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Epstein AM, Hall JA, Tognetti J, Son LH, Conant L. Using proxies to evaluate quality of life. Can they provide valid information about patients' health status and satisfaction with medical care? Med Care 1989; 27:S91-8. [PMID: 2921889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Instruments using interview data to measure health status have been increasingly used to measure patient outcomes. To assess the potential utility of proxy responses about health status when subjects are unable to respond, the authors compared the responses of 60 subject and proxy pairs on instruments measuring overall current health, functional status, social activity, emotional health, and satisfaction with medical care. Proxies were asked to respond as they thought the subject would. Subject and proxy responses were strongly correlated with each other for overall health, functional status, social activity, and emotional health (P less than .001), and moderately correlated for satisfaction (P less than .005). Proxies reported lower emotional health and satisfaction than did subjects (P less than .005). Proxy and subject mean responses were generally similar for overall health, functional status, and social activity. However, those proxies who spent more time per week helping the subject rated the subject's functional status and social activity as more impaired than did the subject (P less than .05). Subjects who had poorer overall health tended to rate their health relatively lower than did the proxies (P less than .05). These results suggest that use of proxies intermingled with subjects to measure health status through interview may lead to biased results.
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Hall JA, Meisterling EM, Lewis PE, Dailey RA. Formation of ovarian follicular cysts and corpora lutea after treatment with antihistamine or indomethacin in prepubertal gilts. Biol Reprod 1989; 40:565-9. [PMID: 2569331 DOI: 10.1095/biolreprod40.3.565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Roles of histamine and prostaglandins in the induction of ovarian cysts after unilateral ovarian manipulation (MAN) and in the process of ovulation were evaluated in prepubertal gilts treated with pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Administration of pyrilamine maleate, an H1 receptor antagonist, before MAN or hCG injection reduced the number of cysts formed but did not alter ovulation rate. Administration of cimetidine, an H2 receptor antagonist, failed to alter the incidence, number, or diameters of cysts formed in response to MAN or the ovulation rate on non-MAN ovaries. Administration of indomethacin, an inhibitor of prostaglandin synthesis, before MAN or hCG injection did not alter the incidence, number, or diameters of cysts formed on MAN ovaries but reduced the number of corpora lutea on non-MAN ovaries. Excessive accumulation of fluid in ovarian cysts apparently was mediated by histamine interacting with the H1-type receptor. Enhanced secretion of prostaglandins produced by the cyclooxygenase pathway did not contribute to development of ovarian cysts but, unlike histamine, was required for formation of corpora lutea in prepubertal gilts treated with PMSG and hCG.
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Hall JA, Epstein AM, McNeil BJ. Multidimensionality of health status in an elderly population. Construct validity of a measurement battery. Med Care 1989; 27:S168-77. [PMID: 2921884 DOI: 10.1097/00005650-198903001-00014] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Although health is generally accepted to be a multidimensional construct, the relationship among various domains has not been well defined. To understand this issue better we used principal components analysis to examine the relations among a set of health status measures gathered on 590 elderly members of a health maintenance organization (HMO). These included functional health, emotional health, social activity within and outside of the family, and cognitive functioning (all based on patient interview), physicians' ratings of patients' health, and chart-derived data on physiologic health. Support was obtained for the umbrella concept of "health" as well as for six subcomponents: functional health, emotional health, physiologic health, both kinds of social activity, and cognitive functioning. Patients' ratings of their overall physical and mental health were related to functional, physiologic, and emotional health factors, whereas physicians' ratings of overall physical and mental health were never related to the emotional health factor. This suggests that patients may hold a broader frame of reference in gauging overall health than physicians do.
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Davenport AP, Nunez DJ, Hall JA, Kaumann AJ, Brown MJ. Autoradiographical localization of binding sites for porcine [125I]endothelin-1 in humans, pigs, and rats: functional relevance in humans. J Cardiovasc Pharmacol 1989; 13 Suppl 5:S166-70. [PMID: 2473298 DOI: 10.1097/00005344-198900135-00045] [Citation(s) in RCA: 144] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Endothelin-1 (ET-1) is a recently discovered 21 amino acid peptide with potent vasoconstrictor properties. So far, its expression has been found only in porcine aorta, whereas its putative role as the endothelium-derived constricting factor (EDCF) would require it to be expressed and active in most vascular beds. We have used quantitative receptor autoradiography on pig, rat, and some human tissues to determine the distribution and localization of specific binding sites for ET-1. In some cases where binding sites were found, studies were performed to determine whether these are likely to be functional receptors. Binding sites for ET-1 have been found in heart (nerves greater than atria greater than ventricle greater than coronary arteries), kidney (glomeruli greater than papilla), adrenal (zona glomerulosa greater than medulla), cerebellum, spinal cord, gut, spleen, and lung. The binding of [125I]ET-1 was displaced at all these sites by unlabeled ET-1 but not by nitrendipine, apamin, and other vasoconstrictor peptides. ET-1 contracted strips of human coronary artery at an EC50 of 15 nM, with a maximal contraction 130% that of K+. A positive inotropic effect was found in strips of human atria (EC50 = 1 nM), which was not blocked by alpha- or beta-blockade. The widespread distribution of its binding sites suggests a more extensive role than control of vascular tone.
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Hall JA, Oppenheim RW, Schachat FH. Changes in myosin and C-protein isoforms proceed independently of the conversion to singly innervated neuromuscular junctions in developing pectoral muscle. Dev Biol 1988; 130:591-8. [PMID: 2904388 DOI: 10.1016/0012-1606(88)90354-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Changes in contractile protein expression during myogenesis are usually categorized as developmentally programmed or neuronally dependent. Studies on aneurogenic chick embryos indicated that the neuronally dependent phase begins at about Embryonic Day 15, immediately prior to the fetal transition in myosin and C-protein expression. The prime candidate for the neuronal event that induces the fetal transition is the conversion to the adult form of singly innervated neuromuscular junctions (NMJs), which occurs contemporaneously with the fetal transition. Using curare to inhibit the conversion to focal innervation, we find that the fetal transition proceeds unimpaired, demonstrating that there is no causal link between the fetal transition and the conversion to focal innervation. Furthermore, because the doses of curare used inhibit motor activity by more than 80%, the fetal transition can occur in the absence of normal levels of motor activity. These observations show that the fetal transition in ovo is not induced by either a specific change in innervation or use. Rather, the dependence on innervation seems to be a consequence of the need for muscle activity to prevent atrophy, and the fetal transition appears to have characteristics more like the preprogrammed contractile protein transitions that precede it.
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Booze RM, Hall JA, Cress NM, Miller GD, Davis JN. DSP-4 treatment produces abnormal tyrosine hydroxylase immunoreactive fibers in rat hippocampus. Exp Neurol 1988; 101:75-86. [PMID: 2899031 DOI: 10.1016/0014-4886(88)90066-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
DSP-4 has been used as selective toxin for central norepinephrine (NE) systems. The depletion of NE by DSP-4 is though to result from neurotoxic destruction of locus coeruleus terminals and axons. We have used tyrosine hydroxylase immunocytochemistry (TH-IR), silver stains for neural degeneration, and electron microscopy to examine the morphological effects of DSP-4 treatment on the rat hippocampus. Animals survived for either 2 or 5 weeks after DSP-4 treatment. DSP-4 depleted hippocampal norepinephrine levels to 15% of control values. Abnormally enlarged TH-IR fibers were found in the hippocampus of DSP-4-treated animals. No evidence of fiber degeneration was found following light or electron microscopic examination of the dentate hilus in DSP-4-treated animals. These data suggest that DSP-4 treatment does not destroy NE terminals, but may produce an intraneuronal lesion leading to an accumulation of TH and a depletion of norepinephrine within the terminal fields.
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Abstract
This article summarizes the results of 41 independent studies containing correlates of objectively measured provider behaviors in medical encounters. Provider behaviors were grouped a priori into the process categories of information giving, questions, competence, partnership building, and socioemotional behavior. Total amount of communication was also included. All correlations between variables within these categories and external variables (patient outcome variables or patient and provider background variables) were extracted. The most frequently occurring outcome variables were satisfaction, recall, and compliance, and the most frequently occurring background variables were the patient's gender, age, and social class. Average correlations and combined significance levels were calculated for each combination of process category and external variable. Results showed significant relations of small to moderate average magnitude between these external variables and almost all of the provider behavior categories. A theory of provider-patient reciprocation is proposed to account for the pattern of results.
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Hall JA, Fettman MJ, Ingram JT. Sodium chloride depletion in a cat with fistulated meningomyelocele. J Am Vet Med Assoc 1988; 192:1445-8. [PMID: 3391839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Decreased serum and CSF chloride concentrations were documented in a 5-year-old Manx cat referred for evaluation of anorexia. Inadequate chloride intake coupled with chloride loss through a fistulated meningomyelocele probably caused chloride deficiency. The inciting cause of anorexia was not determined. The cat was treated with 0.9% NaCl solution. Normal serum and CSF chloride concentrations were restored. Lumbar myelography was performed to delineate the meningocutaneous tract, which then was dissected surgically and was ligated. The cat's body attempted to maintain normal CSF chloride concentration even though the serum chloride concentration was decreased markedly. Calculations made on the basis of rate of CSF production, CSF chloride concentration, and duration of anorexia provided supportive evidence for an active transport system for chloride from plasma to CSF.
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Hall JA, Dornan MC. What patients like about their medical care and how often they are asked: a meta-analysis of the satisfaction literature. Soc Sci Med 1988; 27:935-9. [PMID: 3067368 DOI: 10.1016/0277-9536(88)90284-5] [Citation(s) in RCA: 353] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A meta-analysis of studies on consumer satisfaction with medical care yielded 221 studies that reported relations between satisfaction and other variables, of which 107 reported satisfaction levels for two or more aspects of medical care. A method was developed to derive the relative levels of patient satisfaction with 11 aspects of care across these 107 studies. Humaneness and technical quality of medical care were ranked near the top, while the bottom five ranks were occupied by aspects of care that reflected the provider's attention to other patient needs and the patient's relation to the system as a whole. In addition, it was demonstrated that different aspects of medical care are measured with extremely uneven frequencies in satisfaction instruments.
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Hall JA, Dornan MC. Meta-analysis of satisfaction with medical care: description of research domain and analysis of overall satisfaction levels. Soc Sci Med 1988; 27:637-44. [PMID: 3067359 DOI: 10.1016/0277-9536(88)90012-3] [Citation(s) in RCA: 306] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Consumer satisfaction with medical care was examined in a meta-analysis of 221 studies. For each study, (1) a coding form was filled out that described sample characteristics, design, and instrument methodology, and (2) the study sample's overall satisfaction level was transformed to a 0.00-1.00 scale. This article summarizes the study attributes as compiled from the coding form, presents grand satisfaction means over all studies, and tests for differences in satisfaction between studies that employed different methods of research.
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Hall JA, Allen TA, Fettman MJ. Hyperammonemia associated with urethral obstruction in a dog. J Am Vet Med Assoc 1987; 191:1116-8. [PMID: 3693031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Hyperammonemia was documented in a 10-week-old male Lhasa Apso referred for urethral obstruction and rupture. Results of liver function tests were normal. Staphylococcus sp was isolated from urine. Anomalies of the portal vascular system and hepatic insufficiency are the most common causes of hyperammonemia in the dog. Hyperammonemia, however, in the absence of recognizable concurrent hepatic disease, also may result from urinary stasis and infection with urea-splitting organisms.
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Abstract
This paper investigates the association between physicians' interviewing styles and medical information obtained during simulated patient encounters. The sources of data are audiotapes and transcripts of two standardized patient cases presented by trained patient simulators to 43 primary care practitioners. Transcripts were scored for physician proficiency using expert-generated criteria and were content-analyzed to assess the process of communication and information content. Relevant patient disclosure was also scored from the transcripts based on expert-generated criteria. Findings were: 1) On the whole, physicians elicited only slightly more than 50% of the medical information considered important according to expert consensus, with a range from 9% to 85%. 2) Both open and closed questions were substantially related to patient disclosure of medical information to the physician, but open questions were substantially more so (Pearson correlations of 0.37 and 0.72, respectively). 3) Patient education, particularly information regarding prognosis, cause, and prevention, was substantially related to patient disclosure of medical information to the physician (Pearson correlations of 0.44, 0.36, and 0.34, respectively). 5) Finally, clinical expertise was only weakly associated with patient disclosure of medical information to the physician (Pearson correlation of 0.16).
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Fatouros PP, Wist AO, Kishore PR, DeWitt DS, Hall JA, Keenan RL, Stewart LM, Marmarou A, Choi SC, Kontos HA. Xenon/computed tomography cerebral blood flow measurements. Methods and accuracy. Invest Radiol 1987; 22:705-12. [PMID: 3679761 DOI: 10.1097/00004424-198709000-00003] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We performed a series of five baboon experiments to compare cerebral blood flow measured with an improved stable xenon/CT method and the radiolabelled microsphere technique at a PaCO2 of 40 mm Hg. The xenon/CT method was implemented by fitting the arterial xenon uptake with a double exponential function, by measuring the oxygen and carbon dioxide concentrations continuously during each breath and by taking into account the lung-to-brain transit time of xenon. The time of xenon inhalation was extended to 30 minutes to obtain more reliable estimates of CBF in white matter regions. The results indicate an overall correlation coefficient of 0.92 between the two methods and good numeric agreement.
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Roter DL, Hall JA, Katz NR. Relations between physicians' behaviors and analogue patients' satisfaction, recall, and impressions. Med Care 1987; 25:437-51. [PMID: 3695654 DOI: 10.1097/00005650-198705000-00007] [Citation(s) in RCA: 248] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This paper investigates associations between physicians' task-oriented and socioemotional behaviors, on the one hand, and analogue patients' satisfaction, recall of information, and global impressions. The study is based on role-playing subjects' responses to interactions between physicians and simulated patients. Audiotapes of two standardized patient cases presented by trained patient simulators to 43 primary care physicians were rated by role-playing patients (N = 258), and electronically filtered excerpts from the encounters were rated for vocal affect by 37 independent judges. Content analysis was made of the visits' transcripts to assess interaction process and to identify all medical information communicated. Finally, speech error rate was calculated from a combination of audiotape and transcript. Findings revealed that role-playing patients clearly distinguished task from socioemotional behaviors of the physicians, and a consistent pattern of association emerged between physicians' task behaviors and role-playing patients' satisfaction, recall, and impressions. Within the task domain, patient-centered skills (i.e., giving information and counseling) were consistently related to patient effects in a positive direction, but physician-centered behaviors (i.e., giving directions and asking questions) demonstrated the opposite relationship. A negative pattern of association was also evident between physicians' socioemotional behaviors and patient effects.
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Abstract
This paper investigates associations among physicians' task-oriented and socioemotional behaviors during the medical encounter. The study is an analogue, using as source data the audiotapes and transcripts of two standardized patient cases presented by trained patient simulators to 43 primary care practitioners. Transcripts were scored for physician proficiency and were content-analyzed to assess the process of communication and information content. Physicians' speech errors were counted, and vocal affect ratings were made of filtered audiotape excerpts. Physician communications reflected by these measures were classified as task-oriented or socioemotional. Findings indicated: 1) Most aspects of physician style were reliable across visits. 2) Physicians adopted either a patient-oriented or a physician-oriented approach to task performance, as characterized by giving information and counseling versus giving directions and asking questions, respectively. 3) Verbal and nonverbal socioemotional measures were not related. 4) Physicians tended to adopt either a style characterized by information-giving and proficiency or a social orientation with patients. 5) Physicians who were more medically informative had more interested and anxious voices compared with the less informative physicians. Thus, although the more medically informative physicians spent less time making socioemotional utterances, they had a voice quality that may compensate for that neglect.
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Hall JA, Magne ML, Twedt DC. Effect of acepromazine, diazepam, fentanyl-droperidol, and oxymorphone on gastroesophageal sphincter pressure in healthy dogs. Am J Vet Res 1987; 48:556-7. [PMID: 2884907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Treatment of healthy dogs with 4 commonly used psychotropic or analgesic agents significantly decreased resting gastroesophageal sphincter pressure (GESP). Acepromazine decreased GESP by 35% (P = 0.02); oxymorphone decreased GESP by 38% (P less than 0.005); diazepam decreased GESP by 42% (P = 0.005); and fentanyl-droperidol decreased GESP by 40% (P = 0.03). Therefore, esophageal manometric evaluation of gastroesophageal sphincter function should not be preceded by administration of these drugs.
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Barnard RJ, Hall JA, Chaudhari A, Miller JE, Kirschenbaum MA. Effects of a low-fat, low-cholesterol diet on serum lipids, platelet aggregation and thromboxane formation. PROSTAGLANDINS, LEUKOTRIENES, AND MEDICINE 1987; 26:241-52. [PMID: 3472254 DOI: 10.1016/0262-1746(87)90034-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The purpose of this study was to test the effects of a low-fat, low-cholesterol diet on serum lipids, platelet aggregation, thromboxane formation and blood pressure. Fifteen hyperlipidemic males with normal blood pressure were treated for 2 weeks. Resting supine blood pressure, total serum cholesterol, HDL-cholesterol, the ratio of total cholesterol/HDL-cholesterol and triglycerides all were significantly reduced. The maximum aggregation and velocity of aggregation for isolated platelets stimulated with either ADP or collagen was significantly reduced. Thromboxane formation during 5 min of platelet aggregation with collagen or ADP was also significantly reduced. These results have important implications for hypertension and atherosclerotic cardiovascular disease.
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Hall JA. The use of laser holograms in study model storage. AUSTRALIAN ORTHODONTIC JOURNAL 1987; 10:36. [PMID: 3479976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Epstein AM, Hall JA, Besdine R, Cumella E, Feldstein M, McNeil BJ, Rowe JW. The emergence of geriatric assessment units. The "new technology of geriatrics". Ann Intern Med 1987; 106:299-303. [PMID: 3800188 DOI: 10.7326/0003-4819-106-2-299] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Previous studies have suggested that geriatric assessment units may provide important benefits to the care of elderly persons. In early 1985 we surveyed personnel at 104 (91%) of the existing 114 geriatric assessment units associated with medical schools and Veterans Administration medical centers for information on the units' development and operation. Although almost 80% of the units were hospital based, most (61%) provided care for outpatients. Nearly half (47%) began operation in 1983 or later; of those in existence before 1983, two thirds have increased their capacity since then. The types of personnel and their training differed substantially among units. Fifty percent of the physicians had had no formal training in geriatrics. Of the 104 units, 99 (95%) did routine assessment. The estimated time spent per new patient in outpatient units was 2.7 +/- 2.1 (SD) hours. These data suggest that geriatric assessment units are proliferating rapidly, have differing structures, and consume substantial resources. Further efforts are needed to define their optimal structure, targets, and function.
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Smithson LV, Lipper MH, Hall JA. Paranasal sinus involvement in thalassemia major: CT demonstration. AJNR Am J Neuroradiol 1987; 8:564-5. [PMID: 3111221 PMCID: PMC8331860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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247
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Lottenberg R, Hall JA, Pautler E, Zupan A, Christensen U, Jackson CM. The action of factor Xa on peptide p-nitroanilide substrates: substrate selectivity and examination of hydrolysis with different reaction conditions. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 874:326-36. [PMID: 3790574 DOI: 10.1016/0167-4838(86)90032-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Kinetic parameters for the action of bovine Factor Xa (EC 3.4.21.22) on 25 commercially available peptide p-nitroanilides have been determined. The selectivity constant, kc/Km, ranges from 1.5 X 10(1) to 2 X 10(6) M-1 X s-1 for the poorest and the best substates, respectively. The best substrates for Factor Xa were identified as those with arginine in the P1 position, and glycine in the P2 position. Quantitative distinction between lysine and arginine in the P1 position and other amino acids in the P2-P4 positions of the substrate is reported from the changes in the kinetic parameters for substrates differing in only a single amino acid in these positions. Effect of NaCl and CaCl2 concentrations and temperature on the action of Factor Xa on selected substrates have been assessed. Km values for Factor Xa hydrolysis of most substrates are greater than 100 microM. Solubility of the substrates consequently restricts measurements of reaction velocities to concentrations lower than desirable for optimally determining kc. Comparison of these kinetic parameters for Factor Xa with those of thrombin (Lottenberg, R., Hall, J.A., Blinder, M., Binder, E. and Jackson, C.M. (1983) Biochim. Biophys. Acta 742,539-557) for these same substrates indicates that the greater hydrolytic efficiency of thrombin is due primarily to lower Km values.
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248
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Hall JA. Toward a Jungian theory of hypnosis. AMERICAN JOURNAL OF CLINICAL HYPNOSIS 1986; 29:109-15. [PMID: 3776894 DOI: 10.1080/00029157.1986.10402693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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249
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Abstract
A case of T-1, T-2 disc herniation is reported. The patient presented with diminished hand strength, medial arm and shoulder pain, and medial arm, forearm, and hand paresthesias. After surgical decompression and removal of a disc fragment, the patient made a complete recovery. Routine cervical myelography was considered inadequate in view of this patient's symptoms. High thoracic myelography followed by computed tomographic scanning should be considered for patients with this presentation. Improved diagnosis with myelography and computed tomography is discussed.
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250
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Latallo ZS, Hall JA. Reaction of thrombins with human antithrombin III. I. Enzyme activity losses unrelated to the inhibitory reaction and their prevention. Thromb Res 1986; 43:507-21. [PMID: 3750277 DOI: 10.1016/0049-3848(86)90071-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Adsorption loss of thrombin may produce considerable systematic error when quantitative evaluation of its reaction with antithrombin III is based on measurements of changes in enzyme activity with time. At 25 degrees C, pH 7.8 (0.1 M NaCl, 0.01 M TRIS, 0.01 M HEPES) glass, siliconized glass, polypropylene and polystyrene surfaces adsorb thrombin in a similar manner. Its adsorption is a saturation reaction reaching an equilibrium after about three hours. At initial concentrations of enzyme convenient for assay with chromogenic substrate (10 nM or less) a large fraction of activity is lost. Binding of alpha thrombin to polypropylene is very tight. The association constants (Ka) were found to be 12.6 X 10(9) M-1 and 4.0 X 10(9) M-1 for human and bovine alpha thrombin respectively. The adsorbed enzyme has hardly any ability to hydrolyze chromogenic substrate. A small part of its activity can be recovered by displacement with PEG 6000, more when the substrate is present. The addition of non-ionic detergents and continuous stirring allows recovery of up to 30% of the enzyme activity and accelerates this process. Complete and long term (more than 20 hours at 25 degrees C) prevention of adsorption loss of human alpha and bovine alpha and beta thrombin at pH between 7.0-8.3 is achieved by the addition of 0.1% PEG 6000 to the buffer and use of tubes precoated with PEG 20,000. Alternative use of non-ionic detergents (BRIJ-35, TRITON X-100) to modify the solvent also appears effective but their possible interference with reactions studied should be borne in mind.
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