501
|
Manns A, Chan C, Miralles R. Influence of group function and canine guidance on electromyographic activity of elevator muscles. J Prosthet Dent 1987; 57:494-501. [PMID: 3471962 DOI: 10.1016/0022-3913(87)90024-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A comparative EMG study was done between two types of occlusal guidances: group function and canine guidance. The purpose was to determine which of the two occlusal schemes causes a greater reduction in muscle activity and thereby a decrease in muscle tension in eccentric mandibular positions. Full-coverage occlusal splints were made for six test subjects with normal function of the stomatognathic system. Left- and right-side integrated EMG recordings were made of the masseter and temporal muscles during static (clenching) and dynamic (lateral excursion and clenching) maximal contractions. The results showed an EMG activity reduction of the elevator muscles with group function relative to their activity in centric occlusion. A more marked reduction was observed on the mediotrusive side, mainly in the temporal muscle. With canine guidance, the reduction in elevator muscle activity is much greater, more significant, and mainly in the temporal muscle of the mediotrusive side. The clinical implications of this study suggest the use of canine guidance in laterotrusion for therapy with full-coverage occlusal splints.
Collapse
|
502
|
Chan C, Cho MH, Hershkowitz N, Intrator T. Experimental observation of slow ion acoustic double layers. PHYSICAL REVIEW LETTERS 1986; 57:3050-3053. [PMID: 10033941 DOI: 10.1103/physrevlett.57.3050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
503
|
Heng MC, Chan C, Kloss SG. Electron microscopic findings in ichthyosis secondary to sarcoidosis. Australas J Dermatol 1986; 27:127-30. [PMID: 3632509 DOI: 10.1111/j.1440-0960.1986.tb00308.x] [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: 01/06/2023]
|
504
|
Chan C, Weber H. Plaque retention on teeth restored with full-ceramic crowns: a comparative study. J Prosthet Dent 1986; 56:666-71. [PMID: 3464748 DOI: 10.1016/0022-3913(86)90140-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Plaque accumulation was determined by using the plaque index of Silness and Löe on 150 crowns in 19 patients. The plaque indices for individual crowns in a quadrant were compared to the average plaque index of the quadrant in which the crowns were inserted (quadrant plaque index = 100%). This comparative study showed that Cerestore full-ceramic crowns have little soft debris retention (32%). Ceramometal crowns (90%), natural teeth (110%), cast gold restorations (148%), and acrylic resin veneer crowns (152%) have increasing plaque retention. The results indicate that ceramics are easily cleaned and exhibit low plaque retention. Increasing the area of ceramic surfaces on restorations decreases plaque retention.
Collapse
|
505
|
Janicak PG, Davis JM, Chan C, Altman E, Hedeker D. Failure of urinary MHPG levels to predict treatment response in patients with unipolar depression. Am J Psychiatry 1986; 143:1398-402. [PMID: 3777227 DOI: 10.1176/ajp.143.11.1398] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The authors studied 64 depressed patients who were receiving a vanillylmandelic acid (VMA)-free diet and underwent a washout period (mean, 24 days) before treatment. During the washout period, a mean of 2.5 multiple 24-hour urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) samples per patient were collected. Thirty-four patients were then treated with a "noradrenergic" antidepressant only (e.g., imipramine), and seven were treated with a "serotonergic" antidepressant only (e.g., amitriptyline). Twelve patients received combined drug treatment and 11 others spontaneously remitted. Response to treatment was rated on a clinical global evaluation scale from 1 (little or no response) to 7 (maximum response). No relationship was found between response to treatment, type of treatment, and the average pretreatment 24-hour urinary MHPG level. The authors thus failed to confirm the hypothesis that a low MHPG level predicts response to antidepressant treatment.
Collapse
|
506
|
Unger A, Goetzman BW, Chan C, Lyons AB, Miller MF. Nutritional practices and outcome of extremely premature infants. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1986; 140:1027-33. [PMID: 3092638 DOI: 10.1001/archpedi.1986.02140240073029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We analyzed the records of 182 newborns with birth weights under 1000 g, who survived longer than seven days, to determine risk factors for subacute mortality and morbidity. Statistical analysis using logarithm-linear modeling was used to identify complex interactions and to minimize confounding. Nosocomial infection, necrotizing enterocolitis, male gender, and chronic lung disease (CLD) were identified as independent risk factors for subacute mortality. Male gender and CLD were associated with increased mortality only among patients who received parenteral nutrition (PN). Moreover, PN, rather than enteral nutrition (EN), was a risk factor for delayed growth, nosocomial infection, and CLD. Delayed initiation of EN was associated with decreased necrotizing enterocolitis risk only among male infants with birth weights under 775 g. Our results do not support elective withholding of EN in other groups of extremely low-birth-weight infants. We conclude that indications for PN and for withholding initiation of EN in very-very-low-birth-weight infants need to be established by prospective studies.
Collapse
MESH Headings
- Body Weight
- Chronic Disease
- Cross Infection/etiology
- Cross Infection/mortality
- Enteral Nutrition
- Enterocolitis, Pseudomembranous/epidemiology
- Enterocolitis, Pseudomembranous/etiology
- Fasting/adverse effects
- Humans
- Infant Mortality
- Infant Nutritional Physiological Phenomena
- Infant, Low Birth Weight
- Infant, Newborn
- Infant, Premature
- Infant, Premature, Diseases/etiology
- Infant, Premature, Diseases/mortality
- Intensive Care Units, Neonatal
- Lung Diseases/etiology
- Parenteral Nutrition/adverse effects
- Retrospective Studies
- Risk
- Sex Factors
- Time Factors
Collapse
|
507
|
Hayasaki M, Hanabayashi T, Ri J, Takada Y, Ito K, Noda K, Iida M, Chan C, Yamada Y, Osugi S. [Pharmacokinetic and clinical studies of cefotiam in the perinatal period]. THE JAPANESE JOURNAL OF ANTIBIOTICS 1986; 39:2497-518. [PMID: 3467091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Patients, who had undergone cesarean sections, and those who had experienced premature rupture of membranes, received cefotiam (CTM) and the clinical efficacy and the safety for mothers and fetuses were investigated. At the same time, pharmacokinetic analysis was done to study the maternal fetal transfer. Following results were observed. In cases of premature rupture of membranes, the maternal-fetal transfer ratio after intravenous administrations of CTM was 50.3% at a dosage of 1 g. Maternal and fetal serum concentrations of CTM were maintained higher levels than the MIC80 (0.78 micrograms/ml) against major pathogens excluding anaerobic of gynecologic-obstetric infections and were maintained up to 5.87 hours and 6.15 hours in mothers and fetuses, respectively. The CTM was administered once every 12 hours at a dosage of 1 g to 38 cases up to the 3rd or 4th day of puerperium after the rupture of membranes. Also, the CTM was administered up to times of delivery to another 20 cases, in one of which the fetus developed pneumonia. The maternal-fetal prophylactic effect was recognized in 98.3% (57/58) of cases. Forty-three cesarean section cases received CTM at a dosage level of 1 g by one-hour intravenous drip infusion in the following manner: after surgery to the 4th day, twice a day; from the 5th to the 7th day, once a day. Postoperative prophylactic effect against infection was achieved in all the cases. In 1 case, a slight transient elevation in the maternal GOT was observed. Neonatal jaundice with total bilirubin levels higher than 15.0 mg/dl was observed in 19 neonates (32.8%) in the group in which premature rupture of the membranes had occurred. However, the cause/effect relationship between CTM and the total bilirubin levels is unclear. The maternal-fetal transition of CTM was excellent, and the safety toward the fetus and neonate was high. When an antimicrobial activity and pharmacokinetics are considered, CTM will be a useful drug in the treatment of perinatal infections.
Collapse
|
508
|
Malek TR, Ortega G, Chan C, Kroczek RA, Shevach EM. Role of Ly-6 in lymphocyte activation. II. Induction of T cell activation by monoclonal anti-Ly-6 antibodies. J Exp Med 1986; 164:709-22. [PMID: 3489060 PMCID: PMC2188391 DOI: 10.1084/jem.164.3.709] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The Ly-6 locus controls the expression and/or encodes for alloantigenic specificities found primarily on subpopulations of murine T and B lymphocytes. We have recently identified and characterized a new rat mAb, D7, that recognizes a nonpolymorphic Ly-6 specificity. After crosslinking by anti-Ig reagents or by Fc receptor-bearing accessory cells, mAb D7 could induce IL-2 production from T cell hybridomas, and in the presence of PMA could trigger a vigorous proliferative response in resting peripheral T cells. The addition of mAb D7 to cultures of antigen- and alloantigen-, but not mitogen-stimulated T cells resulted in a marked augmentation of the proliferative response. A number of other well-characterized mAbs to Ly-6 locus products could also stimulate a T cell proliferative response after crosslinking by anti-Ig and in the presence of PMA. These results strongly suggest that Ly-6 molecules may play a critical role in the T cell activation cascade, either as receptors for an unidentified soluble or cell-associated ligand or as transducing molecules that modulate signals initiated by antigen stimulation of the T3-Ti complex.
Collapse
|
509
|
Orman SV, Schechter GP, Whang-Peng J, Guccion J, Chan C, Schulof RS, Shalhoub RJ. Nephrotic syndrome associated with a clonal T-cell leukemia of large granular lymphocytes with cytotoxic function. ARCHIVES OF INTERNAL MEDICINE 1986; 146:1827-9. [PMID: 3489448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A 51-year-old man presented with a T-cell leukemia of large granular lymphocytes and rapidly developed a nephrotic syndrome due to presumptive minimal-change glomerulopathy. The E-rosette+, Ia+ cells demonstrated cytotoxic activity similar to that of natural killer lymphocytes but lacked other T-subset markers, except that one third of them bore Fc(IgG) receptors. Cytogenetic analysis revealed loss of chromosome 10 and the translocation (1;10)(p11;q11) in all metaphases. Regression of the leukemia after chemotherapy was accompanied by a dramatic resolution of the nephrotic syndrome, suggesting that the activated granular lymphocytes induced the renal lesion. The close association of a clonal T-lymphoproliferative disorder with minimal-change nephrotic syndrome lends further support to current views implicating activated T cells or their products in the pathogenesis of this glomerulopathy.
Collapse
|
510
|
Chan C, Okun E. The question of ocular tolerance to intravitreal liquid silicone. A long-term analysis. Ophthalmology 1986; 93:651-60. [PMID: 3725324 DOI: 10.1016/s0161-6420(86)33685-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The authors report a retrospective review of 407 eyes that received intravitreal liquid silicone between 1961 and 1984. Initial anatomical success was noted in 270 eyes (66.3%), while initial functional success was achieved in 103 eyes (25.3%). Ten years postoperatively, approximately half of the eyes with initial functional success still had functional vision (49.2%). These eyes had less advanced proliferative vitreoretinopathy and fewer inferior breaks than others. Recurrent retinal detachment rather than late complications was the predominant cause of functional failure in those eyes losing functional vision in less than ten years postoperatively. Late complications were common and frequently required therapeutic intervention. Intravitreal liquid silicone was of great benefit to many monocular patients, but of little benefit to the binocular patients in our series.
Collapse
|
511
|
Chan C, Bartolucci A, Brenner D, Presant C, Davila E, Carpenter J, Greco FA, Clamon G, Moore J. Phase II trial of diaziquone in anthracycline-resistant adult soft tissue and bone sarcoma patients: a Southeastern Cancer Study Group Trial. CANCER TREATMENT REPORTS 1986; 70:427-8. [PMID: 3456834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
512
|
Glazer AN, Chan C, Williams RC, Yeh SW, Clark JH. Kinetics of Energy Flow in the Phycobilisome Core. Science 1985; 230:1051-3. [PMID: 17814931 DOI: 10.1126/science.230.4729.1051] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Light energy absorbed by the 576 bilin chromophores in the six rods of the phycobilisome of the cyanobacterium Synechocystis 6701 is funneled into a 1.5 x 10(6) dalton core. The 72 bilins of the core function as a single unit with respect to the rate-limiting processes for energy flow within these particles.
Collapse
|
513
|
Wassmer P, Chan C, Lögdberg L, Shevach EM. Role of the L3T4-antigen in T cell activation. II. Inhibition of T cell activation by monoclonal anti-L3T4 antibodies in the absence of accessory cells. THE JOURNAL OF IMMUNOLOGY 1985. [DOI: 10.4049/jimmunol.135.4.2237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We have used two monoclonal antibodies (Mab) to the L3T4 antigen to reexplore the role of this molecule in the process of T cell activation. Both Mab (Gk1.5 and 2B6) were capable of inhibiting Con A-induced IL 2 production by a number of antigen-specific T cell hybridomas in an assay system that was free of major histocompatibility complex (MHC) class II antigen-bearing cells. The inhibition produced by the anti-L3T4 Mab was specific, because other Mab to cell surface antigens expressed on the hybridomas were without inhibitory effects. These studies rule out the possibility that the mechanism of inhibition by anti-L3T4 in this model is mediated by blocking interaction of L3T4 with MHC class II products. Taken together, these results and those of other groups of investigators, are most compatible with a dual function for L3T4 in T cell activation. L3T4 might first interact with MHC class II molecules or other molecules on target or accessory cells; L3T4 would subsequently transmit a signal that would regulate the activation process. Mab to L3T4 might exert inhibitory effects at one or both of these steps.
Collapse
|
514
|
Wassmer P, Chan C, Lögdberg L, Shevach EM. Role of the L3T4-antigen in T cell activation. II. Inhibition of T cell activation by monoclonal anti-L3T4 antibodies in the absence of accessory cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1985; 135:2237-42. [PMID: 3897371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We have used two monoclonal antibodies (Mab) to the L3T4 antigen to reexplore the role of this molecule in the process of T cell activation. Both Mab (Gk1.5 and 2B6) were capable of inhibiting Con A-induced IL 2 production by a number of antigen-specific T cell hybridomas in an assay system that was free of major histocompatibility complex (MHC) class II antigen-bearing cells. The inhibition produced by the anti-L3T4 Mab was specific, because other Mab to cell surface antigens expressed on the hybridomas were without inhibitory effects. These studies rule out the possibility that the mechanism of inhibition by anti-L3T4 in this model is mediated by blocking interaction of L3T4 with MHC class II products. Taken together, these results and those of other groups of investigators, are most compatible with a dual function for L3T4 in T cell activation. L3T4 might first interact with MHC class II molecules or other molecules on target or accessory cells; L3T4 would subsequently transmit a signal that would regulate the activation process. Mab to L3T4 might exert inhibitory effects at one or both of these steps.
Collapse
|
515
|
Honda M, Chan C, Shevach EM. Characterization and partial purification of a specific interleukin 2 inhibitor. THE JOURNAL OF IMMUNOLOGY 1985. [DOI: 10.4049/jimmunol.135.3.1834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
To investigate the mechanisms that regulate the action of interleukin 2 (IL 2) and possibly limit its activity, we screened supernatants of mouse spleen cell cultures which had been stimulated with concanavalin A (Con A) for their ability to inhibit IL 2-mediated proliferation of a cloned IL 2-dependent line. Inhibitory activities with m.w. of 10,000 to 12,000 and 60,000 to 80,000 daltons could be identified in supernatants of both L3T4+ and Ly-2+ T cells, but not in supernatants of Con A or lipopolysaccharide-stimulated B cells. Maximal inhibitory activity was observed after 3 to 4 days of stimulation, and this inhibitory activity could be overcome by increasing the stimulatory concentration of IL 2. When the factor was further purified by reverse-phase high pressure liquid chromatography, it eluted as a single peak with an m.w. of 11,000 to 12,000 daltons which inhibited IL 2- but not IL 3-dependent proliferation. The mechanisms by which this new lymphokine might play in the control of the clonal expansion of T lymphocytes are discussed.
Collapse
|
516
|
Malek TR, Chan C, Glimcher LH, Germain RN, Shevach EM. Influence of accessory cell and T cell surface antigens on mitogen-induced IL 2 receptor expression. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1985; 135:1826-33. [PMID: 3926885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We have assessed the inhibitory effects of various monoclonal antibodies on the expression of the IL 2 receptor. Anti-LFA-1, but not anti-Ly-2, markedly inhibited the induction of the IL 2 receptor on the Ly-2+ subset. T-depleted spleen cells, L cells, and B lymphoma cells all functioned as potent accessory cells (AC) for the induction of the IL 2 receptor on L3T4+ T cells. Anti-LFA-1 inhibited the induction of the IL 2 receptor irrespective of the type of AC used. Anti-L3T4 only inhibited the induction of IL 2 receptor expression when L cells were the source of AC. The inhibitory capacity of anti-L3T4 was not related to the expression of Ia on the AC population, because the magnitude of inhibition was comparable in cultures containing either Ia+ or Ia- L cells, whereas no inhibition was seen with either Ia+ or Ia-B lymphoma cells. We conclude from these studies that LFA-1 plays a critical role in mitogen-induced activation of both T cell subsets by promoting both T-AC and T-T interactions. Although anti-L3T4 can inhibit T cell activation in the absence of the recognition of Ia, the mechanism of inhibition and the proposed target molecule for L3T4 on the AC or the T cell have not been determined in our studies. A number of different models for the function of this cell surface antigen are discussed.
Collapse
|
517
|
Honda M, Chan C, Shevach EM. Characterization and partial purification of a specific interleukin 2 inhibitor. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1985; 135:1834-9. [PMID: 3926886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
To investigate the mechanisms that regulate the action of interleukin 2 (IL 2) and possibly limit its activity, we screened supernatants of mouse spleen cell cultures which had been stimulated with concanavalin A (Con A) for their ability to inhibit IL 2-mediated proliferation of a cloned IL 2-dependent line. Inhibitory activities with m.w. of 10,000 to 12,000 and 60,000 to 80,000 daltons could be identified in supernatants of both L3T4+ and Ly-2+ T cells, but not in supernatants of Con A or lipopolysaccharide-stimulated B cells. Maximal inhibitory activity was observed after 3 to 4 days of stimulation, and this inhibitory activity could be overcome by increasing the stimulatory concentration of IL 2. When the factor was further purified by reverse-phase high pressure liquid chromatography, it eluted as a single peak with an m.w. of 11,000 to 12,000 daltons which inhibited IL 2- but not IL 3-dependent proliferation. The mechanisms by which this new lymphokine might play in the control of the clonal expansion of T lymphocytes are discussed.
Collapse
|
518
|
Malek TR, Chan C, Glimcher LH, Germain RN, Shevach EM. Influence of accessory cell and T cell surface antigens on mitogen-induced IL 2 receptor expression. THE JOURNAL OF IMMUNOLOGY 1985. [DOI: 10.4049/jimmunol.135.3.1826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We have assessed the inhibitory effects of various monoclonal antibodies on the expression of the IL 2 receptor. Anti-LFA-1, but not anti-Ly-2, markedly inhibited the induction of the IL 2 receptor on the Ly-2+ subset. T-depleted spleen cells, L cells, and B lymphoma cells all functioned as potent accessory cells (AC) for the induction of the IL 2 receptor on L3T4+ T cells. Anti-LFA-1 inhibited the induction of the IL 2 receptor irrespective of the type of AC used. Anti-L3T4 only inhibited the induction of IL 2 receptor expression when L cells were the source of AC. The inhibitory capacity of anti-L3T4 was not related to the expression of Ia on the AC population, because the magnitude of inhibition was comparable in cultures containing either Ia+ or Ia- L cells, whereas no inhibition was seen with either Ia+ or Ia-B lymphoma cells. We conclude from these studies that LFA-1 plays a critical role in mitogen-induced activation of both T cell subsets by promoting both T-AC and T-T interactions. Although anti-L3T4 can inhibit T cell activation in the absence of the recognition of Ia, the mechanism of inhibition and the proposed target molecule for L3T4 on the AC or the T cell have not been determined in our studies. A number of different models for the function of this cell surface antigen are discussed.
Collapse
|
519
|
Hershkowitz N, Nelson BA, Johnson J, Ferron JR, Persing H, Chan C, Golovato SN, Callen JD, Woo J. Enhancement of the plasma potential by fluctuating electric fields near the ion cyclotron frequency. PHYSICAL REVIEW LETTERS 1985; 55:947-950. [PMID: 10032490 DOI: 10.1103/physrevlett.55.947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
520
|
Abstract
These studies have examined the effects of dl-propranolol, d-propranolol, and metoprolol on aortic atherogenesis in the cholesterol-fed rabbit and have correlated the vascular effects of the drugs with their influence on blood pressure, plasma lipids and lipoproteins, arterial metabolism, and arterial permeability. dl-Propranolol, and, to a lesser extent, d-propranolol, used in clinically relevant doses of 5 mg/kg body weight per day, inhibited the development of aortic atherosclerosis in association with significant reductions in aortic free and esterified cholesterol content. No significant effects of the drugs on blood pressure or on the total amounts or types of circulating lipoproteins were apparent. Accumulation of cholesterol in the liver and adrenal gland was not influenced by propranolol. Aortic acyl CoA:cholesterol acyltransferase and lysosomal enzyme activities were reduced by propranolol administration, but the inhibition may have been secondary to the lesser degrees of atherosclerosis and cholesterol accumulation present. In vitro inhibition of acyl CoA:cholesterol acyltransferase activity by either dl- or d-propranolol was also observed, but occurred only at propranolol concentrations of 10(-3) M or greater. Treatment with dl-propranolol had no significant effect on the rate of transport of labeled albumin across the isolated carotid artery of cholesterol-fed rabbits. Metoprolol administration (6.25 mg/kg body weight per day) had no significant influence on atherogenesis or arterial metabolism in this model. The results suggest that propranolol inhibits in part the development of atherosclerosis in the cholesterol-fed rabbit, and that the effect may be related to a direct action on the arterial wall.
Collapse
|
521
|
Chan C, Smith G, Jacobs RJ. Simulating refractive errors: source and observer methods. AMERICAN JOURNAL OF OPTOMETRY AND PHYSIOLOGICAL OPTICS 1985; 62:207-16. [PMID: 3985114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
There are two principal methods of simulating refractive errors. Either the retinal image can be defocused by an optical system, usually a positive lens, placed in front of an observer's eye (observer method), or the source of the retinal image can be defocused as it is projected onto a screen or photograph (source method). There are significant differences between the two methods, differences that make it difficult to compare results. However, the source method, which is the more artificial, seems to be superior for a number of reasons. The results of these two methods can be compared using a common or interchangeable parameter for specifying the level of defocus. A convenient parameter is the size of the defocused image of a point, measured either in image space (linear or angular diameter on the retina) or in object space (angular diameter of the blur disc projected back into object space), with the angular diameter measured from the respective nodal point of the eye. Methods of measuring the angular blur-disc diameter for both methods are discussed and the validity of the formula omega = D delta L, is investigated, where omega is the angular diameter of the blur disc, D is the observer's pupil diameter, and delta L is the dioptric defocus.
Collapse
|
522
|
Malek TR, Ortega G, Jakway JP, Chan C, Shevach EM. The murine IL 2 receptor. II. Monoclonal anti-IL 2 receptor antibodies as specific inhibitors of T cell function in vitro. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1984; 133:1976-82. [PMID: 6432904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We assessed the dependency of a variety of immune responses for IL 2 in vitro by using anti-IL 2 receptor monoclonal antibodies as specific inhibitors of IL 2 function. The generation of allogeneic cytotoxic T lymphocyte (CTL) responses and maximal thymocyte proliferation to phytohemagglutinin (PHA) and IL 1 was readily susceptible to inhibition by these antibodies. Furthermore, the IL 2 receptor-positive, IL 2-responsive cell in the CTL cultures expressed killer cell activity. A greater variability in susceptibility to anti-IL 2 receptor antibody inhibition was noted for proliferation of T cells to concanavalin A, PHA, or allogeneic cells. Under certain conditions, however, each of these responses was almost completely inhibited. In most instances, the failure to block a response could be accounted for by either high levels of endogenous IL 2 production or high density of cell surface IL 2 receptors, which represent two known variables that influence the level of inhibition by these antibodies. Analysis of IL 2 receptor expression by mitogen-stimulated T cells suggested that accessory cells may play a role in the optimal expression of the IL 2 receptor. These experiments demonstrate that IL 2 is the predominant growth factor by which T lymphocytes proliferate, but do not exclude the possibility of an IL 2-independent pathway for growth.
Collapse
|
523
|
Malek TR, Ortega G, Jakway JP, Chan C, Shevach EM. The murine IL 2 receptor. II. Monoclonal anti-IL 2 receptor antibodies as specific inhibitors of T cell function in vitro. THE JOURNAL OF IMMUNOLOGY 1984. [DOI: 10.4049/jimmunol.133.4.1976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We assessed the dependency of a variety of immune responses for IL 2 in vitro by using anti-IL 2 receptor monoclonal antibodies as specific inhibitors of IL 2 function. The generation of allogeneic cytotoxic T lymphocyte (CTL) responses and maximal thymocyte proliferation to phytohemagglutinin (PHA) and IL 1 was readily susceptible to inhibition by these antibodies. Furthermore, the IL 2 receptor-positive, IL 2-responsive cell in the CTL cultures expressed killer cell activity. A greater variability in susceptibility to anti-IL 2 receptor antibody inhibition was noted for proliferation of T cells to concanavalin A, PHA, or allogeneic cells. Under certain conditions, however, each of these responses was almost completely inhibited. In most instances, the failure to block a response could be accounted for by either high levels of endogenous IL 2 production or high density of cell surface IL 2 receptors, which represent two known variables that influence the level of inhibition by these antibodies. Analysis of IL 2 receptor expression by mitogen-stimulated T cells suggested that accessory cells may play a role in the optimal expression of the IL 2 receptor. These experiments demonstrate that IL 2 is the predominant growth factor by which T lymphocytes proliferate, but do not exclude the possibility of an IL 2-independent pathway for growth.
Collapse
|
524
|
Freese AM, Chan C. [Optimal preparation procedures for repositioning splints]. DAS DENTAL-LABOR. LE LABORATOIRE DENTAIRE. THE DENTAL LABORATORY 1984; 32:1163-5. [PMID: 6596225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
525
|
Chan C, Juzwishin DW. Patient surveys--an administrative tool. HEALTH CARE 1984; 26:22-3. [PMID: 10267367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
|
526
|
Austin SJ, Chan C. Oxygen as a driving gas for nebulisers: safe or dangerous? BRITISH MEDICAL JOURNAL 1984; 288:488. [PMID: 6419982 PMCID: PMC1444730 DOI: 10.1136/bmj.288.6415.488-c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
527
|
Roizman B, Norrild B, Chan C, Pereira L. Identification and preliminary mapping with monoclonal antibodies of a herpes simplex virus 2 glycoprotein lacking a known type 1 counterpart. Virology 1984; 133:242-7. [PMID: 6199891 DOI: 10.1016/0042-6822(84)90447-1] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The properties of herpes simplex virus 2 (HSV-2)-specific proteins reactive with monoclonal antibody H966 derived from mice immunized with HSV-2 strain G are reported. The reactive proteins contained in infected cell lysates subjected to electrophoresis in denaturing gels and transferred to nitrocellulose sheets form a relatively sharp band characteristic of Mr 124,000 proteins and a diffuse, more slowly migrating band. Antigens reactive with H966 were detected on the surface of viable, unfixed cells. The electrophoretic mobility of the H966-reactive proteins made in the presence of tunicamycin was more rapid than that of the proteins made in the absence of the drug. Direct evidence that the HSV-2-specific antigen was a glycoprotein emerged from purification of [14C]glucosamine-labeled proteins with similar electrophoretic mobilities by immunoabsorption to H966 bound to Sepharose beads. Analyses of the reactivity of HSV-1 X HSV-2 recombinants indicated the gene specifying the glycoprotein maps in the S component of the DNA. The glycoprotein detected by H966 has no known counterpart in HSV-1 and corresponds to the glycoprotein previously designated as gC of HSV-2 and reported to map to the right of gC specified by HSV-1. Inasmuch as an HSV-2 gene colinear with HSV-1 gC has been reported to specify a glycoprotein currently designated as gC of HSV-2 by Para et al. [J. Virol. 45, 1223-1227 (1983)], the glycoprotein identified by H966 should be designated as gG.
Collapse
|
528
|
Chan C, Tsang H. Inhibition of flexion reflex by transcutaneous electrical nerve stimulation (Tens) in man. Pain 1984. [DOI: 10.1016/0304-3959(84)90228-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
529
|
Glimcher LH, Schroer JA, Chan C, Shevach EM. Fine specificity of cloned insulin-specific T cell hybridomas: evidence supporting a role for tertiary conformation. THE JOURNAL OF IMMUNOLOGY 1983. [DOI: 10.4049/jimmunol.131.6.2868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Two groups of cloned insulin-specific T cell hybridomas were derived from the fusion of (BALB/c X A/J)F1 T cells with the BW5147 tumor line. Group I responded only to the immunogen pork insulin and failed to respond to rat insulin, which differs only at amino acids A4 and B3. The second group of T cell hybridomas exhibited a broader pattern of reactivity to heterologous insulins because they could be stimulated with the B chain-identical pork, beef, sheep, and human insulins, as well as by isolated oxidized B chain. These hybridomas, however, displayed a much greater reactivity to pork insulin than to beef insulin or to the oxidized B chain. Comparison of the reactivity profiles of these two groups of hybridomas with the three-dimensional structure of the insulin molecule strongly suggested that group I cells were recognizing an immunogenic moiety composed of residues A4 and/or B3 in association with A chain loop determinants and that group II hybrids recognized a moiety composed of the amino acid sequence of the B chain and the A chain loop. Both groups of hybrids were restricted to the high-responder I-Ad allele but could be distinguished by their pattern of alloreactivity. We were unable to show any effect of a panel of monoclonal anti-insulin antibodies on the induction of interleukin 2 secretion by these hybridomas or to demonstrate the presence of idiotypic determinants on these T hybrids by using a panel of anti-idiotypic reagents raised against the monoclonal anti-insulin antibodies.
Collapse
|
530
|
Glimcher LH, Schroer JA, Chan C, Shevach EM. Fine specificity of cloned insulin-specific T cell hybridomas: evidence supporting a role for tertiary conformation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1983; 131:2868-74. [PMID: 6196405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Two groups of cloned insulin-specific T cell hybridomas were derived from the fusion of (BALB/c X A/J)F1 T cells with the BW5147 tumor line. Group I responded only to the immunogen pork insulin and failed to respond to rat insulin, which differs only at amino acids A4 and B3. The second group of T cell hybridomas exhibited a broader pattern of reactivity to heterologous insulins because they could be stimulated with the B chain-identical pork, beef, sheep, and human insulins, as well as by isolated oxidized B chain. These hybridomas, however, displayed a much greater reactivity to pork insulin than to beef insulin or to the oxidized B chain. Comparison of the reactivity profiles of these two groups of hybridomas with the three-dimensional structure of the insulin molecule strongly suggested that group I cells were recognizing an immunogenic moiety composed of residues A4 and/or B3 in association with A chain loop determinants and that group II hybrids recognized a moiety composed of the amino acid sequence of the B chain and the A chain loop. Both groups of hybrids were restricted to the high-responder I-Ad allele but could be distinguished by their pattern of alloreactivity. We were unable to show any effect of a panel of monoclonal anti-insulin antibodies on the induction of interleukin 2 secretion by these hybridomas or to demonstrate the presence of idiotypic determinants on these T hybrids by using a panel of anti-idiotypic reagents raised against the monoclonal anti-insulin antibodies.
Collapse
|
531
|
Presant CA, Multhauf P, Klein L, Chan C, Chang FF, Hum G, Joseph R, Opfell R, Lemkin S, Shiftan T, Plotkin D. Thymidine and 5-FU: a Phase II pilot study in colorectal and breast carcinomas. CANCER TREATMENT REPORTS 1983; 67:735-6. [PMID: 6871891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
532
|
Chan C, Huffaker G. Herpes zoster ophthalmicus with contralateral hemiparesis. A case report and review of the literature. JOURNAL OF CLINICAL NEURO-OPHTHALMOLOGY 1983; 3:111-4. [PMID: 6224810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
An 80-year-old man developed right herpes zoster ophthalmicus complicated by contralateral hemiparesis after right cataract extraction. Although herpes zoster ophthalmicus is a frequent occurrence among the elderly, the association with contralateral hemiparesis is probably overlooked by many ophthalmologists. A review of the literature has been made to outline the etiology of this problem and to make diagnosis more likely. The varicella virus probably spreads in a retrograde fashion from the gasserian ganglion toward the cavernous sinus to involve cranial nerves 3, 4, or 6. Involvement of the ipsilateral carotid arterial system by the progressive inflammatory reaction can result in the contralateral hemiparesis. Standard therapy includes topical steroids and topical antibiotics for the ocular and surface lesions. The efficacy of systemic steroids to minimize the hemiparesis is still in question.
Collapse
|
533
|
Roberts E, Ahluwalia MB, Lee G, Chan C, Sarma DS, Farber E. Resistance to hepatotoxins acquired by hepatocytes during liver regeneration. Cancer Res 1983; 43:28-34. [PMID: 6401166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The appearance of resistance to a number of hepatotoxins in primary cultures of hepatocytes prepared at various time intervals up to 2 weeks after partial hepatectomy is the major focus in this study. Resistance to the cytocidal effect of aflatoxin B1, 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, methotrexate, or methyl methanesulfonate shows a progressive increase until 48 hr and then returns to the resting level of susceptibility by 2 weeks. The genesis of mutagens from 2-acetylaminofluorene and aflatoxin B1 by S-9 liver fractions shows a decrease from and return to control values after partial hepatectomy that parallels the resistance. The levels of total cellular cytochromes P-450 also decrease following partial hepatectomy and remain from 28 to 36% less than those of controls for at least 1 week. The glutathione and total soluble sulfhydryl ("glutathione") content increase following partial hepatectomy, and the pattern is consistent with a partial role for glutathione in the resistance phenomenon as it relates to 2-acetylaminofluorene. The possible relationship between resistance to the cytocidal effects in vitro and the resistance to inhibition of cell proliferation in vivo during liver carcinogenesis is discussed.
Collapse
|
534
|
Presant CA, Ardalan B, Multhauf P, Chan C, Staples R, Green L, Browning S, Carr BI, Chang FF, Thayer W. Continuous five-day infusion of PALA and 5FU: a pilot phase II trial. MEDICAL AND PEDIATRIC ONCOLOGY 1983; 11:162-3. [PMID: 6222250 DOI: 10.1002/mpo.2950110305] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In order to determine whether a simultaneous infusion of N-(phospho-n-acetyl)-L-aspartic acid (PALA) was able to increase the rate of antitumor response to 5-fluorouracil (5-FU), a pilot study was conducted. Of 10 evaluable patients with previously drug-untreated colorectal carcinoma, there were only two partial responses, lasting 2.3 and 1.6 months. No partial responses were observed in three evaluable patients with soft tissue sarcomas. The dose-limiting toxicity was dermatitis. The simultaneous infusion of PALA and 5-FU is not likely to produce a high number of antitumor responses of long duration in patients with colorectal carcinoma.
Collapse
|
535
|
Shevach EM, Chan C, Clement LT. Nature of the antigenic complex recognized by T lymphocytes. VIII. Specific inhibition of the stimulatory capacity of antigen-pulsed hapten-modified peritoneal exudate cells by anti-hapten antibody. Eur J Immunol 1982; 12:819-24. [PMID: 6184235 DOI: 10.1002/eji.1830121005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
When macrophages which were pulsed with soluble protein antigens and then modified with 2,4,6-trinitrobenzenesulfonic acid (TNBS) were cultured with primed T cells in the presence of anti-2,4,6-trinitrophenyl (TNP) antiserum, a marked inhibition of the T cell proliferative response specific for the soluble protein antigen under study was observed. Inhibition of the proliferative response required that the protein antigen under study be easily susceptible to conjugation with TNBS. A lag period of 1-3 h must elapse following pulse exposure to the protein antigen and prior to TNP modification for anti-TNP antibody to exert an inhibitory effect, which suggests that processing of antigen in an intracellular site might occur with subsequent reexpression of antigen on the macrophage surface. It was hypothesized that anti-TNP antibody inhibits T cell proliferation by capping and shedding of TNP-modified determinants of the nominal antigen as well as TNP-modified cell surface proteins from the macrophage membrane. The failure of others to demonstrate an effect of anti-antigen antibody on T cell activation can best be explained as secondary to the low density of antigenic determinants on the macrophage membrane with resultant low-affinity binding of antibody to antigen.
Collapse
|
536
|
Johnson SM, Chan C, Cheng S, Shimek JL, Nygard G, Khalil SK. Isocratic high-performance liquid chromatographic method for the determination of tricyclic antidepressants and metabolites in plasma. J Pharm Sci 1982; 71:1027-30. [PMID: 7131268 DOI: 10.1002/jps.2600710918] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
An isocratic high-performance liquid chromatographic method for the determination of six tricyclic antidepressants and their major metabolites is presented. Hexane containing 0.5% diethylamine was used as an extraction solvent to minimize adsorption onto glass. A reversed-phase cyanopropylsilane column was used with a mobile phase consisting of 70% acetonitrile and 30% 0.03 M acetate buffer, pH 7.0. Good identification and quantitation were obtained by the use of both UV detection at 245 nm and spectrofluorometric detection with an excitation wavelength of 276 nm and an emission filter with a 370-nm cutoff. A minimum detectable limit of less than 5 ng/ml of plasma is possible with this system. The reproducibility and precision of the method are shown from the analysis of samples containing 20-400 ng/ml in plasma.
Collapse
|
537
|
Shevach EM, Chan C, Bitter-Suermann H. Induction of transplantation tolerance in guinea pigs by spleen allografts. II. Responses in the mixed leukocyte reaction correlate with the tolerant state. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1982; 129:710-5. [PMID: 6211492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We have developed a model for the induction of transplantation tolerance in the guinea pig by vascularized spleen allografts. Spleen allografts from strain 13 to strain 2 hosts frequently survived in healthy recipients without clinical GVHD or induced clinical GVHD. (2 x 13)F1 to strain 2 spleen allografts survived indefinitely without inducing GVHD. In contrast, strain 2 spleen allografts were rejected by strain 13 hosts. An excellent correlation was observed between the clinical course and the degree of reactivity to donor strain stimulator cells in the MLR. Animals that had rejected their grafts had normal or enhanced proliferative responses in the MLR. Strain 2 hosts with long-term surviving strain 13 or (2 x 13)F1 grafts had markedly suppressed anti-13 responses. Animals with GVHD had a suppressed MLR toward donor strain stimulator cells with simultaneous reactivity to host strain stimulator cells. Cells capable of suppressing the response of normal host strain cells to donor strain stimulators were present in some long-term surviving animals and may be responsible in part for the maintenance of the tolerant state.
Collapse
|
538
|
Shevach EM, Chan C, Bitter-Suermann H. Induction of transplantation tolerance in guinea pigs by spleen allografts. II. Responses in the mixed leukocyte reaction correlate with the tolerant state. THE JOURNAL OF IMMUNOLOGY 1982. [DOI: 10.4049/jimmunol.129.2.710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
We have developed a model for the induction of transplantation tolerance in the guinea pig by vascularized spleen allografts. Spleen allografts from strain 13 to strain 2 hosts frequently survived in healthy recipients without clinical GVHD or induced clinical GVHD. (2 x 13)F1 to strain 2 spleen allografts survived indefinitely without inducing GVHD. In contrast, strain 2 spleen allografts were rejected by strain 13 hosts. An excellent correlation was observed between the clinical course and the degree of reactivity to donor strain stimulator cells in the MLR. Animals that had rejected their grafts had normal or enhanced proliferative responses in the MLR. Strain 2 hosts with long-term surviving strain 13 or (2 x 13)F1 grafts had markedly suppressed anti-13 responses. Animals with GVHD had a suppressed MLR toward donor strain stimulator cells with simultaneous reactivity to host strain stimulator cells. Cells capable of suppressing the response of normal host strain cells to donor strain stimulators were present in some long-term surviving animals and may be responsible in part for the maintenance of the tolerant state.
Collapse
|
539
|
Morton BE, Martin C, Chan C, Olipares H. Inexpensive fiber optic two-dimensional densitometer for the high-resolution quantitation of autoradiogram grain densities. J Neurosci Methods 1982; 6:113-9. [PMID: 7121055 DOI: 10.1016/0165-0270(82)90021-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The design and construction of a simple, low cost high performance fiber optic 2-dimensional microdensitometer is described. With this instrument the film to be quantitated is placed upon a back-lit frosted glass bench and scanned with an optic fiber probe attached to a transparent micromanipulator. The emerging light is transported by the fiber to the photocell of a direct reading spectrophotometer. The resulting numerical data can either be transcribed, portrayed on a recorder or entered into the memory of a microdata processor for further analysis and comparisons. The instrument was sensitive to very small differences in optical density and could resolve lines 100 but not 30 micrometers apart. It was precise, reliable and easy to build. With the use of this equipment many previously undetected, significant local brain glucose utilization differences were quantitated in groups of unrestrained rodents, maintained in several behavioral states.
Collapse
|
540
|
Chan C. Rock analysis. Trends Analyt Chem 1982. [DOI: 10.1016/0165-9936(92)80015-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
541
|
Thibault P, Liu Y, Chan C, Lee J, Knystautas R, Guirao C, Hjertager B, Fuhre K. Transmission of an explosion through an orifice. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/s0082-0784(82)80234-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
542
|
Bertram DA, Schumacher DN, Horn SD, Clopton CJ, Lord JG, Chan C. Hospital case mix groupings and generic algorithms. QRB. QUALITY REVIEW BULLETIN 1982; 8:24-30. [PMID: 6803207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
543
|
Chan C, Evans JW, Hoffman DK. Factorization relations and consistency conditions in the sudden approximation. J Chem Phys 1981. [DOI: 10.1063/1.442113] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
544
|
Schumacher DN, Chan C. Medical staff and hospital administration uses of discharge abstract data. QRB. QUALITY REVIEW BULLETIN 1981; 7:26-35. [PMID: 6789279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In summary, this article suggests several useful approaches whereby physicians and hospital administrators can efficiently sort through large amounts of discharge abstract data to identify problem areas, particularly those concerning quality of care and utilization of services, and to formulate strategies for improvement. Approaches and steps suggested include: . Review objectives-determining variables of greatest concern; . Standards-determining acceptable values or levels of performance; . Focus of review-determining the unit of review, such as specific departments, diseases, or physicians; and . Quality and reliability of discharge abstract data-determining the data to use by undertaking four levels of edits: technical edits, logical edits, ratio edits, and categorical edits. A model flowchart provided in this article serves as a conceptual framework by which potential problem areas can be studied during a patient's hospitalization to precisely identify the interaction, the time, and the cause/association of the problem.
Collapse
|
545
|
|
546
|
Chan C, Daily JW. Measurement of temperature in flames using laser induced fluorescence spectroscopy of OH. APPLIED OPTICS 1980; 19:1963-1968. [PMID: 20221163 DOI: 10.1364/ao.19.001963] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A technique for measuring translational flame temperature utilizing the laser induced fluorescence spectrum of OH is demonstrated. The method is based on matching the observed spectrum to a numerical model in which the detailed balance temperature is a parameter. The precision of the method exceeds that of the line reversal technique. Accuracy is limited by the calibration source and the validity of the numerical rotational relaxation rate model.
Collapse
|
547
|
Abstract
The response of OH in flames to laser excitation is studied in some detail. The population balance equations are solved numerically using an empirical model for the rotational relaxation rates. The empirical model parameters are fit to experimental spectra using a linear regression procedure and the resulting description of OH behavior is shown to be satisfactory to within the precision of the data. The model is then used to recover branching ratios for a number of flame conditions.
Collapse
|
548
|
Abstract
The large body of research demonstrating the effectiveness of antipsychotic drugs in the treatment of acute schizophrenia is selectively reviewed. Research evidence relevant to the following issues is assessed; indications for selective treatment; characteristics of drug responders and nonresponders; indications for high dosage phenothiazine treatment; indications for maintenance therapy; benefits and risks of antipsychotic drugs. Recommendations are made concerning areas of psychopharmacologic research that require further development.
Collapse
|
549
|
|
550
|
Chan C, Yamamoto K, Konishi S, Ogata M. Isolation and antigenic characterization of Haemophilus parahaemolyticus from porcine pneumonia. NIHON JUIGAKU ZASSHI. THE JAPANESE JOURNAL OF VETERINARY SCIENCE 1978; 40:103-7. [PMID: 642222 DOI: 10.1292/jvms1939.40.103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|