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Holmes J, Roberts G, Geen J, Dodd A, Selby NM, Lewington A, Scholey G, Williams JD, Phillips AO. Utility of electronic AKI alerts in intensive care: A national multicentre cohort study. J Crit Care 2017; 44:185-190. [PMID: 29145061 DOI: 10.1016/j.jcrc.2017.10.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 09/27/2017] [Accepted: 10/17/2017] [Indexed: 01/20/2023]
Abstract
BACKGROUND Electronic AKI alerts highlight changes in serum creatinine compared to the patient's own baseline. Our aim was to identify all AKI alerts and describe the relationship between electronic AKI alerts and outcome for AKI treated in the Intensive Care Unit (ICU) in a national multicentre cohort. METHODS A prospective cohort study was undertaken between November 2013 and April 2016, collecting data on electronic AKI alerts issued. RESULTS 10% of 47,090 incident AKI alerts were associated with ICU admission. 90-day mortality was 38.2%. Within the ICU cohort 48.8% alerted in ICU. 51.2% were transferred to ICU within 7days of the alert, of which 37.8% alerted in a hospital setting (HA-AKI) and 62.2% in a community setting (CA-AKI). Mortality was higher in patients transferred to ICU following the alert compared to those who had an incident alert on the ICU (p<0.001), and was higher in HA-AKI (45.3%) compared to CA-AKI (39.5%) (35.0%, p=0.01). In the surviving patients, the proportion of patient recovering renal function following, was significantly higher in HA-AKI alerting (84.2%, p=0.004) and CA-AKI alerting patients (87.6%, p<0.001) compared to patients alerting on the ICU (78.3%). CONCLUSION The study provides a nationwide characterisation of AKI in ICU highlighting the high incidence and its impact on patient outcome. The data also suggests that within the cohort of AKI patients treated in the ICU there are significant differences in the presentation and outcome between those patients that require transfer to the ICU after AKI is identified and those who develop AKI following ICU admission. Moreover, the study demonstrates that using AKI e-alerts provides a centralised resource which does not rely on clinical diagnosis of AKI or coding, resulting in a robust data set which can be used to define the incidence and outcome of AKI in the ICU setting.
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Phillips D, Young O, Holmes J, Allen LA, Roberts G, Geen J, Williams JD, Phillips AO. Seasonal pattern of incidence and outcome of Acute Kidney Injury: A national study of Welsh AKI electronic alerts. Int J Clin Pract 2017; 71. [PMID: 28869717 DOI: 10.1111/ijcp.13000] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 08/08/2017] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVES To identify any seasonal variation in the occurrence of, and outcome following Acute Kidney Injury. METHODS The study utilised the biochemistry based AKI electronic (e)-alert system established across the Welsh National Health Service to collect data on all AKI episodes to identify changes in incidence and outcome over one calendar year (1st October 2015 and the 30th September 2016). RESULTS There were total of 48 457 incident AKI alerts. The highest proportion of AKI episodes was seen in the quarter of January to March (26.2%), and the lowest in the quarter of October to December (23.3%, P < .001). The same trend was seen for both community-acquired and hospital-acquired AKI sub-sets. Overall 90 day mortality for all AKI was 27.3%. In contrast with the seasonal trend in AKI occurrence, 90 day mortality after the incident AKI alert was significantly higher in the quarters of January to March and October to December compared with the quarters of April to June and July to September (P < .001) consistent with excess winter mortality reported for likely underlying diseases which precipitate AKI. CONCLUSIONS In summary we report for the first time in a large national cohort, a seasonal variation in the incidence and outcomes of AKI. The results demonstrate distinct trends in the incidence and outcome of AKI.
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Holmes J, Allen N, Roberts G, Geen J, Williams JD, Phillips AO. Acute kidney injury electronic alerts in primary care - findings from a large population cohort. QJM 2017; 110:577-582. [PMID: 28402560 DOI: 10.1093/qjmed/hcx080] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Electronic reporting of AKI has been used to aid early AKI recognition although its relevance to CA-AKI and primary care has not been described. AIMS We described the characteristics and clinical outcomes of patients with CA-AKI, and AKI identified in primary care (PC-AKI) through AKI e-Alerts. DESIGN A prospective national cohort study was undertaken to collect data on all e-alerts representing adult CA-AKI. METHOD The study utilized the biochemistry based AKI electronic (e)-alert system that is established across the Welsh National Health Service. RESULTS 28.8% of the 22 723 CA-AKI e-alerts were classified as PC-AKI. Ninety-day mortality was 24.0% and lower for PC-AKI vs. non-primary care (non-PC) CA-AKI. Hospitalization was 22.3% for PC-AKI and associated with greater disease severity, higher mortality, but better renal outcomes (non-recovery: 18.1% vs. 21.6%; progression of pre-existing CKD: 40.5% vs. 58.3%). 49.1% of PC-AKI had a repeat test within 7 days, 42.5% between 7 and 90 days, and 8.4% was not repeated within 90 days. There was significantly more non-recovery (24.0% vs. 17.9%) and progression of pre-existing CKD (63.3% vs. 47.0%) in patients with late repeated measurement of renal function compared to those with early repeated measurement of renal function. CONCLUSION The data demonstrate the clinical utility of AKI e-alerts in primary care. We recommend that a clinical review, or referral together with a repeat measurement of renal function within 7 days should be considered an appropriate response to AKI e-alerts in primary care.
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Williams JD, Wischmeyer PE. Assessment of perioperative nutrition practices and attitudes-A national survey of colorectal and GI surgical oncology programs. Am J Surg 2017; 213:1010-1018. [PMID: 27889271 PMCID: PMC6814259 DOI: 10.1016/j.amjsurg.2016.10.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 10/01/2016] [Accepted: 10/24/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND Implementation of evidence-based peri-operative nutrition in the U.S. is poorly described and hypothesized to be suboptimal. This study broadly describes practices and attitudes regarding nutrition screening/intervention in U.S. gastrointestinal and oncologic surgeons. METHODS Nationwide nutritional practice survey of GI/Oncologic surgical faculty. RESULTS Program response rates were 57% and 81% for colorectal and oncology fellowships, respectively. Only 38% had formal nutritional screening processes in place. Average estimated percent of patients malnourished, receiving nutritional screening, and receiving nutritional supplementation preoperatively were 28%, 43%, and 21%, respectively. University-affiliation (p = 0.0371) and a formal screening process (p = 0.0312) predicted higher preoperative nutritional screening rates. Controversy existed regarding routine use of perioperative immunonutrition, but strong consensus emerged that lack of awareness regarding positive data for immunonutrition impedes usage. CONCLUSION U.S. surgeons recognize importance of perioperative nutritional screening and benefits of basic nutrition therapy. However, limited formal nutrition screening programs currently exist indicating a significant need for implementation of nutrition screening and basic nutrition intervention. Further work on education, implementation and identifying clinical research needs for immunonutrition interventions is also vitally needed. SUMMARY This study broadly describes nutritional practices and attitudes of gastrointestinal and oncologic surgeons across the U.S. Surgeons recognize both the importance of proper perioperative surgical nutritional support and the potential value to their practice in terms of outcomes, but this study confirms poor implementation of evidence-based nutrition practices in GI and oncologic surgery programs. This study describes a significant opportunity to capitalize on current favorable surgeon beliefs (and positive published data) regarding the benefit of perioperative nutrition to improve surgical nutrition practice and patient outcomes in the U.S.
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Holmes J, Roberts G, Meran S, Williams JD, Phillips AO. Understanding Electronic AKI Alerts: Characterization by Definitional Rules. Kidney Int Rep 2017; 2:342-349. [PMID: 29142963 PMCID: PMC5678680 DOI: 10.1016/j.ekir.2016.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 11/21/2016] [Accepted: 12/01/2016] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION Automated acute kidney injury (AKI) electronic alerts are based on comparing creatinine with historic results. METHODS We report the significance of AKI defined by 3 "rules" differing in the time period from which the baseline creatinine is obtained, and AKI with creatinine within the normal range. RESULTS A total of 47,090 incident episodes of AKI occurred between November 2013 and April 2016. Rule 1 (>26 μmol/l increase in creatinine within 48 hours) accounted for 9.6%. Rule 2 (≥50% increase in creatinine within previous 7 days) and rule 3 (≥50% creatinine increase from the median value of results within the last 8-365 days) accounted for 27.3% and 63.1%, respectively. Hospital-acquired AKI was predominantly identified by rules 1 and 2 (71.7%), and community-acquired AKI (86.3%) by rule 3. Stages 2 and 3 were detected by rules 2 and 3. Ninety-day mortality was higher in AKI rule 2 (32.4%) than rule 1 (28.3%, P < 0.001) and rule 3 (26.6%, P < 0.001). Nonrecovery of renal function (90 days) was lower for rule 1 (7.9%) than rule 2 (22.4%, P < 0.001) and rule 3 (16.5%, P < 0.001). We found that 19.2% of AKI occurred with creatinine values within normal range, in which mortality was lower than that in AKI detected by a creatinine value outside the reference range (22.6% vs. 29.6%, P < 0.001). DISCUSSION Rule 1 could only be invoked for stage 1 alerts and was associated with acute on chronic kidney disease acquired in hospital. Rule 2 was also associated with hospital-acquired AKI and had the highest mortality and nonrecovery. Rule 3 was the commonest cause of an alert and was associated with community-acquired AKI.
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Moritz J, Turk P, Williams JD, Stone-Roy LM. Perceived Intensity and Discrimination Ability for Lingual Electrotactile Stimulation Depends on Location and Orientation of Electrodes. Front Hum Neurosci 2017; 11:186. [PMID: 28484380 PMCID: PMC5399529 DOI: 10.3389/fnhum.2017.00186] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/29/2017] [Indexed: 11/13/2022] Open
Abstract
Malfunctioning sensory systems can severely impact quality of life and repair is not always possible. One solution, called sensory substitution, is to use another sensory system to bring lost information to the brain. This approach often involves the use of bioengineered devices that electrically stimulate somatosensory fibers. Interestingly, the tongue is an ideal location for electrotactile stimulation due to its dense innervation, moisture, and protected environment. Success with transmitting visual and vestibular information through the tongue indicates promise for future applications. However, sensitivity and discrimination ability varies between individuals and across the tongue surface complicating efforts to produce reliable and consistent sensations. The goals of the present study were to investigate these differences more precisely to better understand the mechanosensory innervation of the tongue so that future electrotactile devices can be designed more effectively. Specifically, we tested whether stimulation of certain regions of the tongue consistently result in better perception, whether the spacing of stimulating electrodes affects perceived intensity, and whether the orientation of electrodes affects perceived intensity and discrimination. To test these hypotheses, we built a custom tongue stimulation device, recruited 25 participants, and collected perceived intensity and discrimination data. We then subjected the data to thorough statistical analyses. Consistent with previous studies, we found that stimulation of the anterior medial tongue region was perceived as more intense than stimulation of lateral and posterior regions. This region also had the best discrimination ability for electrodes. Dividing the stimulated tongue area into 16 distinct regions allowed us to compare perception ability between anterior and posterior regions, medial and lateral regions, and the left and right sides of the tongue. Stimulation of the most anterior and medial tongue resulted in the highest perceived intensity and the best discrimination ability. Most individuals were able to perceive and discriminate electrotactile stimulation better on one side of the tongue, and orientation of stimulating electrodes affected perception. In conclusion, the present studies reveal new information about the somatosensory innervation of the tongue and will assist the design of future electrotactile tongue stimulation devices that will help provide sensory information to people with damaged sensory systems.
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Mullins CR, Farnell CC, Farnell CC, Martinez RA, Liu D, Branam RD, Williams JD. Non-invasive Hall current distribution measurement in a Hall effect thruster. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:013507. [PMID: 28147644 DOI: 10.1063/1.4974098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A means is presented to determine the Hall current density distribution in a closed drift thruster by remotely measuring the magnetic field and solving the inverse problem for the current density. The magnetic field was measured by employing an array of eight tunneling magnetoresistive (TMR) sensors capable of milligauss sensitivity when placed in a high background field. The array was positioned just outside the thruster channel on a 1.5 kW Hall thruster equipped with a center-mounted hollow cathode. In the sensor array location, the static magnetic field is approximately 30 G, which is within the linear operating range of the TMR sensors. Furthermore, the induced field at this distance is approximately tens of milligauss, which is within the sensitivity range of the TMR sensors. Because of the nature of the inverse problem, the induced-field measurements do not provide the Hall current density by a simple inversion; however, a Tikhonov regularization of the induced field does provide the current density distributions. These distributions are shown as a function of time in contour plots. The measured ratios between the average Hall current and the average discharge current ranged from 6.1 to 7.3 over a range of operating conditions from 1.3 kW to 2.2 kW. The temporal inverse solution at 1.5 kW exhibited a breathing mode frequency of 24 kHz, which was in agreement with temporal measurements of the discharge current.
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Holmes J, Rainer T, Geen J, Roberts G, May K, Wilson N, Williams JD, Phillips AO. Acute Kidney Injury in the Era of the AKI E-Alert. Clin J Am Soc Nephrol 2016; 11:2123-2131. [PMID: 27793961 PMCID: PMC5142071 DOI: 10.2215/cjn.05170516] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/08/2016] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND OBJECTIVES Our aim was to use a national electronic AKI alert to define the incidence and outcome of all episodes of community- and hospital-acquired adult AKI. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS A prospective national cohort study was undertaken in a population of 3.06 million. Data were collected between March of 2015 and August of 2015. All patients with adult (≥18 years of age) AKI were identified to define the incidence and outcome of all episodes of community- and hospital-acquired AKI in adults. Mortality and renal outcomes were assessed at 90 days. RESULTS There was a total of 31,601 alerts representing 17,689 incident episodes, giving an incidence of AKI of 577 per 100,000 population. Community-acquired AKI accounted for 49.3% of all incident episodes, and 42% occurred in the context of preexisting CKD (Chronic Kidney Disease Epidemiology Collaboration eGFR); 90-day mortality rate was 25.6%, and 23.7% of episodes progressed to a higher AKI stage than the stage associated with the alert. AKI electronic alert stage and peak AKI stage were associated with mortality, and mortality was significantly higher for hospital-acquired AKI compared with alerts generated in a community setting. Among patients who survived to 90 days after the AKI electronic alert, those who were not hospitalized had a lower rate of renal recovery and a greater likelihood of developing an eGFR<60 ml/min per 1.73 m2 for the first time, which may be indicative of development of de novo CKD. CONCLUSIONS The reported incidence of AKI is far greater than the previously reported incidence in studies reliant on clinical identification of adult AKI or hospital coding data. Although an electronic alert system is Information Technology driven and therefore, lacks intelligence and clinical context, these data can be used to identify deficiencies in care, guide the development of appropriate intervention strategies, and provide a baseline against which the effectiveness of these interventions may be measured.
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Johnson NA, McLeod JM, Holcomb J, Rowe M, Williams JD. Early life history and spatiotemporal changes in distribution of the rediscovered Suwannee moccasinshell Medionidus walkeri (Bivalvia: Unionidae). ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00752] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Abstract
Conservation and intelligence have been found both singly and in combination to be positively related to two measures of reading given 7 mo. after the administration of the conservation measures. However, neither conservation nor intelligence made any significant independent contribution to the prediction of the reading measures when a reading readiness test, administered at the same time as the conservation tasks, was considered in the prediction of reading achievement. When intelligence and reading readiness were separately partialled out of the relationship between conservation and the two measures of reading achievement, the partial correlations dropped to a near-zero value.
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Abstract
In using multiple regression as a data-analysis technique, one problem that might arise is the overuse of a full model with several restricted models, without adjusting the probability level. Such an approach would violate the apparent (or tabled) probability level. This has long been a concern in statistics. The intent of the present paper has been to reconceptualize two of the better known multiple-comparison procedures in a multiple regression approach. The change in the regression approach requires assessing the results of multiple uses of a full model to a correct distribution rather than a straightforward use of the F distribution.
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Movafaghi S, Wang W, Metzger A, Williams DD, Williams JD, Kota AK. Tunable superomniphobic surfaces for sorting droplets by surface tension. LAB ON A CHIP 2016; 16:3204-9. [PMID: 27412084 DOI: 10.1039/c6lc00673f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We utilized tunable superomniphobic surfaces with flower-like TiO2 nanostructures to fabricate a simple device with precisely tailored surface energy domains that, for the first time, can sort droplets by surface tension. We envision that our methodology for droplet sorting will enable inexpensive and energy-efficient analytical devices for personalized point-of-care diagnostic platforms, lab-on-a-chip systems, biochemical assays and biosensors.
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Gaillard WR, Waddell E, Williams JD. Surface Free Energy Determination of APEX Photosensitive Glass. MICROMACHINES 2016; 7:mi7030034. [PMID: 30407407 PMCID: PMC6190264 DOI: 10.3390/mi7030034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 02/06/2016] [Accepted: 02/14/2016] [Indexed: 11/27/2022]
Abstract
Surface free energy (SFE) plays an important role in microfluidic device operation. Photosensitive glasses such as APEX offer numerous advantages over traditional glasses for microfluidics, yet the SFE for APEX has not been previously reported. We calculate SFE with the Owens/Wendt geometric method by using contact angles measured with the Sessile drop technique. While the total SFE for APEX is found to be similar to traditional microstructurable glasses, the polar component is lower, which is likely attributable to composition. The SFE was modified at each stage of device fabrication, but the SFE of the stock and fully processed glass was found to be approximately the same at a value of 51 mJ·m−2. APEX exhibited inconsistent wetting behavior attributable to an inhomogeneous surface chemical composition. Means to produce more consistent wetting of photosensitive glass for microfluidic applications are discussed.
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Basu A, Mills DM, Mitchell D, Ndungo E, Williams JD, Herbert AS, Dye JM, Moir DT, Chandran K, Patterson JL, Rong L, Bowlin TL. Novel Small Molecule Entry Inhibitors of Ebola Virus. J Infect Dis 2015. [PMID: 26206510 DOI: 10.1093/infdis/jiv223] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The current Ebola virus (EBOV) outbreak has highlighted the troubling absence of available antivirals or vaccines to treat infected patients and stop the spread of EBOV. The EBOV glycoprotein (GP) plays critical roles in the early stage of virus infection, including receptor binding and membrane fusion, making it a potential target for the development of anti-EBOV drugs. We report the identification of 2 novel EBOV inhibitors targeting viral entry. METHODS To identify small molecule inhibitors of EBOV entry, we carried out a cell-based high-throughput screening using human immunodeficiency virus-based pseudotyped viruses expressing EBOV-GP. Two compounds were identified, and mechanism-of-action studies were performed using immunoflourescence, AlphaLISA, and enzymatic assays for cathepsin B inhibition. RESULTS We report the identification of 2 novel entry inhibitors. These inhibitors (1) inhibit EBOV infection (50% inhibitory concentration, approximately 0.28 and approximately 10 µmol/L) at a late stage of entry, (2) induce Niemann-Pick C phenotype, and (3) inhibit GP-Niemann-Pick C1 (NPC1) protein interaction. CONCLUSIONS We have identified 2 novel EBOV inhibitors, MBX2254 and MBX2270, that can serve as starting points for the development of an anti-EBOV therapeutic agent. Our findings also highlight the importance of NPC1-GP interaction in EBOV entry and the attractiveness of NPC1 as an antifiloviral therapeutic target.
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Nguyen ST, Kwasny SM, Ding X, Williams JD, Peet NP, Bowlin TL, Opperman TJ. Synthesis and antifungal evaluation of head-to-head and head-to-tail bisamidine compounds. Bioorg Med Chem 2015. [PMID: 26209266 DOI: 10.1016/j.bmc.2015.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Herein, we describe the antifungal evaluation of 43 bisamidine compounds, of which 26 are new, having the scaffold [Am]-[HetAr]-[linker]-[HetAr]-[Am], in which [Am] is a cyclic or acyclic amidine group, [linker] is a benzene, pyridine, pyrimidine, pyrazine ring, or an aliphatic chain of two to four carbon, and [HetAr] is a 5,6-bicyclic heterocycle such as indole, benzimidazole, imidazopyridine, benzofuran, or benzothiophene. In the head-to-head series the two [HetAr] units are oriented such that the 5-membered rings are connected through the linker, and in the head-to-tail series, one of the [HetAr] systems is connected through the 6-membered ring; additionally, in some of the head-to-tail compounds, the [linker] is omitted. Many of these compounds exhibited significant antifungal activity against Candida albicans, Candida krusei, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans (MIC ⩽ 4 μg/ml). The most potent compounds, for example, P10, P19 and P34, are comparable in antifungal activities to amphotericin B (MIC 0.125 μg/ml). They exhibited rapid fungicidal activity (>3 log10 decrease in cfu/ml in 4h) at concentrations equivalent to 4× the MIC in time kill experiments. The bisamidines strongly inhibited DNA, RNA and cell wall biosynthesis in C. albicans in macromolecular synthesis assays. However, the half-maximal inhibitory concentration for DNA synthesis was approximately 30-fold lower than those for RNA and cell wall biosynthesis. Fluorescence microscopy of intact cells of C. albicans treated with a bisamidine exhibited enhanced fluorescence in the presence of DNA, demonstrating that the bisamidine was localized to the nucleus. The results of this study show that bisamidines are potent antifungal agents with rapid fungicidal activity, which is likely to be the result of their DNA-binding activity. Although it was difficult to obtain a broad-spectrum antifungal compound with low cytotoxicity, some of the compounds (e.g., P9, P14 and P43) exhibited favorable CC50 values against HeLa cells and maintained considerable antifungal activity.
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Macdougall IC, Jones JM, Robinson MI, Miles JB, Coles GA, Williams JD. Subcutaneous erythropoietin therapy: comparison of three different sites of injection. CONTRIBUTIONS TO NEPHROLOGY 2015; 88:152-6; discussion 157-8. [PMID: 2040177 DOI: 10.1159/000419525] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Davies M, Stylianou E, Yung S, Thomas GJ, Coles GA, Williams JD. Proteoglycans of CAPD-dialysate fluid and mesothelium. CONTRIBUTIONS TO NEPHROLOGY 2015; 85:134-41. [PMID: 2078932 DOI: 10.1159/000419073] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Williams JD, Beavis JM. Phosphatidylcholine and peritoneal dialysis. CONTRIBUTIONS TO NEPHROLOGY 2015; 85:142-9. [PMID: 2078933 DOI: 10.1159/000419074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Stylianou E, Mackenzie R, Davies M, Coles GA, Williams JD. The interaction of organism, phagocyte and mesothelial cell. CONTRIBUTIONS TO NEPHROLOGY 2015; 85:30-8. [PMID: 2078937 DOI: 10.1159/000419060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Macdougall IC, Roberts DE, Neubert P, Dharmasena AD, Coles GA, Williams JD. Pharmacokinetics of intravenous, intraperitoneal, and subcutaneous recombinant erythropoietin in patients on CAPD. A rationale for treatment. CONTRIBUTIONS TO NEPHROLOGY 2015; 76:112-20; discussion 120-1. [PMID: 2684515 DOI: 10.1159/000417887] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Macdougall IC, Cavill I, Davies ME, Hutton RD, Coles GA, Williams JD. Subcutaneous recombinant erythropoietin in the treatment of renal anaemia in CAPD patients. CONTRIBUTIONS TO NEPHROLOGY 2015; 76:219-26. [PMID: 2582780 DOI: 10.1159/000417898] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Komazin-Meredith G, Cardinale SC, Comeau K, Magalhaes KJ, Hartline CB, Williams JD, Opperman TJ, Prichard MN, Bowlin TL. TAOK3 phosphorylates the methylenecyclopropane nucleoside MBX 2168 to its monophosphate. Antiviral Res 2015; 119:23-7. [PMID: 25857706 DOI: 10.1016/j.antiviral.2015.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/30/2015] [Accepted: 04/01/2015] [Indexed: 12/14/2022]
Abstract
Monohydroxymethyl methylenecyclopropane nucleosides (MCPNs) with ether or thioether substituents at the 6-position show promise as broad-spectrum herpes virus inhibitors. Their proposed mechanism of action involves sequential phosphorylation to a triphosphate, which can then inhibit viral DNA polymerase. The inhibition of herpes simplex virus (HSV) by these compounds is not dependent on the viral thymidine kinase (TK), which is known to phosphorylate acyclovir (ACV), a standard treatment for HSV infections. Previous studies on the mechanism of action of these compounds against human cytomegalovirus (HCMV) implicated a host kinase in addition to HCMV UL97 kinase in performing the initial phosphorylation. After first eliminating other candidate HSV-1 encoded kinases (UL13 and US3) as well as potential host nucleoside kinases, using activity-based fractionation, we have now identified the host serine-threonine protein kinase TAOK3 as the kinase responsible for transforming the representative monohydroxymethyl MCPN analog MBX 2168 to its monophosphate.
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Nguyen ST, Kwasny SM, Ding X, Cardinale SC, McCarthy CT, Kim HS, Nikaido H, Peet NP, Williams JD, Bowlin TL, Opperman TJ. Structure-activity relationships of a novel pyranopyridine series of Gram-negative bacterial efflux pump inhibitors. Bioorg Med Chem 2015; 23:2024-34. [PMID: 25818767 DOI: 10.1016/j.bmc.2015.03.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 02/25/2015] [Accepted: 03/05/2015] [Indexed: 12/24/2022]
Abstract
Recently we described a novel pyranopyridine inhibitor (MBX2319) of RND-type efflux pumps of the Enterobacteriaceae. MBX2319 (3,3-dimethyl-5-cyano-8-morpholino-6-(phenethylthio)-3,4-dihydro-1H-pyrano[3,4-c]pyridine) is structurally distinct from other known Gram-negative efflux pump inhibitors (EPIs), such as 1-(1-naphthylmethyl)-piperazine (NMP), phenylalanylarginine-β-naphthylamide (PAβN), D13-9001, and the pyridopyrimidine derivatives. Here, we report the synthesis and biological evaluation of 60 new analogs of MBX2319 that were designed to probe the structure activity relationships (SARs) of the pyranopyridine scaffold. The results of these studies produced a molecular activity map of the scaffold, which identifies regions that are critical to efflux inhibitory activities and those that can be modified to improve potency, metabolic stability and solubility. Several compounds, such as 22d-f, 22i and 22k, are significantly more effective than MBX2319 at potentiating the antibacterial activity of levofloxacin and piperacillin against Escherichia coli.
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Williams JD, Torhan MC, Neelagiri VR, Brown C, Bowlin NO, Di M, McCarthy CT, Aiello D, Peet NP, Bowlin TL, Moir DT. Synthesis and structure-activity relationships of novel phenoxyacetamide inhibitors of the Pseudomonas aeruginosa type III secretion system (T3SS). Bioorg Med Chem 2015; 23:1027-43. [PMID: 25638499 PMCID: PMC4339527 DOI: 10.1016/j.bmc.2015.01.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 12/29/2014] [Accepted: 01/06/2015] [Indexed: 01/01/2023]
Abstract
The increasing prevalence of drug-resistant bacterial infections is driving the discovery and development not only of new antibiotics, but also of inhibitors of virulence factors that are crucial for in vivo pathogenicity. One such virulence factor is the type III secretion system (T3SS), which plays a critical role in the establishment and dissemination of Pseudomonas aeruginosa infections. We have recently described the discovery and characterization of a series of inhibitors of P. aeruginosa T3SS based on a phenoxyacetamide scaffold. To better characterize the factors involved in potent T3SS inhibition, we have conducted a systematic exploration of this structure, revealing several highly responsive structure-activity relationships indicative of interaction with a specific target. Most of the structural features contributing to potency were additive, and combination of those features produced optimized inhibitors with IC50 values <1μM.
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