244 results on '"Jones RO"'
Search Results
2. How to Create a Coaching Culture: A Practical Introduction
- Author
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Gillian Jones, Ro Gorell
- Published
- 2018
3. Staffing and Outcomes
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Jones, Ro
- Published
- 2008
4. A Blueprint for a Contemporary Storage Element, building a new WLCG storage system with widely available hardware and software components: Ceph, XRootD, and Prometheus
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Jones Roger, Doidge Matt, Hand Gerard, Love Peter, and Simpson Steven
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Physics ,QC1-999 - Abstract
When a new long-term storage facility was needed at the Lancaster WLCG Tier-2 Site, an architecture was chosen involving CephFS as a failure-tolerant back-end volume, and load-balanced XRootD as an endpoint exposing the volume via the HTTPS/DAVS protocols increasingly favoured by the WLCG and other users. This allows operations to continue in the face of disc/node failures with minimal management, and enables good utilization of network connectivity for remote access. We deployed a Prometheus/Loki/Grafana monitoring/alerting stack for timely detection and resolution of failures in such a production environment. Some custom scripts were required to adapt the off-the-shelf functional components with monitoring. With such a monitoring system in place, failures such as disc defects, data corruption and resource exhaustion in long-running processes can be anticipated, and their management planned. We describe the hardware platform and our requirements on it, and detail the software architecture from initial design, through adaptations to face challenges encountered during production, to present condition. Developments and contributions to related projects that help to fully exploit our design decisions are described. We include performance metrics of the system, the lessons learned during production, and our future plans.
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- 2024
- Full Text
- View/download PDF
5. In memory of Professor Ronald W. Jones
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Jones Ronald W.
- Subjects
Business ,HF5001-6182 - Published
- 2022
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6. Pathogenesis of pre-eclampsia: marinobufagenin and angiogenic imbalance as biomarkers of the syndrome.
- Author
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Uddin MN, Allen SR, Jones RO, Zawieja DC, and Kuehl TJ
- Abstract
Pre-eclampsia (preE), a pregnancy disorder with the de novo onset of hypertension and proteinuria after 20 weeks of gestation, has multiple triggers that initiate pathophysiologic mechanisms. This review addresses translational aspects of preE by synthesizing information on preE pathogenesis, describing diagnostic biomarkers that predict disease, and suggesting strategies to lessen adverse outcomes. Key to this understanding is the role of cardiotonic bufodienolides, with marinobufagenin (MBG) as the prototype, and angiogenic factors in preE pathogenesis. Data from a rat model believed to mimic human preE show that urinary excretion of MBG increases before the onset of hypertension and proteinuria and that affected animals have an increased vascular leakage and blood brain barrier permeability. Angiogenic imbalance occurs with the onset of the syndrome in this model. Also, we report that MBG levels in preE patients exceed those in normal pregnancy and that angiogenic factors are altered in patients showing signs and symptoms of overt disease. In vitro administration of MBG inhibits cytotrophoblast function and triggers hyperpermeability in endothelial cell monolayers. We advance the hypotheses that MBG precedes preE; MBG causes disruption of tight junction proteins leading to vascular leak via activation of MAPK which triggers apoptotic mechanisms resulting in further endothelial dysfunction leading to edema with the release of angiogenic factors. This review provides new evidence about the role of MBG and vasoactive intermediates in preE pathogenesis including the neurologic sequela and may reveal new therapeutic targets for the prevention of preE complications. [ABSTRACT FROM AUTHOR]
- Published
- 2012
7. Docosahexaenoic acid therapy in peroxisomal diseases: results of a double-blind, randomized trial.
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Paker AM, Sunness JS, Brereton NH, Speedie LJ, Albanna L, Dharmaraj S, Moser AB, Jones RO, Raymond GV, Paker, A M, Sunness, J S, Brereton, N H, Speedie, L J, Albanna, L, Dharmaraj, S, Moser, A B, Jones, R O, and Raymond, G V
- Published
- 2010
- Full Text
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8. Prophylactic antibiotics in surgery for chronic ear disease.
- Author
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Hester TO, Jones RO, Hester, T O, and Jones, R O
- Abstract
Objectives/hypothesis: The role of prophylactic antibiotics in otologic surgery continues to be debated and perhaps misused. Prior studies have provided conflicting evidence with regard to the benefit obtained from the use of prophylactic antibiotics in surgery for chronic otitis media. The current study was designed to evaluate the role of prophylactic antibiotics in the outcomes of surgery for chronic ear disease. It was the authors' impression that there was no indication for prophylactic antibiotics in such surgery.Study Design: Randomized prospective study performed in a tertiary care facility.Methods: Patients who met inclusion criteria (n = 146) were randomly assigned to an antibiotic treatment group or a control group receiving no prophylactic antibiotics. Patients in the antibiotic treatment group were given preoperative intravenous antibiotics followed by oral antibiotics for 5 days after surgery. Patients were followed postoperatively and observed for clinical evidence of infection and graft failure.Results: There was no statistically significant difference between the two groups with regard to the incidence of postoperative infection or graft survival.Conclusions: The use of prophylactic antibiotics in surgery for chronic ear disease cannot be recommended based on the findings of this study. [ABSTRACT FROM AUTHOR]- Published
- 1998
9. Expected neurologic outcomes for surgical treatment of cervical neurilemomas.
- Author
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Valentino J, Boggess MA, Ellis JL, Hester TO, Jones RO, Valentino, J, Boggess, M A, Ellis, J L, Hester, T O, and Jones, R O
- Abstract
Objective: Neurilemomas are classically described as fusiform tumors that eccentrically displace the undisturbed neural fascicles. The authors seek to clarify the relationship of cervical neurilemomas to their nerve of origin and assess the functional outcome of surgical extirpation.Study Design: A retrospective review of clinical, intraoperative, and histopathologic data of six patients with cervical extracranial neurilemomas.Methods: Additional histochemical staining of the pathologic specimens was performed to evaluate the tumor for neurites. A comprehensive literature review of cervical neurilemoma cases and meta-analysis of clinical outcomes in these cases were performed.Results: In the series of five consecutive cervical neurilemomas, only one was an eccentric mass pushing the undisturbed nerve aside. In the five other cases, excision of the neurilemoma required complete nerve excision. Neural elements traveling through the central portions of the tumor were clearly demonstrated histologically. Collective analysis of the literature on cervical neurilemomas revealed that although some cases allow nerve preservation, preservation of function is frequently poor.Conclusions: This experience and that reported in the literature suggest that it is frequently impossible to preserve the function of the nerve of origin with surgical treatment of cervical neurilemomas. [ABSTRACT FROM AUTHOR]- Published
- 1998
10. Prophylactic antibiotic drops after tympanostomy tube placement.
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Hester TO, Jones RO, Archer SM, and Haydon RC
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- 1995
11. Hydrocephalus-associated hearing loss and resolution after ventriculostomy.
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Dixon JF and Jones RO
- Published
- 2012
12. The clinical reliability of vestibular evoked myogenic potentials.
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Bush ML, Jones RO, and Shinn JB
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MYOBLASTS , *OTOLARYNGOLOGY , *AUDIOLOGY , *MUSCLES , *STERNOCLEIDOMASTOID muscle - Abstract
Vestibular evoked myogenic potential (VEMP) testing has gained popularity as a diagnostic modality in otolaryngology and audiology. To maximize the utility of this test, examiners need the availability of ideal test settings and reliable norms. We conducted a prospective study of 8 subjects with no history of neurotologic symptoms to examine the test-retest consistency of VEMP testing and to analyze the impact of stimulus type and muscle tension monitoring. All subjects underwent VEMP testing with two stimuli: a 500-Hz tone and a click. With each stimulus, testing was completed with and without monitoring of sternocleidomastoid muscle tension. All subjects participated in an initial testing session and then returned for a repeat testing session 2 to 4 weeks later. We measured the amplitude of primary waveforms P13 (first positive peak)and N23 (first negative peak) and analyzed the reliability and reproducibility of the mean amplitude asymmetry of these VEMP peaks. The P13 component of the VEMP (specificity: 86.25%) demonstrated a more stable amplitude than did the N23 component (specificity: 70.50%). Therefore, our statistical analysis of the effect of stimulus type and muscle tension monitoring on test-retest reliability was limited to the P13 waveform. We found that neither the type of stimulus nor the presence or absence of muscle tension monitoring had any statistically significant effect on amplitude asymmetry. We concluded that in VEMP testing, the P13 component was more specific than the N23 component in identifying normal subjects and that the P13 component provided consistent results across test sessions, regardless of the type of stimulus or the presence or absence of muscle tension monitoring. [ABSTRACT FROM AUTHOR]
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- 2010
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13. Serum zinc and copper levels in maintenance haemodialysis patients and its relationship with depression and anxiety
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R Sudha, K Ponsuganthi, and Jones Ronald
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Haemodialysis, Depression, Anxiety, Serum Zinc, Serum Copper ,Medicine - Abstract
Hemodialysis (HD) patients are at risk for both deficiency, and accumulation of trace elements, although the data remains controversial. Low serum zinc level is associated with major depression in the general population; and copper interferes with zinc levels since it shares the same absorption pathways as zinc. Previous data suggest a possible zinc deficiency and copper excess is associated with depression in haemodialysis patients. The aims of this study are to assess depression and anxiety in HD patients using the Beck Depression Inventory and Beck Anxiety Inventory scoring system, and, to determine the association of serum zinc and copper levels with depression and anxiety in HD patients. A cross sectional study was conducted on 65 Haemodialysis patients stratified across equal numbers of study subjects relevant to age and sex; and compared to an apparently healthy cohort of individuals over a period of 3 months. All study subjects were analyzed for serum zinc, copper, urea, creatinine, haemoglobin and albumin after collecting detailed demographic data. Anxiety and depression were assessed by using the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) scoring system. The results of this study demonstrated that 89% and 98 % of haemodialysis patients suffered from depression and anxiety respectively. The mean levels of serum zinc and albumin were 56.25 ± 22.85 µg/dl vs 83.8 ± 18.12 µg/dl and 3.14 ± 0.49 gm/dl vs 3.95 ± 0.37 gm/dl respectively; which were significantly decreased in HD patients when compared to controls. A negative correlation was found between serum zinc levels and severity of depression; but, not for anxiety in HD patients. Serum copper levels in haemodialysis patients were indifferent from the controls (118.2 ± 41.59 µg/dl vs 102.23 ± 30 µg/dl). This study concluded that the majority of patients undergoing chronic haemodialysis were severely depressed and anxious. Patients on regular haemodialysis had decreased zinc levels and had more severe psychiatric disturbances than others.
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- 2015
14. Ability of Latin America laboratories to detect antimicrobial resistance patterns: experience of the SENTRY antimicrobial surveillance program (1997-2000)
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Mendes Rodrigo E., Reis Adriana O., Gales Ana C., Jones Ronald N., and Sader Hélio S.
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Antimicrobial susceptibility test ,antimicrobial resistance pattern ,quality assurance ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
The accuracy of antimicrobial susceptibility tests is a crucial step for the clinical management of patients with serious infections. They must be reliable and precise because they will guide antimicrobial therapy. Our main objective was to compare the results of susceptibility testing performed by the SENTRY coordinator laboratory with those reported by the participating Latin American medical centers. A total of 10,277 bacterial isolates were tested by the reference broth microdilution method at the coordinator laboratory in the United States. The tests were performed and interpreted following the National Committee for Clinical Laboratory Standards (NCCLS) recommendations. Ten antimicrobial agent-organism combinations were analyzed. The susceptibility methods utilized in each of the medical centers were also evaluated. Total agreement of the results was obtained in nearly 88% of the antimicrobial agent-organism combinations. "Very major" (false-susceptible results) and "major errors" (false-resistant results) were observed in 12% and 6% of the cases, respectively. The highest disagreements were observed for coagulase-negative Staphylococcus - oxacillin (20% - very major error) and Burkholderia cepacia - imipenem (21% - very major error). The susceptibility method with the highest agreement rate was Etest® (92%) > PASCO® (91%) > agar dilution (91%) > MicroScan® (90%) > Vitek® (87%). External quality assurance data obtained by surveillance programs such as the SENTRY Antimicrobial Surveillance Program are not only helpful for detecting the emergence of patterns of antimicrobial resistance, but also to monitor the performance of the participating microbiology laboratories.
- Published
- 2003
15. Multicenter assessment of the linezolid spectrum and activity using the disk diffusion and Etest methods: report of the Zyvox® Antimicrobial Potency Study in Latin America (LA-ZAPS)
- Author
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Ballow Charles H., Biedenbach Douglas J., Rossi Flavia, and Jones Ronald N.
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Linezolid ,oxazolidinones ,antimicrobial surveillance ,resistant Gram-positive cocci ,ZAPS ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Linezolid was the first clinically applied member of the new antimicrobial class called the "oxazolidinones". These agents have a powerful spectrum of activity focussed against Gram-positive organisms including strains with documented resistances to other antimicrobial classes. We conducted a multicenter surveillance (Zyvox Antimicrobial Potency Study; ZAPS) trial of qualifying Gram-positive isolates from 24 medical centers in eight countries in Latin America. The activity and spectrum of linezolid was compared to numerous agents including glycopeptides, quinupristin/dalfopristin, b-lactams and fluoroquinolones when testing 2,640 strains by the standardized disk diffusion method or Etest (AB BIODISK, Solna, Sweden). The linezolid spectrum was complete against staphylococci (median zone diameter, 29 - 32 mm), as was the spectrum of vancomycin and quinupristin/dalfopristin. Among the enterococci, no linezolid resistance was detected, and the susceptibility rate was 93.1 - 96.4%. Only the vancomycin-susceptible Enterococcus faecium strains remained susceptible (92.8%) to quinupristin/dalfopristin. Marked differences in the glycopeptide resistance patterns (van A versus van B) were noted for the 22 isolates of VRE, thus requiring local susceptibility testing to direct therapy. Streptococcus pneumoniae and other species were very susceptible (100.0%) to linezolid, MIC90 at 0.75 mug/ml. Penicillin non-susceptible rate was 27.7% and erythromycin resistance was at 17.4%. Other streptococci were also completely susceptible to linezolid (MIC90, 1 mug/ml). These results provide the initial benchmark of potency and spectrum for linezolid in Latin American medical centers. Future comparisons should recognize that the oxazolidinones possess essentially a complete spectrum coverage of the monitored staphylococci, enterococci and streptococcal isolates in 2000-2001. This positions linezolid as the widest spectrum empiric choice against multi-resistant Gram-positive cocci, a spectrum of activity greater than available glycopeptides and the streptogramin combination.
- Published
- 2002
16. Antimicrobial activity of linezolid against Gram-positive cocci isolated in Brazil
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Sader Helio S., Gales Ana C., and Jones Ronald N.
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Gram-positive cocci ,oxazolidinones ,antimicrobial resistance ,linezolid ,vancomycin resistance ,nosocomial infections ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
The new oxazolidinone linezolid and other antimicrobial agents used to treat Gram-positive infections were tested against 1,585 Gram-positive cocci; 1,260 staphylococci and enterococci isolates from patients hospitalized in Brazilian hospitals, and 325 S. pneumoniae isolates for patients with community acquired infections. Susceptibility testing was performed using broth microdilution according to NCCLS procedures. Linezolid was the most active compound and the only drug that inhibited 100% of the isolates at the susceptible breakpoint (< 4 mg/mL). Resistance to vancomycin was very rare (99.9% susceptibility), and both quinupristin/dalfopristin and gatifloxacin were active against approximately 90% of the strains evaluated. All other compounds inhibited less than 65% of the isolates. The excellent in vitro Gram-positive activity by linezolid, in this study, indicate that this compound may represent an important therapeutic option for the treatment of infections caused by these pathogens in Brazil.
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- 2001
17. Enterococcus faecalis resistant to vancomycin and teicoplanin (VanA phenotype) isolated from a bone marrow transplanted patient in Brazil
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Cereda Rosangela F., Sader Helio S., Jones Ronald N., Sejas Lilian, Machado Antônia M., Zanatta Yara P., Rego Sinaida T. M. S., and Medeiros Eduardo A. S.
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Enterococcus faecalis ,glycopeptide resistance ,vanA ,initial case report ,transplant ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
We report for the first time in Brazil, a patient from whom an Enterococcus faecalis VanA phenotype was isolated. Glycopeptide resistance is not commonly observed in Enterococcus faecalis, so this finding is of great concern since this species is responsible for 90% of enterococcal infections in Brazil. The isolate was recovered from a surveillance rectal swab culture from a patient with acute lymphocytic leukemia (ALL). Identification to the species level was performed by conventional biochemical tests and Vitek GPI cards. Antimicrobial susceptibility testing was evaluated by use of broth microdilution and Etest (AB BIODISK, Solna, Sweden) methods. The isolate was identified as E. faecalis and was considered resistant to both vancomycin (MIC, > 256 mug/mL) and teicoplanin (MIC, 256 mug/mL). The isolate also showed high level resistance to gentamicin and streptomycin (MICs, > 1024 mug/mL), but was considered susceptible to ampicillin (MIC, 4 mug/mL). Although the frequency of enterococcal infections is very low in most Latin America countries, the finding of glycopeptide (VanA) resistance in E. faecalis increases concern about apreading antimicrobial resistance in this region.
- Published
- 2001
18. Antimicrobial susceptibility of quinupristin/dalfopristin tested against gram-positive cocci from Latin America: results from the Global SMART (GSMART) surveillance study
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Sader Helio S., Jones Ronald N., Ballow Charles H., Biedenbach Douglas J., and Cereda Rosangela F.
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Quinupristin/dalfopristin ,Gram-positive cocci ,SMART ,antimicrobial surveillance ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Gram-positive cocci are important causes of both nosocomial and community-acquired infections, and antimicrobial resistance among these pathogens has become an important problem worldwide. Since resistance among these organisms can vary substantially by geographic location, we conducted a multicenter surveillance study with isolates from five Latin American countries (15 medical centers). Quinupristin/dalfopristin (formerly RP-59500) is a novel streptogramin combination with focused activity against Gram-positive cocci, many exhibiting emerging resistance. The in vitro activity of quinupristin/dalfopristin and 12 other antimicrobial agents were evaluated against 1,948 strains including Staphylococcus aureus (747 strains), coagulase-negative staphylococci (CoNS; 446 strains), enterococci (429 strains), and various Streptococcus spp. (326 strains). Oxacillin resistance was observed in 41% of S. aureus (MIC, or = 13 mm) and 40% of CoNS (MIC, or = 18 mm). Vancomycin, teicoplanin, and quinupristin/dalfopristin (MIC90, 0.25 - 1 mug/ml) remained effective against all strains, but cross-resistance was high among other tested drugs. The quinupristin/dalfopristin MIC50 for Streptococcus pneumoniae and other streptococci was only 0.5 mug/ml (13% to 28% were penicillin-resistant; 12% to 22% were macrolide-resistant). Enterococci demonstrated variable inhibition by quinupristin/dalfopristin depending upon identification and the susceptibility testing method used. The demonstrated quinupristin/dalfopristin activity against Enterococcus faecium was confirmed, but potential species identification errors with various commercial systems continue to confuse susceptibility statistics, even though some strains of E. faecium confirmed by PCR-based or other molecular identification techniques did have quinupristin/dalfopristin MICs of > or = 4 mug/mL. Most important, glycopeptide-resistant enterococci are rapidly emerging in Latin America, and quinupristin/dalfopristin appears active against many of these isolates as well as having potency against nearly all staphylococci and streptococci tested at or = 16 mm. Comparisons to GSMART results from other continents show nearly identical quinupristin/dalfopristin activity for each Gram-positive species tested. These results define the role of quinupristin/dalfopristin in Latin American medical centers and provide a benchmark for future in vitro comparisons.
- Published
- 2001
19. Pathogen frequency and resistance patterns in Brazilian hospitals: summary of results from three years of the SENTRY antimicrobial surveillance program
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Sader Helio S., Gales Ana C., Pfaller Michael A., Mendes Rodrigo E., Zoccoli Cássia, Barth Afonso, and Jones Ronald N.
- Subjects
SENTRY ,antimicrobial resistance ,nosocomial infection ,surveillance program ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
BACKGROUND: Pathogen frequency and resistance patterns may vary significantly from country to country and also in different hospitals within a country. Thus, regional surveillance programs are essential to guide empirical therapy and infection control measures. METHODS: Rank order of occurrence and antimicrobial susceptibility of pathogenic species causing bloodstream infections (BSI), lower respiratory tract infections (LRTI), wound or skin and soft tissue infections (WSSTI), and urinary tract infections (UTI) in hospitalized patients were determined by collecting consecutive isolates over a specified period of time, as part of the SENTRY Antimicrobial Resistance Surveillance Program (SENTRY). All isolates were tested by reference broth microdilution. RESULTS AND CONCLUSIONS: A total of 3,728 bacterial strains were obtained from January, 1997, to December, 1999, from 12 Brazilian hospitals located in 4 states. The largest number of isolates were obtained from patients with BSI (2,008), followed by LRTI (822 cases), UTI (468 cases), and WSSTI (430 cases). Staphylococcus aureus was the most frequently isolated pathogen in general (22.8% - 852 isolates), followed by E. coli (13.8% - 516 cases) and Pseudomonas aeruginosa (13.3% - 496 cases). Staphylococcus aureus was also the most common species isolated from BSI (23.6%) and WSSTI (45.8%), and P. aeruginosa was the most frequent species isolated from patients with LRTI (29.4%). The main bacterial resistance problems found in this study were: imipenem resistance among P. aeruginosa (69.8% susceptibility) and Acinetobacter spp. (88.1% susceptibility); ESBL production among K. pneumoniae (48.4%) and E. coli (8.9%); resistance to third generation cephalosporins among Enterobacter spp. (68.1% susceptible to ceftazidime) and oxacillin resistance among S. aureus (34.0%) and coagulase negative staphylococci (80.1%). Only the carbapenems (88.1% to 89.3% susceptibility) showed reasonable activity against the Acinetobacter spp. isolates evaluated.
- Published
- 2001
20. Atrial septal defect: hemodynamic changes before and after closure assessed with magnetic resonance exercise imaging
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Taylor Andrew M, Jones Rod, Muthurangu Vivek, Lurz Philipp, and Schuler Pia K
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Published
- 2011
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21. Late enhancement findings in a prospective study concerning late functional outcomes following a Ross Procedure
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Bonhoeffer Philip, Cullen Shay, Walker Fiona, Derrick Graham, Lurz Philip, Nordmeyer Johannes, Muthurangu Vivek, Tsang Victor, Norman Wendy, Puranik Raj, Jones Rod, and Taylor Andrew M
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Published
- 2009
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22. Sudden unilateral visual field loss
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Jones Robin and Peall Adrian
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Branch retinal artery occlusion ,embolus ,stroke ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
We report a classical case of branch retinal artery occlusion (BRAO) in the acute setting and review the literature relating to the diagnostic, therapeutic and prognostic facets of this condition. BRAO can cause sudden visual loss and is not an infrequent presentation to emergency medical services. BRAO may indicate predisposing and related conditions capable of significant morbidity and mortality. Although current therapeutic practices in the acute setting are of uncertain benefit, conservative measures may be attempted in the emergency room by a nonophthalmologist with the aim of dislodging the causative embolus. Regardless of the current means of acute management, anitplatelet therapy and cardiovascular risk management remain the mainstay of treatment for BRAO. The potential for life-threatening systemic associations necessities investigation and multidisciplinary input.
- Published
- 2009
23. A systematic mapping review of Randomized Controlled Trials (RCTs) in care homes
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Gordon Adam L, Logan Phillipa A, Jones Rob G, Forrester-Paton Calum, Mamo Jonathan P, and Gladman John RF
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Geriatrics ,RC952-954.6 - Abstract
Abstract Background A thorough understanding of the literature generated from research in care homes is required to support evidence-based commissioning and delivery of healthcare. So far this research has not been compiled or described. We set out to describe the extent of the evidence base derived from randomized controlled trials conducted in care homes. Methods A systematic mapping review was conducted of the randomized controlled trials (RCTs) conducted in care homes. Medline was searched for “Nursing Home”, “Residential Facilities” and “Homes for the Aged”; CINAHL for “nursing homes”, “residential facilities” and “skilled nursing facilities”; AMED for “Nursing homes”, “Long term care”, “Residential facilities” and “Randomized controlled trial”; and BNI for “Nursing Homes”, “Residential Care” and “Long-term care”. Articles were classified against a keywording strategy describing: year and country of publication; randomization, stratification and blinding methodology; target of intervention; intervention and control treatments; number of subjects and/or clusters; outcome measures; and results. Results 3226 abstracts were identified and 291 articles reviewed in full. Most were recent (median age 6 years) and from the United States. A wide range of targets and interventions were identified. Studies were mostly functional (44 behaviour, 20 prescribing and 20 malnutrition studies) rather than disease-based. Over a quarter focussed on mental health. Conclusions This study is the first to collate data from all RCTs conducted in care homes and represents an important resource for those providing and commissioning healthcare for this sector. The evidence-base is rapidly developing. Several areas - influenza, falls, mobility, fractures, osteoporosis – are appropriate for systematic review. For other topics, researchers need to focus on outcome measures that can be compared and collated.
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- 2012
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24. Collaborative research between academia and industry using a large clinical trial database: a case study in Alzheimer's disease
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Jones Roy, Wilkinson David, Lopez Oscar L, Cummings Jeffrey, Waldemar Gunhild, Zhang Richard, Mackell Joan, and Gauthier Serge
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Medicine (General) ,R5-920 - Abstract
Abstract Background Large clinical trials databases, developed over the course of a comprehensive clinical trial programme, represent an invaluable resource for clinical researchers. Data mining projects sponsored by industry that use these databases, however, are often not viewed favourably in the academic medical community because of concerns that commercial, rather than scientific, goals are the primary purpose of such endeavours. Thus, there are few examples of sustained collaboration between leading academic clinical researchers and industry professionals in a large-scale data mining project. We present here a successful example of this type of collaboration in the field of dementia. Methods The Donepezil Data Repository comprised 18 randomised, controlled trials conducted between 1991 and 2005. The project team at Pfizer determined that the data mining process should be guided by a diverse group of leading Alzheimer's disease clinical researchers called the "Expert Working Group." After development of a list of potential faculty members, invitations were extended and a group of seven members was assembled. The Working Group met regularly with Eisai/Pfizer clinicians and statisticians to discuss the data, identify issues that were currently of interest in the academic and clinical communities that might lend themselves to investigation using these data, and note gaps in understanding or knowledge of Alzheimer's disease that these data could address. Leadership was provided by the Pfizer Clinical Development team leader; Working Group members rotated responsibility for being lead and co-lead for each investigation and resultant publication. Results Six manuscripts, each published in a leading subspecialty journal, resulted from the group's work. Another project resulted in poster presentations at international congresses and two were cancelled due to resource constraints. Conclusions The experience represents a particular approach to optimising the value of data mining of large clinical trial databases for the combined purpose of furthering clinical research and improving patient care. Fruitful collaboration between industry and academia was fostered while the donepezil data repository was used to advance clinical and scientific knowledge. The Expert Working Group approach warrants consideration as a blueprint for conducting similar research ventures in the future.
- Published
- 2011
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25. Evaluation of a Medical and Mental Health Unit compared with standard care for older people whose emergency admission to an acute general hospital is complicated by concurrent 'confusion': a controlled clinical trial. Acronym: TEAM: Trial of an Elderly Acute care Medical and mental health unit
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Gladman John RF, Russell Catherine, Whittamore Kathy H, Goldberg Sarah E, Harwood Rowan H, Jones Rob G, Porock Davina, Lewis Sarah A, Bradshaw Lucy E, and Elliot Rachel A
- Subjects
Medicine (General) ,R5-920 - Abstract
Abstract Background Patients with delirium and dementia admitted to general hospitals have poor outcomes, and their carers report poor experiences. We developed an acute geriatric medical ward into a specialist Medical and Mental Health Unit over an eighteen month period. Additional specialist mental health staff were employed, other staff were trained in the 'person-centred' dementia care approach, a programme of meaningful activity was devised, the environment adapted to the needs of people with cognitive impairment, and attention given to communication with family carers. We hypothesise that patients managed on this ward will have better outcomes than those receiving standard care, and that such care will be cost-effective. Methods/design We will perform a controlled clinical trial comparing in-patient management on a specialist Medical and Mental Health Unit with standard care. Study participants are patients over the age of 65, admitted as an emergency to a single general hospital, and identified on the Acute Medical Admissions Unit as being 'confused'. Sample size is 300 per group. The evaluation design has been adapted to accommodate pressures on bed management and patient flows. If beds are available on the specialist Unit, the clinical service allocates patients at random between the Unit and standard care on general or geriatric medical wards. Once admitted, randomised patients and their carers are invited to take part in a follow up study, and baseline data are collected. Quality of care and patient experience are assessed in a non-participant observer study. Outcomes are ascertained at a follow up home visit 90 days after randomisation, by a researcher blind to allocation. The primary outcome is days spent at home (for those admitted from home), or days spent in the same care home (if admitted from a care home). Secondary outcomes include mortality, institutionalisation, resource use, and scaled outcome measures, including quality of life, cognitive function, disability, behavioural and psychological symptoms, carer strain and carer satisfaction with hospital care. Analyses will comprise comparisons of process, outcomes and costs between the specialist unit and standard care treatment groups. Trial Registration number ClinicalTrials.gov: NCT01136148
- Published
- 2011
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26. Acute liver toxicity with ifosfamide in the treatment of sarcoma: a case report
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Jones Robin L, Cheung Michelle CM, and Judson Ian
- Subjects
Medicine - Abstract
Abstract Introduction Ifosfamide is a chemotherapy agent infrequently associated with liver toxicity. To the best of our knowledge, this report is the first to describe serious liver toxicity associated with ifosfamide used in combination with doxorubicin that caused acute but fully reversible liver failure and encephalopathy. This report reviews the possible mechanisms by which ifosfamide causes this adverse effect. Case report A 61-year-old Caucasian woman who presented with an inoperable right neck mass due to synovial sarcoma was treated with standard-dose ifosfamide and doxorubicin. Within 24 hours of completing the first cycle of chemotherapy, she developed significant derangements in liver function, with a 250-fold increase in transaminase and associated synthetic function impairment and encephalopathy. No other causes of liver failure were identified. Both biochemical tests and encephalopathy were reversed after supportive management and treatment with N-acetylcysteine. No liver toxicity was observed with subsequent cycles of chemotherapy with doxorubicin alone. Conclusion This case highlights the possibility that chemotherapy agents can cause rare and idiosyncratic toxicities, so physicians must be vigilant for drug reactions, especially when patients do not respond to usual treatment.
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- 2011
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27. Multi-centre parallel arm randomised controlled trial to assess the effectiveness and cost-effectiveness of a group-based cognitive behavioural approach to managing fatigue in people with multiple sclerosis
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Green Colin, Slingsby Vicky, Nock Alison, Jones Rosemary, Kersten Paula, Thomas Sarah, Thomas Peter W, Baker Roger, Galvin Kate, and Hillier Charles
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Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Fatigue is one of the most commonly reported and debilitating symptoms of multiple sclerosis (MS); approximately two-thirds of people with MS consider it to be one of their three most troubling symptoms. It may limit or prevent participation in everyday activities, work, leisure, and social pursuits, reduce psychological well-being and is one of the key precipitants of early retirement. Energy effectiveness approaches have been shown to be effective in reducing MS-fatigue, increasing self-efficacy and improving quality of life. Cognitive behavioural approaches have been found to be effective for managing fatigue in other conditions, such as chronic fatigue syndrome, and more recently, in MS. The aim of this pragmatic trial is to evaluate the clinical and cost-effectiveness of a recently developed group-based fatigue management intervention (that blends cognitive behavioural and energy effectiveness approaches) compared with current local practice. Methods/Design This is a multi-centre parallel arm block-randomised controlled trial (RCT) of a six session group-based fatigue management intervention, delivered by health professionals, compared with current local practice. 180 consenting adults with a confirmed diagnosis of MS and significant fatigue levels, recruited via secondary/primary care or newsletters/websites, will be randomised to receive the fatigue management intervention or current local practice. An economic evaluation will be undertaken alongside the trial. Primary outcomes are fatigue severity, self-efficacy and disease-specific quality of life. Secondary outcomes include fatigue impact, general quality of life, mood, activity patterns, and cost-effectiveness. Outcomes in those receiving the fatigue management intervention will be measured 1 week prior to, and 1, 4, and 12 months after the intervention (and at equivalent times in those receiving current local practice). A qualitative component will examine what aspects of the fatigue management intervention participants found helpful/unhelpful and barriers to change. Discussion This trial is the fourth stage of a research programme that has followed the Medical Research Council guidance for developing and evaluating complex interventions. What makes the intervention unique is that it blends cognitive behavioural and energy effectiveness approaches. A potential strength of the intervention is that it could be integrated into existing service delivery models as it has been designed to be delivered by staff already working with people with MS. Service users will be involved throughout this research. Trial registration Current Controlled Trials ISRCTN76517470
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- 2010
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28. Ethnicity and attitudes to deceased kidney donation: a survey in Barbados and comparison with Black Caribbean people in the United Kingdom
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Seed Paul T, Adams O Peter, Morgan Myfanwy, and Jones Roger
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Black minority ethnic groups in the UK have relatively low rates of deceased donation and report a higher prevalence of beliefs that are regarded as barriers to donation. However there is little data from migrants' countries of origin. This paper examines community attitudes to deceased kidney donation in Barbados and compares the findings with a survey conducted in a disadvantaged multi-ethnic area of south London. Methods Questionnaires were administered at four public health centres in Barbados and at three private general practices. Adjusted odds ratios were calculated to compare attitudinal responses with a prior survey of 328 Caribbean and 808 White respondents in south London. Results Questionnaires were completed by 327 respondents in Barbados (93% response); 42% men and 58% women, with a mean age of 40.4 years (SD 12.6). The main religious groups were Anglican (29%) and Pentecostal (24%). Educational levels ranged from 18% not completing 5th form to 12% with university education. Attitudes to the notion of organ donation were favourable, with 73% willing to donate their kidneys after their death and only 5% definitely against this. Most preferred an opt-in system of donation. Responses to nine attitudinal questions identified 18% as having no concerns and 9% as having 4 or more concerns. The highest level of concern (43%) was for lack of confidence that medical teams would try as hard to save the life of a person who has agreed to donate organs. There was no significant association between age, gender, education or religion and attitudinal barriers, but greater knowledge of donation had some positive effect on attitudes. Comparison of attitudes to donation in south London and Barbados (adjusting for gender, age, level of education, employment status) indicated that a significantly higher proportion of the south London Caribbean respondents identified attitudinal barriers to donation. Conclusions Community attitudes in Barbados are favourable to deceased donation based on a system of informed consent. Comparison with south London data supports the hypothesis that the relatively high prevalence of negative attitudes to deceased donation among disadvantaged ethnic minorities in high income countries may reflect feelings of marginalisation and lack of belonging.
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- 2010
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29. Kidney organ donation: developing family practice initiatives to reverse inertia
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Morgan Myfanwy, Stavroulaki Emilia, Symvoulakis Emmanouil K, and Jones Roger
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Kidney transplantation is associated with greater long term survival rates and improved quality of life compared with dialysis. Continuous growth in the number of patients with kidney failure has not been matched by an increase in the availability of kidneys for transplantation. This leads to long waiting lists, higher treatment costs and negative health outcomes. Discussion Misunderstandings, public uncertainty and issues of trust in the medical system, that limit willingness to be registered as a potential donor, could be addressed by community dissemination of information and new family practice initiatives that respond to individuals' personal beliefs and concerns regarding organ donation and transplantation. Summary Tackling both personal and public inertia on organ donation is important for any community oriented kidney donation campaign.
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- 2010
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30. Photorhabdus adhesion modification protein (Pam) binds extracellular polysaccharide and alters bacterial attachment
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Joyce Susan A, Potter Ursula J, Upadhyay Abhishek, Muñoz-Berbel Xavier, Yang Guowei, Amos Matthew R, Vlisidou Isabella, Sanchez-Contreras Maria, Jones Robert T, Ciche Todd A, Jenkins A Toby A, Bagby Stefan, ffrench-Constant Richard H, and Waterfield Nicholas R
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Microbiology ,QR1-502 - Abstract
Abstract Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C) and human (37°C) temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS)-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR) binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect through mediation of EPS properties. Despite its abundance and conservation in the genus, we find no evidence for a role of Pam in either virulence or symbiosis.
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- 2010
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31. DOMINO-AD protocol: donepezil and memantine in moderate to severe Alzheimer's disease – a multicentre RCT
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Lindesay James, Knapp Martin, Jones Roy, Johnson Tony, Jacoby Robin, Hughes Alan, Holmes Clive, Griffin Mary, Gray Richard, Findlay David, Dening Tom, Burns Alistair, Brown Richard, Bentham Peter, Barber Bob, Banerjee Sube, Ballard Clive, Adams Jessica, Baldwin Ashley, Juszczak Ed, Phillips Patrick, Sheehan Bart, Jones Rob, McKeith Ian, McShane Rupert, Macharouthu Ajay, O'Brien John, Onions Caroline, Passmore Peter, Raftery James, Ritchie Craig, and Howard Rob
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Medicine (General) ,R5-920 - Abstract
Abstract Background Alzheimer's disease (AD) is the commonest cause of dementia. Cholinesterase inhibitors, such as donepezil, are the drug class with the best evidence of efficacy, licensed for mild to moderate AD, while the glutamate antagonist memantine has been widely prescribed, often in the later stages of AD. Memantine is licensed for moderate to severe dementia in AD but is not recommended by the England and Wales National Institute for Health and Clinical Excellence. However, there is little evidence to guide clinicians as to what to prescribe as AD advances; in particular, what to do as the condition progresses from moderate to severe. Options include continuing cholinesterase inhibitors irrespective of decline, adding memantine to cholinesterase inhibitors, or prescribing memantine instead of cholinesterase inhibitors. The aim of this trial is to establish the most effective drug option for people with AD who are progressing from moderate to severe dementia despite treatment with donepezil. Method DOMINO-AD is a pragmatic, 15 centre, double-blind, randomized, placebo controlled trial. Patients with AD, currently living at home, receiving donepezil 10 mg daily, and with Standardized Mini-Mental State Examination (SMMSE) scores between 5 and 13 are being recruited. Each is randomized to one of four treatment options: continuation of donepezil with memantine placebo added; switch to memantine with donepezil placebo added; donepezil and memantine together; or donepezil placebo with memantine placebo. 800 participants are being recruited and treatment continues for one year. Primary outcome measures are cognition (SMMSE) and activities of daily living (Bristol Activities of Daily Living Scale). Secondary outcomes are non-cognitive dementia symptoms (Neuropsychiatric Inventory), health related quality of life (EQ-5D and DEMQOL-proxy), carer burden (General Health Questionnaire-12), cost effectiveness (using Client Service Receipt Inventory) and institutionalization. These outcomes are assessed at baseline, 6, 18, 30 and 52 weeks. All participants will be subsequently followed for 3 years by telephone interview to record institutionalization. Discussion There is considerable debate about the clinical and cost effectiveness of anti-dementia drugs. DOMINO-AD seeks to provide clear evidence on the best treatment strategies for those managing patients at a particularly important clinical transition point. Trial registration Current controlled trials ISRCTN49545035
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- 2009
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32. Artemisinin-naphthoquine combination (ARCO™) therapy for uncomplicated falciparum malaria in adults of Papua New Guinea: A preliminary report on safety and efficacy
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Kevau Isi, Masta Andrew, Geita Jacobed, Toraso Stephen, Jones Robert, Kuanch Cynthia, Saweri Adolf, Linge David, Hombhanje Francis W, Hiawalyer Gilbert, and Sapuri Mathias
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Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background The use of anti-malarial drug combinations with artemisinin or with one of its derivatives is now widely recommended to overcome drug resistance in falciparum as well as vivax malaria. The fixed oral dose artemisinin-naphthoquine combination (ANQ, ARCO™) is a newer artemisinin-based combination (ACT) therapy undergoing clinical assessment. A study was undertaken to assess the safety, efficacy and tolerability of ANQ combination in areas of multi-drug resistance to generate preliminary baseline data in adult population of Papua New Guinea. Methods The clinical assessment was an open-labeled, two-arm, randomized study comparing ANQ combination as a single dose regimen and three days regimen (10 mg/kg/day) of chloroquine plus single dose sulphadoxine-pyrimethamine (CQ+SP) for the treatment of uncomplicated falciparum malaria with 28 days follow-up in an adult population. The primary outcome measures for efficacy were day 1, 2, 3 7, 14 and 28-day cure rates. Secondary outcomes included parasite clearance time, fever clearance time, and gametocyte carriage. The main outcome measures for safety were incidences of post-treatment clinical and laboratory adverse events. Results Between June 2005 and July 2006, 130 patients with confirmed uncomplicated P. falciparum were randomly assigned to receive ANQ and CQ+SP, only 100 patients (51 in ANQ group and 49 in CQ+SP group) were evaluated for clinical and parasitological outcomes. All the patients treated with ANQ and CQ+SP showed adequate clinical and parasitological response with 28 days follow-up. The cure rate for ANQ on day 1, 2, 3, 7, 14, and 28 was 47%, 86%, 92%, 94%, 94% and 94%, respectively. Recrudescence account for 6%; all were cleared on day 21. For CQ+SP treated group the cure rates were 24%, 67%, 82%, 82%, 84% and 88%, respectively. Recrudescence accounted for 10%; all were cleared on day 28 except for one patient. Both regimens were well tolerated with no serious adverse events. The proportion of gametocyte carriers was higher in CQ+SP treated group than ANQ treatment (41% versus 12%; p < 0.05). Conclusion While these data are not themselves sufficient, it strongly suggests that the ANQ combination as a single dose administration is safe and effective for the treatment of uncomplicated P. falciparum malaria in the adult population of Papua New Guinea and deserves further clinical evaluation.
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- 2009
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33. Attitudes to kidney donation among primary care patients in rural Crete, Greece
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Chatziarsenis Marios, Tsafantakis Emmanouil, Alegakis Athanasios, Morgan Myfanwy, Antonakis Nikos, Komninos Ioannis D, Symvoulakis Emmanouil K, Philalithis Anastas, and Jones Roger
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background In Greece, there is limited research on issues related to organ donation, and the low rate of registration as donors requires explanation. This study reports the findings of a survey of knowledge and attitudes to kidney donation among primary care patients in rural Crete, Greece. Methods Two rural primary care settings in the island of Crete, Anogia Health Centre and Vrachasi Practice, were involved in a questionnaire survey. This was conducted among primary care patients (aged 18 years and over) with routine appointments, to assess their knowledge and attitudes to kidney donation. General practitioners (GPs) recruited patients and questionnaires were completed following the patients' medical consultation. Pearson's chi square tests were used and crude odds ratios (OR) with 95% confidence intervals (95% CI) were calculated in order to investigate into the possible associations between the respondents' knowledge, attitudes and specific concerns in relation to their socio-demographic features. Logistic regression analyses were used to examine differences by geographical location. Results The 224 (92.5%) of the 242 primary care attenders who were approached agreed to participate. Only 2.2% (5/224) of the respondents carried a donor card. Most participants (84.4%, 189/224) did not feel well informed about registering as a kidney donor. More than half of the respondents (54.3%, 121/223) were unwilling to register as a kidney donor and donate kidneys for transplant after death. Over a third of respondents (35.4%, 79/223) were not confident that medical teams would try as hard as possible to save the life of a person who has agreed to donate organs. People with a higher level of education were more likely to be willing to register as kidney donors [(OR: 3.3; 95% CI: 1.8–6.0), p < 0.001)] and to be less worried about their kidneys being removed after death [(OR: 0.3; 95% CI: 0.1–0.5), p < 0.001)] than those having a lower level of education. Conclusion Lack of knowledge and information regarding organ donation and negative attitudes related to registration as donors were the main findings of this study. Efforts should be based on targeting the attitudes to organ donation of individuals and population groups.
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- 2009
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34. The external validity of published randomized controlled trials in primary care
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Montgomery Alan A, McCowan Colin, Jones Robert O, Jones Ritu, and Fahey Tom
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Medicine (General) ,R5-920 - Abstract
Abstract Background A criticism of Randomized Controlled Trials (RCTs) in primary care is that they lack external validity, participants being unrepresentative of the wider population. Our aim was to determine whether published primary care-based RCTs report information about how the study sample is assembled, and whether this is associated with RCT characteristics. Methods We reviewed RCTs published in four primary care journals in the years 2001–2004. Main outcomes were: (1) eligibility fraction (proportion eligible of those screened), (2) enrolment fraction (proportion randomised of those eligible), (3) recruitment fraction (proportion of potential participants actually randomised), and (4) number of patients needed to be screened (NNS) in order to randomize one participant. Results A total of 148 RCTs were reviewed. One hundred and three trials (70%) reported the number of individuals assessed by investigators for eligibility, 119 (80%) reported the number eligible for participation, and all reported the actual number recruited. The median eligibility fraction was 83% (IQR 40% to 100%), and the median enrolment fraction was 74% (IQR 49% to 92%). The median NNS was 2.43, with some trials reportedly recruiting every patient or practice screened for eligibility, and one trial screening 484 for each patient recruited. We found no association between NNS and journal, trial size, multi- or single-centre, funding source or type of intervention. There may be associations between provision of sufficient recruitment data for the calculation of NNS and funding source and type of intervention. Conclusion RCTs reporting recruitment data in primary care suggest that once screened for eligibility and found to match inclusion criteria patients are likely to be randomized. This finding needs to be treated with caution as it may represent inadequate identification or reporting of the eligible population. A substantial minority of RCTs did not provide sufficient information about the patient recruitment process.
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- 2009
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35. High-throughput single nucleotide polymorphism genotyping using nanofluidic Dynamic Arrays
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Crenshaw Andrew, Hutchinson Amy, Hicks Belynda, Yeager Meredith, Berndt Sonja, Huang Wen-Yi, Hayes Richard, Chanock Stephen, Wang Jun, Lin Min, Jones Robert, and Ramakrishnan Ramesh
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Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Single nucleotide polymorphisms (SNPs) have emerged as the genetic marker of choice for mapping disease loci and candidate gene association studies, because of their high density and relatively even distribution in the human genomes. There is a need for systems allowing medium multiplexing (ten to hundreds of SNPs) with high throughput, which can efficiently and cost-effectively generate genotypes for a very large sample set (thousands of individuals). Methods that are flexible, fast, accurate and cost-effective are urgently needed. This is also important for those who work on high throughput genotyping in non-model systems where off-the-shelf assays are not available and a flexible platform is needed. Results We demonstrate the use of a nanofluidic Integrated Fluidic Circuit (IFC) - based genotyping system for medium-throughput multiplexing known as the Dynamic Array, by genotyping 994 individual human DNA samples on 47 different SNP assays, using nanoliter volumes of reagents. Call rates of greater than 99.5% and call accuracies of greater than 99.8% were achieved from our study, which demonstrates that this is a formidable genotyping platform. The experimental set up is very simple, with a time-to-result for each sample of about 3 hours. Conclusion Our results demonstrate that the Dynamic Array is an excellent genotyping system for medium-throughput multiplexing (30-300 SNPs), which is simple to use and combines rapid throughput with excellent call rates, high concordance and low cost. The exceptional call rates and call accuracy obtained may be of particular interest to those working on validation and replication of genome- wide- association (GWA) studies.
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- 2009
36. Exposing the key functions of a complex intervention for shared care in mental health: case study of a process evaluation
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Redfern Sally, Norman Ian, Byng Richard, and Jones Roger
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Complex interventions have components which can vary in different contexts. Using the Realistic Evaluation framework, this study investigates how a complex health services intervention led to developments in shared care for people with long-term mental illness. Methods A retrospective qualitative interview study was carried out alongside a randomised controlled trial. The multi-faceted intervention supported by facilitators aimed to develop systems for shared care. The study was set in London. Participants included 46 practitioners and managers from 12 participating primary health care teams and their associated community mental health teams. Interviews focussed on how and why out comes were achieved, and were analysed using a framework incorporating context and intervening mechanisms. Results Thirty-one interviews were completed to create 12 case studies. The enquiry highlighted the importance of the catalysing, doing and reviewing functions of the facilitation process. Other facets of the intervention were less dominant. The intervention catalysed the allocation of link workers and liaison arrangements in nearly all practices. Case discussions between link workers and GPs improved individual care as well as helping link workers become part of the primary care team; but sustained integration into the team depended both on flexibility and experience of the link worker, and upon selection of relevant patients for the case discussions. The doing function of facilitators included advice and, at times, manpower, to help introduce successful systems for reviewing care, however time spent developing IT systems was rarely productive. The reviewing function of the intervention was weak and sometimes failed to solve problems in the development of liaison or recall. Conclusion Case discussions and improved liaison at times of crisis, rather than for proactive recall, were the key functions of shared care contributing to the success of Mental Health Link. This multifaceted intervention had most impact through catalysing and doing, whereas the reviewing function of the facilitation was weak, and other components were seen as less important. Realistic Evaluation provided a useful theoretical framework for this process evaluation, by allowing a specific focus on context. Although complex interventions might appear 'out of control', due to their varied manifestation in different situations, context sensitive process evaluations can help identify the intervention's key functions.
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- 2008
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37. A rare case of a retroperitoneal enterogenous cyst with in-situ adenocarcinoma
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Woodland James G, de Sanctis Stefano, Karanjia Nariman D, Jones Robin L, Lordan Jeffrey T, Middleton Gary, and Menezes Neville
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Surgery ,RD1-811 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Retroperitoneal enterogenous cysts are uncommon and adenocarcinoma within such cysts is a rare complication. Case presentation We present the third described case of a retroperitoneal enterogenous cyst with adenocarcinomatous changes and only the second reported case whereby the cyst was not arising from any anatomical structure. Conclusion This case demonstrates the difficulties in making a diagnosis as well as the importance of a multi-disciplinary approach, and raises further questions regarding post-operative treatment with chemotherapy.
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- 2007
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38. Daptomycin antimicrobial activity tested against methicillin-resistant staphylococci and vancomycin-resistant enterococci isolated in European medical centers (2005)
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Watters Amy A, Sader Helio S, Fritsche Thomas R, and Jones Ronald N
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Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Daptomycin is a cyclic lipopeptide with potent activity and broad spectrum against Gram-positive bacteria currently used for the treatment of complicated skin and skin structure infections and bacteremia, including right sided endocarditis. We evaluated the in vitro activity of this compound and selected comparator agents tested against clinical strains of staphylococci and enterococci collected in European medical centers in 2005. Methods A total of 4,640 strains from 23 medical centers located in 10 European countries, Turkey and Israel (SENTRY Program platform) were tested for susceptibility by reference broth microdilution methods according to Clinical and Laboratory Standards Institute guidelines and interpretative criteria. Mueller-Hinton broth was supplemented to 50 mg/L Ca++ for testing daptomycin. Results for oxacillin (methicillin)-resistant staphylococci and vancomycin-resistant enterococci were analyzed separately. Results Oxacillin resistance rates among Staphylococcus aureus varied from 2.1% in Sweden to 42.5% in the United Kingdom (UK) and 54.7% in Ireland (29.1% overall), while vancomycin resistance rates varied from 0.0% in France, Sweden and Switzerland to 66.7% in the UK and 71.4% in Ireland among Enterococcus faecium (17.9% overall). All S. aureus strains were inhibited at daptomycin MIC of 1 mg/L (MIC50/90, 0.25/0.5 mg/L; 100.0% susceptible) and only one coagulase-negative staphylococci strain (0.1%) showed an elevated (>1 mg/L) daptomycin MIC value (4 mg/L). Among E. faecalis (MIC50/90, 0.5/1 mg/L; 100% susceptible) the highest daptomycin MIC value was 2 mg/L; while among E. faecium (MIC50/90, 2/4 mg/L; 100% susceptible) the highest MIC result was 4 mg/L. Conclusion Daptomycin showed excellent in vitro activity against staphylococci and enterococci collected in European medical centers in 2005 and resistance to oxacillin, vancomycin or quinupristin/dalfopristin did not compromise its activity overall against these pathogens. Based on these results and those of previous publications, daptomycin appears to be an excellent therapeutic option for serious infections caused by oxacillin-resistant staphylococci and vancomycin-resistant enterococci in Europe.
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- 2007
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39. Correlation of central auditory processing deficits and vascular loop syndrome.
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Shinn JB, Bush ML, and Jones RO
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We report a case involving a 49-year-old woman with vascular loop syndrome. The patient was evaluated because of complaints of decreased hearing sensitivity in her right ear. Central auditory tests were performed. The patient was found to have an asymmetry on pure-tone audiometry and an auditory processing deficit, suggesting central pathology. Magnetic resonance imaging confirmed central involvement, revealing a vascular loop extending into the right internal auditory canal. This case report demonstrates that auditory deficits may result from vascular loop compression and that these deficits may benefit from a battery of tests to help identify and localize the pathology. [ABSTRACT FROM AUTHOR]
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- 2009
40. Chemical bonding in phase-change chalcogenides.
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Müller PC, Elliott SR, Dronskowski R, and Jones RO
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Almost all phase-change memory materials (PCM) contain chalcogen atoms, and their chemical bonds have been denoted both as 'electron-deficient' [sometimes referred to as 'metavalent'] and 'electron-rich' ['hypervalent', multicentre]. The latter involve lone-pair electrons. We have performed calculations that can discriminate unambiguously between these two classes of bond and have shown that PCM have electron-rich, 3c-4e ('hypervalent') bonds. Plots of charge transferred between ( ET ) and shared with ( ES ) neighbouring atoms cannot on their own distinguish between 'metavalent' and 'hypervalent' bonds, both of which involve single-electron bonds. PCM do not exhibit 'metavalent' bonding and are not electron-deficient; the bonding is electron-rich of the 'hypervalent' or multicentre type., (Creative Commons Attribution license.)
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- 2024
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41. Defining optimal thresholds for digital Brix refractometry to determine IgG concentration in ewe colostrum and lamb serum in Scottish lowland sheep flocks.
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Hamer K, Bellingham M, Evans NP, Jones RO, and Denholm KS
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- Pregnancy, Animals, Sheep, Female, Immunoglobulin G, Refractometry veterinary, Scotland, Animals, Newborn, Colostrum, Body Fluids
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This research aimed to define thresholds for ewe colostrum and lamb serum Brix refractometer measurements in lowland Scottish sheep. This would facilitate the use of this convenient, sheep-side test, enabling quick and accurate identification of poor quality colostrum and prevention of failure of transfer of passive immunity (FTPI) in lambs. Secondary aims were to identify risk factors for poor colostrum quality and FTPI in lambs. Serum samples (n = 233) were collected from lambs between 24 and 48hrs after birth, from four lowland Scottish meat sheep farms. Pre-suckle colostrum samples (n = 112) were also collected from ewes on two of these farms. Farmers provided information on litter size, ewe body condition score, ewe breed and dystocia. Duplicate digital Brix refractometer measurements were compared with immunoglobulin G (IgG) radial immunodiffusion (RID) testing for all colostrum and serum samples. Receiver operating characteristic (ROC) curves were used to redefine thresholds for Brix testing in colostrum and serum. Linear regression models were constructed with colostrum and serum IgG concentration as the outcomes of interest. Colostrum and serum IgG concentrations were highly variable. The prevalence of inadequate colostrum quality (using <50 g/L IgG on RID) was 4.5% (95% CI = 1.5 - 10.1) and the prevalence of FTPI (using <15 g/L IgG in serum on RID) was 7.73% (95% CI = 4.64-11.93). A ewe's colostrum IgG concentration was significantly and positively associated with the serum IgG concentration of her lamb(s) (p = 0.02). ROC analysis defined a Brix threshold for adequate colostrum quality of > 22.10% (sensitivity 80% (95%CI=28.4-99.5), specificity 90% (95%CI=82.3-94.8)). ROC analysis defined a Brix threshold for serum of > 8.65% for adequate passive transfer of immunity in Scottish lambs (sensitivity 94% (95%CI=72.7-99.8), specificity 82% (95%CI=76.6-87.2)). To optimise passive transfer of immunity in lambs, we suggest that ewe colostrum Brix measurements be defined as 'poor' (<22%); 'fair' (22-26%) and 'good' (>26%); and lamb serum as 'poor' (<8%); 'fair' (8-9%) and 'good' (>9%). It is recommended that these tests are used as for flock screening, using samples from multiple animals., Competing Interests: Declaration of Competing Interest Funding was provided by the Ruminant Bursary from MSD Animal Health Ltd. The funders were not involved in study design, data collection, data interpretation or publication. None of the authors has any other financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2023
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42. Quantitative TMT-based proteomics revealing host, dietary and microbial proteins in bovine faeces including barley serpin Z4, a prominent component in the head of beer.
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Huang Y, Jonsson NN, McLaughlin M, Burchmore R, Johnson PCD, Jones RO, McGill S, Brady N, Weidt S, and Eckersall PD
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- Cattle, Animals, Proteome analysis, Beer analysis, Proteomics, Tandem Mass Spectrometry, Diet veterinary, Feces microbiology, Bacteria, Plant Extracts, Animal Feed analysis, Hordeum, Serpins analysis, Archaeal Proteins
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There has been little information about the proteome of bovine faeces or about the contribution to the faecal proteome of proteins from the host, the feed or the intestinal microbiome. Here, the bovine faecal proteome and the origin of its component proteins was assessed, while also determining the effect of treating barley, the major carbohydrate in the feed, with either ammonia (ATB) or sodium propionate (PTB) preservative. Healthy continental crossbreed steers were allocated to two groups and fed on either of the barley-based diets. Five faecal samples from each group were collected on Day 81 of the trial and analysed by quantitative proteomics using nLC-ESI-MS/MS after tandem mass tag labelling. In total, 281 bovine proteins, 199 barley proteins, 176 bacterial proteins and 190 archaeal proteins were identified in the faeces. Mucosal pentraxin, albumin and digestive enzymes were among bovine proteins identified. Serpin Z4 a protease inhibitor was the most abundant barley protein identified which is also found in barley-based beer, while numerous microbial proteins were identified, many originating bacteria from Clostridium, while Methanobrevibacter was the dominant archaeal genus. Thirty-nine proteins were differentially abundant between groups, the majority being more abundant in the PTB group compared to the ATB group. SIGNIFICANCE: Proteomic examination of faeces is becoming a valuable means to assess the health of the gastro-intestinal tract in several species, but knowledge on the proteins present in bovine faeces is limited. This investigation aimed to characterise the proteome of bovine faecal extracts in order to evaluate the potential for investigations of the proteome as a means to assess the health, disease and welfare of cattle in the future. The investigation was able to identify proteins in bovine faeces that had been (i) produced by the individual cattle, (ii) present in the barley-based feed eaten by the cattle or (iii) produced by bacteria and other microbes in the rumen or intestines. Bovine proteins identified included mucosal pentraxin, serum albumin and a variety of digestive enzymes. Barley proteins found in the faeces included serpin Z4, a protease inhibitor that is also found in beer having survived the brewing process. Bacterial and archaeal proteins in the faecal extracts were related to several pathways related to the metabolism of carbohydrates. The recognition of the range of proteins that can be identified in bovine faeces raises the possibility that non-invasive sample collection of this material could provide a novel diagnostic approach to cattle health and welfare., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023. Published by Elsevier B.V.)
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- 2023
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43. The Myth of "Metavalency" in Phase-Change Materials.
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Jones RO, Elliott SR, and Dronskowski R
- Abstract
Phase-change memory materials (PCMs) have unusual properties and important applications, and recent efforts to find improved materials have focused on their bonding mechanisms. "Metavalent bonding" or "metavalency," intermediate between "metallic" and "covalent" bonding and comprising single-electron bonds, has been proposed as a fundamentally new mechanism that is relevant both here and for halide perovskite materials. However, it is shown that PCMs, which violate the octet rule, have two types of covalent bond: two-center, two-electron (2c-2e) bonds, and electron-rich, multicenter bonds (3c-4e bonds, hyperbonds) involving lone-pair electrons. The latter have bond orders less than one and are examples of the century-old concept of "partial" bonds., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)
- Published
- 2023
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44. DFT exchange: sharing perspectives on the workhorse of quantum chemistry and materials science.
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Teale AM, Helgaker T, Savin A, Adamo C, Aradi B, Arbuznikov AV, Ayers PW, Baerends EJ, Barone V, Calaminici P, Cancès E, Carter EA, Chattaraj PK, Chermette H, Ciofini I, Crawford TD, De Proft F, Dobson JF, Draxl C, Frauenheim T, Fromager E, Fuentealba P, Gagliardi L, Galli G, Gao J, Geerlings P, Gidopoulos N, Gill PMW, Gori-Giorgi P, Görling A, Gould T, Grimme S, Gritsenko O, Jensen HJA, Johnson ER, Jones RO, Kaupp M, Köster AM, Kronik L, Krylov AI, Kvaal S, Laestadius A, Levy M, Lewin M, Liu S, Loos PF, Maitra NT, Neese F, Perdew JP, Pernal K, Pernot P, Piecuch P, Rebolini E, Reining L, Romaniello P, Ruzsinszky A, Salahub DR, Scheffler M, Schwerdtfeger P, Staroverov VN, Sun J, Tellgren E, Tozer DJ, Trickey SB, Ullrich CA, Vela A, Vignale G, Wesolowski TA, Xu X, and Yang W
- Subjects
- Humans, Materials Science
- Abstract
In this paper, the history, present status, and future of density-functional theory (DFT) is informally reviewed and discussed by 70 workers in the field, including molecular scientists, materials scientists, method developers and practitioners. The format of the paper is that of a roundtable discussion, in which the participants express and exchange views on DFT in the form of 302 individual contributions, formulated as responses to a preset list of 26 questions. Supported by a bibliography of 777 entries, the paper represents a broad snapshot of DFT, anno 2022.
- Published
- 2022
- Full Text
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45. National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK.
- Author
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Nolan GS, Dunne JA, Lee AE, Wade RG, Kiely AL, Pritchard Jones RO, Gardiner MD, and Jain A
- Subjects
- Humans, United Kingdom, Carcinoma, Basal Cell surgery, Plastic Surgery Procedures, Skin Neoplasms surgery, Surgery, Plastic
- Published
- 2022
- Full Text
- View/download PDF
46. MicroRNA and metabolomics signatures for adrenomyeloneuropathy disease severity.
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Turk BR, Poisson LM, Nemeth CL, Goodman J, Moser AB, Jones RO, Fatemi A, and Singh J
- Abstract
Adrenomyeloneuropathy (AMN), the slow progressive phenotype of adrenoleukodystrophy (ALD), has no clinical plasma biomarker for disease progression. This feasibility study aimed to determine whether metabolomics and micro-RNA in blood plasma provide a potential source of biomarkers for AMN disease severity. Metabolomics and RNA-seq were performed on AMN and healthy human blood plasma. Biomarker discovery and pathway analyses were performed using clustering, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and regression against patient's clinical Expanded Disability Status Score (EDSS). Fourteen AMN and six healthy control samples were analyzed. AMN showed strong disease-severity-specific metabolic and miRNA clustering signatures. Strong, significant clinical correlations were shown for 7-alpha-hydroxy-3-oxo-4-cholestenoate (7-HOCA) ( r
2 = 0.83, p < 0.00001), dehydroepiandrosterone sulfate (DHEA-S; r2 = 0.82, p < 0.00001), hypoxanthine ( r2 = 0.82, p < 0.00001), as well as miRNA-432-5p ( r2 = 0.68, p < 0.00001). KEGG pathway comparison of mild versus severe disease identified affected downstream systems: GAREM, IGF-1, CALCRL, SMAD2&3, glutathione peroxidase, LDH, and NOS. This feasibility study demonstrates that miRNA and metabolomics are a source of potential plasma biomarkers for disease severity in AMN, providing both a disease signature and individual markers with strong clinical correlations. Network analyses of affected systems implicate differentially altered vascular, inflammatory, and oxidative stress pathways, suggesting disease-severity-specific mechanisms as a function of disease severity., Competing Interests: Potential competing interest for Ali Fatemi: Paid member of drug safety monitoring board – Bluebird Bio, Co‐inventor of Compositions and methods for treatment of peroxisomal disorders and leukodystrophies, Patent #US20170119899A1. Potential competing interest for Bela Rui Turk: Co‐inventor of Compositions and methods for treatment of peroxisomal disorders and leukodystrophies, Patent #US20170119899A1. Laila Marie Poisson, Christina Linnea Nemeth, Jordan Goodman, Richard Owen Jones, and Jordan Goodman have no relevant potential competing interests to report., (© 2022 The Authors. JIMD Reports published by John Wiley & Sons Ltd on behalf of SSIEM.)- Published
- 2022
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47. The chemical bond in solids-revisited.
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Jones RO
- Abstract
This article complements an earlier topical review of the chemical bond (Jones 2018 J. Phys.: Condens. Matter 30 153001), starting in the mid-19th century and seen from the perspective of a condensed matter physicist. The discussion of applications focused on the structure and properties of phase change materials. We review here additional aspects of chemistry, particularly some that have raised interest recently in this context. Concepts such as 'electron-rich', 'electron-deficient (excess orbital)', 'hypervalent', 'three-centre', and 'metavalent' bonds, and 'multicentre hyperbonding' are now found in the condensed matter literature. They are surveyed here, as well as the bond in metals and the 'Peierls' distortion. What are these concepts, are they related, and are they sometimes new labels for established, but unfamiliar ideas? 'Half bonds' and 'fractional valencies' play a central role in this discussion. It is remarkable that they were introduced 100 years ago, but ignored or forgotten, and have needed to be rediscovered more than once., (Creative Commons Attribution license.)
- Published
- 2022
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48. Spatial and temporal analysis of sheep scab notifications in Scotland, 2014-2019.
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Jones RO, Geddes E, Mohr S, Bell IR, Brulisauer AG, Pritchard C, Nisbet AJ, Burgess STG, and Busin V
- Subjects
- Animals, Disease Outbreaks veterinary, Scotland epidemiology, Sheep, Ectoparasitic Infestations epidemiology, Ectoparasitic Infestations veterinary, Mite Infestations epidemiology, Mite Infestations veterinary, Sheep Diseases epidemiology
- Abstract
Background: Sheep scab is considered an endemic disease of great welfare and economic significance in the UK., Method: This paper provides an up-to-date assessment of the impact of Sheep Scab (Scotland) Order 2010 on sheep scab notifications in Scotland between 1 January 2014 and 31 December 2019, using data collected by the APHA., Results: In total, 564 sheep scab notifications were reported from 503 unique holdings, of which 44 holdings (8.7%) reported more than one incident. The number of notifications did not differ between years, with 81, 84, 93, 101, 109 and 97 notifications recorded in 2014, 2015, 2016, 2017, 2018 and 2019, respectively: representing an average annual notification prevalence of 0.63% (1/159 flocks/year). A total of 413/564 records documented how notifications were resolved, with macrocyclic lactone and organophosphate treatments accounting for 79.6% and 20.4% of resolutions, respectively., Conclusion: Our results suggest that the Order has facilitated the notification of sheep scab in Scotland (including trends and preferred methods of resolution), allowed industry and government to identify previously unidentified potentially free areas as well as recurrent incidents on sheep farms, and start to understand better the geographical and temporal nature of scab outbreaks. However, concerns remain about a potential lack of engagement, evidenced by the low notification prevalence and stagnant annual notification rates., (© 2022 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)
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- 2022
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49. Interannual climate variability mediates changes in carbon and nitrogen pools caused by annual grass invasion in a semiarid shrubland.
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Mahood AL, Jones RO, Board DI, Balch JK, and Chambers JC
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- Ecosystem, Introduced Species, Nitrogen, Soil, Carbon, Poaceae
- Abstract
Exotic plant invasions alter ecosystem properties and threaten ecosystem functions globally. Interannual climate variability (ICV) influences both plant community composition (PCC) and soil properties, and interactions between ICV and PCC may influence nitrogen (N) and carbon (C) pools. We asked how ICV and non-native annual grass invasion covary to influence soil and plant N and C in a semiarid shrubland undergoing widespread ecosystem transformation due to invasions and altered fire regimes. We sampled four progressive stages of annual grass invasion at 20 sites across a large (25,000 km
2 ) landscape for plant community composition, plant tissue N and C, and soil total N and C in 2013 and 2016, which followed 2 years of dry and wet conditions, respectively. Multivariate analyses and ANOVAs showed that in invasion stages where native shrub and perennial grass and forb communities were replaced by annual grass-dominated communities, the ecosystem lost more soil N and C in wet years. Path analysis showed that high water availability led to higher herbaceous cover in all invasion stages. In stages with native shrubs and perennial grasses, higher perennial grass cover was associated with increased soil C and N, while in annual-dominated stages, higher annual grass cover was associated with losses of soil C and N. Also, soil total C and C:N ratios were more homogeneous in annual-dominated invasion stages as indicated by within-site standard deviations. Loss of native shrubs and perennial grasses and forbs coupled with annual grass invasion may lead to long-term declines in soil N and C and hamper restoration efforts. Restoration strategies that use innovative techniques and novel species to address increasing temperatures and ICV and emphasize maintaining plant community structure-shrubs, grasses, and forbs-will allow sagebrush ecosystems to maintain C sequestration, soil fertility, and soil heterogeneity., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)- Published
- 2022
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50. Melt-quenched and as-deposited structures of amorphous selenium: a density functional/ molecular dynamics comparison.
- Author
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Kalikka J, Konstantinou K, Akola J, and Jones RO
- Abstract
Molecular dynamics simulations using a density functional description of energies and forces have been carried out for a model of an as-deposited (AD) surface of amorphous selenium. The deposition model assumed the annealing (at 400 K) of layers of randomly located single atoms, followed by compression to the density used in earlier melt-quenched (MQ) simulations of amorphous Se, and by further annealing. The AD and MQ structures are predominantly twofold coordinated and similar, for example in the pair distribution functions, with notable differences: the AD structures have more defects (atoms with one and three neighbours), and the ring distributions differ. These differences are also reflected in the electronic structures of the AD and MQ samples, where the increased presence of defects in the former influences the Bader charges and the edge states of the band gap. The dominance of rings found in a previous simulation of AD structures is not found., (Creative Commons Attribution license.)
- Published
- 2021
- Full Text
- View/download PDF
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