701
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Chow T, Yan S, Brown A. Nasal vault/tip/base rhinoplastic reconstruction: A seven-year retrospective review. Int J Oral Maxillofac Surg 1999. [DOI: 10.1016/s0901-5027(99)80788-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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702
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Borsani G, DeGrandi A, Ballabio A, Bulfone A, Bernard L, Banfi S, Gattuso C, Mariani M, Dixon M, Donnai D, Metcalfe K, Winter R, Robertson M, Axton R, Brown A, van Heyningen V, Hanson I. EYA4, a novel vertebrate gene related to Drosophila eyes absent. Hum Mol Genet 1999; 8:11-23. [PMID: 9887327 DOI: 10.1093/hmg/8.1.11] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have isolated a family of four vertebrate genes homologous to eyes absent (eya), a key regulator of ocular development in Drosophila. Here we present the detailed characterization of the EYA4 gene in human and mouse. EYA4 encodes a 640 amino acid protein containing a highly conserved C-terminal domain of 271 amino acids which in Drosophila eya is known to mediate developmentally important protein-protein interactions. Human EYA4 maps to 6q23 and mouse Eya4 maps to the predicted homology region near the centromere of chromosome 10. In the developing mouse embryo, Eya4 is expressed primarily in the craniofacial mesenchyme, the dermamyotome and the limb. On the basis of map position and expression pattern, EYA4 is a candidate for oculo-dento-digital (ODD) syndrome, but no EYA4 mutations were found in a panel of ODD patients.
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703
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Chambers L, Brown A, Pritchard DI, Sreedharan S, Brocklehurst K, Kalsheker NA. Enzymatically active papain preferentially induces an allergic response in mice. Biochem Biophys Res Commun 1998; 253:837-40. [PMID: 9918815 DOI: 10.1006/bbrc.1998.9862] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human exposure to papain, a cysteine proteinase, is associated with hypersensitivity reactions. We demonstrate in mice that enzymatically active papain preferentially induces an IgG1 response and results in mast cell degranulation, both features typical of an allergic reaction. Inactive papain, blocked with E-64, appears to desensitize mice to subsequent challenge by active enzyme. These results suggest that the enzymatic activity of papain is critical in inducing an allergic response and that the use of inactive allergens may be a possible strategy for desensitizing allergic individuals.
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704
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Rosenstock J, Brown A, Fischer J, Jain A, Littlejohn T, Nadeau D, Sussman A, Taylor T, Krol A, Magner J. Efficacy and safety of acarbose in metformin-treated patients with type 2 diabetes. Diabetes Care 1998; 21:2050-5. [PMID: 9839093 DOI: 10.2337/diacare.21.12.2050] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To demonstrate the efficacy, tolerability, and safety of acarbose compared with placebo in patients with type 2 diabetes inadequately controlled with diet and metformin (2,000 or 2,500 mg/day in divided doses). RESEARCH DESIGN AND METHODS This study had a multicenter randomized double-blind placebo-controlled parallel-group comparison design. The trial lasted 31 weeks and consisted of a 1-week screening period, a 6-week placebo pretreatment period, and a 24-week period of acarbose or placebo, with a forced titration from 25-50 mg t.i.d. and a titration of 50-100 mg tid that was based on glucose control. The primary efficacy variable was the mean change from baseline in HbA1c. Secondary efficacy variables included mean changes from baseline in fasting and postprandial plasma glucose, serum insulin, and triglyceride levels. RESULTS The addition of acarbose to patients on background metformin and diet therapy showed a statistically significant reduction in mean HbA1c of 0.65%. There were statistically significant reductions in fasting and postprandial plasma glucose and serum insulin levels compared with placebo. Gastrointestinal side effects were more frequently reported in the acarbose-treated patients. No significant differences in liver transaminase elevations were observed between patients treated with acarbose and those treated with placebo. CONCLUSIONS The results of this study demonstrate that the addition of acarbose to patients with type 2 diabetes who are inadequately controlled with metformin and diet is safe and generally well tolerated and that it significantly lowers HbA1c and fasting and postprandial glucose and insulin levels.
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705
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706
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Brown A, Wyatt M, Eddeb F, Mantle D. Plasma lipid peroxidation during vascular surgery. Biochem Soc Trans 1998; 26:S334. [PMID: 10047848 DOI: 10.1042/bst026s334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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707
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Cotton JM, Brown A, Monaghan MJ. Images in cardiology. Dual atrial pathology as an incidental finding on thoracic computed tomography and echocardiography. Heart 1998; 80:508. [PMID: 9930054 PMCID: PMC1728847 DOI: 10.1136/hrt.80.5.508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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708
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Eddeb F, Brown A, Pickering A, Mendelow D, Mantle D. Effect of antioxidant plant extracts on oxidative protein damage in brain tissue. Biochem Soc Trans 1998; 26:S333. [PMID: 10047847 DOI: 10.1042/bst026s333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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709
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Caplan GA, Brown A, Croker WD, Doolan J. Risk of admission within 4 weeks of discharge of elderly patients from the emergency department--the DEED study. Discharge of elderly from emergency department. Age Ageing 1998; 27:697-702. [PMID: 10408663 DOI: 10.1093/ageing/27.6.697] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE to identify risk factors for admission for patients aged 75 years and older after discharge from the emergency department (DEED: discharge of elderly from emergency department). DESIGN Prospective evaluation of discharged elderly patients from the emergency department who were followed up after 4 weeks. SETTING emergency department of a teaching hospital for 1 year. SUBJECTS patients aged 75 and over discharged to their home or hostel. MAIN OUTCOME MEASURES demographic data, indices of function and cognitive status and admission to hospital within 4 weeks. RESULTS 468 patients aged 75 and over (mean age 81.7 years; range 75-98) were enrolled; 80 patients (17.1%) were admitted to hospital during the subsequent 4 weeks. Risk factors for admission included dependence in the following activities of daily living (relative risk; 95% confidence interval): bathing (2.41; 1.32-4.41); dressing (2.38; 1.22-4.63); stairs (1.60; 1.09-2.33); finance (1.66; 1.23-2.25); shopping (1.39; 1.12-1.73) and transport (1.61; 1.25-2.06), as well as use of a community nurse (1.88; 1.12-3.17). Logistic regression analysis found two variables to be significant in predicting admission or not: dependence in transport and use of a community nurse. CONCLUSIONS older patients are at increased risk of readmission within 4 weeks of being sent home from the emergency department. It is possible to identify high-risk patients by a questionnaire. This allows targeting of these patients for more intensive follow-up in an attempt to ameliorate further deteriorations in their health.
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710
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Piggott MA, Perry EK, Marshall EF, McKeith IG, Johnson M, Melrose HL, Court JA, Lloyd S, Fairbairn A, Brown A, Thompson P, Perry RH. Nigrostriatal dopaminergic activities in dementia with Lewy bodies in relation to neuroleptic sensitivity: comparisons with Parkinson's disease. Biol Psychiatry 1998; 44:765-74. [PMID: 9798081 DOI: 10.1016/s0006-3223(98)00127-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND In dementia with Lewy bodies (DLB) mild extrapyramidal symptoms are associated with moderate reductions in substantia nigra neuron density and concentration of striatal dopamine. Many DLB patients treated with typical neuroleptics suffer severe adverse reactions, which result in decreased survival. METHODS In a series of DLB cases, with and without neuroleptic sensitivity, substantia nigra neuron densities, striatal dopamine and homovanillic acid concentrations, and autoradiographic [3H]mazindol and [3H]raclopride binding (to the dopamine transporter and D2 receptor, respectively) were analyzed and compared to control and idiopathic Parkinson's disease cases. RESULTS D2 receptors were up-regulated in neuroleptictolerant DLB and Parkinson's disease compared to DLB without neuroleptic exposure and controls. D2 receptors were not up-regulated in DLB cases with severe neuroleptic reactions. Dopamine uptake sites were reduced concomitantly with substantia nigra neuron density in Parkinson's disease compared to controls, but there was no significant correlation between substantia nigra neuron density and [3H]mazindol binding in DLB groups. There was no significant difference in substantia nigra neuron density, [3H]mazindol binding, and dopamine or homovanillic acid concentration between neuroleptic-tolerant and -sensitive groups. CONCLUSIONS Failure to up-regulate D2 receptors in response to neuroleptic blockade or reduced dopaminergic innervation may be the critical factor responsible for neuroleptic sensitivity.
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711
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Rodman JS, Lipman R, Brown A, Bronson RT, Dice JF. Rate of accumulation of Luxol Fast Blue staining material and mitochondrial ATP synthase subunit 9 in motor neuron degeneration mice. Neurochem Res 1998; 23:1291-6. [PMID: 9804285 DOI: 10.1023/a:1020748317608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The rate of accumulation of Luxol Fast Blue staining material in the hippocampus of motor neuron degeneration (mnd/mnd) mice, a model of Batten Disease, was quantitated. Stained material increased linearly up to 8 months of age. A quantitative immunoassay was used to measure levels of mitochondrial ATP synthase subunit 9 in brain and liver of mnd/mnd mice. Levels of subunit 9 increased progressively throughout the lifespan of mnd/mnd mice reaching levels approximately 5-fold higher than in control animals. The rate of accumulation of subunit 9 is not consistent with any simple complete or partial degradation defect that is constant throughout the animal's life. Two more complicated models are discussed which are consistent with the observed accumulation rate of subunit 9.
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712
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Brown A. DNA as an investigative technique. Sci Justice 1998. [DOI: 10.1016/s1355-0306(98)73036-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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713
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Caplan GA, Brown A, Crowe PJ, Yap SJ, Noble S. Re-engineering the elective surgical service of a tertiary hospital: a historical controlled trial. Med J Aust 1998; 169:247-51. [PMID: 9762061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE To study the clinical effects of re-engineering the processes associated with elective surgery. DESIGN A prospective, historical controlled trial. Control patients were enrolled from March 1995 to January 1996, and postintervention patients from February 1996 to October 1996. SETTING A major teaching, tertiary care hospital (Prince of Wales Hospital, Sydney). PATIENTS 224 patients (123 before and 101 after the intervention) undergoing elective herniorrhaphy of laparoscopic cholecystectomy who lived in the local area. INTERVENTION Introduction of a re-engineered surgical service consisting of preadmission assessment and education, admission on day of surgery, and postacute care after discharge. There were no changes to the operative methods or infection control procedures. MAIN OUTCOME MEASURES Length of stay, operative complications, pain scores and patient satisfaction. RESULTS The risk of a patient suffering one or more complications was reduced in the postintervention group (postintervention v. control patients: 25.7% v. 38.2%; relative risk [RR], 0.66; 95% confidence interval [CI], 0.44-0.98; P = 0.035) because of a reduced risk of wound infections (5.0% v. 16.3%; RR, 0.30; 95% CI, 0.12-0.78; P = 0.0075). Other complications (perioperative or postoperative) and pain scores were unchanged. Patients treated by the re-engineered service had a significantly shorter length of stay, reported a higher level of satisfaction with the preoperative and postdischarge care, and were more likely to say that they would have the same treatment again (92.9% v 82.6%; P = 0.037). CONCLUSIONS Re-engineering surgical services, with an associated reduction in length of stay, does not lead to a deterioration in care and may decrease postoperative complications and increase patient satisfaction.
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714
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Teshima DY, Brown A, Gon S, Nelson L, Gushikuma S. Surfing the wave of clinical laboratory science evolution in Hawai'i. CLINICAL LABORATORY SCIENCE : JOURNAL OF THE AMERICAN SOCIETY FOR MEDICAL TECHNOLOGY 1998; 11:269-72. [PMID: 10186950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
OBJECTIVE To describe the steps taken by the Hawaii Society for Clinical Laboratory Science, an affiliate of the American Society for Clinical Laboratory Science, to inform local laboratory professionals of current trends and to prepare for the future. RESULTS A Strategic Planning workshop was conducted at the 1997 Hawaii Society for Clinical Laboratory Science Annual Meeting where participants reviewed the essential (but non-traditional) functions of clinical laboratory scientists, and described current realities, identified forces and players affecting the changes, and envisioned the future of our profession. CONCLUSION As the way health care is provided changes in response to economics and advances in technology, the role of clinical laboratory scientists needs to be redefined. The Hawaii Society for Clinical Laboratory Science continues to provide timely support for members, and plans to work collaboratively with the local chapter of the Clinical Laboratory Managers' Association to advance clinical laboratory science to an appropriate place in the health care community.
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715
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Cullinane M, Wainwright R, Brown A, Monaghan M, Markus HS. Asymptomatic embolization in subjects with atrial fibrillation not taking anticoagulants: a prospective study. Stroke 1998; 29:1810-5. [PMID: 9731600 DOI: 10.1161/01.str.29.9.1810] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Embolism is believed to be the major cause of stroke in patients with nonvalvular atrial fibrillation (NVAF). The detection of asymptomatic embolic signals (ES) in individuals with NVAF might allow identification of patients at high risk of stroke and monitoring of therapy in individual subjects. We determined the frequency of asymptomatic ES in patients with NVAF who were not taking warfarin. METHODS Bilateral transcranial Doppler recordings were made for 1 hour from the middle cerebral arteries of 111 successive patients with NVAF taking aspirin alone or no antithrombotic or anticoagulant therapy. Adequate recordings could be made in 86 patients. In 79 subjects, recordings were performed on a second occasion to study temporal variability. Recordings for a single hour were also made in 30 age-matched control subjects. RESULTS ES were detected in 13 (15.1%) of NVAF subjects but in no control subjects (P=0.02). ES were detected both in subjects with symptomatic NVAF (4 of 30 [13.1%], P=0.04 versus controls) and asymptomatic NVAF (9 of 56 [16.1%], P=0.02 versus controls). There was no correlation between the presence of ES and smoking status, diabetes, hypertension, aspirin use, aspirin dose, symptomatic status, left atrial size, left ventricular function, or the presence of left atrial thrombus detected on transthoracic echocardiography. Repeating the recording increased the number of patients with ES to 21 (26.6%). On considering the results of both recordings, again there was no association for either recording between the presence of ES and smoking status, diabetes, hypertension, aspirin use, aspirin dose, age, symptomatic status, left atrial size, or left ventricular function. On repeating the recording, in the symptomatic group only 2 patients (8%) changed status, in contrast to 15 (29%) in the asymptomatic group. CONCLUSIONS ES can be detected in patients with NVAF at a low frequency. Particularly in asymptomatic patients, ES show marked temporal variability. We found no correlation between the presence of previously reported clinical and echocardiographic markers of increased stroke risk and the presence of ES. This association requires further investigation before the clinical utility of this technique in patients with NVAF is decided.
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716
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Fisher B, Bryant J, Wolmark N, Mamounas E, Brown A, Fisher ER, Wickerham DL, Begovic M, DeCillis A, Robidoux A, Margolese RG, Cruz AB, Hoehn JL, Lees AW, Dimitrov NV, Bear HD. Effect of preoperative chemotherapy on the outcome of women with operable breast cancer. J Clin Oncol 1998; 16:2672-85. [PMID: 9704717 DOI: 10.1200/jco.1998.16.8.2672] [Citation(s) in RCA: 1546] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
PURPOSE To determine, in women with primary operable breast cancer, if preoperative doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan; AC) therapy yields a better outcome than postoperative AC therapy, if a relationship exists between outcome and tumor response to preoperative chemotherapy, and if such therapy results in the performance of more lumpectomies. PATIENTS AND METHODS Women (1,523) enrolled onto National Surgical Adjuvant Breast and Bowel Project (NSABP) B-18 were randomly assigned to preoperative or postoperative AC therapy. Clinical tumor response to preoperative therapy was graded as complete (cCR), partial (cPR), or no response (cNR). Tumors with a cCR were further categorized as either pathologic complete response (pCR) or invasive cells (pINV). Disease-free survival (DFS), distant disease-free survival (DDFS), and survival were estimated through 5 years and compared between treatment groups. In the preoperative arm, proportional-hazards models were used to investigate the relationship between outcome and tumor response. RESULTS There was no significant difference in DFS, DDFS, or survival (P = .99, .70, and .83, respectively) among patients in either group. More patients treated preoperatively than postoperatively underwent lumpectomy and radiation therapy (67.8% v 59.8%, respectively). Rates of ipsilateral breast tumor recurrence (IBTR) after lumpectomy were similar in both groups (7.9% and 5.8%, respectively; P = .23). Outcome was better in women whose tumors showed a pCR than in those with a pINV, cPR, or cNR (relapse-free survival [RFS] rates, 85.7%, 76.9%, 68.1%, and 63.9%, respectively; P < .0001), even when baseline prognostic variables were controlled. When prognostic models were compared for each treatment group, the preoperative model, which included breast tumor response as a variable, discriminated outcome among patients to about the same degree as the postoperative model. CONCLUSION Preoperative chemotherapy is as effective as postoperative chemotherapy, permits more lumpectomies, is appropriate for the treatment of certain patients with stages I and II disease, and can be used to study breast cancer biology. Tumor response to preoperative chemotherapy correlates with outcome and could be a surrogate for evaluating the effect of chemotherapy on micrometastases; however, knowledge of such a response provided little prognostic information beyond that which resulted from postoperative therapy.
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717
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DeLorenzo RJ, Waterhouse EJ, Towne AR, Boggs JG, Ko D, DeLorenzo GA, Brown A, Garnett L. Persistent nonconvulsive status epilepticus after the control of convulsive status epilepticus. Epilepsia 1998; 39:833-40. [PMID: 9701373 DOI: 10.1111/j.1528-1157.1998.tb01177.x] [Citation(s) in RCA: 364] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE Convulsive status epilepticus (CSE) is a major medical and neurological emergency that is associated with significant morbidity and mortality. Despite this high morbidity and mortality, most acute care facilities in the United States cannot evaluate patients with EEG monitoring during or immediately after SE. The present study was initiated to determine whether control of CSE by standard treatment protocols was sufficient to terminate electrographic seizures. METHODS One hundred sixty-four prospective patients were evaluated at the Medical College of Virginia/VCU Status Epilepticus Program. Continuous EEG monitoring was performed for a minimum of 24 h after clinical control of CSE. SE and seizure types were defined as described previously. A standardized data form entry system was compiled for each patient and used to evaluate the data collected. RESULTS After CSE was controlled, continuous EEG monitoring demonstrated that 52% of the patients had no after-SE ictal discharges (ASIDS) and manifested EEG patterns of generalized slowing, attenuation, periodic lateralizing epileptiform discharges (PLEDS), focal slowing, and/or burst suppression. The remaining 48% demonstrated persistent electrographic seizures. More than 14% of the patients manifested nonconvulsive SE (NCSE) predominantly of the complex partial NCSE seizure (CPS) type (2). These patients were comatose and showed no overt clinical signs of convulsive activity. Clinical detection of NCSE in these patients would not have been possible with routine neurological evaluations without use of EEG monitoring. The clinical presentation, mortality, morbidity, and demographic information on this population are reported. CONCLUSIONS Our results demonstrate that EEG monitoring after treatment of CSE is essential to recognition of persistent electrographic seizures and NCSE unresponsive to routine therapeutic management of CSE. These findings also suggest that EEG monitoring immediately after control of CSE is an important diagnostic test to guide treatment plans and to evaluate prognosis in the management of SE.
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718
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Brown A. Influence of concomitant disease on patterns of hospitalization in patients with heart failure discharged from Scottish hospitals in 1995. Eur Heart J 1998. [DOI: 10.1053/euhj.1997.0859] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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719
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Noble M, Brown A, Jauregi P, Kaul A, Varley J. Protein recovery using gas-liquid dispersions. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 711:31-43. [PMID: 9699972 DOI: 10.1016/s0378-4347(98)00030-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Two separation techniques, foam separation and colloidal gas aphrons (CGAs), both of which are based on gas-liquid dispersions, are compared as potential applications for protein recovery in downstream processing. The potential advantages of each method are described and the concentration and selectivity achieved with each method, for a range of proteins is discussed. The physical basis of foam separation is the preferential adsorption of surface active species at a gas-liquid interface, with surface inactive species remaining in bulk solution. When a solution containing surface active species is sparged with gas, a foam is produced at the surface: this foam can be collected, and upon collapse contains surface active species in a concentrated form. CGAs are microbubble dispersions (bubble diameters 10-100 microm) with high gas hold ups (>50%) and relatively high stability, which are formed by stirring a surfactant solution at speeds above a critical value (typically around 5000 rpm). It is expected that when proteins are brought into contact with aphrons, protein adsorbs to the surfactant through electrostatic and/or hydrophobic forces. The aphron phase can be separated easily from the bulk solution due to its buoyancy, thus allowing separation of protein in a concentrated form.
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720
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Brown A, Jolly P, Wei H. Genistein modulates neuroblastoma cell proliferation and differentiation through induction of apoptosis and regulation of tyrosine kinase activity and N-myc expression. Carcinogenesis 1998; 19:991-7. [PMID: 9667736 DOI: 10.1093/carcin/19.6.991] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Genistein is a specific inhibitor of protein tyrosine kinase (PTK) and is considered as a therapeutic candidate for various cancers. In this paper we investigate the effects of genistein on cell proliferation and differentiation in neuroblastoma (NB) cell lines and its possible mechanism of action. Genistein substantially inhibited the growth of five (N2A, JC, SKNSH, MSN and Lan5) of the six tumor cell lines examined in a dose-dependent manner with an IC50 value of approximately 5 microg/ml. The exception was GC cells. N2A cells were treated with genistein for 6 days and exhibited morphological features of differentiation, as evidenced by the development of dendritic extensions. Terminal deoxynucleotidyl transferase (TDT) histochemical staining showed a significant elevation in darkly stained nuclei in genistein-treated N2A cells compared with controls, indicating the occurrence of apoptosis. Fluorescent quantitation of DNA fragments confirmed apoptosis in genistein-treated N2A cells. To further elucidate the possible mechanisms by which genistein modulates NB cell growth and differentiation we investigated the effect of genistein on the activities of PTK and mitogen-activated protein (MAP) kinase and N-myc proto-oncogene expression in N2A cells. The results showed that genistein down-regulated intrinsic PTK activity by approximately 33% and inhibited insulin-like growth factor (IGF)-stimulated PTK activity by 75%. The effect of genistein on the intrinsic activity of MAP kinase was insignificant. In addition, genistein significantly reduced N-myc expression in a dose-dependent fashion. Our study suggests that genistein arrests cell growth and induces NB cell differentiation by mediating apoptosis and modulating PTK activity and N-myc proto-oncogene expression.
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721
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Johnstone F, Goldberg D, Tappin D, Mathie L, Cameron S, Brown A, Burns S, Hamilton B, Codere G, Girdwood RW. The incidence and prevalence of HIV infection among childbearing women living in Edinburgh city, 1982-1995. AIDS 1998; 12:911-8. [PMID: 9631145 DOI: 10.1097/00002030-199808000-00014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To track the complete course of the HIV epidemic among women from the city of Edinburgh who delivered babies during 1982-1995. METHODS The performance of the modified Serodia HIV test on dried blood spots from archived neonatal metabolic screening cards stored for up to 11 years was evaluated by testing 221 cards from neonates whose mothers' HIV infection status was already known (100 HIV-positive, 121 HIV-negative). Unlinked anonymous HIV testing of cards from neonates born during 1982-1989 was then performed and the resulting prevalence data were combined with existing data from 1990-1995. Maximum and minimum limits of HIV incidence among women during the 36-month period prior to delivery were calculated using data held on a clinical database of HIV-infected pregnant women that had been generated under strict conditions of confidentiality; these data included the date of the woman's first HIV-positive and, if available, last HIV-negative specimen. RESULTS The evaluation revealed a sensitivity of 91%, not clearly related to storage time, and a specificity of 100%. HIV infection first entered Edinburgh's childbearing population during the early 1980s with prevalence peaking at 0.4% in 1986 and then decreasing to 0.1% in 1995; a similar incidence profile was seen during this period. Since 1986, the first full year that HIV testing was available, 78% of all infections were known during the pregnancy, 13% were identified retrospectively, and only 10% (10 cases) remain unaccounted for. For infected cases during 1984-1987, 78% were injecting drug users (IDU) and only 22% acquired their infection sexually; this distribution had reversed by 1992-1995. CONCLUSION HIV testing of neonatal metabolic screening cards stored for up to 11 years can yield results of sufficient accuracy for epidemiological purposes. There has been a substantial decline in the prevalence and incidence of HIV since the mid-1980s. Although new infections are still occurring, the numbers are small. The decline may largely be explained by the impact of preventive measures on the spread of HIV amongst IDU, and thus from IDU to their sexual partners.
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722
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Brown A, Dugdill S, Wyatt M, Mantle D. Serum total antioxidant status during vascular surgery. Biochem Soc Trans 1998; 26:S127. [PMID: 9649802 DOI: 10.1042/bst026s127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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723
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Brown A, Dugdill S, Wyatt M, Cooper P, Mantle D. Free radical analysis via ESR spectroscopy during vascular surgery. Biochem Soc Trans 1998; 26:S140. [PMID: 9649815 DOI: 10.1042/bst026s140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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724
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Brown A. Ontogeny of hemocyanin function in the dungeness crab cancer magister: hemolymph modulation of hemocyanin oxygen-binding. J Exp Biol 1998; 201 (Pt 6):819-26. [PMID: 9464962 DOI: 10.1242/jeb.201.6.819] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The in vivo oxygen-binding characteristics of Cancer magister whole hemolymph were compared across developmental stages with those of purified hemocyanin. When the 25S hemocyanins from first-instar juvenile and adult C. magister were dialyzed against first-instar juvenile saline, the P50 values at pH 7.8 differed by 54 %: 2.16 kPa for the adult and 4.68 kPa for the first-instar juvenile. Since both purified proteins were examined under identical conditions, this represents an intrinsic stage-specific difference in hemocyanin O2-affinity. When the two types of hemocyanin were dialyzed against their respective stage-specific salines, the oxygen affinities differed by only 28 %: 3.39 kPa for the adult and still 4.68 kPa for the first-instar juvenile. Thus, the intrinsic difference in hemocyanin O2-affinity was reduced by the stage-specific differences in hemolymph ion concentrations. Even more significant is the fact that the whole-hemolymph P50 values of the juvenile and adult were indistinguishable at in vivo pH and divalent cation levels specific for each stage. Thus, despite significant differences in the intrinsic oxygen affinity of the purified 25S hemocyanin during development, the whole-hemolymph oxygen-binding properties are conserved. In the juvenile crab, it appears that the low-affinity hemocyanin serves to modulate the effects of a weak renal regulation of [Mg2+]. As ion regulation is enhanced during development and divalent cation levels decrease, the crab synthesizes higher-affinity hemocyanin.
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Mehta RJ, Diefenbach B, Brown A, Cullen E, Jonczyk A, Güssow D, Luckenbach GA, Goodman SL. Transmembrane-truncated alphavbeta3 integrin retains high affinity for ligand binding: evidence for an 'inside-out' suppressor? Biochem J 1998; 330 ( Pt 2):861-9. [PMID: 9480902 PMCID: PMC1219217 DOI: 10.1042/bj3300861] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The molecular mechanisms of alphavbeta3 integrin affinity regulation have important biological implications in tumour development, wound repair and angiogenesis. We expressed, purified and characterized recombinant forms of human alphavbeta3 (r-alphavbeta3) and compared the activation state of these with alphavbeta3 in its cellular environment. The ligand specificity and selectivity of recombinant full-length and double transmembrane truncations of r-alphavbeta3 cloned in BacPAK6 vectors and expressed in Sf9 and High Five insect cells were compared with those of native placental alphavbeta3 and the receptor in situ on the cell surface. r-alphavbeta3 integrins were purified by affinity chromatography from detergent extracts of cells (full-length), and from the culture medium of cells expressing double-truncated r-alphavbeta3. r-alphavbeta3 had the same epitopes, ligand-binding specificities, bivalent cation requirements and susceptibility to RGD-containing peptides as native alphavbeta3. On M21-L4 melanoma cells, alphavbeta3 mediated binding to vitronectin, but not to fibrinogen unless activated with Mn2+. Non-activated alphaIIbbeta3 integrin as control in M21-L-IIb cells had the opposite profile, mediating binding to fibrinogen, but not to vitronectin unless activated with Mn2+. Thus these receptors had moderate to low ligand affinity. In marked contrast, purified alphavbeta3 receptors, with or without transmembrane and cytoplasmic domains, were constitutively of high affinity and able to bind strongly to vitronectin, fibronectin and fibrinogen under physiological conditions. Our data suggest that, in contrast with the positive regulation of alphaIIbbeta3 in situ, intracellular controls lower the affinity of alphavbeta3, and the cytoplasmic domains may act as a target for negative regulators of alphavbeta3 activity.
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