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1.
Clin Exp Dermatol ; 47(5): 903-909, 2022 May.
Article in English | MEDLINE | ID: mdl-34826169

ABSTRACT

BACKGROUND: The lack of validated and responsive outcome measures in the management of frontal fibrosing alopecia (FFA) significantly limits assessment of disease progression and treatment response over time. AIM: To understand how FFA extent and progression is currently assessed in UK specialist centres, to validate components of the International FFA Cooperative Group (IFFACG) statement on FFA assessment, and to identify pragmatic advice to improve FFA management in clinic. METHODS: Consultant dermatologists with a specialist interest in hair loss (n = 17) were invited to take part. Preferred FFA assessment methods were explored using questionnaires and clinical scenarios. Participants were asked to identify and mark the current hairline in 10 frontal and 10 temporal hairline images (Questionnaire 1), with assessment repeated 3 months later to assess intraindividual variability (Questionnaire 2) and 12 months later to test whether interindividual accuracy could be improved with simple instruction (Questionnaire 3). RESULTS: All 17 clinicians (100%) completed the questionnaire at each time interval. We identified a wide variation in assessment techniques used by our experts. Measurements were perceived as the most accurate method of assessing frontal recession whereas photography was preferred for temporal recession. Inter-rater reliability between clinicians measuring the frontal hairline scenarios indicated a moderate strength of agreement [intraclass coefficient (ICC) = 0.61; 95% CI 0.40-0.85], yet intrarater reliability was found to be poor with wide limits of agreement (-8.71 mm to 9.92 mm) on follow-up. Importantly, when clear guidance was provided on how the hairline should be identified (Questionnaire 3), inter-rater reliability improved significantly, with ICC = 0.70, suggesting moderate agreement (95% CI 0.51-0.89; P < 0.001). A similar pattern was seen with temporal hairline measurements, which again improved in accuracy with instruction. CONCLUSION: We found that accuracy of measurements in FFA can be improved with simple instruction and we have validated components of the IFFACG measurement recommendations.


Subject(s)
Alopecia , Lichen Planus , Alopecia/diagnosis , Alopecia/drug therapy , Humans , Reproducibility of Results , Surveys and Questionnaires
2.
Angew Chem Int Ed Engl ; 55(6): 2132-6, 2016 Feb 05.
Article in English | MEDLINE | ID: mdl-26762559

ABSTRACT

Small changes in the structure of a foldamer may lead to gross changes in conformational preference. We show that the simple insertion or deletion of a single hydrogen bond by changes in pH or by photochemical deprotection is sufficient to refold a helical oligomer, interconverting M and P screw-sense preference. As a consequence of the switch, information may be transmitted to a remote catalytic site, selectively directing the formation of either of two enantiomeric products by a reaction involving 1,22-remote intermolecular asymmetric induction.

4.
Spinal Cord ; 52(9): 652-7, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24891012

ABSTRACT

OBJECTIVE: To develop an International Spinal Cord Injury (SCI) Upper Extremity Basic Data Set as part of the International SCI Data Sets, which facilitates consistent collection and reporting of basic upper extremity findings in the SCI population. SETTING: International. METHODS: A first draft of a SCI Upper Extremity Data Set was developed by an international working group. This was reviewed by many different organisations, societies and individuals over several months. A final version was created. VARIABLES: The final version of the International SCI Upper Extremity Data Set contains variables related to basic hand-upper extremity function, use of assistive devices, SCI-related complications to upper extremity function and upper extremity/hand reconstructive surgery. Instructions for data collection and the data collection form are freely available on the ISCoS website (www.iscos.org.uk). CONCLUSION: The International SCI Upper Extremity Basic Data Set will facilitate consistent collection and reporting of basic upper extremity findings in the SCI population.


Subject(s)
Databases, Factual , International Cooperation , Spinal Cord Injuries/complications , Spinal Cord Injuries/physiopathology , Upper Extremity/physiopathology , Data Collection , Humans
5.
Public Health ; 127(1): 39-45, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23219265

ABSTRACT

OBJECTIVES: To assess what makes a good piece of medical reporting in newspapers, to quantify what is being reported on in the major British newspapers, to identify the sources of the news threads, and to assess how these are reported. STUDY DESIGN: Development and validation of a tool to assess the quality of reporting of health-related articles, and assessment of the quality of these articles in British newspapers. METHODS: Eight national daily newspapers from the UK were reviewed for 20 days over a 2-month period. All articles reporting newly emerging research pertaining to health in humans were included and reviewed independently by two raters. A descriptive analysis was performed. Subsequently, a quality assessment tool for use by a non-expert was developed and validated to objectively assess the quality of a newspaper article on a health-related topic. RESULTS: The quality assessment tool was found to have good internal consistency and inter-rater reliability. The Daily Mail published almost twice as many articles as its nearest rival, The Daily Express, and over eight times as many articles as The Guardian. Articles in The Times were, on average, more than twice as long as those in The Sun and The Daily Telegraph. The highest quality articles were in The Times and The Independent, with the lowest quality articles in The Sun. The quality scores of anonymous articles were significantly lower than those attributed to named journalists. CONCLUSIONS: There are significant differences in the quality of reporting within and between major daily UK newspapers, with anonymous articles being the poorest quality, and widespread reliance on press releases from the major UK scientific journals.


Subject(s)
Journalism, Medical/standards , Newspapers as Topic/standards , Cross-Sectional Studies , Humans , Newspapers as Topic/statistics & numerical data , Reproducibility of Results , United Kingdom
6.
Chem Sci ; 13(8): 2258-2269, 2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35310487

ABSTRACT

Molecules that change shape in response to environmental conditions are central to biological molecular communication devices and their synthetic chemical analogues. Here we report a molecular system in which a series of chiral anionic ligands of differing basicity are selectively protonated according to the pH of the medium. A cationic circular dichroism (CD) reporter complex responds to anion binding by selecting one of two alternative enantiomeric conformations. Exploiting the principle that less basic anions have, in general, weaker electrostatic interactions than more basic anions, a set of three chiral acids with large (>5 unit) pK a differences and differing configurations were sequentially deprotonated in acetonitrile by addition of base, allowing the most basic anion in the mixture at any time to bind to the reporter complex. A characteristic CD output resulted, which changed in sign as the next-most basic anion was revealed by the next deprotonation in the series. Four cycles of switching between three ligand-bound states were achieved with minimal changes in signal magnitude, by alternating addition of base and acid. The pH-dependent conformational response was used to transduce a signal by appending to the binding site a 2-aminoisobutyric acid (Aib) oligomer, whose M or P helical conformation depended on the chirality of the bound ligand, and was reported by a remote 13C-labelled NMR reporter group. The multicomponent system thus converts a pH signal into a programmable conformational response which induces a remote spectroscopic effect.

8.
ChemistryOpen ; 9(3): 338-345, 2020 03.
Article in English | MEDLINE | ID: mdl-32195074

ABSTRACT

Two α-aminoisobutyric acid (Aib) foldamers bearing Zn(II)-chelating N-termini have been synthesized and compared with a reported Aib foldamer that has a bis(quinolinyl)/mono(pyridyl) cap (BQPA group). Replacement of the quinolinyl arms of the BQPA-capped foldamer with pyridyl gave a BPPA-capped foldamer, then further replacement of the linking pyridyl with a 1,2,3-triazole gave a BPTA-capped foldamer. Their ability to relay chiral information from carboxylate bound to Zn(II) at the N-terminus to a glycinamide-based NMR reporter of conformational preference at the C-terminus was measured. The importance of the quinolinyl arms became readily apparent, as the foldamers with pyridyl arms were unable to report on the presence of chiral carboxylate in acetonitrile. Low solubility, X-ray crystallography and 1H NMR spectroscopy suggested that interfoldamer interactions inhibited carboxylate binding. However changing solvent to methanol revealed that the end-to-end relay of chiral information could be observed for the Zn(II) complex of the BPTA-capped foldamer at low temperature.

9.
Chem Commun (Camb) ; 55(63): 9331-9334, 2019 Aug 14.
Article in English | MEDLINE | ID: mdl-31313773

ABSTRACT

A crystallographically characterised zinc(ii)-capped foldamer can sense the enantiomeric excess of scalemic carboxylate solutions, including those produced by enantioselective organocatalysis, and can relay this input signal along the foldamer body to a remote glycinamide group, which then provides an NMR spectroscopic output.

10.
Chem Commun (Camb) ; 53(78): 10768-10771, 2017 Sep 28.
Article in English | MEDLINE | ID: mdl-28875189

ABSTRACT

Conformationally mobile oligomers with helical structures, or 'dynamic foldamers', may populate a mixture of screw-sense conformers whose relative proportion has been used as a means of communicating information on a molecular scale. The dibenzazepinyl urea provides a means of quantifying both the sense and degree of this screw-sense preference through a combination of circular dichroism (CD) and NMR spectroscopy. The dibenzazepinyl urea probe is synthetically versatile, readily accessible, and easy to introduce to the terminus of an amide or a urea foldamer.

11.
Chem Sci ; 8(4): 3007-3018, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28451368

ABSTRACT

Helical oligomers of achiral monomers adopt domains of uniform screw sense, which are occasionally interrupted by screw-sense reversals. These rare, elusive, and fast-moving features have eluded detailed characterization. We now describe the structure and habits of a screw-sense reversal trapped within a fragment of a helical oligoamide foldamer of the achiral quaternary amino acid 2-aminoisobutyric acid (Aib). The reversal was enforced by compelling the amide oligomer to adopt a right-handed screw sense at one end and a left-handed screw sense at the other. The trapped reversal was characterized by X-ray crystallography, and its dynamic properties were monitored by NMR and circular dichroism, and modelled computationally. Raman spectroscopy indicated that a predominantly helical architecture was maintained despite the reversal. NMR and computational results indicated a stepwise shift from one screw sense to another on moving along the helical chain, indicating that in solution the reversal is not localised at a specific location, but is free to migrate across a number of residues. Analogous unconstrained screw-sense reversals that are free to move within a helical structure are likely to provide the mechanism by which comparable helical polymers and foldamers undergo screw-sense inversion.

12.
Chem Commun (Camb) ; 52(27): 4852-63, 2016 Apr 07.
Article in English | MEDLINE | ID: mdl-26955864

ABSTRACT

Foldamers can be made more than pieces of static, conformationally uniform molecular architecture by designing into their structure the conformational dynamism characteristic of functional molecular machines. We show that these dynamic foldamers display biomimetic properties reminiscent of allosteric proteins and receptor molecules. They can translate chemical signals into conformational changes, and hence into chemical outputs such as control of reactivity and selectivity. Future developments could see dynamic foldamers operating in the membrane phase providing artificial mechanisms for communication and control that integrate synthetic chemistry into synthetic biology.


Subject(s)
Molecular Conformation , Biomimetics , Magnetic Resonance Spectroscopy , Polymers/chemistry , Proteins/chemistry , Stereoisomerism
13.
Article in English | MEDLINE | ID: mdl-30766694

ABSTRACT

Canada's Generation X is now entering the menopausal transition and pursuing effective therapy for bothersome vasomotor symptoms. They do so at a time when confusion about the safe and appropriate use of menopausal hormone therapy (MHT) has never been greater. Misplaced fears among women and their health care providers about MHT have, in many circumstances, led them to abandon this most effective therapy. This review discusses the physiology of the menopausal transition, the nature of symptoms related to withdrawal of ovarian estrogen production, and the potential benefits and risks of MHT. It is now clear that for most recently menopausal women the benefits of MHT outweigh the risks. The rationale for choosing different dosages, formulations, and regimens is reviewed.

14.
Chem Commun (Camb) ; 51(59): 11802-5, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26107614

ABSTRACT

Linking together an oligourea and an oligoamide foldamer gives rise to a conformationally well-defined structure, despite the different hydrogen-bonding patterns in the two domains, provided the oligomers are ligated amide C terminus to urea N terminus. A powerful screw-sense preference induced at the N terminus of the resulting chimeric structure provides evidence for cooperative conformational interactions within the 'block co-foldamer'.


Subject(s)
Amides/chemistry , Urea/chemistry , Crystallography, X-Ray , Models, Molecular , Molecular Conformation , Urea/analogs & derivatives
15.
Chem Sci ; 6(4): 2313-2322, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-29308146

ABSTRACT

Although foldamers, by definition, are extended molecular structures with a well-defined conformation, minor conformers must be populated at least to some extent in solution. We present a quantitative analysis of these minor conformers for a series of helical oligomers built from achiral but helicogenic α-amino acids. By measuring the chain length dependence or chain position dependence of NMR or CD quantities that measure screw-sense preference in a helical oligomer, we quantify values for the decay constant of a conformational signal as it passes through the molecular structure. This conformational signal is a perturbation of the racemic mixture of M and P helices that such oligomers typically adopt by the inclusion of an N or C terminal chiral inducer. We show that decay constants may be very low (<1% signal loss per residue) in non-polar solvents, and we evaluate the increase in decay constant that results in polar solvents, at higher temperatures, and with more conformationally flexible residues such as Gly. Decay constants are independent of whether the signal originates from the N or the C terminus. By interpreting the decay constant in terms of the probability with which conformations containing a screw-sense reversal are populated, we quantify the populations of these alternative minor conformers within the overall ensemble of secondary structures adopted by the foldamer. We deduce helical persistence lengths for Aib polymers that allow us to show that in a non-polar solvent a peptide helix, even in the absence of chiral residues, may continue with the same screw sense for approximately 200 residues.

16.
J Clin Pathol ; 34(12): 1388-91, 1981 Dec.
Article in English | MEDLINE | ID: mdl-6276444

ABSTRACT

A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence.


Subject(s)
Antigens, Viral/analysis , Enzyme-Linked Immunosorbent Assay/methods , Feces/analysis , Immunoenzyme Techniques , Reoviridae/immunology , Rotavirus/immunology , Fluorescent Antibody Technique , Gastroenteritis/diagnosis , Humans , Infant , Microscopy, Electron , Reagent Kits, Diagnostic , Reoviridae Infections/diagnosis , Rotavirus/ultrastructure
17.
J Clin Pathol ; 27(8): 603-8, 1974 Aug.
Article in English | MEDLINE | ID: mdl-4138653

ABSTRACT

A method is described for examining viruses in faeces by direct electron microscopy using negative staining. The particles found in a group of patients with gastroenteritis and a group with other conditions are compared. Small particles in the range of sizes covering parvoviruses and enteroviruses were found about as frequently in each group. Many of these were probably bacteriophages. Many bacteriophages with tails of various sizes and lengths were found. Adenoviruses were found in five of eight patients from whom they were isolated. Reovirus- (or orbivirus-) like particles were found associated with some gastroenteritis patients.


Subject(s)
Feces/microbiology , Virus Diseases/diagnosis , Adenoviridae/isolation & purification , Bacteriophages/isolation & purification , Enterovirus/isolation & purification , Gastroenteritis/diagnosis , Gastroenteritis/microbiology , Humans , Methods , Microscopy, Electron , Parvoviridae/isolation & purification , Pseudomonas , Reoviridae/isolation & purification , Staining and Labeling , Virus Diseases/microbiology
18.
J Clin Pathol ; 27(8): 608-14, 1974 Aug.
Article in English | MEDLINE | ID: mdl-4214154

ABSTRACT

Virus particles resembling reoviruses or orbiviruses were found in the faeces of 40 of 73 patients under 6 years of age with acute gastroenteritis and in faeces of only two babies among 31 patients under 6 years admitted to hospital with other diagnoses. In morphology the particles resemble orbiviruses more closely than reoviruses, but differ in appearance from the orbiviruses in having a smooth, circular outline with a well marked continuous rim as seen in negatively stained preparations. They appear not to be serologically related to reovirus types 1, 2, or 3 and may be members of a new group.


Subject(s)
Gastroenteritis/microbiology , Reoviridae/isolation & purification , Acute Disease , Agglutination , Animals , Child , Child, Preschool , Culture Techniques , Feces/microbiology , Haplorhini , Humans , Immune Sera , Infant , Kidney/pathology , Microscopy, Electron , Reoviridae/classification
19.
J Clin Pathol ; 52(6): 471-4, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10562819

ABSTRACT

The aim of this project was to produce guidance for a rationalised virological electron microscopy specimen testing policy for PHLS North West, to facilitate centralisation of a groupwide diagnostic electron microscopy service on a single site. Careful specimen selection to limit numbers and the groupwide use of commercially available enzyme immunoassays has allowed PHLS North West to reduce the number of specimens prepared for electron microscopy. The rationalised virological electron microscopy specimen testing policy has enabled a diagnostic electron microscopy service to be provided from a single site with a manageable workload. Implementation of this specimen testing policy by PHLS North West has been successful and may be applicable to other laboratories (or groups of laboratories) to maximise the use of expensive electron microscopy facilities.


Subject(s)
Microscopy, Electron/standards , Virus Diseases/diagnosis , Aged , Child, Preschool , England , Feces/virology , Humans , Immunoenzyme Techniques , Infant , Laboratories, Hospital/standards , Skin/virology , Specimen Handling , Workload
20.
J Med Microbiol ; 10(1): 121-5, 1977 Feb.
Article in English | MEDLINE | ID: mdl-402472

ABSTRACT

Rotaviruses were detected by electronmicroscopy in 35 of 84 specimens of faeces from infants with diarrhoea, and in 31 by fluorescent staining of tissue cultures infected with help of centrifugation. LLC-MK2 cells were found to be the most sensitive, although primary and secondary human-embryo-kidney and primary calf-kidney cells could also be used. A micromodification of the tissue-culture method provides a relatively simple technique for the diagnosis of rotavirus infection, for the titration of virus infectivity and for estimating neutralising antibodies in serum.


Subject(s)
Diarrhea, Infantile/diagnosis , Virus Cultivation/methods , Virus Diseases/diagnosis , Viruses, Unclassified/isolation & purification , Animals , Cattle , Cell Line , Culture Techniques , Diagnosis, Differential , Feces/microbiology , Haplorhini , Humans , Infant
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