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Willis E, Watkins J. Influenza vaccination policy and high risk subjects. BMJ : BRITISH MEDICAL JOURNAL 1998. [DOI: 10.1136/bmj.317.7154.349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Bhavsar S, Watkins J, Young A. Synergy between amylin and cholecystokinin for inhibition of food intake in mice. Physiol Behav 1998; 64:557-61. [PMID: 9761232 DOI: 10.1016/s0031-9384(98)00110-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Several gastrointestinal peptides which are secreted in response to nutrients have been reported to suppress food intake. Amylin is a peptide hormone co-secreted with insulin from pancreatic beta-cells in response to nutrient stimuli. Cholesystokinin (CCK) is secreted from duodenal and jejunal mucosal cells in response to fat and protein. Amylin and CCK-8 have been reported to reduce food intake in rodents when given centrally as well as peripherally. Amylin injected intraperitoneally (i.p.) reduced food intake over the subsequent 30 min in overnight fasted mice by a maximum of 57 +/- 6% with an ED50 of 0.93 nmol/kg (3.63 microg/kg) +/- 0.34 log units. On a molar basis, this potency was similar to that of CCK-8 (ED50 0.85 nmol/kg (0.97 microg/kg) +/- 0.28 log units; p = 0.93) which inhibited food intake by a maximum of 71 +/- 7%. When amylin and CCK-8 were injected i.p. as an amylin:CCK-8 mixture, immediately before presentation of food in overnight fasted mice, food intake in the subsequent 30 min was reduced by a maximum of 91%, an amount that was greater than that producable by i.p. injection of amylin or CCK-8 alone. Isobolar analysis revealed a marked synergy between amylin and CCK-8 in reducing food intake, such that statistically ineffective doses of amylin and CCK, when combined, evoked near-maximal inhibition of food intake. Because the typical physiological event is for amylin and CCK both to be secreted in response to mixed meals, the synergy between them could indicate a shared role in physiological appetite control.
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Bryan S, Weatherburn G, Watkins J, Roddie M, Keen J, Muris N, Buxton MJ. Radiology report times: impact of picture archiving and communication systems. AJR Am J Roentgenol 1998; 170:1153-9. [PMID: 9574575 DOI: 10.2214/ajr.170.5.9574575] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE We investigated the impact on radiologist reporting time of the change from conventional film to hard-copy computerized radiography and of the subsequent move to soft-copy images on picture archiving and communication system (PACS) workstations. MATERIALS AND METHODS A controlled before and after research design was undertaken. Data were collected on four occasions: two relating to conventional film, one relating to hard-copy computerized radiography, and one relating to soft-copy PACS images. Data collection was by direct observation of radiology reporting sessions by independent health service researchers. Data were collected on report times, details of images viewed, characteristics of the radiologist, and details of interruptions. To control for potential biases in the before and after comparisons, ordinary least squares multiple regression analysis was used. The principal comparison was between reports with PACS and reports with computerized radiography hard-copy because no change was noted in the organization of the reporting process between these two data collection rounds other than the introduction of the PACS. RESULTS Data were collected on a total of 5568 report observations. Report time in the PACS data collection period was not significantly different (p = .32) than that in the computerized radiography hard-copy period. Reporting with the PACS was associated with significantly more (p < .01) historical images (i.e., images of the same patient obtained in previous examinations) being viewed. CONCLUSION Report time was not lengthened by the introduction of the PACS. The finding that more historical images were viewed when the PACS was in use indicates that the PACS brought about a positive change in reporting practice.
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Watkins J. Theoretical considerations concerning the effect of relativistic velocities on the rate of biological processes. AVIATION, SPACE, AND ENVIRONMENTAL MEDICINE 1998; 69:182; author reply 182-3. [PMID: 9491262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Munsterman KA, Grindon AJ, Sullivan MT, Trouern-Trend J, Blackmon MJ, Watkins J, Williams AE. Assessment of motivations for return donation among deferred blood donors. American Red Cross ARCNET Study Group. Transfusion 1998; 38:45-50. [PMID: 9482393 DOI: 10.1046/j.1537-2995.1998.38198141497.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The recent addition of a computerized donor deferral registry to American Red Cross blood donation procedures has enabled blood center staffs to identify, before donation, persons who attempt to donate despite previous deferral. The current study investigated reasons that deferred donors return to donate, despite having been notified that they are ineligible. STUDY DESIGN AND METHOD Anonymous mail surveys requesting demographic information, details of last donation or attempted donation, and assessments of incentives for donating were sent to 311 donors presenting inappropriately at blood drives and 849 matched controls in three American Red Cross regions between April and July 1996. RESULTS Responses were received from a total of 113 deferred donors and 388 matched controls. Analysis of the 49 permanently deferred donors indicated that they were more likely than controls to donate blood to receive test results or to be awarded community service credit. Responses also revealed that some deferred donors may return to donate blood because of a misunderstanding of the deferral message or erroneous recruitment by blood center staff. CONCLUSION There is a need before donation for the provision of educational materials regarding the window period of infection and for careful consideration of the use of incentives to attract donors to blood centers. It is also important to provide to donors a clear and consistent message regarding their test results and deferral status.
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Watkins J. Effectiveness of influenza vaccination policy at targeting patients at high risk of complications during winter 1994-5: cross sectional survey. BMJ (CLINICAL RESEARCH ED.) 1997; 315:1069-70. [PMID: 9366738 PMCID: PMC2127699 DOI: 10.1136/bmj.315.7115.1069] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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157
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Dunne R, Watkins J. Complementary medicine--some definitions. JOURNAL OF THE ROYAL SOCIETY OF HEALTH 1997; 117:287-91. [PMID: 9519660 DOI: 10.1177/146642409711700505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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158
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Weatherburn GC, Watkins J, Bryan S, Cocks R. The effect of PACS on the visualization of the lateral cervical spine and the management of patients presenting with trauma. MEDICAL INFORMATICS = MEDECINE ET INFORMATIQUE 1997; 22:359-68. [PMID: 9509406 DOI: 10.3109/14639239709010907] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In patients presenting with trauma, early diagnosis of neck injuries is likely to affect long-term outcome. This paper reports a study that compared lateral images of the cervical spine produced by a Picture Archiving and Communication System (PACS) with the same images produced using computed radiography (CR). The study was undertaken at the Hammersmith Hospital, London. Data were collected on 100 patients who presented with trauma. Both soft copy (PACS) and hard copy (CR) images of the cervical spine were produced for each patient from the same radiographic exposure. The images were viewed by five clinical members of the Accident and Emergency Department. Data were collected on the level of the cervical spine that could be viewed, the clinical management following the viewing of the image and the use of PACS 'tools'. Overall no statistically significant differences between modalities were found in the level of visualization. Within viewer differences were found for three viewers: one indicating better visualization with PACS and two indicating better visualization with CR. The results relating to patient management indicate greater clinician confidence following the viewing of PACS images for two viewers. The use of PACS 'tools' improved visualization of the cervical spine for one viewer.
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Watkins J, Davies GJ, Vinten G. Submitting a paper to the Society's Journal. JOURNAL OF THE ROYAL SOCIETY OF HEALTH 1997; 117:20-2. [PMID: 9050288 DOI: 10.1177/146642409711700106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Each Journal has its own specific requirements for authors dealing with matters such as type of papers published, instructions for their submission and their layout and content. Requirements of authors are printed on the back cover of each issue of the Journal of the Royal Society of Health. This paper explores these in more detail and updates them for 1997 and onwards.
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Abdulla AJ, Watkins J, Pearce V. Prevalence of Leg Cramps in the Elderly; Drug and Disease Associations. Age Ageing 1997. [DOI: 10.1093/ageing/26.suppl_1.p9-a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Maslow AD, Breen TW, Sarna MC, Soni AK, Watkins J, Oriol NE. Prevalence of coagulation abnormalities associated with intrauterine fetal death. Can J Anaesth 1996; 43:1237-43. [PMID: 8955974 DOI: 10.1007/bf03013432] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PURPOSE The purpose of this study was to determine factors associated with abnormal coagulation in the setting of intrauterine fetal death (IUFD). METHODS We reviewed the charts of 238 patients diagnosed with IUFD over ten years. Data included demographics, co-existing obstetric disease and coagulation studies. A coagulation score was assigned based on the platelet count, prothrombin time, activated partial thromboplastin time and plasma fibrinogen concentration. Approximately 90% of the study population had coagulation scores < 4. A score of > or = 4 was considered abnormal. RESULTS Complete coagulation analysis was available in 183/238 patients (77%) within 24 hr of delivery. One hundred and sixty-four of these (89.6%) had a coagulation score, < 4 and 19 had a score > or = 4 (10.4%). No relationship between the coagulation score and age, parity, gestational age at delivery, and number of days the dead fetus remained in utero was found. A coagulation score > = or 4 was associated with the presence of a pregnancy-related disease (P < 0.05), notably abruption (P < 0.001) and uterine perforation (P < 0.05). Four patients without co-existing disease (3.2%), had a coagulation score > or = 4. CONCLUSION In most pregnancies complicated by fetal demise, the fetus and placenta are delivered within one week of fetal demise. The previously reported severe coagulation disturbances are largely eliminated by early delivery. Our study shows that coagulation abnormalities occur in some patients with uncomplicated IUFDs (3.2%) and that this number rises in the presence of abruption or uterine perforation.
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Krupnick JL, Sotsky SM, Simmens S, Moyer J, Elkin I, Watkins J, Pilkonis PA. The role of the therapeutic alliance in psychotherapy and pharmacotherapy outcome: findings in the National Institute of Mental Health Treatment of Depression Collaborative Research Program. J Consult Clin Psychol 1996. [PMID: 8698947 DOI: 10.1037//0022-006x.64.3.532] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The relationship between therapeutic alliance and treatment outcome was examined for depressed outpatients who received interpersonal psychotherapy, cognitive-behavior therapy, imipramine with clinical management, or placebo with clinical management. Clinical raters scored videotapes of early, middle, and late therapy sessions for 225 cases (619 sessions). Outcome was assessed from patients' and clinical evaluators' perspectives and from depressive symptomatology. Therapeutic alliance was found to have a significant effect on clinical outcome for both psychotherapies and for active and placebo pharmacotherapy. Ratings of patient contribution to the alliance were significantly related to treatment outcome; ratings of therapist contribution to the alliance and outcome were not significantly linked. These results indicate that the therapeutic alliance is a common factor with significant influence on outcome.
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Maslow A, Comunale ME, Haering JM, Watkins J. Pulsed wave Doppler measurement of cardiac output from the right ventricular outflow tract. Anesth Analg 1996; 83:466-71. [PMID: 8780264 DOI: 10.1097/00000539-199609000-00004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Doppler ultrasound can be used to measure cardiac output (CO). Intraoperative Doppler cardiac output (DCO) by transesophageal echocardiography (TEE) has been studied using blood flow velocity from the left ventricular outflow tract (LVOT), the mitral valve (MV), and the main pulmonary artery (MPA). The purpose of this study was to compare DCO, measured from a relatively new TEE view of the right ventricular outflow tract (RVOT), with thermodilution cardiac output (TDCO). We also compared changes in DCO from the RVOT to changes in TDCO. A 5.0/3.7 MHz multiplane TEE probe was placed in 45 adult cardiac surgical patients undergoing general anesthesia. Patients were excluded if there was greater than mild tricuspid valve insufficiency. From the transgastric view, at approximately 110-140 degrees, the RVOT was imaged. DCO was calculated from 1) the time-velocity integral (TVI) using pulse wave (PW) Doppler, 2) the area of the RVOT (measured in early systole using the diameter (pi(D/2)2) of the RVOT at the level of the PW Doppler sample volume), and 3) the heart rate. Simultaneous TDCO was performed by a separate examiner. The RVOT was imaged satisfactorily in 84% of patients (38/45). The mean bias between DCO and TDCO was -0.01 L/min (2 SD +/- 0.45 L/min; n = 38). There was good correlation between DCO and TDCO (R2 = 0.97). Changes in TDCO and changes in DCO were compared in 15 patients. The mean bias between changes in DCO and changes in TDCO was 0.04 L/min (2 SD +/- 0.66 L/min). Analysis of the changes in DCO and TDCO showed good correlation (R2 = 0.96). We conclude that there is a good correlation between DCO measured from the RVOT and TDCO. This technique permits cardiac output measurement without the necessity of placing a pulmonary artery catheter, and it also provides a method of evaluating RVOT blood flow.
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164
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Hall AJ, Watkins J, Hiby L. The impact of the 1993 Braer oil spill on grey seals in Shetland. THE SCIENCE OF THE TOTAL ENVIRONMENT 1996; 186:119-125. [PMID: 8685704 DOI: 10.1016/0048-9697(96)05090-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Signs of acute respiratory distress were reported in moulting grey seals (Halichoerus grypus) hauled out on Lady's Holm, Shetland, following the Braer oil spill in January, 1993. Behavioural observations carried out between 16 January and 13 February 1993 showed that the proportion of animals exhibiting a discharge of nasal mucus was significantly higher than the proportion at a control site in the north (Papa Stour). The proportion of animals affected on Lady's Holm increased for up to one month following the spill. However, the time lag between exposure and peak response was approximately 30 days, longer than may be expected for an acute effect. The proportion of non-specific signs of respiratory distress in unexposed Shetland seals was assessed from observations made between 16 January and 25 January 1994. Symptoms similar to those seen in 1993 were also reported during this period, but the proportion of affected animals was higher in 1993. Symptoms were not observed at a grey seal moult site on the east coast of England in March 1993 and 1994. Grey seals moulting in Shetland during the time of the oil spill may have been acutely affected by exposure to hydrocarbons, but without sufficient baseline data on the occurrence of respiratory distress in grey seals it is difficult to determine the proportion attributable to other causes.
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165
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Watkins J. The BSE crisis. Vet Rec 1996; 139:22. [PMID: 8819293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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166
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Cooke F, Galasko G, Ramrakha V, Richards D, Rose A, Watkins J. Medical students in general practice: how do patients feel? Br J Gen Pract 1996; 46:361-2. [PMID: 8983256 PMCID: PMC1239669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND The General Medical Council has recommended that medical students should gain more experience in general practice. AIM The study set out to determine patients' reactions to the presence of medical students in general practice consultations. METHOD Patients attending a random sample of general practice surgeries completed a questionnaire following consultation with and without a medical student present in six general practices in the Oxford area. RESULTS The questionnaires were completed by 278 patients. Only eight (3%) of all respondents had negative responses to the presence of a medical student. Of those completing questionnaires following a teaching consultation, 107 (56%) felt positively about the presence of students, compared with 36 (41%) who had attended a nonteaching surgery. Only three patients (1%) felt the quality of the consultation to be impaired by the presence of a student, while 48 patients (17%) felt there to be some improvement. The majority felt that the sex of the student was unimportant, but significantly more female than male patients (17% versus 5%) felt that it made a difference. CONCLUSION Only a small proportion of patients object to the presence of a medical student in general practice consultations. A significant minority said that the presence of a student improves the consultation.
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Krupnick JL, Sotsky SM, Simmens S, Moyer J, Elkin I, Watkins J, Pilkonis PA. The role of the therapeutic alliance in psychotherapy and pharmacotherapy outcome: findings in the National Institute of Mental Health Treatment of Depression Collaborative Research Program. J Consult Clin Psychol 1996; 64:532-9. [PMID: 8698947 DOI: 10.1037/0022-006x.64.3.532] [Citation(s) in RCA: 371] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The relationship between therapeutic alliance and treatment outcome was examined for depressed outpatients who received interpersonal psychotherapy, cognitive-behavior therapy, imipramine with clinical management, or placebo with clinical management. Clinical raters scored videotapes of early, middle, and late therapy sessions for 225 cases (619 sessions). Outcome was assessed from patients' and clinical evaluators' perspectives and from depressive symptomatology. Therapeutic alliance was found to have a significant effect on clinical outcome for both psychotherapies and for active and placebo pharmacotherapy. Ratings of patient contribution to the alliance were significantly related to treatment outcome; ratings of therapist contribution to the alliance and outcome were not significantly linked. These results indicate that the therapeutic alliance is a common factor with significant influence on outcome.
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Watkins J. Acidogenecy of herbal baby drinks. Br Dent J 1996; 180:247. [PMID: 8935286 DOI: 10.1038/sj.bdj.4809042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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169
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Barnard A, Mahon BP, Watkins J, Redhead K, Mills KH. Th1/Th2 cell dichotomy in acquired immunity to Bordetella pertussis: variables in the in vivo priming and in vitro cytokine detection techniques affect the classification of T-cell subsets as Th1, Th2 or Th0. Immunology 1996; 87:372-80. [PMID: 8778021 PMCID: PMC1384104 DOI: 10.1046/j.1365-2567.1996.497560.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In studies of the mechanism of immunity to Bordetella pertussis in a murine respiratory infection model, we have previously demonstrated that natural infection of immunization with a whole cell vaccine induces a potent protective immune response, which is mediated by T-helper type-1 (Th1) cells. In contrast an acellular vaccine generates Th2 cells and is associated with delayed bacterial clearance following respiratory challenge. In the present study we have investigated the apparent Th1/Th2 cell dichotomy in acquired immunity and have examined the factors that affect their induction or detection. The cytokine profiles of B. pertussis-specific T cells in immune animals were determined using antigen-stimulated ex vivo spleen cells or CD4+ T-cell lines and clones established in the presence of interleukin-2 (IL-2) or IL-4. Antigen-specific T cells derived from mice immunized with the acellular vaccine were almost exclusively of the Th2 cell type. In contrast, T-cell lines and clones established following respiratory infection or immunization with the whole cell vaccine were predominantly of the Th1 type. However, a proportion of T cells from convalescent mice, especially when cultured in the presence of IL-4, secreted IL-4 and IL-5 with or without detectable IL-2 and interferon-gamma (IFN-gamma), suggesting that Th0 or Th2 cells were also primed during natural infection in vivo. Furthermore, when mice were assessed 6 months after infection, spleen cells produced significant levels of IL-4 and IL-5, which were not evident at 6 weeks. The route of immunization and the genetic background of the mice were also found to influence the preferential priming of Th1 cells, and this was directly related to the level of protection against respiratory or intracerebral (i.c.) challenge. Our findings underline the critical role of CD4+ Th1 cells in immunity to B. pertussis, but also demonstrate that a number of factors in the in vivo priming and in vitro restimulation can skew the apparent dominance of one Th cell type over another.
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170
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Watkins J, Peabody P. Sports injuries in children and adolescents treated at a sports injury clinic. J Sports Med Phys Fitness 1996; 36:43-8. [PMID: 8699837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study presents the results of a three-year (1989-1991) retrospective survey of sports injuries to children and adolescents (5-17 years of age) treated at a sports injuries clinic (Crystal Palace, London). Of the total of 394 injuries, 178 (45.2%) were to females and 216 (54.8%) were to males. In both females and males the frequency of injuries showed a unimodal relationship with increasing age; the peak frequency in females occurred at age 13-14 years and in males at age 15-16 years. Fifty per cent of the injuries (197) were acute, 49.5% (195) were chronic and 0.5% (2) were inconclusive in diagnosis. Most of the acute injuries were muscle/tendon/ligament sprains, strains or contusions (62%) whereas most of the chronic injuries affected articular cartilage, epiphyseal and apophyseal growth plates (53%). Injuries to knees and ankles accounted for 51% of all injuries. The sports responsible for most injuries were characterised by i) explosive and/or high speed movements and/or ii) physical contact with apparatus, equipment or other players.
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O'Brien JR, Etherington MD, Brant J, Watkins J. Decreased platelet function in aortic valve stenosis: high shear platelet activation then inactivation. Heart 1995; 74:641-4. [PMID: 8541170 PMCID: PMC484121 DOI: 10.1136/hrt.74.6.641] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE To elucidate the mechanism of the bleeding tendency observed in patients with aortic valve stenosis. DESIGN A prospective study of high and low shear platelet function tests in vitro in normal controls compared with that in patients with severe aortic valve stenosis with a mean (SD) systolic gradient by Doppler of 75 (18) mm Hg before and at least 4 months after aortic valve replacement. SETTING District general hospital. RESULTS The patients showed reduced retention in the high shear platelet function tests. (a) Platelet retention in the filter test was 53.6 (12.6)% in patients with aortic valve stenosis and 84.8 (9.6)% in the controls (P < 0.001). (b) Retention in the glass bead column test was 49.8 (19.2) in the patients and 87.4 (8.7) in the controls (P < 0.001). (c) The standard bleeding time was longer in the patients (P < 0.06). Results of the high shear tests (a, b, and c) after aortic valve replacement were within the normal range. The platelet count was low but within the normal range before surgery and increased postoperatively (P < 0.01). There were no differences in the results of standard clotting tests, plasma and intraplatelet von Willebrand's factor, or in 15 platelet aggregation tests using five agonists between patients with aortic valve stenosis and controls. CONCLUSIONS The high shear haemodynamics of aortic valve stenosis modify platelet function in vivo predisposing to a bleeding tendency. This abnormality of platelet function is detectable only in vitro using high shear tests. The abnormal function is reversed by aortic valve replacement. High shear forces in vitro activate and then inactivate platelets. By the same mechanisms aortic valve stenosis seems to lead to high shear damage in vivo, resulting in a clinically important bleeding tendency in some patients.
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Wood M, Watkins J, Caan W. Parameters of clinical supervision. BRITISH JOURNAL OF NURSING 1995; 4:1226. [PMID: 8696093 DOI: 10.12968/bjon.1995.4.20.1226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Watkins J. Adverse reaction to neuromuscular blockers: frequency, investigation, and epidemiology. ACTA ANAESTHESIOLOGICA SCANDINAVICA. SUPPLEMENTUM 1994; 102:6-10. [PMID: 7976160 DOI: 10.1111/j.1399-6576.1994.tb04030.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A survey is presented of neuromuscular drug involvement in 390 clinically severe anaphylactoid reactions (grades II-IV reported to a Sheffield laboratory from 1988 to the end of 1992 from hospitals throughout the UK. Despite advances in patient monitoring and newer drugs, the reporting frequency and individual drug involvement were remarkably similar to those of a previous report from the laboratory in 1988. The highly immunogenic drug suxamethonium still predominated (48% of reports), but there was now much reduced use of the similarly immunogenic drug, alcuronium. The incidence of reactions to vecuronium and atracurium remained similar (12% and 18% reports, respectively) and acceptable to the anaesthetist. However, in choosing drugs for individual patients, the anaesthetist may wish to note that vecuronium reactors mainly showed bronchospasm, and atracurium reactors hypotension. By a systematic laboratory investigation, based on measurement of plasma tryptase and urinary methylhistamine, reaction mechanisms were assessed in 53 reactions. Despite their overall clinical similarity, analysis revealed that only one reaction in three was likely to be due to IgE-mediated anaphylaxis (Type 1). Not only was suxamethonium the most frequently reported drug, but in this study 11 reactions were identified as Type 1 response: no allergic reactions were identified for either vecuronium or atracurium, although single cases were identified for alcuronium, gallamine, and tubocurarine, with two unidentified. The remaining reactions were judged to be non-immune, although most involved mast cell degranulation. These reactions were no less hazardous than Type 1 reactions (one death), and two deaths were recorded. The importance of laboratory investigation as a feature of postreaction care is emphasized.
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Redhead K, Sesardic D, Yost SE, Attwell AM, Watkins J, Hoy CS, Plumb JE, Corbel MJ. Combination of DTP and Haemophilus influenzae type b conjugate vaccines can affect laboratory evaluation of potency and immunogenicity. Biologicals 1994; 22:339-45. [PMID: 7779360 DOI: 10.1006/biol.1994.1052] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A commonly used Diphtheria-Tetanus-Pertussis (whole-cell) vaccine was combined with each of three different Haemophilus influenzae type b (Hib) capsular polysaccharide vaccines. Each Hib vaccine incorporated one of three different protein conjugates: tetanus toxoid, diphtheria CRM197 toxoid or group B Neisseria meningitidis outer membrane vesicles. The effects of these combinations on the subsequent laboratory control testing were examined. The addition of the Hib vaccines had no significant effect on the reactogenicity or the potency of the whole-cell pertussis component. The potency of, and antibody responses to, the diphtheria component were also unaffected in all three combinations. However, combination with the Hib vaccine comprising polysaccharide conjugated to tetanus toxoid had dramatic effects on tetanus potency and immunogenicity when assayed in mice. This combination resulted in a five-fold potentiation of the tetanus potency and a similarly large increase in the antibody responses to tetanus toxin and toxoid. The level of the antibody response to the Hib polysaccharide in this vaccine was also elevated, more than 20-fold, as a result of the combination. Such phenomena were not evident with combinations involving the other two Hib vaccines. These results have implications for the control testing of combined vaccines containing a whole-cell pertussis component and Hib polysaccharide-tetanus protein conjugate vaccine.
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Redhead K, Sesardic D, Yost SE, Attwell AM, Watkins J, Hoy CS, Plumb JE, Corbel MJ. Interaction of Haemophilus influenzae type b conjugate vaccines with diphtheria-tetanus-pertussis vaccine in control tests. Vaccine 1994; 12:1460-6. [PMID: 7887024 DOI: 10.1016/0264-410x(94)90156-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The effects of combining three Haemophilus influenzae type b (Hib) capsular polysaccharide vaccines, conjugated to different proteins, with DTP vaccine on the subsequent control testing were examined. The addition of the Hib vaccines had little effect on the reactogenicity or the potency of the whole-cell pertussis component. The potency of, and antibody responses to, the diphtheria component were also unaffected in all three combinations. However, combination with the Hib vaccine comprising polysaccharide conjugated to tetanus toxoid resulted in a fivefold potentiation of the tetanus potency and large increases in the antibody responses to tetanus toxin and toxoid and Hib polysaccharide. These results have implications for the control testing of combined vaccines containing a whole-cell pertussis component and Hib polysaccharide-tetanus protein conjugate vaccine.
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