451
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Kim E, Hong S, Kim KS, Jiang ZT, Kim DW, Lim S, Woo SG, Koh YB, No K. Simulation and fabrication of attenuated phase-shifting masks: CrF(x). Appl Opt 1997; 36:7247-7256. [PMID: 18264234 DOI: 10.1364/ao.36.007247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
To acquire the required resolution for 248- and 193-nm lithography, a study of attenuated phase-shifting mask (Att-PSM) technology is in progress. We performed a simulation study using a matrix method to calculate relative transmittance and the amount of phase shift of light through the PSM. However, we found that the average film composition changed with deposition time. Accordingly, optical constants were found to be a strong function of film thickness. Therefore we rearranged the relationship between deposition parameters (e.g., deposition time or gas flow rate ratio) and optical constants (e.g., refractive index and extinction coefficient) to extract the empirical formula for the optical constants with respect to film composition. To verify our simulation study, we fabricated a phase shifter based on our simulation result, which was found to have a transmittance of 8.3% and a phase shift of 179.5 degrees . Consequently, we obtained a reliable optimum condition for the deep-ultraviolet Att-PSM.
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452
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Suzuki Y, Rani S, Liesenfeld O, Kojima T, Lim S, Nguyen TA, Dalrymple SA, Murray R, Remington JS. Impaired resistance to the development of toxoplasmic encephalitis in interleukin-6-deficient mice. Infect Immun 1997; 65:2339-45. [PMID: 9169772 PMCID: PMC175324 DOI: 10.1128/iai.65.6.2339-2345.1997] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The role of interleukin-6 (IL-6) in the pathogenesis of toxoplasmic encephalitis (TE) was examined by using IL-6-targeted mutant (IL-6(-/-)) mice. At 4 and 8 weeks after infection with the ME49 strain of Toxoplasma gondii, significantly greater numbers of T. gondii cysts and areas of inflammation associated with tachyzoites were observed in brains of IL-6(-/-) mice than in those of control mice. Large areas of necrosis were observed only in brains of IL-6(-/-) mice. Tachyzoites were frequently detected in the areas of necrosis, suggesting that necrosis was caused by proliferation of the parasite. These results indicate that IL-6 is protective against development of TE by preventing formation of T. gondii cysts and proliferation of tachyzoites in brains of infected mice. Whereas in brains of control mice, large numbers of inflammatory cells were always observed in areas where tachyzoites were detected, in brains of IL-6(-/-) mice, only small numbers of inflammatory cells were observed in many areas with tachyzoites. Lymphocyte preparations isolated from brains of infected control mice had significantly higher ratios of gamma/delta T cells and CD4+ alpha/beta T cells but lower ratios of CD8+ alpha/beta T cells compared to those of infected IL-6(-/-) mice. There were no differences in the ratios of these T-cell subsets in spleens between these mice. The amounts of mRNA for gamma interferon (IFN-gamma) detected by reverse transcriptase PCR were significantly smaller in brains of IL-6(-/-) mice than in those of control mice, whereas amounts of IL-10 mRNA were greater in the former than in the latter. IL-6 mRNA was detected only in infected control mice. The protective activity of IL-6 against development of TE appears to be through its ability to stimulate IFN-gamma production and induce infiltration and accumulation of different T-cell subsets in brains of infected mice.
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Affiliation(s)
- Y Suzuki
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, California 94301, USA.
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453
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Lee HC, Song YD, Li HR, Park JO, Suh HC, Lee E, Lim S, Kim K, Huh K. Mitochondrial gene transfer ribonucleic acid (tRNA)Leu(UUR) 3243 and tRNA(Lys) 8344 mutations and diabetes mellitus in Korea. J Clin Endocrinol Metab 1997; 82:372-4. [PMID: 9024220 DOI: 10.1210/jcem.82.2.3747] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The high prevalence of diabetic patients with a mutation in the mitochondrial gene (the 3243 and 8344 bp mutations) has been identified in Japan. To determine the prevalence of diabetic patients with those mutations in Korea, we randomly screened selected 503 clinical diabetic patients regardless of their diabetes types. We found only 1 patient with the mitochondrial DNA mutation at position 3243 (percent mutation, 32%), and the mitochondrial DNA mutation at position 8344 was not found in any of the patients. The affected subject was a 22-yr-old man with a history of myoclonic epilepsy and mild sensorineural hearing loss, a 1-yr duration of diabetes mellitus, and a low level C peptide response to oral glucose. Because of the low frequency of these mutations in the Korean diabetic population, we concluded that these particular mutations of mitochondrial DNA may not be a common contributor to diabetes mellitus in Korea.
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Affiliation(s)
- H C Lee
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
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454
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Shawis T, Bacon M, Lim S. Are We Screening Properly for Disabling Diabetic Complications in the Very Elderly? Age Ageing 1997. [DOI: 10.1093/ageing/26.suppl_3.p32-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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455
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Sharma P, Lim S, James D, Orchard RT, Horne M, Seymour CA. Pancreatitis may occur with a normal amylase concentration in hypertriglyceridaemia. BMJ 1996; 313:1265. [PMID: 8939147 PMCID: PMC2352581 DOI: 10.1136/bmj.313.7067.1265] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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456
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Suzuki Y, Yang Q, Yang S, Nguyen N, Lim S, Liesenfeld O, Kojima T, Remington JS. IL-4 is protective against development of toxoplasmic encephalitis. J Immunol 1996; 157:2564-9. [PMID: 8805658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
IFN-gamma is critical for prevention of development of toxoplasmic encephalitis (TE). Since IL-4 down-regulates production of IFN-gamma, we examined its role in the pathogenesis of TE in IL-4-targeted mutant (IL-4-/-) mice. IL-4-/- mice all died from 6 to 20 wk after peroral infection with cysts of the ME49 strain of Toxoplasma gondii; control mice survived. At 4 and 8 wk after infection, significantly greater numbers of T. gondii cysts and foci of acute inflammation, and greater amounts of tachyzoite-specific mRNA (by reverse-transcriptase PCR) were in brains of IL-4-/- mice than controls. Toxoplasma IgG2b and IgG3 Ab levels were slightly but significantly higher in sera of IL-4-/- than control mice, whereas IgM and IgG2a levels did not differ between these mice. Toxoplasma IgG1 and IgE Abs were not detected in sera of either strain. Amounts of IFN-gamma, TNF-alpha, IL-6, and IL-10 mRNA detected by reverse-transcriptase PCR did not differ between brains of infected IL-4-/- and controls, although brains of the former mice had greater numbers of inflammatory mononuclear cell infiltrates. IL-4 mRNA was detected only in infected control mice. Spleen cells of control mice at 8 wk after infection produced significantly greater amounts of IFN-gamma following stimulation in vitro with soluble T. gondii Ags than did those from IL-4-/- mice. These results indicate that IL-4 is protective against development of TE by preventing formation of T. gondii cysts and proliferation of tachyzoites in the brain. The impaired ability of IL-4-/- mice in the late stage of T. gondii infection to produce IFN-gamma most likely contributes to their susceptibility for development of severe TE.
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Affiliation(s)
- Y Suzuki
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
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457
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Suzuki Y, Yang Q, Yang S, Nguyen N, Lim S, Liesenfeld O, Kojima T, Remington JS. IL-4 is protective against development of toxoplasmic encephalitis. The Journal of Immunology 1996. [DOI: 10.4049/jimmunol.157.6.2564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
IFN-gamma is critical for prevention of development of toxoplasmic encephalitis (TE). Since IL-4 down-regulates production of IFN-gamma, we examined its role in the pathogenesis of TE in IL-4-targeted mutant (IL-4-/-) mice. IL-4-/- mice all died from 6 to 20 wk after peroral infection with cysts of the ME49 strain of Toxoplasma gondii; control mice survived. At 4 and 8 wk after infection, significantly greater numbers of T. gondii cysts and foci of acute inflammation, and greater amounts of tachyzoite-specific mRNA (by reverse-transcriptase PCR) were in brains of IL-4-/- mice than controls. Toxoplasma IgG2b and IgG3 Ab levels were slightly but significantly higher in sera of IL-4-/- than control mice, whereas IgM and IgG2a levels did not differ between these mice. Toxoplasma IgG1 and IgE Abs were not detected in sera of either strain. Amounts of IFN-gamma, TNF-alpha, IL-6, and IL-10 mRNA detected by reverse-transcriptase PCR did not differ between brains of infected IL-4-/- and controls, although brains of the former mice had greater numbers of inflammatory mononuclear cell infiltrates. IL-4 mRNA was detected only in infected control mice. Spleen cells of control mice at 8 wk after infection produced significantly greater amounts of IFN-gamma following stimulation in vitro with soluble T. gondii Ags than did those from IL-4-/- mice. These results indicate that IL-4 is protective against development of TE by preventing formation of T. gondii cysts and proliferation of tachyzoites in the brain. The impaired ability of IL-4-/- mice in the late stage of T. gondii infection to produce IFN-gamma most likely contributes to their susceptibility for development of severe TE.
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Affiliation(s)
- Y Suzuki
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - Q Yang
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - S Yang
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - N Nguyen
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - S Lim
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - O Liesenfeld
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - T Kojima
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
| | - J S Remington
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, CA 94301
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458
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Steinhoff BJ, So NK, Lim S, Lüders HO. Ictal scalp EEG in temporal lobe epilepsy with unitemporal versus bitemporal interictal epileptiform discharges. Neurology 1995; 45:889-96. [PMID: 7746402 DOI: 10.1212/wnl.45.5.889] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We investigated the ictal scalp EEG in 228 seizures of 36 patients with unitemporal (n = 25) or bitemporal independent (n = 11) interictal epileptiform discharges (IED). All patients had proven temporal lobe epilepsy since they became seizure-free or only had auras after temporal lobectomy with a minimum follow-up of 1 year. Ictal patterns at seizure onset or later in the course of the seizure were lateralized significantly more often in patients with unitemporal IED (90%, at seizure onset and 96%, later) compared with those with bitemporal independent IED (75%, at seizure onset and 78%, later). Furthermore, scalp ictal EEGs, when lateralized at seizure onset or later in the course of the seizure, were significantly more likely to predict the correct side for surgery in patients with unitemporal (98%, at seizure onset and 100%, later) than bitemporal (64%, at seizure onset and 77%, later) IED. Bilateral independent seizure onsets, asynchrony of ictal activity over the two temporal lobes, and switch of ictal activity from one to the other hemisphere are ictal patterns that are strongly correlated with bitemporal excitability.
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Affiliation(s)
- B J Steinhoff
- Department of Neurology, Cleveland Clinic Foundation, OH, USA
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459
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Boughton BJ, Jackson N, Lim S, Smith N. Randomized trial of intravenous immunoglobulin prophylaxis for patients with chronic lymphocytic leukaemia and secondary hypogammaglobulinaemia. Clin Lab Haematol 1995; 17:75-80. [PMID: 7621634 DOI: 10.1111/j.1365-2257.1995.tb00322.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Forty-two patients with chronic lymphocytic leukaemia (CLL), serum IgG levels < 5.5 milligrams and a history of two or more recent infections, were randomized to receive infusions of 18 g human intravenous immunoglobulin (IVIg) or human albumin placebo every three weeks. During the 12 month study 122 infections were documented but only four were associated with neutropenia. Ten patients (24%) with IgG levels < 3.0 milligrams experienced 65% of the infections. In response to IVIg there were immediate and accumulative increases in serum IgG levels and an associated decrease in total and serious infections. If three further infections occurred, placebo patients were commenced on 18 g IVIg, and IVIg patients were increased to 24 g IVIg. Approximately 50% of these cases subsequently remained infection free. The study shows the usefulness of prophylactic Sandoglobulin in CLL patients with hypogammaglobulinaemia, and suggests that this may be justified in those with recurrent infections and serum IgG levels < 3 milligrams.
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Affiliation(s)
- B J Boughton
- Department of Haematology, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
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460
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Coxson PG, Brennan KM, Huesman RH, Lim S, Budinger TF. Variability and reproducibility of rubidium-82 kinetic parameters in the myocardium of the anesthetized canine. J Nucl Med 1995; 36:287-96. [PMID: 7830133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
UNLABELLED Kinetic analysis of 82Rb dynamic PET data produces quantitative measures which could be used to evaluate ischemic heart disease. These measures have the potential to generate objective comparisons of different patients or the same patient at different times. To achieve this potential, it is essential to determine the variability and reproducibility of the kinetic parameters. METHODS A total of 48 82Rb dynamic PET datasets were acquired from two pure bred beagles. Each animal underwent eight 82Rb PET studies with essentially the same protocol for three successive weeks. Data were acquired with the Donner 600-Crystal Positron Tomograph (PET600). In each week, single-slice dynamic 82Rb PET datasets were collected with the animal at rest at three different gantry positions separated by 5 mm. Additional dataset were collected after dipyridamole infusion and after administration of aminophylline to induce a return to rest. A two-compartment kinetic model with correction for myocardial vasculature and spillover from the left ventricular blood pool was used to analyze the dynamic datasets. Model parameters for uptake (k1), washout (k2) and vascular fraction (fv) were estimated in 11-14 myocardial regions of interest (ROIs) using a weighted least-squares criterion. Statistical fluctuation due to the PET acquisition process was minimized by using a relatively high 82Rb dose (about 30 mCi) to take advantage of the high count rate capacity of the PET600. RESULTS The variation in mean k1, where the mean is taken over the myocardial ROIs was 10%-20% (Dog 1) and 15%-50% (Dog 2) among the rest studies conducted on the same date. Similar variation was evident in comparing studies in the same animal for different weeks. CONCLUSION Spatial and temporal variation in estimates of the uptake rate (k1) of 82Rb in the resting myocardium of the anesthetized canine are small in relation to the functional increase in k1 following dipyridamole infusion.
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Affiliation(s)
- P G Coxson
- Center for Functional Imaging, Lawrence Berkeley Laboratory, University of California, Berkeley 94720
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461
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Lin HJ, Kakkis ED, Sun NC, Lim S, Gurevitch AW. Acute lymphocytic leukemia in acrodermatitis enteropathica. Am J Hematol 1994; 46:374-5. [PMID: 8037198 DOI: 10.1002/ajh.2830460426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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462
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Xiong M, Pallas SL, Lim S, Finlay BL. Regulation of retinal ganglion cell axon arbor size by target availability: mechanisms of compression and expansion of the retinotectal projection. J Comp Neurol 1994; 344:581-97. [PMID: 7929893 DOI: 10.1002/cne.903440407] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The ability of pre- and postsynaptic populations to achieve the proper convergence ratios during development is especially critical in topographically mapped systems such as the retinotectal system. The ratio of retinal ganglion cells to their target cells in the optic tectum can be altered experimentally either by early partial tectal ablation, which results in an orderly compression of near-normal numbers of retinal projections into a smaller tectal area, or by early monocular enucleation, which results in the expansion of a reduced number of axons in a near-normal tectal volume. Our previous studies showed that changes in cell death and synaptic density consequent to these manipulations can account for only a minor component of this compensation for the population mismatch. In this study, we examine other mechanisms of population matching in the hamster retinotectal system. We used an in vitro horseradish peroxidase labeling method to trace individual retinal ganglion cell axons in superior colliculi partially ablated on the day of birth, as well as in colliculi contralateral to a monocular enucleation. We found that individual axon arbors within the partially lesioned tectum occupy a smaller area, with fewer branches and fewer terminal boutons, but preserve a normal bouton density. In contrast, ipsilaterally projecting axon arbors in monocularly enucleated animals occupy a greater area than in the normal condition, with a much larger arbor length and greater number of boutons and branches compared with normal ipsilaterally projecting cells. Alteration of axonal arborization of retinal ganglion cells is the main factor responsible for matching the retinal and tectal cell populations within the tectum. This process conserves normal electrophysiological function over a wide range of convergence ratios and may occur through strict selectivity of tectal cells for their normal number of inputs.
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Affiliation(s)
- M Xiong
- Department of Psychology, Cornell University, Ithaca, New York 14853
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463
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464
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Lim S, White JL. Polymer crystalline orientation resulting from melt deformation and solidification of talc and mica filled polyethylene compounds. Colloid Polym Sci 1993. [DOI: 10.1007/bf00660089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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465
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Preston SH, Lim S, Morgan SP. African-American marriage in 1910: beneath the surface of census data. Demography 1992; 29:1-15. [PMID: 1547897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This paper examines the quality of information about marital status, marital duration, and marriage order among African-American women in the U.S. Census of 1910. It compares the reported prevalence of widowhood to estimates of widowhood based on the mortality of black men and on the ages of women at first marriage. It also compares the reported distributions of duration of first marriage to estimates based on mortality and on age at first marriage. It concludes that census reports are subject to serious error. Widowhood is overreported, and marital turnover appears to have been faster than implied by census reports. The prevalance of "own children" is used to confirm these conclusions and to suggest motivations for misreporting.
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Affiliation(s)
- S H Preston
- Population Studies Center, University of Pennsylvania, Philadelphia 19174
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466
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Puisieux A, Lim S, Groopman J, Ozturk M. Selective targeting of p53 gene mutational hotspots in human cancers by etiologically defined carcinogens. Cancer Res 1991; 51:6185-9. [PMID: 1933877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In lung and liver cancers, p53 mutations are mostly G:C to T:A transversions. This type of mutation is known to be induced by benzo(a)pyrene and aflatoxin B1 which are associated with the etiology of lung and liver cancers, respectively. Using a novel assay based on DNA polymerase fingerprint analysis, we identified p53 nucleotides targeted by these carcinogens. Thirteen of 14 nucleotide residues of the p53 gene which underwent G:C to T:A mutations in lung cancers were targeted by benzo(a)pyrene. Similarly, aflatoxin B1 formed adducts at a mutational hotspot specific for liver cancer. The same nucleotide (third base of codon 249), which mutates rarely in lung cancers, was not a target for benzo(a)pyrene. These in vitro observations indicate that p53 mutational hotspots identified in different tumors are selected targets specifically for the etiologically defined environmental carcinogens.
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Affiliation(s)
- A Puisieux
- Molecular Hepatology Laboratory, Massachusetts General Hospital Cancer Center, Charlestown 02129
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467
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Nwokolo CU, Prewett EJ, Sawyerr AM, Hudson M, Lim S, Pounder RE. Tolerance during 5 months of dosing with ranitidine, 150 mg nightly: a placebo-controlled, double-blind study. Gastroenterology 1991; 101:948-53. [PMID: 1889719 DOI: 10.1016/0016-5085(91)90720-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Repeated dosing with an H2-receptor antagonist results in a modest decrease in antisecretory potency termed "tolerance." The object of this prospective study was to determine whether tolerance is a progressive phenomenon or whether it levels off during prolonged dosing with a standard maintenance dose of an H2-antagonist. The effect of continuous dosing with ranitidine, 150 mg nightly, was compared with intermittent dosing (27 days of placebo each month) with active ranitidine, 150 mg nightly, only on the night of each experiment. Simultaneous 24-hour intragastric acidity and plasma gastrin concentration were measured monthly for 5 months in 17 healthy subjects (7 continuous and 10 intermittent dosing). In the intermittent-dosing group, the antisecretory response to ranitidine, 150 mg nightly, was preserved throughout the 141-day trial period; the median nocturnal integrated acidity decreased from 557 mmol.h/L (day 0) to 38 mmol.h/L on day 1 of dosing, and it ranged between 32 and 55 (median, 45) mmol.h/L during days 29-141. In the continuous-dosing group, there was a significant return of nocturnal intragastric acidity on days 29 and 85 compared with day 1 of dosing. The median nocturnal integrated acidity decreased in the continuous-dosing group from 554 mmol.h/L (day 0) to 87 mmol.h/L on the first day of dosing, and it ranged between 145 and 287 (median, 170) mmol.h/L during days 29-141. Either intermittent or continuous dosing with ranitidine was associated with an elevation of plasma gastrin concentration, which remained constant throughout the 5-month study. Tolerance does develop in healthy subjects during the first month of dosing with ranitidine, 150 mg nightly, but it is not a progressive phenomenon, and it is probably not of clinical relevance.
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Affiliation(s)
- C U Nwokolo
- University Department of Medicine, Royal Free Hospital School of Medicine, London, England
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468
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Abstract
The aim of this study was to determine the mechanisms responsible for concordant xenograft rejection using the hamster-to-rat heart graft model. Even though it was known that rat CD4 positive T cells proliferated to hamster stimulators in mixed lymphocyte reactions, the depletion of CD4 positive T cells in rat recipients did not lead to an extension of xenograft survival. Suppression of T cell immunity using other monoclonal antibodies or cyclosporine also failed to improve survival. Only by depleting complement with cobra-venom factor could hamster xenograft survival be prolonged, and long-term survival was achieved by combining CsA with COF. High-antibody titers to hamster cells were found after transplantation of hamster hearts, and evidence is presented that rejection of these "concordant" xenografts is mediated primarily by antibody-complement mechanisms. The antihamster antibodies were produced in the absence of T cell help, which suggests that antibody-mediated graft destruction cannot be inhibited by suppression or depletion of T cells. Pharmacologic depletion of complement for the clinical application of concordant xenografts is a promising avenue of future research.
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Affiliation(s)
- J van den Bogaerde
- Department of Surgery, Cambridge University Medical School, Addenbrookes Hospital, United Kingdom
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469
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Friend PJ, Waldmann H, Cobbold S, Tighe H, Rebello P, Wight D, Gore S, Pollard S, Lim S, Johnston P. The anti-IL-2 receptor monoclonal antibody YTH-906 in liver transplantation. Transplant Proc 1991; 23:1390-2. [PMID: 1989247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- P J Friend
- Department of Surgery, University of Cambridge, UK
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470
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Tomar RS, Lim S, Gill SS. The effects of epoxidized xenobiotics on mitogen responsiveness and antibody-producing ability of murine spleen cells in vitro. Int J Immunopharmacol 1991; 13:57-65. [PMID: 2026476 DOI: 10.1016/0192-0561(91)90026-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of benzo(a)pyrene [B(a)P], B(a)P-4,5- and 7,8-dihydroepoxide, (+)-B(a)P-7,8-diol, (-)-B(a)P-7,8-diol, cholestan-5 alpha,6 alpha-epoxy-3 beta-ol, cholestan-5 beta,6 beta-epoxy-3 beta-ol, cholestantriol and styrene oxide, on the in vitro mitogen responses and antibody-producing ability of mouse spleen cells were evaluated. B(a)P suppressed the plaque-forming cell (PFC) response to T-cell dependent antigen sheep red blood cells (SRBC), but had no effect on the proliferative response to mitogens (phytohemagglutinin, concanavalin A and lipopolysaccharides) except a slight but significant increase to concanavalin A at lower doses. B(a)P-4,5- and 7,8-dihydroepoxides completely inhibited the proliferative response at concentrations exceeding 10(-6) M, but lower concentrations were without any effect. These two epoxides also suppressed the PFC response at concentration greater than or equal to 10(-5) M. This was accompanied by reduced cell viability. (+)-B(a)P-7,8-diol produced a dose-dependent suppression of PFC response to SRBC without altering the cell viability. The proliferative response was inhibited only at concentration greater than or equal to 10(-4) M. In contrast, (-)-B(a)P-7,8-diol has no effect on the PFC response and suppressed the proliferative response only at concentration of greater than or equal to 10(-5) M. Cholestan compounds had no effect on the plaque-forming cell response at concentrations less than or equal to 10(-5) M. The effects on the proliferative response to mitogens were inhibitory and stimulatory depending upon the dose used. Styrene oxide neither inhibited the PFC nor the proliferative responses.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R S Tomar
- Department of Entomology, University of California, Riverside 92521-1037
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471
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Abstract
Hypercholesterolemic rabbit beta-VLDL and human LDL are both internalized by mouse peritoneal macrophages by receptor-mediated endocytosis. However, only beta-VLDL (which binds to the cells with a much higher affinity than LDL) markedly stimulates acyl-CoA/cholesterol acyl transferase (ACAT) and induces foam cell formation in these cells. As an initial step to test whether the two lipoproteins might be targeted to different organelles (which might differ in their ability to deliver cholesterol to microsomal ACAT), we studied the endocytic pathways of beta-VLDL and LDL. Lipoproteins were labeled with the non-transferable fluorescent label, DiI. When the macrophages were incubated with DiI-LDL for 10 min at 37 degrees C, the fluorescence was concentrated near the center of the cell both in heavily labeled vesicles and in a diffuse pattern. The pattern with DiI-beta-VLDL was quite different: an array of bright vesicles throughout the cytoplasm was the predominant feature. Differences in distribution were seen as early as 2 min of incubation and persisted throughout a 10-min chase period. By using a procedure in which photobleaching of DiI fluorescence converts diaminobenzidine into an electron-dense marker, we were able to identify at the ultrastructural level vesicles containing electron-dense material in cells incubated with DiI-beta-VLDL. Human E2/E2 beta-VLDL (from a patient with familial dysbetalipoproteinemia), which has a binding affinity and ACAT-stimulatory potential similar to LDL, gave a pattern of fluorescence virtually identical to LDL. Pulse-chase studies with 125I-labeled and [3H]cholesteryl ester-labeled lipoproteins disclosed that both protein degradation and cholesteryl ester hydrolysis were markedly retarded in beta-VLDL compared with LDL. Thus, in mouse peritoneal macrophages, endocytosed beta-VLDL appears in a distinct set of widely-distributed vesicles not seen with LDL (or with E2-beta-VLDL) and, compared with LDL, has a markedly diminished rate of protein degradation and cholesteryl ester hydrolysis. The differential routing of LDL and beta-VLDL may provide a mechanism for differences in ACAT-stimulatory potential between the two lipoproteins.
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Affiliation(s)
- I Tabas
- Department of Medicine, Columbia University, New York 10032
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472
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Collier DS, Calne R, Thiru S, Lim S, Pollard SG, Barron P, Da Costa M, White DJ. Rapamycin in experimental renal allografts in dogs and pigs. Transplant Proc 1990; 22:1674-5. [PMID: 2143858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- D S Collier
- Department of Surgery, University of Cambridge, Addenbrooke's Hospital, UK
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473
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Abstract
Mice that are transgenic for human beta zero-thalassemic beta-globin alleles were generated in order to study how beta zero-thalassemic mutations affect beta-globin RNA metabolism in erythroid tissues. Three thalassemic alleles were studied, each of which harbors either a frameshift or a nonsense mutation. These mutations result in the premature termination of beta-globin mRNA translation and an abnormally low level of beta-globin mRNA in the peripheral blood of thalassemic patients. Comparative studies of mice that express any of the beta zero-thalassemic transgenes with mice that express a normal human beta-globin transgene demonstrated that all three thalassemic mRNAs are metabolized in erythroid tissues abnormally. RNA blotting and S1 nuclease transcript mapping revealed for each thalassemic transgene that (i) the full-length mRNA is abnormally short-lived and (ii) in addition to full-length mRNA, three more stable yet smaller RNAs are present. These smaller RNAs are polyadenylated and lack the mRNA 5' end.
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Affiliation(s)
- S Lim
- Department of Human Genetics, Roswell Park Memorial Institute, Buffalo, NY 14263
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474
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475
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Friend PJ, Lim S, Smith M, Jamieson NV, Rolles K, O'Grady J, Williams R, Calne RY. Liver transplantation in the Cambridge/King's College Hospital series--the first 400 patients. Transplant Proc 1989; 21:2397-8. [PMID: 2652781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- P J Friend
- Department of Surgery, University of Cambridge, England
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476
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Seroogy KB, Dangaran K, Lim S, Haycock JW, Fallon JH. Ventral mesencephalic neurons containing both cholecystokinin- and tyrosine hydroxylase-like immunoreactivities project to forebrain regions. J Comp Neurol 1989; 279:397-414. [PMID: 2563737 DOI: 10.1002/cne.902790306] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The coexistence of cholecystokinin- and tyrosine hydroxylase-like immunoreactivities within neurons of the rat ventral mesencephalon was analyzed by using an indirect immunofluorescence technique for the simultaneous demonstration of two antigens in the same tissue section. A high degree of colocalization was observed in the substantia nigra pars compacta, in which 80-90% of all labeled neurons at rostral and up to 70% at intermediate levels contained both cholecystokinin and tyrosine hydroxylase. At caudal levels, the incidence of colocalization declined to approximately 30-50%. All of the immunoreactive perikarya in the substantia nigra pars lateralis were labeled with both substances. Other areas of the ventral midbrain that exhibited a moderate proportion of neurons immunoreactive for both cholecystokinin and tyrosine hydroxylase included the ventral tegmental area, interfascicular nucleus, and rostral and caudal linear nuclei. In addition, coexistence was occasionally observed within neurons of the central and ventral periaqueductal gray matter, supramammillary region, peripeduncular region, retrorubral field, and extremely rarely, within the substantia nigra pars reticulata. Cell bodies containing tyrosine hydroxylase-like immunoreactivity (indicative of dopamine) usually outnumbered those containing the peptide except in the supramammillary region and in the ventral periaqueductal gray matter, where the cholecystokinin perikarya were present in higher numbers. The double-labeling colocalization technique was combined with fluorescence retrograde tracing to determine some of the forebrain projections of these neurons. Ventral midbrain neurons containing both cholecystokinin and tyrosine hydroxylase were found to project to the caudate-putamen, nucleus-accumbens, prefrontal cortex, and amygdala. These projections originated from neurons located predominantly in the substantia nigra pars compacta and the ventral tegmental area. Thus, cholecystokinin occurs within the well-known dopaminergic nigrostriatal pathway in the rat. Overall, these results demonstrate that a significant proportion of the dopamine neurons giving rise to the ascending mesotelencephalic projections also contain the peptide cholecystokinin.
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Affiliation(s)
- K B Seroogy
- Department of Anatomy and Neurobiology, University of California, Irvine 92717
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477
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Lim S, Boughton BJ, Bareford D. Thrombocytopenia following routine blood transfusion: micro-aggregate blood filters prevent worsening thrombocytopenia in patients with low platelet counts. Vox Sang 1989; 56:40-1. [PMID: 2916335 DOI: 10.1111/j.1423-0410.1989.tb03046.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
11 patients with anaemia and thrombocytopenia due to bone marrow failure each received 2 sets of red-cell transfusions. They were randomised to receive 1 blood transfusion through a standard 170-micron giving set filter and another through a 40 micron micro-aggregate filter. After transfusion, the mean fall in platelet count was 15 x 10(9)/l (41.7%) and 1.4 x 10(9)/l (4.6%), respectively (p less than 0.01). The results confirm the findings of a previous study which showed that micro-aggregate filters prevent a post-transfusional decrease in platelet counts. In addition, this new study shows that this is clinically relevant in patients who are thrombocytopenic at the time of their blood transfusion.
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Affiliation(s)
- S Lim
- Department of Haematology, Queen Elizabeth Hospital, Birmingham, UK
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478
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DeCamp DL, Lim S, Colman RF. Reaction of pyruvate kinase with the new nucleotide affinity labels 8-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-diphosphate and 5'-triphosphate. Biochemistry 1988; 27:7651-8. [PMID: 3207694 DOI: 10.1021/bi00420a012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Two new reactive nucleotides have been synthesized and characterized: 8-[(4-bromo-2,3-dioxobutyl)thio]adenosine 5'-diphosphate and 5'-triphosphate (8-BDB-TADP and 8-BDB-TATP). ADP or ATP was converted to 8-thio-ADP (-ATP) via 8-bromo-ADP (-ATP), followed by condensation with 1,4-dibromobutanedione. Rabbit muscle pyruvate kinase is inactivated by both reagents in a biphasic manner with an initial rapid loss of 75% activity, followed by a slow total inactivation. The initial fast reaction with both compounds exhibits nonlinear dependence on reagent concentration, indicating formation of a reversible enzyme-reagent complex prior to covalent attachment. The presence of the gamma-phosphoryl group improves the performance of the affinity label: KI values for the fast phase are similar (about 100 microM), whereas kmax for 8-BDB-TATP is about three times greater than that of 8-BDB-TADP (0.286 min-1 vs 0.0835 min-1). After an 80-min incubation with 175 microM of either reagent, about 2 mol/mol of subunit is incorporated with 76% inactivation caused by 8-BDB-TADP and 97% inactivation by 8-BDB-TATP. Loss of activity is prevented by substrates, with the best protection afforded by a combination of ATP, Mn2+, K+, and phosphoenolpyruvate. Reaction of pyruvate kinase with either compound in the presence of protecting ligands leads to incorporation of about 1 mol of reagent/mol of subunit with only about 15% loss of activity. These results suggest that 8-BDB-TADP and 8-BDB-TATP react with two groups on the enzyme, one of which is at or near the active site.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- D L DeCamp
- Department of Chemistry and Biochemistry, University of Delaware, Newark 19716
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479
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Tighe H, Friend PJ, Collier SJ, Decurtins M, Lim S, Cobbold SP, Thiru S, Calne RY, Waldmann H. Delayed allograft rejection in primates treated with anti-IL-2 receptor monoclonal antibody Campath-6. Transplantation 1988; 45:226-8. [PMID: 3122385 DOI: 10.1097/00007890-198801000-00047] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- H Tighe
- Department of Pathology, University of Cambridge, United Kingdom
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480
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Collier DS, Calne R, Thiru S, Friend PJ, Lim S, White DJ, Kohno H, Levickis J. FK-506 in experimental renal allografts. Transplant Proc 1987; 19:3975-7. [PMID: 2445063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- D S Collier
- Department of Surgery, University of Cambridge, Addenbrooke's Hospital, United Kingdom
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481
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Friend PJ, Tighe H, Lim S, Collier DS, Decurtins M, Gilliland LK, Thiru S, Calne R, Waldmann H. The use of monoclonal antibodies against activated human T cells following renal allografting in the baboon. Transplant Proc 1987; 19:4317-8. [PMID: 3314035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- P J Friend
- Department of Surgery, University of Cambridge, UK
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482
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483
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Chew RK, Lim S, Cheng C, Foong WC. Acute cholangitis in Singapore. Ann Acad Med Singap 1986; 15:172-5. [PMID: 3530103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
115 cases of acute calculous cholangitis were analysed for their presentations, treatment and complications. There were slightly more Chinese males than females (1.4:1) and the mean age was 62 years old. Though pain was the commonest symptom (95.7%), only 35.7% of patients had complete Charcot's triad. 21.7% presented in septicaemic shock. E. Coli and Klebsiella were the commonest organisms isolated. All patients had cholecystectomy and exploration of common bile ducts. Twenty patients had additional choledochontrostomy performed. 50.4% of patients developed complications and the overall mortality was 16.5%. Patients over 60 presented in shock carried a significantly higher mortality (40%).
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484
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Abstract
Pollens of closely related species often share common antigens and allergens although this is not always the case. Four species of Oleaceae pollens commonly found in the Mediterranean area were investigated for cross-reactivity: olive (Olea europaea), ash (Fraxinus exselsior), privet (Ligustrum vulgare) and Phillyrea angustifolia, a common bush. Twenty individual sera of patients allergic to Oleaceae were investigated for specific IgE antibodies against the four species of Oleaceae pollens. The results indicated a high degree of correlation between RAST titres of Oleaceae pollens but three gave a particular emphasis on one species only. Cross-reactivity among these four pollen species was sought by means of RAST inhibition, iso-electric focusing and tandem cross-immunoelectrophoresis. All tests revealed a high degree of cross reactivity although there is no total identity among these four pollen species.
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485
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486
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Jacobs HK, Lim S, Salem MR, Rao TL, Mathru M, Smith BD. Cardiac electrophysiologic effects of pancuronium. Anesth Analg 1985; 64:693-9. [PMID: 4014730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A microelectrode examination of guinea pig left ventricular papillary muscle was performed to determine whether there was a direct effect of pancuronium on cardiac cells and, if so, to attempt to ascertain the mechanism of this effect. Electrical events were measured before and during superfusion with pancuronium, epinephrine, propranolol, and verapamil; alone and in various combinations. Pancuronium prolonged the duration of the action potential (AP); increased resting potential (Em), AP magnitude, and rate of rise of the AP (dV/dt); and resulted in spontaneity in 12% of the muscles. Epinephrine and pancuronium combined caused spontaneity in 80% of the muscles and oscillatory behavior. Additionally, this combination decreased AP magnitude, Em, and dV/dt in several preparations--a pattern of response similar to that seen in ouabain-treated myocardial cells under the influence of catecholamines. These changes were always reversed by verapamil or by perfusion with a drug-free medium, and were usually reversed by propranolol. The data suggest a combined pancuronium/epinephrine induced increase in cardiac membrane permeability to Ca2+.
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487
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Lim S, Daruwalla JS, Wee A. Tumoral calcinosis--a case report. Ann Acad Med Singap 1985; 14:391-3. [PMID: 4037699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Tumoral Calcinosis is a well established but rare clinical entity. It was first described in 1899, and since then, scattered reports have occurred in the literature from many parts of the world. The main controversy lies in the aetiology of the condition. One such case is presented in this paper, along with a review of the literature.
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488
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Pho RW, Chow J, Lim S, Wong HK. Rehabilitation of newly reconstructed thumb. Ann Acad Med Singap 1983; 12:380-6. [PMID: 6678120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This paper documents the rehabilitation of newly reconstructed thumb using five different techniques of creating a new thumb. We have attempted to assess the functional usefulness that each method offers to the recipient hand.
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489
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Linder MC, Bryant RR, Lim S, Scott LE, Moor JE. Ceruloplasmin elevation and synthesis in rats with transplantable tumors. Enzyme 1979; 24:85-95. [PMID: 456340 DOI: 10.1159/000458636] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In rats with transplantable mammary or hepatic tumors, plasma ceruloplasmin oxidase activity was increased 50--200%. This occurred progressively with tumors weighing 0.3% of body weight of more, and did not occur upon sham operation or implantation of normal tissue. Incorporation of [3H]-leucine indicated a specific enhancement of ceruloplasmin synthesis in the tumor-bearing rats, and a greater state of activation of the enzyme was also observed. The mechanism of the increase in ceruloplasmin levels in rats and humans with cancer thus appears to involve increased synthesis and activation of the enzyme.
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490
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491
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Homburger F, Russfield AB, Weisburger JH, Lim S, Chak SP, Weisburger EK. Aging changes in CD-1 HaM/ICR mice reared under standard laboratory conditions. J Natl Cancer Inst 1975; 55:37-45. [PMID: 169366 DOI: 10.1093/jnci/55.1.37] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Three hundred CD-1 HaM/ICR mice were observed for 2 years, and useful necropsies were done on 99 males and 102 females. Mortality was 50% at 16 months in the males and 18 months in the females. Among mice that came to autopsy, total tumor incidence was 54% for males and 75% for females, with most neoplasms occurring after 18 months. Adenomas or adenocarcinomas of the lung were the most frequent, followed by lymphoreticular tumors, vascular tumors, hepatomas, subcutaneous fibrosarcomas, and adenocarcinomas of the mammary glands. Some degree of amyloidosis was seen in half the mice of both sexes, beginning at 8 months in males and 12 months in females. Variability in tumor incidence among small groups if mice emphasized the need for adequate samples.
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492
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Delaveau P, Lim S. [Chemical, pharmacologic and clinical study of traditional and modern chewing materials. I. Analysis of chewing gums]. Ann Pharm Fr 1975; 33:221-7. [PMID: 1211786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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493
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Abstract
A sucrose diet supported implantation of Odontomyces viscosus and a caries-inducing streptococcus in albino hamsters. Caries and periodontal disease occurred simultaneously when both types of bacteria were implanted. Odontomyces, but not the streptococcus, became implanted in albino hamsters on a starch diet. Glucose and fructose diets also supported implantation of odontomyces and development of periodontal disease in golden hamsters. Caries development was minimal.
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494
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Abstract
The authors present some physiological parameters involved in levan formation by Odontomyces viscosus, a filamentous organism in gingival plaque of the hamster.
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495
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496
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497
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