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Grelewicz Z, Suzuki K, Kohlbrenner R, Obajuluwa A, Ng E, Tompkins R, Epstein M, Hori M, Baron R. SU-FF-I-03: Computer-Aided Diagnostic Scheme for Detection of Hepatocellular Carcinoma in Contrast-Enhanced Hepatic CT: Preliminary Results. Med Phys 2009. [DOI: 10.1118/1.3181122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Zosmer A, Epstein M, Al-Shawaf T. Ethical recruitment of patients for PGS trial. Hum Reprod 2008; 23:1472; author reply 1472-3. [DOI: 10.1093/humrep/den116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
The medical admissions unit (MAU) of the Royal Free Hospital, London, should receive all acute accident and emergency (A&E) medical admissions. The unit aims to discharge 60% of patients and to transfer the remainder to a base ward within 48 hours of admission. This study tracked the patient journey from admission to A&E through the MAU during two parallel weeks, one year apart. Key bottlenecks were identified in the first audit and reforms implemented prior to the second. These reforms included improved transfer to base wards, improved weekend work patterns and improved access to investigation, specialist teams and pharmacy. The reforms served to facilitate the patient journey. A greater proportion of acute medical admissions were managed on the MAU and the number of patients exceeding a 48-hour stay fell from 55% to 10%. Both study periods demonstrated a peak in transfer activity from A&E in the 20 minutes before the four-hour target.
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Stone M, Stock G, Bunin K, Kumar K, Epstein M, Kambhamettu C, Li M, Parthasarathy V, Prince J. Comparison of speech production in upright and supine position. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2007; 122:532-41. [PMID: 17614510 DOI: 10.1121/1.2715659] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Speech is usually produced in an upright sitting or standing posture. Measurements and judgments of speech may be made in conditions requiring a supine position, however. These conditions include MRI recordings, and oral procedures, such as, adjustments to dental appliances, medical and surgical procedures. It is of interest, therefore, to see whether gravity has strong or systematic effects on tongue behavior. In the present study, 13 subjects repeated several words, which contained extreme consonant and vowel tongue positions, during upright and supine condition. Ultrasound imaging provided midsagittal tongue contours, in each condition, for comparison. A neck brace was used to stabilize transducer placement and the palate was used as a physiological reference to register the data sets. Results showed a significant subject effect. In supine position the tongue was more posterior than upright for seven subjects, more anterior for two subjects and varied by phoneme for four subjects. However, there was no significant phoneme effect. The direction of change and the amount of change were not directly related. Most subjects had small upright-supine differences. The largest differences, less than 3 mm on average, were in the posterior tongue.
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Epstein M, Wingate DL. Is the NHS research ethics committees system to be outsourced to a low-cost offshore call centre? Reflections on human research ethics after the Warner Report. JOURNAL OF MEDICAL ETHICS 2007; 33:45-7. [PMID: 17209111 PMCID: PMC2598083 DOI: 10.1136/jme.2005.015479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The recently published Report of the AHAG on the Operation of NHS Research Ethics Committees (the Warner Report) advocates major reforms of the NHS research ethics committees system. The main implications of the proposed changes and their probable effects on the major stakeholders are described.
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Warner JV, Nyholt DR, Busfield F, Epstein M, Burgess J, Stranks S, Hill P, Perry-Keene D, Learoyd D, Robinson B, Teh BT, Prins JB, Cardinal JW. Familial isolated hyperparathyroidism is linked to a 1.7 Mb region on chromosome 2p13.3-14. J Med Genet 2006; 43:e12. [PMID: 16525030 PMCID: PMC2563254 DOI: 10.1136/jmg.2005.035766] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Familial isolated hyperparathyroidism (FIHP) is an autosomal dominantly inherited form of primary hyperparathyroidism. Although comprising only about 1% of cases of primary hyperparathyroidism, identification and functional analysis of a causative gene for FIHP is likely to advance our understanding of parathyroid physiology and pathophysiology. METHODS A genome-wide screen of DNA from seven pedigrees with FIHP was undertaken in order to identify a region of genetic linkage with the disorder. RESULTS Multipoint linkage analysis identified a region of suggestive linkage (LOD score 2.68) on chromosome 2. Fine mapping with the addition of three other families revealed significant linkage adjacent to D2S2368 (maximum multipoint LOD score 3.43). Recombination events defined a 1.7 Mb region of linkage between D2S2368 and D2S358 in nine pedigrees. Sequencing of the two most likely candidate genes in this region, however, did not identify a gene for FIHP. CONCLUSIONS We conclude that a causative gene for FIHP lies within this interval on chromosome 2. This is a major step towards eventual precise identification of a gene for FIHP, likely to be a key component in the genetic regulation of calcium homeostasis.
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Epstein M. Why effective consent presupposes autonomous authorisation: a counterorthodox argument. JOURNAL OF MEDICAL ETHICS 2006; 32:342-5. [PMID: 16731733 PMCID: PMC2563374 DOI: 10.1136/jme.2005.013227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Effective consent is indeed a legal fiction
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Cardinal JW, Bergman L, Hayward N, Sweet A, Warner J, Marks L, Learoyd D, Dwight T, Robinson B, Epstein M, Smith M, Teh BT, Cameron DP, Prins JB. A report of a national mutation testing service for the MEN1 gene: clinical presentations and implications for mutation testing. J Med Genet 2006; 42:69-74. [PMID: 15635078 PMCID: PMC1735899 DOI: 10.1136/jmg.2003.017319] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
INTRODUCTION Mutation testing for the MEN1 gene is a useful method to diagnose and predict individuals who either have or will develop multiple endocrine neoplasia type 1 (MEN 1). Clinical selection criteria to identify patients who should be tested are needed, as mutation analysis is costly and time consuming. This study is a report of an Australian national mutation testing service for the MEN1 gene from referred patients with classical MEN 1 and various MEN 1-like conditions. RESULTS All 55 MEN1 mutation positive patients had a family history of hyperparathyroidism, had hyperparathyroidism with one other MEN1 related tumour, or had hyperparathyroidism with multiglandular hyperplasia at a young age. We found 42 separate mutations and six recurring mutations from unrelated families, and evidence for a founder effect in five families with the same mutation. DISCUSSION Our results indicate that mutations in genes other than MEN1 may cause familial isolated hyperparathyroidism and familial isolated pituitary tumours. CONCLUSIONS We therefore suggest that routine germline MEN1 mutation testing of all cases of "classical" MEN1, familial hyperparathyroidism, and sporadic hyperparathyroidism with one other MEN1 related condition is justified by national testing services. We do not recommend routine sequencing of the promoter region between nucleotides 1234 and 1758 (Genbank accession no. U93237) as we could not detect any sequence variations within this region in any familial or sporadic cases of MEN1 related conditions lacking a MEN1 mutation. We also suggest that testing be considered for patients <30 years old with sporadic hyperparathyroidism and multigland hyperplasia.
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Herzog W, Han SK, Federico S, Epstein M. Reply to letter to the editor by Dr. Robert W. Mann. J Biomech 2005. [DOI: 10.1016/j.jbiomech.2005.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lemos RR, Epstein M, Herzog W, Wyvill B. A framework for structured modeling of skeletal muscle. Comput Methods Biomech Biomed Engin 2005; 7:305-17. [PMID: 15621651 DOI: 10.1080/10255840412331317398] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of this study is to present a detailed continuum mechanics formulation, and the corresponding algorithms, to predict the deformation of skeletal muscle at different structural levels, starting from the muscle fiber level. The model is used to investigate force production and structural changes during isometric and dynamic contractions of the cat medial gastrocnemius. From a comparison with experimental data obtained in our own laboratories, we conclude that the model faithfully predicts all of the observations pertaining to force production, fascicle length and angle of pennation under various test conditions.
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Karagiannidis C, Hense G, Martin C, Epstein M, Rückert B, Mantel PY, Uhlig S, Blaser K, Schmidt-Weber C, Menz G. Die Rolle von TGF-beta1 und Activin A beim Asthma bronchiale. Pneumologie 2005. [DOI: 10.1055/s-2005-864487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Warner J, Epstein M, Sweet A, Singh D, Burgess J, Stranks S, Hill P, Perry-Keene D, Learoyd D, Robinson B, Birdsey P, Mackenzie E, Teh BT, Prins JB, Cardinal J. Genetic testing in familial isolated hyperparathyroidism: unexpected results and their implications. J Med Genet 2004; 41:155-60. [PMID: 14985373 PMCID: PMC1735699 DOI: 10.1136/jmg.2003.016725] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Familial hyperparathyroidism is not uncommon in clinical endocrine practice. It encompasses a spectrum of disorders including multiple endocrine neoplasia types 1 (MEN1) and 2A, hyperparathyroidism-jaw tumour syndrome (HPT-JT), familial hypocalciuric hypercalcaemia (FHH), and familial isolated hyperparathyroidism (FIHP). Distinguishing among the five syndromes is often difficult but has profound implications for the management of patient and family. The availability of specific genetic testing for four of the syndromes has improved diagnostic accuracy and simplified family monitoring in many cases but its current cost and limited accessibility require rationalisation of its use. No gene has yet been associated exclusively with FIHP. FIHP phenotypes have been associated with mutant MEN1 and calcium-sensing receptor (CASR) genotypes and, very recently, with mutation in the newly identified HRPT2 gene. The relative proportions of these are not yet clear. We report results of MEN1, CASR, and HRPT2 genotyping of 22 unrelated subjects with FIHP phenotypes. We found 5 (23%) with MEN1 mutations, four (18%) with CASR mutations, and none with an HRPT2 mutation. All those with mutations had multiglandular hyperparathyroidism. Of the subjects with CASR mutations, none were of the typical FHH phenotype. These findings strongly favour a recommendation for MEN1 and CASR genotyping of patients with multiglandular FIHP, irrespective of urinary calcium excretion. However, it appears that HRPT2 genotyping should be reserved for cases in which other features of the HPT-JT phenotype have occurred in the kindred. Also apparent is the need for further investigation to identify additional genes associated with FIHP.
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Epstein M, Yariv S. Visible-spectroscopy study of the adsorption of alizarinate by Al-montmorillonite in aqueous suspensions and in solid state. J Colloid Interface Sci 2003; 263:377-85. [PMID: 12909026 DOI: 10.1016/s0021-9797(03)00339-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The adsorption of the monovalent anionic dye alizarinate onto Na- and Al-montmorillonite was carried out by adding the dye into aqueous clay suspensions. Electronic spectra of aqueous suspensions and of air-dried dye-clay complexes were studied. Na-montmorillonite adsorbed only part of the added dye. With total amount of alizarinate up to 5 mmol dye per 100 g clay the adsorption of the dye takes place on the broken bonds, leading to peptization of the clay. Al-montmorillonite adsorbed alizarinate completely up to 10 mmol per 100 g clay. Above this loading there was a partition of the dye between the clay and the supernatant. The maximum adsorption for Na- and Al-clay was 4 and 25 mmol dye per 100 g clay, respectively. Absorption bands in the spectrum of Al-montmorillonite suspensions (488-504 nm) appear at longer wavelengths than in the spectrum of air-dried Al-montmorillonite (415-455 nm). Thermo-X-ray study of these clay-alizarinate complexes suggests that the organic compound was located in the interlayer space in Al-montmorillonite but was not located there in Na-montmorillonite. In Al-montmorillonite alizarinate formed a coordination complex with exchangeable Al(3+). In Na-montmorillonite it formed bonds with Al exposed on the broken-bonds sites.
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Epstein M. Evolving therapeutic strategies for retarding progression of diabetic nephropathy--an update for 2002. Acta Diabetol 2002; 39 Suppl 2:S41-5. [PMID: 12222627 DOI: 10.1007/s005920200025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
During the past few years, several major intervention trials have been conducted in an attempt to determine the efficacy of specific antihypertensive agents in retarding progression of diabetic nephropathy. These studies have clearly demonstrated the importance of renin-angiotensin system blockade in attenuating progressive renal disease. The preferred initial therapy is an angiotensin-converting enzyme (ACE) inhibitor, or an angiotensin type I (AT1) receptor antagonist based on the recent 'landmark' proof-of-concept trials--the Irbesartan Type 2 Diabetic Nephropathy Trial (IDNT) and the Reduction of Endpoints in NIDDM with Angiotensin II Antagonist Losartan (RENAAL). However, these clinical trials also demonstrate that aggressive blood pressure targets are needed in patients with diabetes and hypertension. This frequently requires multiple-drug therapy with several different classes of antihypertensive agents. Data from several clinical trials, including RENAAL, suggest that calcium antagonists may be added to ACE inhibitor or AT1 receptor antagonist therapy as needed to achieve target blood pressure. Calcium antagonists could, therefore, constitute an important component of the antihypertensive regimen in the management of patients with diabetic nephropathy.
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Miller R, Epstein M. The use of X-ray fluorescence in rapid in vivo measurements of iodine, gold and mercury. Phys Med Biol 2002. [DOI: 10.1088/0031-9155/19/2/021] [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]
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Sica DA, Struthers AD, Cushman WC, Wood M, Banas JS, Epstein M. Importance of potassium in cardiovascular disease. J Clin Hypertens (Greenwich) 2002; 4:198-206. [PMID: 12045369 PMCID: PMC8101903 DOI: 10.1111/j.1524-6175.2002.01728.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pivotal role of potassium (K+) in cardiovascular disease and the importance of preserving potassium balance have become clinical hot points, particularly as relates to new and emerging cardioprotective and renoprotective therapies that promote potassium retention. Although clinicians may be aware of the critical nature of this relationship, quite frequently there is some uncertainty as to the best way to monitor potassium levels in the face of a host of pathologic states and/or accompanying drug therapies that affect serum levels and/or total body potassium balance. Moreover, guidelines for monitoring of serum potassium levels are at best tentative and oftentimes are translated according to the level of concern of the respective physician. To address these uncertainties, an expert group was convened that included representatives from multiple disciplines. They attempted to reach consensus on the importance of K+ in hypertension, stroke, and arrhythmias as well as practical issues on maintaining K+ balance and avoiding K+ depletion. Because of the complexity of this topic, issues of hyperkalemia will be addressed in a forthcoming manuscript.
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Bakris GL, Smith AC, Richardson DJ, Hung E, Preston R, Goldberg R, Epstein M. Impact of an ACE inhibitor and calcium antagonist on microalbuminuria and lipid subfractions in type 2 diabetes: a randomised, multi-centre pilot study. J Hum Hypertens 2002; 16:185-91. [PMID: 11896508 DOI: 10.1038/sj.jhh.1001315] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2001] [Revised: 08/05/2001] [Accepted: 10/04/2001] [Indexed: 11/09/2022]
Abstract
BACKGROUND Microalbuminuria (MA) is associated with increased cardiovascular risk and lipid abnormalities in people with type 2 diabetes. ACE inhibitors and calcium channel blockers (CCBs) reduce MA and are neutral on total cholesterol and triglycerides. The effect of ACE inhibitors and CCBs on lipid subfractions such as Lp(a), apolipoprotein (apo) A1, apo B, and others, however, is unclear. The current study tests the hypothesis that a fixed-dose combination of an ACE inhibitor, benazepril (B) with the dihydropyridine CCB, amlodipine (A), will further reduce arterial pressure and reduce atherogenic lipid fractions compared to either agent alone. DESIGN A multicentre, randomised, open-label, parallel group design was used to study 27 participants with type 2 diabetes. Measurements for total cholesterol, high- and low-density lipoprotein (HDL and LDL), triglycerides, apo A1, apo B, Lp(a), MA, arterial pressure and creatinine clearance were obtained at baseline and at 12-week intervals during the 36 week study. RESULTS Arterial pressure was significantly reduced at 36 weeks in all three groups (P = 0.0078 for A, P = 0.0039 for B, and P = 0.0313 for A+B). MA was lowered in all groups with relatively greater reductions in the B (P < 0.05) and A+B groups (P < 0.03) vs A. An increase in mean HDL-cholesterol from baseline was noted in the B and A+B groups; P < 0.05), but not in the A group. A trend was also observed between the rise in HDL-cholesterol and the reduction in MA in the B and A+B groups. Additionally, only the B group exhibited a decrease in the median value of Lp(a) (P < 0.05). CONCLUSION These data support the concept that ACE inhibition with B reduces the atherogenic profile by decreasing Lp(a) and increasing HDL-cholesterol, the latter being correlated with reductions in MA. While A+B exhibited similar trends in lipid subfractions and MA as B, this group had the greatest reduction in systolic blood pressure of the three groups. Thus, use of A+B offers the benefits of a decreased atherogenic profile with a higher probably of achieving goal blood pressure as recommended by national guidelines.
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Komers R, Anderson S, Epstein M. Renal and cardiovascular effects of selective cyclooxygenase-2 inhibitors. Am J Kidney Dis 2001; 38:1145-57. [PMID: 11728945 DOI: 10.1053/ajkd.2001.29203] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Selective inhibition of cyclooxygenase-2 (COX-2) was proposed as a novel anti-inflammatory and analgesic treatment with a reduced profile of gastrointestinal side effects compared with conventional nonsteroidal anti-inflammatory drugs (NSAIDs). Although perceived as an inducible enzyme by inflammatory and other stimuli, COX-2 is constitutively expressed in the kidney. In this review, we focus on renal and cardiovascular (CV) physiological and pathophysiological characteristics of COX-2 and renal and CV aspects of treatment with selective COX-2 inhibitors. Both clinical and experimental studies have shown that renal and CV effects of COX-2 inhibitors are similar to those of NSAIDs. These effects include sodium, potassium, and water retention and decreases in renal function, as well as mild to modest increases in blood pressure (BP) and edema. These deleterious effects are amplified in patients with volume and/or sodium depletion. The concomitant administration of COX-2 inhibitors may destabilize BP control in hypertensive patients treated with antihypertensive agents. In contrast to the normal kidney, which could constitute a target for adverse actions of COX-2 inhibitors, recent experimental studies showed increased renal COX-2 expression in several models of renal injury, such as the remnant kidney, renovascular hypertension, and diabetes, and implicated COX-2 in the progression of renal failure. This suggests that COX-2 inhibitors may confer a renoprotective effect in diverse renal disorders. These intriguing formulations must be delineated further in appropriately designed prospective clinical trials.
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Epstein M. Lercanidipine: a novel dihydropyridine calcium-channel blocker. HEART DISEASE (HAGERSTOWN, MD.) 2001; 3:398-407. [PMID: 11975824 DOI: 10.1097/00132580-200111000-00008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Calcium-channel blockers (CCBs) have been used for the treatment of hypertension for more than 20 years, and recent clinical trials support the efficacy and safety of long-acting dihydropyridine (DHP) CCBs for a wide spectrum of hypertensive patients, including diabetic hypertensive patients. DHP CCBs are effective agents overall and are particularly effective when used in combination with other agents. Lercanidipine is a novel DHP CCB effective for the treatment of mild-to-moderate hypertension. Compared with other DHP CCBs, lercanidipine has a molecular design that imparts greater solubility within the arterial cellular membrane bilayer, membrane-controlled kinetics, and a high cholesterol tolerance factor. These favorable membrane-controlled kinetics impart a gradual onset of vasodilation and a long duration of action. Further, the unique pharmacokinetic and pharmacodynamic properties of lercanidipine appear to contribute to its efficacy and favorable safety profile. In clinical trials in the treatment of mild-to-moderate hypertension, lercanidipine was administered at a starting dose of 10 mg once daily, and increased to 20 mg once daily for nonresponders. Studies have shown that lercanidipine has a 24-hour antihypertensive effect and causes no significant increase in heart rate. Lercanidipine has been shown to be effective in a wide range of hypertensive patients, including mild-to-moderate hypertension, severe hypertension, the elderly, and those with isolated systolic hypertension. It is associated with a low rate of adverse events. Because of its efficacy and favorable safety profile, lercanidipine has the potential to improve blood pressure control in a wide range of patients, including those who have not responded to, or who have been unable to tolerate, other antihypertensive agents.
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Preston RA, Chung M, Gaffney M, Alonso A, Baltodano NM, Epstein M. Comparative pharmacokinetics and pharmacodynamics of amlodipine in hypertensive patients with and without type II diabetes mellitus. J Clin Pharmacol 2001; 41:1215-24. [PMID: 11697754 DOI: 10.1177/00912700122012760] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Recent clinical trials aimed at attenuating complications in diabetes mellitus have generated interest in the impact of drug formulation and altered pharmacokinetics and pharmacodynamics in diabetes. Specifically, it has been proposed that the diabetic state may alter the pharmacokinetics of several cardiovascular drugs, including some calcium antagonists. The present study investigates the effects of diabetes mellitus on the pharmacokinetics and pharmacodynamics of amlodipine in hypertensive subjects with and without diabetes mellitus to determine whether the diabetic state alters these parameters. This trial consisted of a 2-week placebo washout phase, a 2-week titration phase, and a 2-week maintenance phase. Study patients included 18 hypertensive patients with type II diabetes mellitus and 10 nondiabetic hypertensive patients. Blood samples were collected after administration of amlodipine and AUC, Cmax, and tmax were determined. The acute 24-hour pharmacodynamic response to amlodipine was assessed by blood pressure and telemetric heart rate measurements. There were no significant differences for either amlodipine 5 or 10 mg in AUC (p = 0.40 for 5 mg; p = 0.59 for 10 mg), Cmax (p = 0.41 for 5 mg; p = 0.45 for 10 mg), and tmax (p = 0.79 for 5 mg; p = 0.67 for 10 mg) between diabetic and nondiabetic hypertensive subjects. Similarly, the 24-hour pharmacodynamic effects of amlodipine on systolic blood pressure, diastolic blood pressure, and heart rate did not differ between diabetic and nondiabetic subjects as assessed by repeated-measures analysis of variance. Because of the theoretical basis for anticipating that diabetes mellitus may provoke important pharmacokinetic and pharmacodynamic alterations, our study provides an important database in clearly demonstrating that the diabetic milieu did not alter the pharmacokinetics or pharmacodynamics of amlodipine.
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Howarth D, Epstein M, Lan L, Tan P, Booker J. Determination of the optimal minimum radioiodine dose in patients with Graves' disease: a clinical outcome study. EUROPEAN JOURNAL OF NUCLEAR MEDICINE 2001; 28:1489-95. [PMID: 11685491 DOI: 10.1007/s002590100621] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2001] [Accepted: 07/12/2001] [Indexed: 10/27/2022]
Abstract
The study was performed under the auspices of the International Atomic Energy Commission, Vienna, Austria, with the aim of determining the optimal minimum therapeutic dose of iodine-131 for Graves' disease. The study was designed as a single-blinded randomised prospective outcome trial. Fifty-eight patients were enrolled, consisting of 50 females and 8 males aged from 17 to 75 years. Each patient was investigated by clinical assessment, biochemical and immunological assessment, thyroid ultrasound, technetium-99m thyroid scintigraphy and 24-h thyroid 131I uptake. Patients were then randomised into two treatment groups, one receiving 60 Gy and the other receiving 90 Gy thyroid tissue absorbed dose of radioiodine. The end-point markers were clinical and biochemical response to treatment. The median follow-up period was 37.5 months (range, 24-48 months). Among the 57 patients who completed final follow-up, a euthyroid state was achieved in 26 patients (46%), 27 patients (47%) were rendered hypothyroid and four patients (7%) remained hyperthyroid. Thirty-four patients (60%) remained hyperthyroid at 6 months after the initial radioiodine dose (median dose 126 MBq), and a total of 21 patients required additional radioiodine therapy (median total dose 640 MBq; range 370-1,485 MBq). At 6-month follow-up, of the 29 patients who received a thyroid tissue dose of 90 Gy, 17 (59%) remained hyperthyroid. By comparison, of the 28 patients who received a thyroid tissue dose of 60 Gy, 17 (61%) remained hyperthyroid. No significant difference in treatment response was found (P=0.881). At 6 months, five patients in the 90-Gy group were hypothyroid, compared to two patients in the 60-Gy group (P=0.246). Overall at 6 months, non-responders to low-dose therapy had a significantly larger thyroid gland mass (respective means: 35.9 ml vs 21.9 ml) and significantly higher levels of serum thyroglobulin (respective means: 597.6 microg/l vs 96.9 microg/l). Where low-dose radioiodine treatment of Graves' disease is considered, a dose of 60 Gy will yield a 39% response rate at 6 months while minimising early hypothyroidism. No significant advantage in response rate is gained by using a dose of 90 Gy. For more rapid therapeutic effect at the expense of an increased rate of hypothyroidism, doses in excess of 120 Gy may be required. Ultrasound determination of thyroid mass and measurement of serum thyroglobulin levels may be predictive of those patients who will be less responsive to low-dose therapy.
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Epstein M, Tobe S. What is the optimal strategy to intensify blood pressure control and prevent progression of renal failure? Curr Hypertens Rep 2001; 3:422-8. [PMID: 11551378 DOI: 10.1007/s11906-001-0061-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Recent clinical trials clearly demonstrate that patients with diabetes and hypertension, and patients with renal disease and hypertension, should have their blood pressure lowered intensively. A recent analysis of long-term clinical trials over the past 8 years clearly demonstrates that the lower the blood pressure over a range of values, the greater the preservation of renal function. It is also readily apparent that monotherapy does not suffice in attaining these more intensified goals. A review of five clinical trials in the recent National Kidney Foundation consensus report demonstrates that patients randomized to the lower level of blood pressure required an average of 3.2 different antihypertensive medications taken daily. Consequently, it is evident that the question is no longer what the initial preferred monotherapy should be, but rather what should be the optimal drug to add to an angiotensin converting enzyme inhibitor or angiotensin receptor blocker. In this paper we review data from several recent studies clearly indicating that to achieve goal blood pressure in the clinical setting of metabolic disarray and hyperglycemia, long-acting calcium antagonists constitute an excellent add-on agent for enhancing efficacy. We anticipate that the data that will accrue from the IDNT and RENAAL studies will further delineate the renal effects of dihydropyridine calcium antagonists.
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Glück T, Silver J, Epstein M, Cao P, Farber B, Goyert SM. Parameters influencing membrane CD14 expression and soluble CD14 levels in sepsis. Eur J Med Res 2001; 6:351-8. [PMID: 11549517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
INTRODUCTION Membrane (mCD14) and soluble (sCD14) CD14 are pattern recognition receptors for bacterial cell wall fragments. They play an important role in the generation of the innate immune response against bacterial pathogens. Differential expression of these receptors may be relevant for the clinical course of patients with sepsis. PATIENTS AND METHODS 32 patients with an early onset of sepsis (duration of symptoms < 24h) were examined repeatedly by flow cytometry for expression of mCD14, and by ELISA for levels of sCD14, leukocyte elastase and C-reactive Protein (CRP). RESULTS At study entry, mCD14 expression was reduced in all patients with sepsis, but returned to normal levels during the course of the disease in survivors only. mCD14 was found to be inversely correlated with severity of disease, leukocyte elastase, and C-reactive protein. Among patients with severe disease and Apache II scores >or= 20, sCD14 levels at study entry were significantly higher in those who survived by day 28, as compared to non-survivors (p = 0.02). CONCLUSION The data presented are compatible with a recently published hypothesis derived from in vitro experiments suggesting that leukocyte elastase may be responsible for cleavage of mCD14 from the monocyte surface. The data also suggest that higher sCD14 levels may be beneficial in sepsis. Persistently reduced mCD14 expression seems to be a marker for severity of disease in patients with sepsis.
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