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1.
Ir J Med Sci ; 193(4): 1891-1900, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38565823

ABSTRACT

BACKGROUND: Escherichia coli is the predominant urinary pathogen in children. Irish and international studies have demonstrated increasing antimicrobial resistance (AMR) to antibiotics such as co-amoxiclav. AIMS: We aimed to (1) examine the AMR patterns of paediatric urinary E. coli isolates, from both hospital and community sources, over a 10-year period; (2) assess the effectiveness of Children's Health Ireland (CHI) antimicrobial guidance given local susceptibility data; and (3) review the clinical management of an admitted patient sub-set over a 6-year period. METHODS: Pure growth of urinary E. coli from patients aged ≤ 14 from 2012 to 2021 were analysed for AMR. Differences in susceptibility rates were assessed. A retrospective chart review conducted on inpatients aged ≥ 2 months to ≤ 14 years, 2016-2021. RESULTS: E. coli accounted for 70.8% of likely significant positive pure growth cultures (9314 isolates). Susceptibility to co-amoxiclav significantly increased over time, from 66.7% to 80.4% (2016-2021, p < 0.001). Nitrofurantoin and cefalexin had significantly higher susceptibility rates than trimethoprim (< 70% annually). 85.1% of isolates were susceptible to the combination of co-amoxiclav and gentamicin, recommended for those > 2months and systemically unwell. The additional gain in empiric susceptibility provided by gentamicin above that provided by co-amoxiclav alone has fallen from 16.4% to 6.7% (2016-2021). The 222 clinical cases reviewed showed improved antimicrobial guideline compliance over time. CONCLUSIONS: This study provides important regional AMR data. Co-amoxiclav susceptibility increased significantly over time, contrasting with previous studies. This was temporally associated with stewardship measures reducing co-amoxiclav prescribing. Decreasing utility of gentamicin supports recent CHI guideline updates reducing gentamicin use.


Subject(s)
Anti-Bacterial Agents , Escherichia coli Infections , Escherichia coli , Urinary Tract Infections , Humans , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology , Retrospective Studies , Escherichia coli Infections/drug therapy , Child , Infant , Anti-Bacterial Agents/therapeutic use , Escherichia coli/drug effects , Escherichia coli/isolation & purification , Child, Preschool , Female , Male , Adolescent , Microbial Sensitivity Tests , Amoxicillin-Potassium Clavulanate Combination/therapeutic use , Drug Resistance, Bacterial , Ireland/epidemiology , Nitrofurantoin/therapeutic use , Trimethoprim/therapeutic use
2.
Soft Robot ; 5(6): 726-736, 2018 12.
Article in English | MEDLINE | ID: mdl-30148682

ABSTRACT

This article presents a direct additive manufacturing method for composite material soft pneumatic actuators that are capable of performing a range of programmable motions. Commonly, molding is the method used to manufacture soft fluidic actuators. This is material, labor, and time intensive and lacks the design freedom to produce custom actuators efficiently. This article proposes an alternative semiautomated method of designing and manufacturing composite soft actuators. An affordable, open-source, desktop three-dimensional (3D) printer was modified into a four-axis, combined, fused deposition modeling, and paste extrusion printer. A Grasshopper 3D algorithm was devised to implement custom actuator designs according to user inputs, resulting in a G-code print file. Bending, contracting, and twisting motion actuators were parametrically designed and subsequently additively manufactured from silicone and thermoplastic elastomer (TPE) materials. Experimental testing was completed on these actuators along with their constitutive materials. Finite element models were created to simulate the actuator's kinematic performance. Having a platform method to digitally configure and directly additively manufacture custom-motion, composite soft actuators has the potential to accelerate the development of more intricate designs and lead to potential impacts in a range of areas, including in-clinic personalization of soft assistive devices and patient-specific biomedical devices.

3.
Anat Sci Educ ; 9(6): 555-564, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27096280

ABSTRACT

E-Learning is becoming an integral part of undergraduate medicine, with many curricula incorporating a number of online activities and resources, in addition to more traditional teaching methods. This study examines physical attendance, online activity, and examination outcomes in a first-year undergraduate medical program. All 358 students who completed the Alimentary System module within the first semester of the program were included, 30 of whom were repeating the year, and thus the module. This systems-based, multidisciplinary module incorporated didactic lectures, cadaveric small group tutorials and additional e-Learning resources such as online histology tutorials. Significant differences were demonstrated in physical attendance and utilization of online resources between repeating students and those participating in the module for the first time. Subsequent analyses confirmed that physical attendance, access of online lecture resources, and utilization of online histology tutorials were all significantly correlated. In addition, both physical attendance and utilization of online resources significantly correlated with summative examination performance. While nonattendance may be due to a variety of factors, our data confirm that significant differences exist in both physical attendance and online activity between new entrants and repeating students, such that all students repeating a module or academic year should be routinely interviewed and offered appropriate supports to ensure that they continue to engage with the program. While the development of complex algorithmic models may be resource intensive, using readily available indices from virtual learning environments is a straightforward, albeit less powerful, means to identify struggling students prior to summative examinations. Anat Sci Educ 9: 555-564. © 2016 American Association of Anatomists.


Subject(s)
Anatomy/education , Computer-Assisted Instruction/statistics & numerical data , Digestive System Physiological Phenomena , Digestive System/anatomy & histology , Education, Medical, Undergraduate/methods , Internet/statistics & numerical data , Learning , Physiology/education , Students, Medical/psychology , Curriculum , Educational Measurement , Educational Status , Humans , Time Factors , Workload
4.
J Fluoresc ; 15(3): 287-99, 2005 May.
Article in English | MEDLINE | ID: mdl-15986154

ABSTRACT

This mini review highlights the synthesis and photophysical evaluation of anion sensors, for nonaqueous solutions, that have been developed in our laboratories over the last few years. We have focused our research mainly on developing fluorescent photoinduced electron transfer (PET) sensors based on the fluorophore-spacer-anion receptor principle using several anthracene (emitting in the blue) and 1,8-naphthalimide (emitting in the green) fluorophores, with the aim of targeting biologically and industrially relevant anions such as acetates, phosphate and amino acids, as well as halides such as fluoride. The receptors and the fluorophore are separated by a short methyl or ethyl spacer, where the charge neutral anion receptors are either aliphatic or aromatic urea (or thiourea) moieties. For these, the anion recognition is through hydrogen bonding, yielding anion:receptor complexes. Such bonding gives rise to enhanced reduction potential in the receptor moieties which causes enhancement in the rate of PET quenching of the fluorophore excited state from the anion:receptor moiety. This design can be further elaborated on by incorporating either two fluorophores, or urea/thiourea receptors into the sensor structures, using anthracene as a fluorophore. For the latter design, the sensors were designed to achieve sensing of bis-anions, such as di-carboxylates or pyrophosphate, where the anion bridged the anthracene moiety. In the case of the naphthalimide based mono-receptor based PET sensors, it was discovered that in DMSO the sensors were also susceptible to deprotonation by anions such as F(-) at high concentrations. This led to substantial changes in the absorption spectra of these sensors, where the solution changed colour from yellow/green to deep blue, which was clearly visible to the naked eye. Hence, some of the examples presented can act as dual fluorescent-colorimetric sensors for anions. Further investigations into this phenomenon led to the development of simple colorimetric sensors for fluorides, which upon exposure to air, were shown to fix carbon dioxide as bicarbonate.

5.
Org Biomol Chem ; 3(1): 48-56, 2005 Jan 07.
Article in English | MEDLINE | ID: mdl-15602598

ABSTRACT

The synthesis of the fluorescent photoinduced electron transfer (PET) chemosensors 1-3 for bis-anions such as bis-carboxylates and pyrophosphate in organic solvents is described herein. These sensors are based on the receptor-spacer-fluorophore-spacer-receptor motif where the receptors are charge neutral aromatic thiourea or urea receptors and the fluorophore is anthracene. The anion recognition was evaluated using 1H NMR as well as absorption and fluorescence spectroscopy in DMSO. For simple anions such as acetate or fluoride, the recognition was shown to be through hydrogen bonding of the corresponding anion to the receptors. This gave rise to only minor changes in the absorption spectra, but significant changes in the fluorescence emission spectra, which was substantially (70-95%) quenched. Analysis of these recognition events implied a 1 : 2 (sensor : anion) binding and ideal PET behaviour for ions such as AcO- and H2PO4-. For F-, the luminescent quenching indicated a 1 : 1 binding, but we deduced that this was due more to complete quenching of the excited state after the addition of one equivalent of the anion. For all of the anions, the quenching contributed to enhanced efficiency of PET from the receptors to the excited state of the fluorophore. In the case of the bis-anions (ambient), such as di-carboxylates, similar fluorescence quenching was observed. However, here either a 1 : 1 or a 1 : 2 binding was observed depending on the length of the spacer separating the two carboxylate moieties and the nature of the receptor. Whereas both pyrophosphate and malonate gave rise to a 1 : 1 binding, glutarate gave rise to approximately 1 : 2 binding for the thiourea sensors 1 and 2. However, for the urea based sensor 3, the binding was found to be 1 : 1 for all the bis-anions. For such a 1 : 1 binding we propose that the anion most likely bridges the fluorophore moiety. This was also evident from the 1H NMR (DMSO-d6) spectrum where the anthracene resonances were significantly affected. By simply modifying the electronic structure of the receptor, the sensitivity of the recognition process could also be modified; e.g. compound 1, bearing the trifluoromethyl substituent, showed stronger binding to the bis-anions than 2, which possessed a simple phenyl moiety.


Subject(s)
Dicarboxylic Acids/chemistry , Diphosphates/chemistry , Fluorescent Dyes/chemistry , Thiourea/chemistry , Urea/chemistry , Chemical Phenomena , Chemistry, Physical , Electron Transport , Hydrogen Bonding , Ion-Selective Electrodes , Magnetic Resonance Spectroscopy/methods , Molecular Structure , Photochemistry , Solvents/chemistry
6.
Org Biomol Chem ; 2(13): 1856-63, 2004 Jul 07.
Article in English | MEDLINE | ID: mdl-15227537

ABSTRACT

The synthesis of four fluorescent photoinduced electron transfer (PET) chemosensors 1-4 for anions is described. These are all based on a simple design employing charge neutral aliphatic or aromatic thiourea anion receptors connected to an anthracene fluorophore via a methylene spacer. Here the anion recognition occurred through 1 : 1 hydrogen bonding between the thiourea protons and the anion, as demonstrated by observing the changes in the (1)H NMR in DMSO-d(6) where the two thiourea protons were shifted downfield upon addition of anions. Whereas 1-3 were designed for the detection of anions such as fluoride, acetate or phosphate, 4 was made for the recognition of N-protected amino acids. All the sensors showed 'ideal' behaviour where only the fluorescence emission was quenched upon anion recognition, due to enhanced efficiency of electron transfer quenching from the receptor to the excited state of the fluorophore. By simply varying the nature of the thiourea substituent it was possible to modulate, or tune, the acidity of the thiourea receptor moiety, altering the sensitivity of the anion recognition. For, the anion selectivity and the degree of the fluorescence quenching were in the order of F(-) > AcO(-) > H(2)PO(4)(-), with Cl(-) or Br(-) not being detected.


Subject(s)
Electron Transport , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Photochemistry , Thiourea/chemistry , Amines/chemistry , Amino Acids/chemistry , Anions/chemical synthesis , Anions/chemistry , Dimethyl Sulfoxide , Hydrogen Bonding , Molecular Structure , Spectrum Analysis , Static Electricity , Stereoisomerism , Temperature , Titrimetry
7.
Org Lett ; 4(15): 2449-52, 2002 Jul 25.
Article in English | MEDLINE | ID: mdl-12123348

ABSTRACT

[reaction: see text] The fluorescent photoinduced electron transfer (PET) chemosensors 2 and 3 were designed for the recognition of anions possessing two binding sides such as dicarboxylates and pyrophosphate; the anion recognition in DMSO takes place through the two charge neutral thiourea receptor sites with concomitant PET quenching of the anthracene moiety. The anion binding of acetate, phosphate, and pyrophosphate to 2 and 3 was also evaluated by using 1H NMR in DMSO-d6.


Subject(s)
Biosensing Techniques/methods , Dicarboxylic Acids/analysis , Diphosphates/analysis , Anions/analysis , Binding Sites , Electrons , Fluorescence , Magnetic Resonance Spectroscopy , Titrimetry
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