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2. Development of techniques for the study of protein systems

Author

Hooper, R. J.

Subjects
572.8
Abstract

This dissertation descries work undertaken to investigate protein systems on nano- and micro-levels. The principal objective was the application of fluid dynamic gauging with simultaneous direct imaging of the changes in microstructure occurring during the cleaning of whey protein foulants. Laser confocal microscopy allowed images of the internal microstructure, on the micron and tens-of-microns scales, to be matched against the changing macro-properties of a whey protein film during cleaning, as measured by the gauge on the tens-of-microns scale. This work constitutes proof of concept; the successful capture of gauging and microscopy data displaying consistent, complementary phenomena proved the efficacy of the experimental concept. Achievement of this goal required first establishing the operating range within which use of the gauge caused minimal interference with the film being studied and, secondly, the development of a whey protein foulant that reproduced behavioural characteristics of fouling layers studied by previous researchers while also being suitable for microscopy. Both these objectives were achieved. That minimal interference range was established by comparing gauging cleaning profiles of particular deposits within duct flows against alternative cleaning profiles obtained by measuring the changing thermal resistances of the deposits. It was shown that the suitability of the operating regime was dependent on the capacity of the deposit to resist the suction pressure of the gauge. Stresses that exceed the cohesive and adhesive strengths of a deposit were used to explore in more detail the adhesive properties of foulant layers, using dried tomato purée as a model system. A quasi-stagnant system was used, in which the only flow present was that through the gauge. Thus the gauge was the source of all stresses imposed on the deposit by flow; this enabled accurate inference of the imposed normal stress.

Published
2006

4. Surgery for constipation: systematic review and clinical guidance: Paper 1: Introduction & Methods

Author

Knowles, C. H., Grossi, U., Horrocks, E. J., Pares, D., Vollebregt, P. F., Chapman, M., Brown, S. R., Mercer‐Jones, M., Williams, A. B., Hooper, R. J., Stevens, N., Mason, J., Campbell, Kenneth, Clarke, Andrew, Cruickshank, Neil, Dixon, Anthony, Emmett, Christopher, Lacy‐Colson, Jon, Lindsey, Ian, Miller, Andrew, Pilkington, Sophie, Smart, Neil, Tincello, Douglas, Telford, Karen, Yiannakou, Yan, Altomare, Donato, Boenicke, Lars, Buntzen, Steen, Campbell, Ken, Christensen, Peter, DʼHoore, Andre, Espin, Eloy, Jayne, David, Jones, Oliver, Knapp, Jens‐Christian, Laurberg, Soren, Lehur, Paul, Matzel, Klaus, OʼConnell, Ronan, Prudʼhomme, Michel, Ratto, Carlo, Trompetto, Mario, and Vaizey, Caroline

Published
2017
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5. Surgery for constipation: systematic review and practice recommendations: Graded practice and future research recommendations

Author

Knowles, C. H., Grossi, U., Horrocks, E. J., Pares, D., Vollebregt, P. F., Chapman, M., Brown, S., Mercer‐Jones, M., Williams, A. B., Yiannakou, Y., Hooper, R. J., Stevens, N., Mason, J., Campbell, Kenneth, Clarke, Andrew, Cruickshank, Neil, Dixon, Anthony, Emmett, Christopher, Lacy‐Colson, Jon, Lindsey, Ian, Miller, Andrew, Pilkington, Sophie, Smart, Neil, Tincello, Douglas, Telford, Karen, Altomare, Donato, Boenicke, Lars, Buntzen, Steen, Campbell, Ken, Christensen, Peter, DʼHoore, Andre, Espin, Eloy, Jayne, David, Jones, Oliver, Knapp, Jens‐Christian, Laurberg, Soren, Lehur, Paul, Matzel, Klaus, OʼConnell, Ronan, Prudhomme, Michel, Ratto, Carlo, Trompetto, Mario, and Vaizey, Carolynne

Published
2017
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8. Prediction and characterization of heat-affected zone formation in tin-bismuth alloys due to nickel-aluminum multilayer foil reaction.

Author

Hooper, R. J., Davis, C. G., Johns, P. M., Adams, D. P., Hirschfeld, D., Nino, J. C., and Manuel, M. V.

Subjects
*TIN alloys, *BISMUTH alloys, *NICKEL-aluminum alloys, *HEAT treatment, *MULTILAYERS, *CHEMICAL reactions, *NUMERICAL analysis
Abstract

Reactive multilayer foils have the potential to be used as local high intensity heat sources for a variety of applications. Most of the past research effort concerning these materials have focused on understanding the structure-property relationships of the foils that govern the energy released during a reaction. To improve the ability of researchers to more rapidly develop technologies based on reactive multilayer foils, a deeper and more predictive understanding of the relationship between the heat released from the foil and microstructural evolution in the neighboring materials is needed. This work describes the development of a numerical model for the purpose of predicting heat affected zone size in substrate materials. The model is experimentally validated using a commercially available Ni-Al multilayer foils and alloys from the Sn-Bi binary system. To accomplish this, phenomenological models for predicting the variation of physical properties (i.e., thermal conductivity, density, and heat capacity) with temperature and composition in the Sn-Bi system were utilized using literature data. [ABSTRACT FROM AUTHOR]

Published
2015
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11. Surgery for constipation:systematic review and clinical guidance: Paper 1: Introduction & Methods

Author

Knowles, C. H., Grossi, U., Horrocks, E. J., Pares, D., Vollebregt, P. F., Chapman, M., Brown, S. R., Mercer-Jones, M., Williams, A. B., Hooper, R. J., Stevens, N., Mason, J., Campbell, Kenneth, Clarke, Andrew, Cruickshank, Neil, Dixon, Anthony, Emmett, Christopher, Grossi, Ugo, Lacy-Colson, Jon, Lindsey, Ian, Miller, Andrew, Pilkington, Sophie, Smart, Neil, Tincello, Douglas, and Telford, Karen

Subjects
Research design, medicine.medical_specialty, Constipation, Best practice, Psychological intervention, obstructed defaecation, surgery, Bias, Chronic Disease, Evidence-Based Medicine, Humans, Research Design, Review Literature as Topic, 03 medical and health sciences, 0302 clinical medicine, medicine, 030212 general & internal medicine, Chronic constipation, business.industry, Gastroenterology, Evidence-based medicine, Perioperative, Surgery, Systematic review, 030211 gastroenterology & hepatology, medicine.symptom, business, RD, RC
Abstract

Aim\ud \ud This manuscript provides the introduction and detailed methodology used in subsequent reviews to assess the outcomes of surgical interventions with the primary intent of treating chronic constipation in adults and to develop recommendations for practice.\ud \ud Method\ud \ud PRISMA guidance was adhered to throughout. A literature search was performed in public databases between January 1960 and February 2016. Studies that fulfilled strictly-defined PICOS (patients, interventions, controls, outcome, and study design) criteria were included. The process involved two groups of participants: (i): ‘a clinical guidance group’ of 18 UK experts (including junior support) who performed the systematic reviews and produced summary evidence statements (SES) based strictly on data synthesis in each review. The same group then produced prototype graded practice recommendations (GPRs) based on coalescence of SES and expert opinion; (ii): a European Consensus group of 18 ESCP (European Society of Coloproctology) nominated experts from nine European countries evaluated the appropriateness of each prototype GPR based on published RAND/UCLA methodology.\ud \ud Results\ud \ud An overview of the search results is provided in this manuscript. A total of 156 studies from 307 full text articles (from 2551 initially screened records) were included, providing data on procedures characterized by: (i) colonic resection (n = 40); (ii) rectal suspension (n = 18); (iii) rectal wall excision (n = 44); (iv) rectovaginal septum reinforcement (n = 47); (v) sacral nerve stimulation (n = 7). The overall quality of evidence was poor with 113/156 (72.4%) studies providing only Oxford level IV evidence. The best evidence was extracted for rectal excisional procedures, where the majority of studies were Oxford level I or II. The five subsequent reviews provide a total of 99 SES (reflecting perioperative variables, efficacy, harms and prognostic variables) that contributed to 100 prototype GPRs covering patient selection, procedural considerations and patient counselling. The final manuscript details the 85/100 GPRs that were deemed appropriate by European Consensus (remaining 15 were all uncertain) and future research recommendations.\ud \ud Conclusion\ud \ud This manuscript and the following 6 papers suggest that the evidence base for surgical management of chronic constipation is currently poor although some expert consensus exists on best practice. Further studies are required to inform future commissioning of treatments and of research funding.

Published
2017
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29. CHANGES IN THE CONCENTRATION OF 5-METHOXYTRYPTOPHOL IN THE CIRCULATION AT DIFFERENT PHASES OF THE HUMAN MENSTRUAL CYCLE

Author

HOOPER, R. J. L., SILMAN, R. E., LEONE, R. M., FINNIE, M. D. A., CARTER, S. J., GRUDZINSKAS, J. G., GORDON, Y. B., HOLLAND, DIANE T., CHARD, T., MULLEN, P. E., and SMITH, I.

Abstract

The pineal indole 5-methoxytryptophol (ML) has been shown to have an antigonadal activity when administered to experimental animals, but data on its normal pattern of secretion have been lacking. Using a new gas chromatography–mass spectrometry assay, the concentration of ML at various phases of the human menstrual cycle has been studied. Daily samples were obtained throughout the month from five women with a normal cycle and two women taking an oral contraceptive. In women with a normal cycle levels of ML were found to be significantly lower in the last third of their cycle; this change was not seen in women taking an oral contraceptive who had low levels throughout the month. The changes in concentration of ML did not correlate with the changes in concentration of gonadotrophins.

Published
1979
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30. CONCENTRATION OF 5-METHOXYTRYPTOPHOL IN PINEAL GLAND AND PLASMA OF THE RAT

Author

CARTER, S. J., LAUD, C. A., SMITH, I., LEONE, R. M., HOOPER, R. J. L., SILMAN, R. E., FINNIE, M. D. A., MULLEN, P. E., and LARSON-CARTER, D. L.

Abstract

5-Methoxytryptophol, a serotonin metabolite, was measured by gas chromatography–mass spectrometry in pineal glands, plasma and control tissues (cerebral cortex and salivary glands) from male rats kept in a controlled lighting environment. In the pineal gland the level of 5-methoxytryptophol was significantly higher during the dark period than during the light, the absolute levels being an order of magnitude less than those of melatonin. In the plasma, the levels showed a reverse situation with respect to lighting conditions. No correlation was found between the 5-methoxytryptophol levels in plasma and the pineal gland in individual animals. These results suggest that there is no obvious correlation between pineal content and pineal activity. This may be due to a combination of rapid turnover, secretion and/or peripheral conversion of another 5-methoxyindole to 5-methoxytryptophol.

Published
1979
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31. A SENSITIVE AND SPECIFIC ASSAY FOR 5-METHOXYTRYPTOPHOL IN PLASMA

Author

LEONE, R. M., SILMAN, R. E., HOOPER, R. J. L., FINNIE, M. D. A., CARTER, S. J., EDWARDS, R., SMITH, I., TOWELL, P., and MULLEN, P. E.

Abstract

5-Methoxytryptophol (ML) is found in the pineal gland and is known to have biological activity especially as an antigonadotrophic agent, but methods have been lacking for its measurement in the circulation. A gas chromatography–mass spectrometry assay using a trimethylsilyl derivative has been developed for the routine measurement of ML in plasma. The assay is of great specificity and has a sensitivity of 20 pmol/l. Studies on the levels of pineal indoles in the circulation, however, have been hampered by the possibility that extraneous compounds are being cross-measured. Thus the specificity of the routine assay has been further validated by comparing it with an alternative assay system where all the major parameters were changed, i.e. derivatizing reagent, internal standard and mass number. Results that were obtained using both assay systems were closely comparable.

Published
1979
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32. IMMEDIATE RESPONSE OF 5-METHOXYTRYPTOPHOL IN THE CIRCULATION TO HYPOGLYCAEMIC STRESS INDUCED BY INSULIN

Author

HOOPER, R. J. L., SILMAN, R. E., LEONE, R. M., FINNIE, M. D. A., CARTER, S. J., SAVAGE, M., PREECE, M., SMITH, I., and MULLEN, P. E.

Abstract

Pineal indoles have been shown to affect the release of anterior pituitary hormones but details of the interrelationships are lacking. Using a new gas chromatography–mass spectrometry (g.c.–m.s.) assay the concentration of 5-methoxytryptophol (ML) was measured in plasma samples obtained from 16 children undergoing investigation of pituitary function for delayed growth. All the children received an insulin tolerance test (ITT) to study their endocrine response to stress. Some children received luteinizing hormone releasing hormone (LH-RH) and/or thyrotrophin releasing hormone (TRH). The change in concentration of ML during an ITT was similar to the change in concentration of blood sugar; a drop at 20 min followed by a rise at 30 min. This was not significantly altered by the administration of LH-RH or TRH, nor was there a different pattern of response in children who were deficient in growth hormone as opposed to those with idiopathic delayed growth. The fall in concentration of ML with stress may mediate the increased secretion of pituitary hormones. Alternatively, the pineal gland may respond directly to insulin.

Published
1979
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33. Surgery for constipation: systematic review and practice recommendations: Graded practice and future research recommendations

Author

Knowles, C. H., Grossi, U., Horrocks, E. J., Pares, D., Vollebregt, P. F., Chapman, M., Brown, S., Mercer-Jones, M., Williams, A. B., Yiannakou, Y., Hooper, R. J., Stevens, N., Mason, J., Campbell, K., Clarke, A., Cruickshank, N., Dixon, A., Emmett, C., Lacy-Colson, J., Lindsey, I., Miller, A., Pilkington, S., Smart, N., Tincello, D., Telford, K., Altomare, D., Boenicke, L., Buntzen, S., Christensen, P., D'Hoore, A., Espin, E., Jayne, D., Jones, O., Knapp, J. -C., Laurberg, S., Lehur, P., Matzel, K., O'Connell, R., Prudhomme, M., Ratto, C., Trompetto, M., and Vaizey, C.

Subjects
medicine.medical_specialty, Biomedical Research, Consensus, Constipation, surgery, 03 medical and health sciences, 0302 clinical medicine, medicine, Humans, 030212 general & internal medicine, obstructed defaecation, Digestive System Surgical Procedures, Evidence-Based Medicine, business.industry, Patient Selection, Gastroenterology, Level iv, Guideline, Surgery, Systematic review, Chronic Disease, Practice Guidelines as Topic, 030211 gastroenterology & hepatology, medicine.symptom, RG, business, RC
Abstract

Aim\ud \ud This manuscript forms the final of seven that address the surgical management of chronic constipation (CC) in adults. The content coalesces results from the five systematic reviews that precede it and of the European Consensus process to derive graded practice recommendations (GPR).\ud Methods\ud \ud Summary of review data, development of GPR and future research recommendations as outlined in detail in the ‘introduction and methods’ paper.\ud Results\ud \ud The overall quality of data in the five reviews was poor with 113/156(72.4%) of included studies providing only level IV evidence and only four included level I RCTs. Coalescence of data from the five procedural classes revealed that few firm conclusions could be drawn regarding procedural choice or patient selection: no single procedure dominated in addressing dynamic structural abnormalities of the anorectum and pelvic floor with each having similar overall efficacy. Of one hundred ‘prototype’ GPRs developed by the clinical guideline group, 85/100 were deemed ‘appropriate’ based on the independent scoring of a panel of 18 European experts and use of RAND-UCLA consensus methodology. The remaining 15 were all deemed uncertain. Future research recommendations included some potential RCTs but also a strong emphasis on delivery of large multinational high-quality prospective cohort studies.\ud Conclusion\ud \ud While the evidence base for surgery in CC is poor, the widespread European consensus for GPRs is encouraging. Professional bodies have the opportunity to build on this work by supporting the efforts of their membership to help convert the documented recommendations into clinical guidelines.

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46. Trade-offs between social behaviour and foraging by sheep in heterogeneous pastures.

Author

Sibbald AM and Hooper RJ

Abstract

In heterogeneous pastures, groups of sheep may have to alter their social behaviour in order to graze patches of preferred vegetation. In this event, patch size, inter-patch distance and the contrast between patch and background vegetation are likely to affect behaviour. In this experiment, groups of five female Scottish Blackface sheep grazed for 2-h periods in 0.1ha grass plots containing seven 1.5mx1.5m patches of improved vegetation, with inter-patch distances of 1.5, 6 or 11.5m. Background vegetation was of either medium or poor quality. Control plots contained no patches. On average, sheep spent 44% of the time grazing patches, although patches comprised only 1.6% of the total plot area. Inter-patch distance did not affect accumulated time spent grazing patches during the first 30min, but patch residence time and the number of sheep on a patch increased with inter-patch distance. The distribution of nearest neighbour distances was altered when patches were 6 or 11.5m apart, compared to no patches. Accumulated time spent grazing patches and the number of sheep on a patch were greater with poor than medium backgrounds. Sheep visited patches frequently and for short periods and it is suggested that sheep often moved off patches as a result of competition. The results provide evidence that sheep make trade-offs between social and foraging behaviour and demonstrate the importance of interactions between social spacing and the size and spacing of vegetation patches, when sheep forage in heterogeneous pastures.

Published
2003
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47. Clinical case-based multimedia tutorials as a solution to some problems facing medical education.

Author

Hooper RJ, O'Connor J, and Cheesmar R

Subjects
CD-ROM, Curriculum, Problem Solving, Computer-Assisted Instruction, Education, Medical methods
Abstract

Medical education faces many challenges as curricula become crowded and teacher numbers fall. In addition, there are moves to reduce factual overload and to concentrate more on pathophysiological principles illustrated by relevant clinical cases. We describe one means of addressing these problems, using computer-aided learning programs which are based on clinical cases, are interactive and which incorporate multimedia elements. These CD-ROM programs include student assessments, a resource of background material and support self-managed and distance learning.

Published
1998
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48. Racial variation in serum creatine kinase unrelated to lean body mass.

Author

Worrall JG, Phongsathorn V, Hooper RJ, and Paice EW

Subjects
Adult, Body Mass Index, Female, Humans, Male, Black People, Body Composition, Creatine Kinase blood, White People
Abstract

In a group of 30 black and 30 white healthy workers, matched for age, sex and body weight, serum creatine kinase was significantly higher in black males than in white males (P less than 0.01). Seventeen blacks but only four whites had levels above the accepted upper limit of normal of 195 IU/l. There was no correlation with lean body mass. Elevation of serum creatine kinase need not signify disease in blacks, for whom a separate reference range should be established. Two cases are reported of physically healthy black men subjected to unnecessary investigation on the basis of persistently elevated serum creatine kinase.

Published
1990
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