cells made these normal cells behave like tumor cells, whereas reduction of BRF2 expression in squamous carcinoma cells made them behave more like normal bronchial epithelial cells. Finally, BRF2 was frequently activated in two early stages of squamous cell carcinoma—bronchial carcinoma in situ and dysplastic lesions.
What Do These Findings Mean?
Together, these findings show that the focal amplification of chromosome region 8p12 plays a role in the development of lung SqCC but not in the development of lung adenocarcinoma, the other major subtype of NSCLC. These findings identify BRF2 (which encodes a RNA polymerase III transcription initiation factor, a protein that is required for the synthesis of RNA molecules that help to control cell growth) as a lung SqCC-specific oncogene and uncover a unique mechanism for lung SqCC development. Most importantly, these findings suggest that genetic activation of BRF2 could be used as a marker for lung SqCC, which might facilitate the early detection of this type of NSCLC and that BRF2 might provide a new target for therapy.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000315.
The US National Cancer Institute provides detailed information for patients and professionals about all aspects of lung cancer, including information on non-small cell carcinoma (in English and Spanish)
Cancer Research UK also provides information about lung cancer and information on how cancer starts
MedlinePlus has links to other resources about lung cancer (in English and Spanish)
doi:10.1371/journal.pmed.1000315
PMCID: PMC2910599  PMID: 20668658
22.  Proton Magnetic Resonance Spectroscopy Reveals Neuroprotection by Oral Minocycline in a Nonhuman Primate Model of Accelerated NeuroAIDS 
PLoS ONE  2010;5(5):e10523.
Background
Despite the advent of highly active anti-retroviral therapy (HAART), HIV-associated neurocognitive disorders continue to be a significant problem. In efforts to understand and alleviate neurocognitive deficits associated with HIV, we used an accelerated simian immunodeficiency virus (SIV) macaque model of NeuroAIDS to test whether minocycline is neuroprotective against lentiviral-induced neuronal injury.
Methodology/Principal Findings
Eleven rhesus macaques were infected with SIV, depleted of CD8+ lymphocytes, and studied until eight weeks post inoculation (wpi). Seven animals received daily minocycline orally beginning at 4 wpi. Neuronal integrity was monitored in vivo by proton magnetic resonance spectroscopy and post-mortem by immunohistochemistry for synaptophysin (SYN), microtubule-associated protein 2 (MAP2), and neuronal counts. Astrogliosis and microglial activation were quantified by measuring glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (IBA-1), respectively. SIV infection followed by CD8+ cell depletion induced a progressive decline in neuronal integrity evidenced by declining N-acetylaspartate/creatine (NAA/Cr), which was arrested with minocycline treatment. The recovery of this ratio was due to increases in NAA, indicating neuronal recovery, and decreases in Cr, likely reflecting downregulation of glial cell activation. SYN, MAP2, and neuronal counts were found to be higher in minocycline-treated animals compared to untreated animals while GFAP and IBA-1 expression were decreased compared to controls. CSF and plasma viral loads were lower in MN-treated animals.
Conclusions/Significance
In conclusion, oral minocycline alleviates neuronal damage induced by the AIDS virus.
doi:10.1371/journal.pone.0010523
PMCID: PMC2866543  PMID: 20479889
23.  Current trends in the treatment of asthma: focus on the simultaneous administration of salmeterol/fluticasone 
Asthma is a chronic disease of the airways that affects over 20 million people in the United States. It is a complex disease that involves airway infiltration by different types of cells and cell mediators causing chronic inflammation of the airway as well as hyper-responsiveness and edema. Management of asthma symptoms often requires combination therapy with multiple medications. Long-acting beta-2 agonists and inhaled corticosteroids have become key medications in the prevention of asthma exacerbations. The bronchodilatory effects of the beta-2 agonists coupled with the anti-inflammatory action of the corticosteroids combat the multi-factorial causes of asthma. The combination inhaler containing salmeterol and fluticasone is one such product that has been proven safe and effective for asthma therapy.
PMCID: PMC3047914  PMID: 21437034
asthma; fluticasone; salmeterol; beta-2 agonist; inhaled corticosteroid
24.  Wall Teichoic Acid Function, Biosynthesis, and Inhibition 
doi:10.1002/cbic.200900557
PMCID: PMC2798926  PMID: 19899094
antibiotics; biosynthesis; conditionally essential enzymes; Gram-positive bacteria; wall teichoic acid (WTA)
25.  A preliminary guideline for the assignment of methicillin-resistant Staphylococcus aureus to a Canadian pulsed-field gel electrophoresis epidemic type using spa typing 
BACKGROUND
Increasing rates of methicillin-resistant Staphylococcus aureus (MRSA) infections on a global scale is a major health concern. In Canada, there are 10 known epidemic types of MRSA as determined by pulsed-field gel electrophoresis (PFGE). Despite the excellent discriminatory power of PFGE, there are several disadvantages of using this technique, such as high degree of labour intensity and the inability to easily develop an MRSA typing database due to the subjective interpretation of results.
OBJECTIVES
The purpose of the present study was to determine whether spa typing, an established DNA sequence-based typing method, could be used as an alternative to PFGE for the typing of Canadian MRSA (CMRSA) epidemic isolates.
RESULTS
spa types were determined for 1488 CMRSA isolates, and the method was analyzed for its ability to identify and cluster CMRSA1-10 strains. Minimal spanning tree analysis of 1452 spa types revealed individual clonal clusters for PFGE epidemic types CMRSA1, 2, 7 and 8, but spa typing could not distinguish CMRSA5 from CMRSA9 and CMRSA10, and CMRSA3 from CMRSA4 and CMRSA6. However, specific spa types were generally associated with only one PFGE epidemic type. Based on these results, a spa typing guideline for CMRSA isolates was developed and tested using the first 300 MRSA isolates received in 2007 through the Canadian Nosocomial Infection Surveillance Program.
CONCLUSIONS
The high concordance of spa types with PFGE epidemic types using this guideline demonstrated the feasibility of spa typing as a more rapid and less technically demanding alternative typing method for MRSA in Canada.
PMCID: PMC2604773  PMID: 19436507
Canada; CNISP; Methicillin-resistant Staphylococcus aureus; Pulsed-field gel electrophoresis; spa typing

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