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Lim KH, Liam CK, Vasudevan AE, Wong CM. Giant cell arteritis presenting as chronic cough and prolonged fever. Respirology 1999; 4:299-301. [PMID: 10489679 DOI: 10.1046/j.1440-1843.1999.00195.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 62-year-old man presented with a 3-month history of chronic non-productive cough and unexplained fever. Further questioning revealed that he had headaches and myalgia. Bilateral thickened temporal arteries were noted on physical examination. The erythrocyte sedimentation rate was 96 mm in 1 h. A biopsy specimen of the left temporal artery showed inflammatory changes consistent with the diagnosis of giant cell arteritis. Commencement of prednisolone resulted in rapid and dramatic resolution of his symptoms. Physicians should be aware of respiratory symptoms in patients with giant cell arteritis in order to avoid delay in diagnosis and therapy of this condition.
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Lim KH, Yap KB. The prescribing pattern of outpatient polyclinic doctors. Singapore Med J 1999; 40:416-9. [PMID: 10489511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
OBJECTIVE This study aims to analyse the prescribing pattern of doctors working in a government outpatient polyclinic in Singapore. DESIGN Retrospective study of 1 week of prescription scripts in 1996. MAIN OUTCOME MEASURES Number, types and duration of drugs prescribed; combination of drugs; age distribution; bad handwriting. RESULTS Two thousand six hundred and seventy-nine scripts were analysed. The age of patients ranged from 1 to 93 years with a mean of 43.8 years. There were 44.0% males and 56.0% females. The overall mean of 'total number of drugs prescribed' was 2.8 items. The means of 'number of drug items prescribed for more than 1 week' by age-group were: < 20 years = 0.2, 20 to < 40 years = 0.5, 40 to < 60 years = 1.3 and > 60 years = 2.4. One way analysis of variance showed significant difference between the means of each age-group. Post hoc analysis revealed that the oldest age group accounted for most of this significant result. The top 10 drugs prescribed in descending order were: antihistamines, paracetamol, throat medications (eg. lozenges, gargles, etc), nifedipine, beta-blockers, antacids, mist benadryl expectorant, Procodin cough syrup (containing codeine and promethazine), amoxycillin and vitamin B. Nifedipine and beta-blockers were the most commonly prescribed anti-hypertensives. Non-steroidal anti-inflammatory drugs were usually prescribed with antacids. One hundred and twenty (4.5%) scripts were illegible. CONCLUSION This study provides a baseline data for monitoring future prescribing trends. There may be a need to re-evaluate the appropriateness of nifedipine as the first line anti-hypertensive drug and the usefulness of NSAID-antacid and amoxycillin-cloxacillin combinations. The prevalence of illegible handwriting was high.
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Abstract
Cryptococcal infection uncommonly presents with pulmonary manifestations and even more rarely so as massive bilateral effusions. Pleural involvement is usually associated with underlying pulmonary parenchymal lesions and is unusual while on antifungal therapy. We report a patient with cryptococcal meningitis who, while on intravenous 5-flucytosine and amphotericin B, developed life-threatening bilateral massive pleural effusions with evidence of spontaneous resolution, consistent with prior hypothesis of antigenic stimulation as the cause of pleural involvement.
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Liam CK, Lim KH, Wong CM, Tang BG. Attitudes and knowledge of newly diagnosed tuberculosis patients regarding the disease, and factors affecting treatment compliance. Int J Tuberc Lung Dis 1999; 3:300-9. [PMID: 10206500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
SETTING An urban university teaching hospital. OBJECTIVES To determine patients' attitudes to tuberculosis and their knowledge of the disease, and factors associated with treatment compliance. DESIGN All adult patients commenced on treatment for tuberculosis from September 1994 to February 1996 were interviewed on initiation of treatment. To assess patient compliance with treatment, hospital clinical records were reviewed retrospectively. RESULTS A total of 135 patients with a mean age (+/-SD) of 41.9 (+/-17.4) years (range 15-84 years) were interviewed. The patients had limited understanding and knowledge about tuberculosis. There was a negative correlation between patient age and tuberculosis knowledge score (r = -0.18, P = 0.038). Patients with tertiary education had better knowledge than the others. Of 118 patients who were followed-up in our chest clinic, 80 (67.8%) completed the prescribed treatment. Compliance with treatment and follow-up was not affected by age, sex, ethnic group, educational level, occupation, extent of knowledge, tuberculosis symptoms, hospitalisation for tuberculosis or duration of the prescribed treatment regimen. There was a trend toward poorer compliance among patients who equated disappearance of tuberculosis symptoms with cure of the disease. CONCLUSIONS Malaysian patients with newly diagnosed tuberculosis attending a university teaching hospital had misconceptions and limited knowledge about the disease and its treatment. Educational background was an important determinant of a patient's level of knowledge about tuberculosis. Compliance was not affected by patient characteristics. Adequate counselling and education of patients and close relatives on tuberculosis and the necessity for prolonged treatment may help to improve treatment compliance.
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Lim KH, Chong KL. Multiple organ failure and septic shock in disseminated tuberculosis. Singapore Med J 1999; 40:176-8. [PMID: 10402899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The diagnosis of disseminated tuberculosis should be entertained in all patients with unexplained fever associated with hepatomegaly and/or splenomegaly with or without anomalies in liver function tests and haemogram. It should be considered as a possible cause of septic shock especially in patients with typical risk factors such as advanced age, diabetes, alcoholism or immunosuppression. Prompt therapy could be life saving in an otherwise potentially fatal condition. It is therefore appropriate to initiate anti-tuberculosis treatment as soon as such a diagnosis is suspected and not await final confirmation.
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Lim KH, Griffiths EJ, Pryn SJ, Callaway M, Angelini GD. Left ventricular volume reduction: new dawn or false horizon? Basic science and clinical doubts. J Card Surg 1999; 14:38-45. [PMID: 10678445 DOI: 10.1111/j.1540-8191.1999.tb00949.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Left ventricular volume reduction surgery (LVVR) for end-stage dilated cardiomyopathy is a surgical option used selectively but with unclear long-term results. Increasing numbers of reports are appearing in the literature. These should be pooled into an international registry through collaborative efforts that allow for more effective analysis. Furthermore, high priority must be given to identify subgroups of patients who will potentially gain most benefit from LVVR. Basic science may add invaluable data and in this article we describe how intraoperative myocardial biopsies from patients with idiopathic dilated cardiomyopathy were utilized to isolate myocytes in an effort to determine differential physiological characteristics at the cellular level. The result showed various degrees of contractile anomalies in response to electrical stimulation associated with defective calcium handling as reflected by measurements of calcium transients. It is hoped that this approach may be extended to preoperative catheter biopsy to gain information that will facilitate patient selection to avoid unnecessary surgical failures.
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Lim KH, Grey CP. Analysis of the anisotropic dimension in the RIACT (II) multiple quantum MAS NMR experiment for I = 3/2 nuclei. SOLID STATE NUCLEAR MAGNETIC RESONANCE 1998; 13:101-112. [PMID: 9875608 DOI: 10.1016/s0926-2040(98)00070-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Numerical simulations of the anisotropic dimension of the Rotation-Induced Adiabatic Coherence Transfer (RIACT) MQ experiment have been performed as a function of the asymmetry parameter, eta, for different spacings between the triple quantum (3Q) excitation and 3Q to single quantum (1Q) reconversion pulses. Large distortions of the spectra are observed, in comparison to the spectra obtained with 1D MAS NMR methods. The method is very sensitive to the relative orientation of the quadrupolar tensor and rotor axis, and signal can only be obtained from a maximum of 60% of the powder. The intensity varies with the spacing between the two pulses, t1, reaching a minimum of 30% when t1 is either a multiple of a full rotor period (n tau(r)) or for (n + 1/2) rotor periods, for pulse lengths (tau1SL) of a quarter of a rotor period. The maximum of 60% is obtained when t1 = n tau(r) - tau1SL. Experimental spectra were acquired for anhydrous Na2HPO4. Good fits were obtained between the experimental and simulated spectra, even for the non-rotor synchronized experiment, by choosing fixed values of t1. The simulations allowed the quadrupole coupling constants and asymmetry parameters to be extracted from the experimental data.
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Liam CK, Lim KH, Srinivas P, Poi PJ. Hypercalcaemia in patients with newly diagnosed tuberculosis in Malaysia. Int J Tuberc Lung Dis 1998; 2:818-23. [PMID: 9783529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
SETTING University Hospital, Kuala Lumpur, Malaysia. OBJECTIVE To determine the incidence of hypercalcaemia in Malaysian patients with newly diagnosed tuberculosis (TB) before the commencement of antituberculosis treatment. DESIGN A prospective study of consecutive patients with newly diagnosed bacteriologically and/or histologically proven tuberculosis in our institution from September 1994 to March 1996. RESULTS Of a total of 120 patients (67 males, 53 females), 68 had pulmonary TB, nine had pulmonary and pleural TB, 18 had pleural TB without chest radiograph evidence of lung involvement, 16 had various other forms of extra-pulmonary TB and nine had disseminated TB. The mean age of the patients was 44.3 (+/-18.0) years. The mean albumin-adjusted serum calcium concentration was 2.53 (+/-0.22) mmol/l. Hypercalcaemia was present in 27.5% of the patients, but only 12% of these patients showed symptoms of hypercalcaemia. The type of TB and, in the case of pulmonary TB, the radiographic extent of lung involvement, had no effect on the serum calcium level. CONCLUSION Hypercalcaemia is not uncommon among Malaysian patients with newly diagnosed TB, but it is rarely symptomatic.
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Lim KH, Callaway M, Angelini GD. Left ventricular volume reduction for end-stage heart failure: intrapapillary or extrapapillary resection, mitral valve repair or replacement? THE JOURNAL OF HEART VALVE DISEASE 1998; 7:484-7. [PMID: 9793843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We report on two patients with end-stage dilated cardiomyopathy and functional mitral valve insufficiency who underwent left ventricular volume reduction. Intrapapillary resection and correction of the mitral valve regurgitation produced inadequate reduction of the ventricular cavity and resulted in inability to wean the patients from cardiopulmonary bypass. Following extension of the resection to include the papillary muscles and mitral valve replacement, there was a significant improvement in cardiac function. Both patients survived surgery; subsequent echocardiography provided evidence of improved myocardial function and NYHA functional class.
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Liam CK, Lim KH. Awareness of the ozone layer and acceptance of a new CFC-free metered dose inhaler among asthmatic patients. Int J Tuberc Lung Dis 1998; 2:683-9. [PMID: 9712285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
SETTING University of Malaya Medical Centre, Kuala Lumpur, Malaysia. OBJECTIVE To assess the awareness of the ozone layer and the acceptance of the new non-chlorofluorocarbon (CFC) propellant hydrofluoroalkane 134a salbutamol pressurised metered dose inhaler (MDI) Airomir among asthmatic patients. DESIGN A total of 113 consecutive asthmatic patients aged 12 years and above from the out- and in-patient services of the hospital were interviewed using a questionnaire. RESULTS Sixty-five per cent of the patients were aware of the existence of the ozone layer, 23% that CFCs play a role in ozone depletion, and only 10% that current MDIs contained CFCs. All the patients felt that pressurised MDIs should be made CFC-free after they had considered the role of CFCs in the destruction of the ozone layer. Eighty-one per cent of 94 patients who preferred the Airomir inhaler over a multi-dose dry powder inhaler for administering bronchodilator medications were willing to switch to the new inhaler once it became available on the market. CONCLUSION Awareness of the damaging effect of CFCs on the ozone layer among asthmatic patients would encourage them to change to an ozone-friendly, CFC-free pressurised MDI.
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Taylor RN, de Groot CJ, Cho YK, Lim KH. Circulating factors as markers and mediators of endothelial cell dysfunction in preeclampsia. SEMINARS IN REPRODUCTIVE ENDOCRINOLOGY 1998; 16:17-31. [PMID: 9654604 DOI: 10.1055/s-2007-1016249] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
During the past decade a new hypothesis has been formulated that explains many of the disparate findings associated with the pregnancy syndrome preeclampsia. With an increased awareness of the physiological significance of vascular endothelial cell function, the seemingly unrelated signs of hypertension, proteinuria, edema, and hypercoagulability have converged to provide clinical evidence of a unifying pathophysiological mechanism: systemic, maternal endothelial cell dysfunction. Investigators have attempted to test this hypothesis through two approaches. The first approach involves the identification of in vivo markers of vascular endothelial cell injury in women with clinically evident preeclampsia. The second approach focuses on the ability of circulating factors derived from the serum or plasma of patients afflicted with preeclampsia to perturb endothelial cell function in vitro. In this review we summarize the increasingly compelling evidence that maternal vascular endothelial cells are a critical target for toxic humoral activities that precipitate the multifaceted preeclampsia syndrome.
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McMaster M, Zhou Y, Shorter S, Kapasi K, Geraghty D, Lim KH, Fisher S. HLA-G isoforms produced by placental cytotrophoblasts and found in amniotic fluid are due to unusual glycosylation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 160:5922-8. [PMID: 9637505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The human placenta expresses HLA-G, a nonclassical (class Ib) MHC molecule that could play a central role in maternal tolerance of the semiallogeneic fetus. In this work, we report the production of a new mAb, 4H84, that specifically reacts with HLA-G in two formats: immunocytochemistry and immunoblotting. Immunolocalization experiments with 4H84 confirmed our previous finding that cytotrophoblasts within the uterine wall are the only cells in tissue sections of placenta that express the HLA-G protein. Additional experiments showed that both amniocytes and cytotrophoblasts in the amnion-chorion express this protein. Since multiple HLA-G transcripts have been described, we used immunoblotting to study the HLA-G isoforms produced by cytotrophoblasts in vitro and by the amnion-chorion in vivo. Cytotrophoblasts, their conditioned medium, and amniotic fluid samples contained heterodisperse immunoreactive bands (Mr 35,000-50,000). N-deglycosylation by peptide-N-glycosidase F digestion resolved these isoforms into two distinct bands. Cell samples contained primarily an Mr 37,000-42,000 protein, most likely encoded by the full-length mRNA. Conditioned medium and amniotic fluid contained a slightly smaller protein, most likely the secreted form lacking the transmembrane and cytoplasmic regions. Removal of polylactosamine chains by endo-beta D-galactosidase digestion significantly reduced the electrophoretic mobility of the immunoreactive bands, suggesting that HLA-G, unlike class Ib molecules studied to date, carries N-acetyllactosamine units. These data show that Mr heterogeneity of HLA-G is due to its novel glycosylation, rather than to the translation of alternatively spliced mRNAs. We postulate that the unusual carbohydrate structures this molecule carries could interact with maternal immune cells and/or stabilize the molecule.
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Lim KH, Friedman SA, Ecker JL, Kao L, Kilpatrick SJ. The clinical utility of serum uric acid measurements in hypertensive diseases of pregnancy. Am J Obstet Gynecol 1998; 178:1067-71. [PMID: 9609585 DOI: 10.1016/s0002-9378(98)70549-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Our purpose was to evaluate the clinical utility of serum uric acid measurements in the hypertensive diseases of pregnancy. STUDY DESIGN We performed a nested case-control study to assess the clinical utility of serum uric acid measurements in women with hypertensive diseases of pregnancy. We identified 344 women who had serum uric acid measurements at term and categorized them into five diagnostic groups according to definitions of hypertensive diseases in pregnancy published by the National Working Group on Hypertension in Pregnancy: transient hypertension of pregnancy (n = 69), preeclampsia (n = 130), chronic hypertension (n = 23), chronic hypertension with superimposed preeclampsia (n = 29), and normal (n = 93). We compared the mean uric acid concentration for each group with use of a one-way analysis of variance and Scheffe's post hoc test and calculated the sensitivities and specificities in diagnosing preeclampsia as well as the likelihood ratios for serum uric acid values of 5.5, 6.0, and 6.5 mg/dl. We also examined the correlation between serum uric acid levels and several clinical outcome measures in women with hypertensive diseases of pregnancy. RESULTS The mean serum uric acid values for women with preeclampsia (6.2 +/- 1.4 mg/dl) and transient hypertension (5.6 +/- 1.7 mg/dl) were significantly higher than those of controls (4.3 +/- 0.8 mg/dl, p < 0.05). The difference in mean serum uric acid values between women with chronic hypertension (4.9 +/- 1.0 mg/dl) and superimposed preeclampsia (5.8 +/- 1.4 mg/dl) were not statistically significant. The likelihood ratio of having preeclampsia with a serum uric acid value of 5.5 mg/dl was 1.41 in gestational hypertension of pregnancy and 2.5 in chronic hypertension. With use of a receiver-operator characteristic curve, we were unable to identify a serum uric acid value that could be used to differentiate various hypertensive diseases of pregnancy. There was a weak correlation between serum uric acid values and several clinical outcome measures of preeclampsia (r = 0.06 to 0.26). CONCLUSION Although mean serum uric acid values are elevated in women with preeclampsia, the clinical utility of serum uric acid values in differentiating various hypertensive diseases of pregnancy appears to be limited. In the setting of chronic hypertension, however, a serum uric acid level of > or = 5.5 mg/dl could identify women with an increased likelihood of having superimposed preeclampsia.
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Rohde LH, Janatpore MJ, McMaster MT, Fisher S, Zhou Y, Lim KH, French M, Hoke D, Julian J, Carson DD. Complementary expression of HIP, a cell-surface heparan sulfate binding protein, and perlecan at the human fetal-maternal interface. Biol Reprod 1998; 58:1075-83. [PMID: 9546743 DOI: 10.1095/biolreprod58.4.1075] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The human hemochorial placenta is a structure formed by the invasion of cytotrophoblasts into the uterus. Previous studies from our laboratory have demonstrated a role for heparan sulfate proteoglycans (HSPGs) and their binding proteins in interactions between human trophoblastic and uterine cell lines in vitro. In this study, expression of both mRNA and protein of a novel, cell surface, heparin/heparan sulfate interacting protein (HIP), by human trophoblastic cell lines-i.e., JAR, JEG, and BeWo-and by human cytotrophoblast was examined throughout gestation. Immunohistochemistry of the human fetal-maternal interface demonstrated abundant HIP expression in cytotrophoblast cells, with lesser staining in syncytiotrophoblast and little or no staining in surrounding stromal or decidual cells. Staining with antibodies to the basement membrane HSPG, perlecan, demonstrated a pattern of staining complementary to that of HIP. Cytotrophoblasts in the uterine stroma, not affiliated with attached villi, displayed a less intense deposition of perlecan. In vitro binding studies of 125I-perlecan to a 17-amino acid synthetic peptide sequence of HIP, which has a high affinity and specificity for heparin/heparan sulfate, indicates that perlecan binds to the HIP peptide with high affinity (KDapp = 0.6 nM) and in a heparin-inhibitable manner. Furthermore, HIP antibodies inhibited by 61-88% in vitro invasion by trophoblasts in assays using primary cultures of normal human cytotrophoblasts. Consistent with this was the observation that immunohistochemically detectable HIP expression was greatly reduced in pre-eclamptic cytotrophoblasts, a condition in which trophoblast invasion is abnormally shallow. It is suggested that HIP potentiates human cytotrophoblast interactions with HSPGs, in vivo, and facilitates trophoblast invasion processes.
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Lim KH. Registration of new blindness in Singapore for 1985-1995. Singapore Med J 1998; 39:104-6. [PMID: 9632967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Data on causes of blindness in Singapore from blind registration have been gathered yearly since 1950, when blind registration in Singapore was first started. The blind register is maintained by the Singapore Association of the Visually Handicapped (SAVH), based on reports from practising ophthalmologists in the government institutions. Ophthalmologists in the private sector (who also attend to the bulk of patients coming from overseas) do not register their blind patients. During the past four decades (from 1950 till 1990), analyses of our causes of blindness have been published by various local authors, quoting data from the blind register at the SAVH. These reports showed that our pattern of blindness reflected predictably the trend already observed in the developed countries, viz a shift from infections to congenital and age-related causes. This trend is in keeping with the impact of affluence on the economic and social environment, resulting in better health services and the prevention of avoidable diseases. Updated but hitherto unpublished new blind registrations in Singapore for 1985-1995 confirm the now established trend. As of now (in 1995), retinal diseases is the ranking cause (57.6%), followed by congenital and developmental disorders (14.7%), optic atrophy (9.3%), glaucoma (8.6%) and minor causes (1%).
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Lim KH, Zhou Y, Janatpour M, McMaster M, Bass K, Chun SH, Fisher SJ. Human cytotrophoblast differentiation/invasion is abnormal in pre-eclampsia. THE AMERICAN JOURNAL OF PATHOLOGY 1997; 151:1809-18. [PMID: 9403732 PMCID: PMC1858365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
During human placental development, cytotrophoblast stem cells differentiate and invade the uterus. Simultaneously, the cells modulate their expression of several classes of stage-specific antigens that mark transitions in the differentiation process and play a role in either uterine invasion (integrin cell-extracellular matrix receptors and matrix metalloproteinase-9) or immune interactions (HLA-G). The pregnancy disease pre-eclampsia is associated with shallow cytotrophoblast invasion. Previously we showed, by immunofluorescence localization on placental tissue, that in pre-eclampsia invasive cytotrophoblasts fail to properly modulate their integrin repertoire. This finding suggests possible abnormalities in the differentiation pathway that leads to uterine invasion. Here we used a culture system that supports this differentiation process to compare the differentiative and invasive potential of cytotrophoblasts obtained from control (n = 8, 22 to 38 weeks) and pre-eclamptic (n = 9, 24 to 38 weeks) placentas. In culture, the cells from pre-eclamptic placentas failed to properly modulate alpha1 integrin and matrix metalloproteinase-9 expression at the protein and mRNA levels. Their invasive potential was also greatly reduced. Likewise, the cells failed to up-regulate HLA-G protein and mRNA expression. These results suggest that defective cytotrophoblast differentiation/invasion can have significant consequences to the outcome of human pregnancy (ie, development of pre-eclampsia) and that, by the time delivery becomes necessary, the defect is not reversed by removing the cells from the maternal environment.
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Yu YS, Kang YH, Lim KH. Improvements in visual acuity following limbal lensectomy for subluxated lenses in children. OPHTHALMIC SURGERY AND LASERS 1997; 28:1006-10. [PMID: 9427989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND OBJECTIVE To report the surgical results of limbal lensectomy using an automated vitrectomy instrument for the treatment of subluxated lenses in children. PATIENTS AND METHODS The authors reviewed the charts of children who underwent surgery for subluxated lenses. Limbal lensectomies with an "in the bag" technique were performed on 18 eyes of 10 patients. The indications for surgery were a best-corrected visual acuity of less than 20/60, bisection of pupil by the lens, or both. RESULTS Best-corrected visual acuity improved in all 18 eyes (paired t test, P < .01). In 1 eye, transient anterior chamber hyphema occurred during the early postoperative period. No other significant complications were found during an average follow-up of 19.6 months. CONCLUSION Limbal lensectomy for subluxated lenses in children improved visual acuity without severe complications.
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Lim YY, Lim KH. Interaction of Aqueous Solutions of a Surface Active Copper(II) Complex with Several Common Surfactants. J Colloid Interface Sci 1997; 196:116-9. [PMID: 9441659 DOI: 10.1006/jcis.1997.5180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Micellar properties of binary mixed surfactants of a surface active mixed copper(II) chelate, [Cu(C12-tmed)(acac)Cl] (where C12-tmed is N,N,N'-trimethyl-N'-dodecylethylenediamine) with three common surfactants, viz. sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and octaethylene glycol monododecyl ether (C12E8), were investigated by surface tensiometry, ESR, and UV-visible absorption techniques. The surface tension data were treated with Rubingh's method for mixed micelle formation and Rosen's method for mixed monolayer formation at the aqueous solution/air interface. It was found that in the mixed micelle there is strong attractive interaction between cationic copper surfactant and anonic dodecyl sulfate while there is almost ideal mixing between copper surfactant and CTAB and C12E8. From the ESR and UV-visible studies, a mixed block-type arrangement of head groups is proposed. Copyright 1997 Academic Press. Copyright 1997Academic Press
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Grullon KE, Feldstein VA, Lim KH. Elevated maternal serum alpha-fetoprotein associated with an asymptomatic tubal pregnancy at 20 weeks' gestation. Obstet Gynecol 1997; 90:682-5. [PMID: 11770596 DOI: 10.1016/s0029-7844(97)00388-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Most tubal ectopic pregnancies become symptomatic in the first trimester and rarely progress to the second trimester. Elevated maternal serum alpha-fetoprotein (MSAFP) has rarely been associated with second-trimester tubal pregnancy. We present a case of a 20-week asymptomatic tubal pregnancy identified by elevated MSAFP. CASE An asymptomatic 22-year-old woman at 20 weeks' gestation was evaluated with a targeted fetal survey for an abnormally elevated MSAFP. The ultrasound examination revealed an extrauterine gestation. The patient was taken to exploratory laparotomy, and a total salpingectomy was performed. CONCLUSION Although rare, a second-trimester ectopic pregnancy must be considered in the differential diagnosis of elevated MSAFP. A careful ultrasound scan should rule out an extrauterine pregnancy.
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Cammarano WB, Gray AT, Rosen MA, Lim KH. Anesthesia for combined cesarean section and extra-adrenal pheochromocytoma resection: a case report and literature review. Int J Obstet Anesth 1997; 6:112-7. [PMID: 15321292 DOI: 10.1016/s0959-289x(97)80008-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pheochromocytoma during pregnancy is unusual, with approximately 250 cases now reported in the literature. The current case describes the anesthetic management of a patient with a large extra-adrenal pheochromocytoma who underwent a combined cesarean section and tumor removal in which perioperative hemodynamic control was difficult despite high-dose a-adrenergic blockade. In this case it is believed that difficulty in perioperative hemodynamic management was related to mechanical stimulation of the tumor by the gravid uterus. Review of published case reports since 1980 reveals that a pheochromocytoma during pregnancy may be diagnosed in an extra-adrenal location relatively more commonly compared to non-pregnant patients. Established criteria exist for the adequacy of alpha- and beta-adrebergic blockade for the management of pheochromocytoma in the non-pregnant patient. We discuss how these criteria apply to pregnant patients with pheochromocytoma, and suggest possible modifications to the criteria.
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Yin Y, Lim KH, Weinbaum S, Chien S, Rumschitzki DS. A model for the initiation and growth of extracellular lipid liposomes in arterial intima. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 272:H1033-46. [PMID: 9124411 DOI: 10.1152/ajpheart.1997.272.2.h1033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
There is considerable evidence that lipoprotein cholesterol, after crossing the arterial endothelium and entering the intima from the vascular lumen, lodges in extracellular lipid packets (labeled "liposomes") bound to the extracellular matrix. These liposomes appear to form by occasional attachment of a low-density lipoprotein (LDL) to the intimal matrix and to grow in place mainly by appending available free LDL. The liposome size distributions observed in chronically hypercholesteremic (WHHL) and in short-term cholesterol-fed rabbits are quite different. We propose a hierarchy of simple nucleation-polymerization models to describe liposome formation and growth. Even the simplest of these (with only one adjustable parameter) agrees extremely well with the WHHL data. In contrast, the cholesterol-fed rabbit data seem to result from the short-term nonuniform intimal history of LDL supply, which is a consequence of the focal nature of the transendothelial LDL flow through isolated transient leakyjunctions. The same models used for the WHHL data, together with this intimal nonuniformity, superimposed on a slow uniform transendothelial seepage also account very well for this cholesterol-fed rabbit data.
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Lim KH, Kim HS, Yang YM, Lee SD, Kim WB, Yang J, Park JG. Cellular uptake and antitumor activity of the new anthracycline analog DA-125 in human cancer cell lines. Cancer Chemother Pharmacol 1997; 40:23-30. [PMID: 9137525 DOI: 10.1007/s002800050620] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To predict the clinical usefulness of DA-125, a newly developed doxorubicin analog, we compared its antitumor activity against 20 different human cancer cell lines with that of doxorubicin using the MTT in vitro chemosensitivity test. We also measured and compared the cellular uptake of this drug and doxorubicin in two cancer cell lines and their doxorubicin-resistant sublines. In the MTT test, DA-125 showed lower IC50 values than doxorubicin for 14 of 20 cell lines. DA-125 was more potent than doxorubicin for hepatocellular cancer cells with high mdr 1 expression. Among cancer cells from the stomach and colon, DA-125 was more potent than doxorubicin in 12 of 14 cell lines. We also investigated the cross-resistance of this drug with doxorubicin using four doxorubicin-resistant cancer cell sublines. Except in one cell line, there was very low cross-resistance. Cellular drug-uptake experiments were performed for two gastric cancer cell lines and their doxorubicin-resistant sublines. In this experiment, DA-125 was found to be very rapidly and completely converted to its active metabolite, M1, in the culture media. After this conversion, M1 was incorporated into these cancer cells more rapidly and reached higher intracellular concentrations than doxorubicin, suggesting that DA-125 (as M1) could achieve earlier and higher levels of intracellular accumulation than doxorubicin in its target tissues from the bloodstream. As a possible alternative antineoplastic agent to doxorubicin, DA-125 awaits further evaluation for its antitumor activity and toxicity.
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98
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Lim KH, Yu YS. Surgical management for persistent pupillary membrane with vitreous scissors. KOREAN JOURNAL OF OPHTHALMOLOGY 1996; 10:124-6. [PMID: 9055543 DOI: 10.3341/kjo.1996.10.2.124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Persistent pupillary membranes are common congenital disorders. To reduce the surgical complications, we used vitreous scissors instead of conventionally used Vannas scissors to remove the membrane and reviewed the surgical results. Five eyes of 4 children with persistent pupillary membrane were treated by surgery. Through the 1.5 mm limbal incision, the membrane was removed by using vitreous scissors after intracameral sodium hyaluronate. After 22.6 months follow-up, all pupils of operated eyes were round and no complications associated with the surgery were found. Three eyes showed improved visual acuities after the operation. We suggest that the surgery with vitreous scissors is better than with Vannas scissors.
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99
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Lim KH. Global blindness and the nation. Singapore Med J 1996; 37:419-23. [PMID: 8993146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this presentation, the major causes of blindness and blindness according to geographical regions are considered. World blindness has become a global problem and is different in various regions of the Third World. The problems of the developing countries require individual solutions. Prevention of blindness in Singapore and around the region is considered from a local perspective. A national consciousness that involves every ophthalmologist is required, just as every individual has a contribution to make towards the prevention of blindness.
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Shin HS, Lim KH. Spectroscopic and elemental investigation of microbial decomposition of aquatic fulvic acid in biological process of drinking water treatment. Biodegradation 1996; 7:287-95. [PMID: 8987887 DOI: 10.1007/bf00115742] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
As humic substances left in treated water tend to form trihalomethans during chlorination, their removal in water treatment processes is a significant concern for drinking water supplies. One of the removal technologies, the biofilm reactor is studied for the microbial decomposition of aquatic fulvic acid (AFA). The AFA is characterized by elemental analysis. UV-Vis, 13C-NMR, and IR spectroscopic methods. The spectroscopic and elemental investigation was capable of characterizing the microbial decomposition of AFA. Biologically treated fulvic acid was in a more oxidized state; its spectra displayed a higher degree of condensation of aromatic constituents than influent fulvic acid. Microbial degradation of AFA was more active in the low molecular weight fractions and intensively occurred in the aliphatic fraction.
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