24 results on '"Humphreys JD"'
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2. DISCUSSION. COLLIERY SPOIL TIPS - AFTER ABERFAN. (ORIGINAL PAPER PUBLISHED AS A SEPARATE DOCUMENT - LOAN COPIES AT 7598).
- Author
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RODIN, S, HARDING, SIR H, CROSTHWAITE, CD, BRIGGS, WR, CORBETT, BO, COCHRANE, NJ, FINEY, JT, BISHOP, AW, HUMPHREYS, JD, WEEKET, PG, DEE, PK, BROWN, RL, VAUGHAN, PR, MUIR WOOD, AM, and TAYLOR, RK
- Published
- 1973
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3. DISCUSSION. OBSERVED AND PREDICTED DEFORMATIONS IN A LARGE EMBANKMENT DAM DURING CONSTRUCTION.
- Author
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HUMPHREYS, JD, GOSSCHALK, EM, GIBSON, RE, NAYLOR, DJ, JOLLANS, LVM, BURLAND, JB, KENNARD, MF, LOW, WI, CHARLES, JA, WINDER, AJH, SMITH, IM, LITTLE, AL, PENMAN, ADM, CARLYLE, WJ, BISHOP, AW, BROMHEAD, E, and PYRAH, IC
- Published
- 1972
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4. Living Without a Diagnosis: A Patient's Perspective on Diabetic Macular Ischemia.
- Author
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Humphreys JD and Sivaprasad S
- Abstract
Diabetic macular ischemia (DMI) is a common complication of diabetic retinopathy (DR) that can result in progressive and irreversible vision loss. DMI is associated with damage in the vessels that supply blood to the retina and the enlargement of the foveal avascular zone. Currently, there are no approved treatments specifically for DMI. Furthermore, there is limited published information about the prognosis, prevalence or outcomes of DMI, and there is no consensus regarding diagnostic criteria. It is vital to ensure that there is sufficient, accessible and accurate information available to support patients, caregivers and physicians. To lay the foundation for more research into DMI and its impact on patients, we (a patient with DMI and an expert ophthalmologist) have worked together to interweave our personal perspectives and clinical experiences with a review of currently available literature on DMI. The development of a set of confirmed diagnostic criteria for DMI would assist both patients and physicians, allowing patients to access validated information about their condition and supporting the development of clinical trials for treatments of DMI. Training for physicians must continue to emphasise the importance of treating a patient holistically, rather than only treating their symptoms. Most importantly, developing trust and a healthy rapport between a patient and their physician is important in managing health anxiety and ensuring adherence to beneficial treatments or lifestyle adjustments; physicians must cultivate an open and flexible management approach with their patients. Finally, holistic educational programmes for patients, physicians and the general public around DMI and how it can affect daily functioning would facilitate general understanding and disease awareness., (© 2022. The Author(s).)
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- 2022
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5. Enhancing electrocardiographic analysis by combining a high-resolution 12-lead ECG with novel software tools.
- Author
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Barcos JC, Humphreys JD, Tello Santacruz IA, Guzman JP, Fernández Recalde ML, Avaca HA, and Cáceres Monié CR
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- Electrodes, Humans, Software, Artificial Intelligence, Electrocardiography methods
- Abstract
Introduction: Signal-averaged electrocardiography is a non-invasive, computerized technique that amplifies, filters, and averages cardiac electrical signals reducing contaminating noise to obtain a high-resolution record. The most widely used signal averaging (SA) method involves a bipolar X, Y, and Z orthogonal lead system. Information is limited regarding its application in the standard resting 12-lead ECG. A novel system combining a high-resolution 12-lead ECG (HR-ECG) registered by SA with advanced analysis tools is presented., History: Original programming of a commercially available signal-averaged HR-ECG device was modified, introducing more exhaustive electrocardiographic assessment instruments., Description: Using SA techniques and placing surface electrodes in the standard 12-lead ECG positions, a HR-ECG is acquired within a bandwidth of 0.25 to 262 Hz at a rate of 1000 samples per second. It is advisable to average at least 200 cycles, taking three to five minutes to record. The package includes different optional high-frequency filters, manual calipers, zoom/superimposing/amplification functions., Clinical Role: The main strength lies in obtaining a low noise HR-ECG with zooming capabilities without definition loss. Other potential advantages are the greater ease in performing high precision analysis and comparing different ECG leads simultaneously., Current Problems: The primary limitation is the inability to document intermittent or dynamic electrocardiographic disorders because of averaging similar electrical cardiac cycles., Future Developments: Adding artificial intelligence and further refinements in the averaging process could lead to software upgrades., Conclusion: Integrating HR-ECG, obtained through SA techniques, with novel advanced analysis tools can enhance the ability to detect electrocardiographic disorders of permanent expression expeditiously., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021 Elsevier Inc. All rights reserved.)
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- 2022
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6. Brugada phenocopy induced by severe pneumothorax.
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Barcos JC, Tello Santacruz IA, Monié CC, Fernández Recalde ML, and Humphreys JD
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- Aged, Drainage, Electrocardiography, Female, Humans, Pneumothorax therapy, Brugada Syndrome etiology, Pneumothorax complications
- Abstract
A Brugada phenocopy has been defined as a clinical situation that presents with an abnormal electrocardiogram identical to any of the electrocardiographic patterns found in Brugada syndrome in the absence of the characteristic congenital genetic abnormalities. The first confirmed case of type 1 Brugada phenocopy associated with severe left pneumothorax is presented. A provocative test with ajmaline, which proved to be negative, was performed to confirm the diagnosis. The presence of ST-segment elevation in the context of pneumothorax is most infrequent., (Copyright © 2017 Elsevier Inc. All rights reserved.)
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- 2018
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7. [Paul Hamilton Wood: the foremost British clinical cardiologist of the 20th century].
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Humphreys JD and Young P
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- Heart Defects, Congenital history, History, 20th Century, Rheumatic Heart Disease history, United Kingdom, Cardiology history
- Abstract
In the United Kingdom, during the mid-20th century, Paul Wood appears as the new leader of European cardiology. He introduced rigorous bed-side diagnostic methods and the confirmation of these clinical findings by cardiac catheterization, in an effort to demonstrate the pathophysiological causes of cardiac disease. In his search for the correct diagnosis, his comments, which could be caustic, both impressed and offended many. He had a strong commanding personality and was intensely honest in his appreciations. His showmanship and diagnostic ability became renown. In 1950, the publishing of the first edition of his textbook "Diseases of the Heart and Circulation" brought him worldwide recognition. In this book, Wood introduces his personal fresh style of narrative and his physiologic approach to cardiology. His intense professional activity, teaching, lecturing and preparing the third edition of his book, plus the fact that he was a heavy smoker, must have been the factors that lead to a myocardial infarction and death at the early age of 54. As Paul Dudley White and Ignacio Chávez in America, Paul Wood in Europe will be remembered as the emblematic figure leading the transition of cardiology into the modern era.
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- 2012
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8. Coin rotation task (CRT): a new test of motor dexterity.
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Mendoza JE, Apostolos GT, Humphreys JD, Hanna-Pladdy B, and O'Bryant SE
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- Adult, Aged, Brain Diseases physiopathology, Case-Control Studies, Cerebrum pathology, Cerebrum physiopathology, Fingers physiology, Fingers physiopathology, Functional Laterality, Humans, Male, Middle Aged, Sensitivity and Specificity, Brain Diseases diagnosis, Motor Skills physiology
- Abstract
Coin-rotation task (CRT), a measure of rapid, coordinated finger movements, was devised as a convenient, easily administered bedside test of motor dexterity; however, very little psychometric data exist regarding this task. The current project was undertaken to (a) provide preliminary normative data, (b) examine the convergent and discriminant validity of the task when compared with other standardized motor measures, and (c) examine the diagnostic accuracy of the CRT. The sample of 86 male participants included 60 controls and 26 patients with unilateral lesions of the left (n = 13) and right (n = 13) hemispheres. The CRT was not significantly correlated with age or education; non-adjusted left- and right-hand normative data are provided. The CRT demonstrated good convergent and divergent validity when compared with other standardized motor measures. The CRT was successful in differentiating control and brain damaged groups with mild motor impairment, and demonstrated an overall classification rate of 84.9%. Levels of sensitivity and specificity of the CRT were comparable with or better than other standardized tests of manual dexterity. The CRT offers a valid, quick, and convenient bedside measure of subtle motor impairment.
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- 2009
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9. Detecting dementia with the mini-mental state examination in highly educated individuals.
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O'Bryant SE, Humphreys JD, Smith GE, Ivnik RJ, Graff-Radford NR, Petersen RC, and Lucas JA
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- Aged, Aged, 80 and over, Brief Psychiatric Rating Scale standards, Educational Status, Female, Humans, Male, Mental Status Schedule standards, Registries standards, Sensitivity and Specificity, Dementia diagnosis, Dementia psychology, Neuropsychological Tests standards
- Abstract
Objective: To evaluate the utility of Mini-Mental State Examination (MMSE) scores in detecting cognitive dysfunction in a sample of highly educated individuals., Design: Archival data were reviewed on 4248 participants enrolled in the Mayo Clinic Alzheimer Disease Research Center and Alzheimer Disease Patient Registry., Patients: A total of 1141 primarily white (93%) individuals with 16 or more years of self-reported education were identified. These included 307 (164 men and 143 women) patients with dementia (any type), 176 (106 men and 70 women) patients with mild cognitive impairment, and 658 (242 men and 416 women) control participants without dementia., Setting: Mayo Clinic Alzheimer Disease Research Center and Alzheimer Disease Patient Registry cohort., Main Outcome Measures: Diagnostic accuracy estimates (sensitivity, specificity, and positive and negative predictive power) of MMSE cut scores in detecting cognitive dysfunction., Results: In this sample of highly educated, largely white older adults, the standard MMSE cut score of 24 (23 or below) yielded a sensitivity of 0.66, a specificity of 0.99, and an overall correct classification rate of 89% in detecting dementia. A cut score of up to 27 (26 or below) resulted in an optimal balance of sensitivity and specificity (0.89 and 0.91, respectively) with an overall correct classification rate of 90%. In a cognitively impaired group (dementia and mild cognitive impairment), a cut score of 27 (sensitivity, 0.69; specificity, 0.91) or 28 (sensitivity and specificity, 0.78) might be more appropriate., Conclusion: Older patients with a college education who present with complaints of cognitive decline (reported by themselves or others) and score less than 27 on the MMSE are at a greater risk of being diagnosed with dementia and should be referred for a comprehensive dementia evaluation, including formal neuropsychological testing.
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- 2008
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10. The quantification of fingerprint quality using a relative contrast index.
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Humphreys JD, Porter G, and Bell M
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- Adult, Algorithms, Amido Black, Coloring Agents, Female, Fiber Optic Technology, Humans, Indicators and Reagents, Male, Microscopy, Ninhydrin, Spectrophotometry, Dermatoglyphics
- Abstract
Research into fingermark enhancement techniques has traditionally used visual comparisons and qualitative methods to assess their effectiveness based on the quality of the developed fingermark. However, with increasing research into the optimisation of these techniques the need for a quantitative evaluative method has arisen. Parameters for acceptable fingerprint quality are not well defined and generally encompass clear, sharp edges and high levels of contrast between the fingermark ridges and background material. Using these current parameters, a conclusive measurement of fingerprint quality and thus the effectiveness of development techniques cannot be achieved. This study presents a model through which an aspect of fingerprint quality can be objectively and impartially measured based on a relative contrast index, constructed through measuring the reflective intensity of the fingermark ridges against the background material. Using a fibre-optic spectrophotometer attached to a microscope with axial illumination, the intensity counts of the ridge detail and background material were measured and a logarithmic contrast index constructed. The microscope and spectrophotometer parameters were experimentally tested using a standard colour resolution chart with known reflective properties. The protocol was successfully applied to four sample groups: black inked fingerprints on white paper; latent fingermarks on white paper developed separately with ninhydrin and physical developer; and fingermarks in blood deposited on white tiles and enhanced with amido black. The contrast indices obtained quantitatively reflect the level of contrast and provide an indication of fingerprint quality through a numerical representation rather than previous qualitative methods. It has been suggested that the proposed method of fingerprint quantification may be viable for application in the forensic research arena as it allows the definitive measurement of contrast to aid the evaluation of fingermark detection and enhancement techniques.
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- 2008
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11. Clinical utility of Trial 1 of the Test of Memory Malingering (TOMM).
- Author
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O'Bryant SE, Gavett BE, McCaffrey RJ, O'Jile JR, Huerkamp JK, Smitherman TA, and Humphreys JD
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- Aged, Case-Control Studies, Female, Humans, Male, Middle Aged, Retrospective Studies, Malingering diagnosis, Memory Disorders diagnosis, Neuropsychological Tests
- Abstract
The clinical utility of Trial 1 of the Test of Memory Malingering (TOMM) has recently become a topic of investigation. The current study cross-validated previous research suggesting that those participants who score 45 or greater on Trial 1 of the TOMM will continue to do so on Trial 2 and the Retention Trial and extended these findings to broader clinical and nonclinical populations. Two archival samples were included for analyses: one sample of healthy community-dwelling elders and another sample drawn from an outpatient neuropsychology clinic. As demonstrated previously, 100% of those patients that scored 45 or greater on TOMM Trial 1 scored above cut-scores on Trial 2 and the Retention Trial, supporting the utility of a possible discontinuation rule on Trial 1. When combined with previous research, the current results provide further support for the clinical utility of Trial 1 in predicting overall performance on the TOMM; however, use of any nonstandard administration of the TOMM may not satisfy Daubert criteria in forensic settings and may not be appropriate.
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- 2008
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12. Obsessive-compulsive disorder and romantic functioning.
- Author
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Abbey RD, Clopton JR, and Humphreys JD
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- Adolescent, Adult, Age Factors, Data Collection, Female, Humans, Libido, Male, Middle Aged, Obsessive-Compulsive Disorder diagnosis, Personal Satisfaction, Personality Inventory, Psychiatric Status Rating Scales, Research Design, Self Disclosure, Severity of Illness Index, Sexual Behavior psychology, Social Behavior, Surveys and Questionnaires, Interpersonal Relations, Love, Obsessive-Compulsive Disorder psychology
- Abstract
The current study examined the romantic relationships of individuals with obsessive-compulsive disorder (OCD). Participants were 64 individuals recruited from a national conference who completed measures of OCD symptoms, depressive symptoms, intimacy, self-disclosure, relationship satisfaction, and relationship worry. Severity of obsessions was negatively correlated with intimacy, relationship satisfaction, and self-disclosure. In contrast, two compulsive behaviors (washing and neutralizing) were positively correlated with several relationship variables. Fears of contamination from sexual activity were positively correlated with the severity of OCD symptoms. The clinical implications of the findings from this study and suggestions for future research are presented.
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- 2007
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13. Disordered eating behavior and obsessive compulsive symptoms in college students: cognitive and affective similarities.
- Author
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Humphreys JD, Clopton JR, and Reich DA
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- Adolescent, Adult, Cognition Disorders diagnosis, Culture, Feeding and Eating Disorders diagnosis, Female, Humans, Mood Disorders diagnosis, Obsessive-Compulsive Disorder diagnosis, Surveys and Questionnaires, Cognition Disorders epidemiology, Feeding and Eating Disorders epidemiology, Mood Disorders epidemiology, Obsessive-Compulsive Disorder epidemiology, Students statistics & numerical data, Universities
- Abstract
Few studies have examined the psychological similarities between disordered eating behavior and obsessive-compulsive (OC) symptoms. The present study examined relationships among disordered eating, OC symptoms, and three cognitive and affective variables (perfectionism, obsessive beliefs, and negative affect). The cognitive and affective variables were significantly associated with disordered eating and with OC symptoms in a sample of 160 college women. Results also indicated that perfectionism is an important link between disordered eating behavior and OC symptoms, although the nature of perfectionism differs somewhat for the two types of behavior. Implications of the current results and directions for future research are discussed.
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- 2007
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14. The influence of ethnicity on Symbol Digit Modalities Test performance: an analysis of a multi-ethnic college and hepatitis C patient sample.
- Author
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O'Bryant SE, Humphreys JD, Bauer L, McCaffrey RJ, and Hilsabeck RC
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- Adolescent, Adult, Analysis of Variance, Female, Humans, Male, Middle Aged, Universities, Attention physiology, Cross-Cultural Comparison, Ethnicity psychology, Hepatitis C physiopathology, Neuropsychological Tests statistics & numerical data, Psychomotor Performance physiology
- Abstract
Neuropsychologists routinely assess patients from racially, ethnically, and culturally diverse populations. Despite this fact, there remains a paucity of research investigating the influence of these variables on neuropsychological test performance. The Symbol Digit Modalities Test (SDMT) is a widely used measure of attention, visual scanning and tracking, and psychomotor speed. The purpose of the present study was to assess the relation between ethnicity and SDMT performance in ethnically diverse cognitively normal and cognitively impaired samples. Participants were 168 college students (81 Caucasian, 49 African American, 20 Asian American, and 18 Hispanic) and 24 patients (12 Caucasian and 12 Hispanic) chronically infected with hepatitis C. Results revealed no significant group differences in SDMT performance in either the student or patient sample. Furthermore ethnicity accounted for only 2 and 3 percent of the variance in SDMT scores for the patient and student samples, respectively. These findings provide preliminary support for the use of the SDMT across ethnically diverse populations in both clinical and normal samples though further analysis is warranted.
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- 2007
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15. Automated assay for HER-2/neu in serum.
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Payne RC, Allard JW, Anderson-Mauser L, Humphreys JD, Tenney DY, and Morris DL
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- Antibodies, Monoclonal blood, Antibodies, Monoclonal, Humanized, Antineoplastic Agents blood, Breast Neoplasms blood, Female, Humans, Immunoassay, Sensitivity and Specificity, Trastuzumab, Biomarkers, Tumor blood, Receptor, ErbB-2 blood
- Abstract
Background: The extracellular domain of the HER-2/neu oncogene product is increased in sera of some patients with epithelial cancers. Our aim was to develop an automated serum assay for the extracellular domain of the HER-2/neu protein., Methods: We used a monoclonal antibody labeled with fluorescein for capture and a monoclonal Fab' fragment labeled with alkaline phosphatase for detection. Separation of bound and free detection conjugate was performed with magnetizable particles coated with monoclonal antibody to fluorescein. Alkaline phosphatase activity was measured kinetically at 405 or 450 nm., Results: The assay was linear from 0.1 to 250 microg/L. No hook effect was evident up to 10 000 microg/L. Within-run imprecision (CV) was 0.8-1.2%, and total imprecision was 1.1-1.7%. Cross-reactivity with human epidermal growth factor receptor, which has extensive homology with HER-2/neu extracellular domain, was <0.6%. Human anti-mouse antibodies, heterophilic antibodies, and rheumatoid factor did not interfere, nor did the therapeutic monoclonal antibody Herceptin((R)). In 51 healthy females, the mean value was 9.3 microg/L with a range of 6.4-14.0 microg/L. No reagent lot-to-lot variability was detected over four lots of reagents tested., Conclusion: The Bayer Immuno 1(TM) assay for HER-2/neu was precise and resistant to interferences, characteristics that are essential for longitudinal monitoring of cancer patients.
- Published
- 2000
16. Unruptured sinus of valsalva aneurysm and bicuspid aortic valve with aortic cusp perforation: detection by color flow Doppler mapping.
- Author
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Humphreys JD, Ballerio FO, and Davolos DG
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- Aortic Valve pathology, Calcinosis pathology, Echocardiography, Heart Valve Diseases diagnostic imaging, Heart Valve Diseases pathology, Humans, Male, Middle Aged, Aortic Aneurysm complications, Aortic Aneurysm diagnostic imaging, Aortic Valve abnormalities, Aortic Valve diagnostic imaging, Sinus of Valsalva
- Abstract
Congestive heart failure developed in a 53-year-old man with a history of bicuspid aortic valve, angina, and pericarditis. Two-dimensional echocardiography showed a sinus of Valsalva aneurysm related to the anterior coronary sinus and color flow mapping identified a perforation of the anterior aortic cusp. These findings were confirmed during surgery.
- Published
- 1992
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17. Synthesis of a soluble catalase-dextran conjugate.
- Author
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Marshall JJ and Humphreys JD
- Subjects
- Methods, Molecular Weight, Catalase metabolism, Dextrans
- Abstract
Results of a systematic study of the conditions for preparation of soluble catalase-dextran conjugates, using the cyanogen bromide activation procedure, are reported. A protocol for the synthesis of such a conjugate with satisfactory retention of enzymatic activity and high efficiency of coupling is described.
- Published
- 1977
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18. Microbial cells living immobilised on metal hydroxides.
- Author
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Kennedy JF, Barker SA, and Humphreys JD
- Subjects
- Immobilization, Titanium, Zirconium, Escherichia coli, Hydroxides, Saccharomyces cerevisiae
- Published
- 1976
- Full Text
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19. Attachment of carbohydrate to enzymes increases their circulatory lifetimes.
- Author
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Marshall JJ, Humphreys JD, and Abramson SL
- Subjects
- Animals, Bacillus enzymology, Bacillus subtilis enzymology, Cattle, Kinetics, Liver enzymology, Mice, Protein Binding, Rats, Amylases blood, Catalase blood, Dextrans blood, alpha-Amylases blood
- Published
- 1977
- Full Text
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20. Circulating levels of pregnancy specific beta 1 glycoprotein in pregnancies complicated by diabetes mellitus.
- Author
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Grudzinskas JG, Gordon YB, Humphreys JD, Brudenell M, and Chard T
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- Female, Humans, Insulin therapeutic use, Pregnancy, Pregnancy Trimester, Third, Pregnancy in Diabetics drug therapy, Pregnancy Proteins blood, Pregnancy in Diabetics blood, Pregnancy-Specific beta 1-Glycoproteins blood
- Abstract
Circulating levels of SP1 were measured in 20 insulin dependent diabetic women during the third trimester of pregnancy. With one exception, SP1 levels were between the 80 per cent confidence limits of the normal range. The exception was a patient who was delivered of a normal infant at 37 weeks but had consistently low levels of SP1 from 32 weeks until delivery, suggesting a specific defect in SP1 synthesis.
- Published
- 1979
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21. Enhanced stability of erythrocyte-entrapped glucocerebrosidase activity.
- Author
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Humphreys JD and Ihler G
- Subjects
- Carrier Proteins metabolism, Chloromercuribenzoates pharmacology, Dithiothreitol pharmacology, Female, Glucose, Half-Life, Humans, NADP pharmacology, Pregnancy, Serum Albumin, Bovine metabolism, Temperature, Erythrocytes enzymology, Glucosidases metabolism, Glucosylceramidase metabolism
- Abstract
The stability of free glucocerebrosidase activity has been compared with the stability of glucocerebrosidase entrapped in hemolyzed, resealed erythrocytes. Encapsulation markedly stabilizes the enzyme, partly by providing an environment with a high protein concentration. In addition, in the presence of glucose, enzyme activity and GSH content remain constant, but in its absence, enzyme activity and GSH levels fall, indicating the existance of an additional, metabolically linked protective mechanism. Since the free enzyme is inactivated by p-CMB and is protected by DTT, it is likely that GSH generated by the pentose phosphate pathway protects essential sulfhydryl groups of glucocerebrosidase.
- Published
- 1980
22. Isolation of synthetic enzyme-dextran conjugates by chromatography on concanavalin A-sepharose.
- Author
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Marshall JJ and Humphreys JD
- Subjects
- Chromatography, Gel methods, Dextrans isolation & purification, Methods, Receptors, Concanavalin A, Catalase isolation & purification, Concanavalin A, Enzymes, Immobilized isolation & purification
- Published
- 1977
- Full Text
- View/download PDF
23. Insoluble complexes of amino-acids, peptides, and enzymes with metal hydroxides.
- Author
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Kennedy JF, Barker SA, and Humphreys JD
- Subjects
- Peptides, Cyclic, Solubility, Amino Acids, Enzymes, Hydroxides, Metals, Peptides
- Published
- 1976
- Full Text
- View/download PDF
24. Active immobilized antibiotics based on metal hydroxides.
- Author
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Kennedy JF and Humphreys JD
- Subjects
- Bacteria drug effects, Bacteria growth & development, Chemical Phenomena, Chemistry, Chlorides, Hydroxides chemical synthesis, Anti-Bacterial Agents pharmacology, Hydroxides pharmacology, Metals
- Abstract
The water-insoluble hydroxides of zirconium (IV), titanium (IV), titanium (III), iron (II), vanadium (III), and tin (II) have been used to prepare insoluble derivatives of a cyclic peptide antibiotic by a facile chelation process. Testing of the antibacterial activities of the products against two gram-positive and two gram-negative bacteria showed that in the majority of cases the water-insoluble antibiotics remained active against those bacteria susceptible to the parent antibiotic. The power of the assay system has been extended by the novel use of colored organisms to aid determinations where the growth of normal organisms could not be distinguished from the appearance of the supporting material. Insoluble derivatives of neomycin, polymyxin B, streptomycin, ampicillin, penicillin G, and chloramphenicol were prepared by chelation with zirconium hydroxide, and these derivatives similarly reflected the antibacterial activities of the parent compounds. Several of the metal hydroxides themselves possess antibacterial activity due to complex formation with the bacteria. However, the use of selected metal hydroxides can afford a simple, inexpensive, and inert matrix for antibiotic immobilization, resulting in an antibacterial product that may possess slow-release properties. The mechanisms by which the metal hydroxide-antibiotic association-dissociation may occur are discussed.
- Published
- 1976
- Full Text
- View/download PDF
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