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1.
Travel Med Infect Dis ; 52: 102540, 2023.
Article in English | MEDLINE | ID: mdl-36587754

ABSTRACT

With the emergence of SARS-CoV-2 and now monkeypox, the UK Defence Medical Services have been required to provide rapid advice in the management of patients with airborne high consequence infectious diseases (A-HCID). The Defence Public Health Network (DPHN) cadre, consisting of closely aligned uniformed and civilian public health specialists have worked at pace to provide evidence-based recommendations on the clinical management, public health response and policy for monkeypox, with military medicine and pathology clinicians (primarily infectious disease physicians and medical microbiologists). Military environments can be complicated and nuanced requiring specialist input and advice to non-specialists as well as unit commanders both in the UK and overseas. DPHN and military infection clinicians have close links with the UK National Health Service (NHS) and the UK Health Security Agency (UKHSA), allowing for a dynamic two-way relationship that encompasses patient management, public health response, research and development of both UK military and national guidelines. This is further demonstrated with the Royal Air Force (RAF) Air Transport Isolator (ATI) capability, provided by Defence to support the UK Government and UKHSA. Military infectious disease clinicians are also embedded within NHS A-HCID units. In this manuscript we provide examples of the close interdisciplinary working of the DPHN and Defence clinicians in managing military monkeypox patients, co-ordinating the public health response, advising the Command and developing monkeypox policy for Defence through cross-government partnership. We also highlight the co-operation between civilian and military medical authorities in managing the current outbreak.


Subject(s)
COVID-19 , Communicable Diseases , Military Medicine , Military Personnel , Mpox (monkeypox) , Humans , Mpox (monkeypox)/epidemiology , State Medicine , COVID-19/epidemiology , SARS-CoV-2 , Disease Outbreaks , United Kingdom/epidemiology , Communicable Diseases/epidemiology
2.
J Mech Behav Biomed Mater ; 123: 104767, 2021 11.
Article in English | MEDLINE | ID: mdl-34455140

ABSTRACT

Particulate reinforcement of polymeric matrices is a powerful technique for tailoring the mechanical and degradation properties of bioresorbable implant materials. Dispersion of inorganic particles is critical to achieving optimal properties, however established techniques such as twin-screw extrusion or solvent casting can have significant drawbacks including excessive thermal degradation or particle agglomeration. We present a facile method for production of polymer-inorganic composites that reduces the time at elevated temperature and the time available for particle agglomeration. Glass slurry was added to a dissolved PLLA solution, and ethanol was added to precipitate polymer onto the glass particles. Characterisation of parts formed by subsequent micro-injection moulding of composite precipitate revealed a significant reduction in agglomeration, with d0.9 reduced from 170 to 43 µm. This drastically improved the ductility (ɛB) from 7% to 120%, without loss of strength or stiffness. The method is versatile and applicable to a wide range of polymer and filler materials.


Subject(s)
Polyesters , Polymers , Glass , Tensile Strength
3.
Lasers Med Sci ; 35(6): 1263-1270, 2020 Aug.
Article in English | MEDLINE | ID: mdl-31729610

ABSTRACT

Laser micromachining with ultrashort pulses has shown great promise for clean, safe surgical treatment of bone tissue. However, comparisons of performance and development of "best practice" have been hampered by the difficulty of comparing results across a wide variety of experimental approaches and under surgically irrelevant conditions (e.g., dried, dead bone). Using a femtosecond (fs) pulsed laser system (τ = 140 fs, repetition rate = 1 kHz, λ = 800 nm), a comprehensive study of femtosecond laser microsurgery using the standard metrics of laser micromachining (ablation threshold, incubation effects, ablation rates, effect of focal point depth within the material and heat affected zone (HAZ)) was conducted on live, freshly harvested bovine and ovine cortical bone. Three important points of optimism for future implementation in the surgical theatre were identified: (1) the removal of material is relatively insensitive to the focal point depth within the material, removing the need for extreme depth precision for excellent performance; (2) femtosecond laser ablation of fresh bone demonstrates very little incubation effect, such that multiple passes of the laser over the same region of bone removes the same amount of material; and (3) the complete absence of collateral damage, heat- or shock-induced, on both the macro- and microscopic scales can be achieved readily, within a broad parameter range. Taken together, these results indicate a handheld or robotic deployed fiber laser platform for femtosecond laser microsurgery is a very viable prospect.


Subject(s)
Lasers , Orthopedic Procedures , Animals , Cattle , Cortical Bone/ultrastructure , Female , Male , Sheep , Time Factors , Tomography, Optical Coherence
4.
Opt Express ; 26(26): 34558-34568, 2018 Dec 24.
Article in English | MEDLINE | ID: mdl-30650878

ABSTRACT

Femtosecond laser micromachining holds significant promise for advanced manufacturing, however uptake has been limited by the low processing speed. Altering the beam shape from its typical Gaussian profile has been attempted to improve efficiency, however virtually all reliable methods for quantifying the efficiency assume a Gaussian beam shape. Here, we describe an approach for quantifying the ablation threshold fluence - the key parameter for comparing efficiency - suitable for weakly focused non-Gaussian beams. We successfully demonstrate this method for Bessel and vortex beams, finding that the ablation threshold depends not just on the material, but the beam shape as well.

5.
Anal Bioanal Chem ; 408(16): 4403-11, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27086022

ABSTRACT

Nanostructured gold substrates provide chemically stable, signal-enhancing substrates for the sensitive detection of a variety of compounds through surface-enhanced Raman spectroscopy (SERS). Recent developments in advanced fabrication methods have enabled the manufacture of SERS substrates with repeatable surface nanostructures that provide reproducible quantitative analysis, historically a weakness of the SERS technique. Here, we describe the novel use of gold-sputtered Blu-ray disc surfaces as SERS substrates. The unique surface features and composition of the Blu-ray disc recording surface lead to the formation of gold nano-islands and nanogaps following simple gold sputtering, without any background peaks from the substrate. The SERS performance of this substrate is strong and reproducible with an enhancement factor (EF) of 10(3) for melamine. A limit of detection (LOD) for this compound of 70 ppb and average reproducibility of ±12 % were achieved. Gold-sputtered Blu-ray discs thus offer an excellent alternative to more exotic gold SERS substrates prepared by advanced, time-consuming and expensive methods. Graphical abstract AFM 3D images of 1-µm(2) sections of uncoated and gold-sputtered recordable Blu-ray disc (BD-R) surfaces and the SERS signal obtained on the gold-sputtered surface for a 1000 ppm aqueous solution of melamine.

6.
J Biomed Mater Res A ; 103(1): 311-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24659540

ABSTRACT

Magnesium and its alloys are intriguing as possible biodegradable biomaterials due to their unique combination of biodegradability and high specific mechanical properties. However, uncontrolled biodegradation of magnesium during implantation remains a major challenge in spite of the use of alloying and protective coatings. In this study, a hybrid composite structure of magnesium metal and a biopolymer was fabricated as an alternative approach to control the corrosion rate of magnesium. A multistep process that combines metal foam production and injection molding was developed to create a hybrid composite structure that is topologically ordered in all three dimensions. Preliminary investigations of the mechanical properties and corrosion behavior exhibited by the hybrid Mg-polymer composite structures suggest a new potential approach to the development of Mg-based biomedical devices.


Subject(s)
Biopolymers/chemistry , Magnesium/chemistry , Corrosion , Materials Testing , Microscopy, Electron, Scanning
8.
Oncogene ; 19(7): 889-98, 2000 Feb 17.
Article in English | MEDLINE | ID: mdl-10702797

ABSTRACT

Mammary tumorigenesis was analysed in transgenic mice which overexpress des(1-3)hIGF-I (WAP-DES) and/or a mutant form of p53 (p53172R-H). Nonlactating, multiparous WAP-DES mice exhibited hyperplastic lesions termed mammary interepithelial neoplasia (MIN) which constitutively expressed WAP-DES. By 23 months of age, 53% of the WAP-DES mice developed mammary adenocarcinomas. A 75% reduction in both apoptosis and proliferation was observed in the normal mammary glands of WAP-DES mice. Mammary tumor incidence in WAP-DES/p53 bitransgenic mice was similar to that of WAP-DES and 2 - 3-fold greater than that of nontransgenic and p53172R-H females. Tumor latency, however, was reduced by 8 months in bitransgenic mice as compared to mice of the other three genotypes. Aneuploidy was frequently observed in tumors from bitransgenic and p53172R-H mice, but not from mice expressing only the WAP-DES transgene. Expression of IGFBP3 was elevated in tumors from WAP-DES, but not bitransgenic mice, indicating an alteration in the p53/IGF-I axis. These studies indicate that overexpression of des(1-3)hIGF-I increases the frequency of MIN and stochastic mammary tumors and that the appearance of tumors displaying genomic instability is accelerated by mutant p53172R-H. Oncogene (2000) 19, 889 - 898.


Subject(s)
Insulin-Like Growth Factor I/metabolism , Mammary Neoplasms, Experimental/etiology , Mammary Neoplasms, Experimental/genetics , Mutation/genetics , Peptide Fragments/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Animals , Apoptosis/genetics , DNA Replication/genetics , Drug Synergism , Female , Male , Mammary Neoplasms, Experimental/metabolism , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Inbred ICR , Mice, Transgenic
9.
Blood Coagul Fibrinolysis ; 4(3): 397-403, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8329564

ABSTRACT

The interaction of the platelet surface with agonist or adhesive molecules can modify the platelet surface charge and thus its electrophoretic mobility. Electrophoretic quasi elastic light scattering (ELS) is a technique that permits the rapid and accurate determination of electrophoretic mobility of platelets. ELS was used to study changes in the platelet electrophoretic mobility induced by platelet activation and by fibrinogen binding. The platelet electrophoretic mobility decreases from -2 (mu-cm)/(V-s) to -0.5 (mu-cm)/(V-s) when the platelet is activated with either 1 microM ADP, 10 microM epinephrine or 0.5 NIH U/ml alpha-thrombin. Aspirin inhibits the ADP induced platelet activation and surface charge reduction. Thrombin overcomes the aspirin inhibition indication that the platelet surface charge reduction is associated with platelet activation. The magnitude of the decrease in the platelet electrophoretic mobility varies with the platelet donor and the extent of platelet activation. Platelet activation enhances the fibrinogen induced surface charge reduction, which is consistent with fibrinogen binding. Thus, ELS is shown to be a sensitive means to directly assess platelet activation and ligand binding.


Subject(s)
Blood Platelets/metabolism , Electrophoresis/methods , Fibrinogen/metabolism , Nephelometry and Turbidimetry , Platelet Activation , Platelet Membrane Glycoproteins/metabolism , Aspirin/pharmacology , Epinephrine/pharmacology , Humans , Platelet Activation/drug effects , Protein Binding/drug effects , Thrombin/pharmacology
11.
Circ Res ; 68(3): 881-7, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1742873

ABSTRACT

The effect of the radiographic contrast agents, iopamidol and diatrizoate, on fibrin assembly and structure as well as platelet surface charge was studied. Increasing the iopamidol concentration from 0 to 4.5 mM prolongs the fibrin gelation time from 20 to 105 seconds (an anticoagulant effect) and reduces the fibrin fiber mass/length ratio from 3.2 x 10(12) to 0.5 x 10(12) Da/cm (i.e., produces very thin fibrin fibers). Ultraviolet difference spectroscopy of fibrinogen showed both a 15-nm shift in the ultraviolet difference maximum for iopamidol (suggesting binding) and a perturbation of the aromatic amino acid side chain region for fibrinogen (suggesting a conformational change in fibrinogen) as the concentration of iopamidol was increased from 0 to 9 mg/ml. Binding of iopamidol to fibrinogen was also shown by affinity chromatography using a Sepharose-fibrinogen column. Electrophoretic quasi elastic light scattering was used to show platelet interaction with iopamidol as reflected in a reduction in the platelet electrophoretic mobility from 2.0 to 0.5 (microns-cm)/(V-sec) as the concentration of iopamidol was increased from 0 to 4.5 mM. In addition, the ionic radiopaque contrast agent, Renografin, was also studied and found to inhibit fibrin monomer assembly. Although iopamidol is not shown to be thrombogenic, iopamidol does appear to reduce platelet surface charge, bind fibrinogen, and modify fibrin clot structure.


Subject(s)
Blood Platelets/drug effects , Contrast Media/pharmacology , Diatrizoate/pharmacology , Fibrin/metabolism , Iopamidol/pharmacology , Electrophoresis , Fibrin/chemistry , Humans , Light , Scattering, Radiation
12.
Percept Mot Skills ; 44(2): 540-2, 1977 Apr.
Article in English | MEDLINE | ID: mdl-141034

ABSTRACT

In a study designed to determine whether future teachers have negative sttitudes toward groups of exceptional children based upon the labels attached to these children, 13 special education majors and 32 students majoring in other fields of education were administered the Personal Attribute Inventory at the beginning and conclusion of an introductory course in special education. Results for labels, physically handicapped, educable mentally handicapped, and learning disabled, indicated that the latter two were evaluated significantly less positively than the first on both pre- and post-course testings. There were no significant differences between the respondents' pre- and post-course ratings of the three labels. Interestingly, special education majors were significanlty more positive in their pre- and post-course evaluations than non-special education majors. These findings certainly are not supportive of "mainstreaming" children who have been categorized as either learning disabled or educable mentally handicapped.


Subject(s)
Attitude , Disabled Persons , Teaching , Education of Intellectually Disabled , Education, Special , Female , Humans , Intellectual Disability , Learning Disabilities , Male , Sex Factors
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