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Huang TY, Lim HL. Electrogenic Staphylococcus warneri in lactate-rich skin. Biochem Biophys Res Commun 2022; 618:67-72. [PMID: 35716597 DOI: 10.1016/j.bbrc.2022.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 06/01/2022] [Accepted: 06/08/2022] [Indexed: 11/02/2022]
Abstract
The electrogenicity of environmental bacteria has been thoroughly explored and has been known to have the unique capability of decomposing hazardous chemicals for environmental remediation. However, electrogenic bacteria in human skin in regards to their electrical properties and locations have not yet been determined. Here, electrodermal activities and metabolite compositions at different locations of arm skin were assessed. Compared to the uppermost part of arm, we found that the forearm elicited high electrodermal activity and carried abundant lactate and alpha-ketoglutarate, two components commonly present in sweat. Upon culturing bacteria from the forearm, an iron-resistant strain of Staphylococcus warneri (S. warneri) was identified through 16S ribosomal RNA sequencing. Voltage changes induced by S. warneri in the presence of glucose were detected by two voltmeters of different electrode materials, demonstrating the electrogenicity of skin bacteria. Furthermore, we discovered that S. warneri has the ability to metabolize lactate to generate electricity. The results of this study reveal changes in skin conductance caused by bacterial electricity that are mediated by skin endogenous molecules and may provide a novel method of monitoring environmental skin insults.
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Affiliation(s)
- C P Teo
- Division of Haematology/Oncology, Department of Medicine, National University Hospital, Singapore
| | - H L Lim
- Division of Haematology/Oncology, Department of Medicine, National University Hospital, Singapore
| | - Y K Kueh
- Division of Haematology/Oncology, Department of Medicine, National University Hospital, Singapore
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Abstract
The integration of three-dimensional micropatterning with microfluidics provides a unique opportunity to create perfusable tissue constructs in vitro. Herein, we have used this approach to create a tumor-on-a-chip with an endothelial barrier. Specifically, we photopatterned a mixture of endothelial cells and cancer spheroids within a gelatin methacrylate (GelMA) hydrogel inside a microfluidic device. The differential motility of endothelial and cancer cells in response to a controlled morphogen gradient across the cell-laden network drove the migration of endothelial cells to the periphery while maintaining the cancer cells within the interior of the hydrogel. The resultant endothelial cell layer forming cell-cell contact via VE-cadherin junctions was found to encompass the entire GelMA hydrogel structure. Furthermore, we have also examined the potential of such a tumor-on-a-chip system as a drug screening platform using doxorubicin, a model cancer drug.
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Affiliation(s)
- Aereas Aung
- Department of Bioengineering, University of California-San Diego, La Jolla, CA, USA.
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Lim KH, Jasvindar K, Cheong SM, Ho BK, Lim HL, Teh CH, Lau KJ, Suthahar A, Ambigga D. Prevalence of smoking and its associated factors with smoking among elderly smokers in Malaysia: findings from a nationwide population-based study. Tob Induc Dis 2016; 14:8. [PMID: 27006650 PMCID: PMC4802631 DOI: 10.1186/s12971-016-0073-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 03/16/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The determination of smoking prevalence and its associated factors among the elderly could provide evidence-based findings to guide the planning and implementation of policy in order to will help in reducing the morbidity and mortality of smoking-related diseases, thus increase their quality of life. This paper describes the rate of smoking and identifies the factor(s) associated with smoking among the elderly in Malaysia. METHODS A representative sample of 2674 respondents was obtained via a two-stage sampling method in proportion to population size. Face-to-face interviews were conducted using a set of standardized validated questionnaire. Data was weighted by taking into consideration the complex sampling design and non-response rate prior to data analysis. Univariable and multivariable logistic regression were used to determine the factor/s associated with smoking. RESULTS The prevalence of non-smokers, ex-smokers and current smokers among Malaysians aged 60 years and above were 36.3 % (95 % CI = 32.7-39.8), 24.4 % (95 % CI = 21.2-27.5) and 11.9 % (95 % CI = 9.5-14.3), respectively. Current smokers were significantly more prevalent in men (28.1 %) than in women (2.9 %), but the prevalence declined with advancing age, higher educational attainment, and among respondents with known diabetes, hypertension and hypercholesterolemia. Multivariable analysis revealed that males (aOR, 18.6, 95 % CI 10.9-31.9) and other Bumiputras (aOR 2.58, 95 % CI 1.29-5.15) were more likely to smoke. in addition, elderly with lower educational attainment (aOR, 1.70, 95 % CI 1.24-7.41) and those without/unknown hypertension also reported higher likelihood to be current smokers (aOR 1.98, 95 % CI 1.35-2.83). However, there were no significant associations between respondents with no/unknown diabetes or hypercholesterolemia with smoking. CONCLUSIONS In short, smoking is common among elderly men in Malaysia. Therefore, intervention programs should integrate the present findings to reduce the smoking rate and increase the smoking cessation rate among the elderly in Malaysia and subsequently to reduce the burden of smoking-related disease.
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Affiliation(s)
- K H Lim
- Institute for Medical Research, Jalan Pahang, 50590 Kuala Lumpur, Malaysia ; Institute for Public Health, Jalan Bangsar, 50588 Kuala Lumpur, Malaysia
| | - K Jasvindar
- Institute for Public Health, Jalan Bangsar, 50588 Kuala Lumpur, Malaysia
| | - S M Cheong
- Institute for Public Health, Jalan Bangsar, 50588 Kuala Lumpur, Malaysia
| | - B K Ho
- Klang Health Department, Bandar Botanic Clinic, 41200 Klang, Selangor Malaysia
| | - H L Lim
- Melaka Manipal Medical College, Jalan Pengkalan Batu, Bukit Baru, 75150 Melaka Malaysia
| | - C H Teh
- Institute for Medical Research, Jalan Pahang, 50590 Kuala Lumpur, Malaysia
| | - K J Lau
- School of Medical Science, Universiti Sains Malaysia, Kuang Kerian, 15000 Kelantan, Malaysia
| | - A Suthahar
- Faculty of Medicine, University Teknologi Mara, Sg Buloh, 47000 Selangor, Malaysia
| | - D Ambigga
- Faculty of Medicine and Defence Health, University of Defence, Kem Sg. Besi, 57000 Kuala Lumpur, Malaysia
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Aung A, Bhullar IS, Theprungsirikul J, Davey SK, Lim HL, Chiu YJ, Ma X, Dewan S, Lo YH, McCulloch A, Varghese S. 3D cardiac μtissues within a microfluidic device with real-time contractile stress readout. Lab Chip 2016; 16:153-62. [PMID: 26588203 PMCID: PMC4681661 DOI: 10.1039/c5lc00820d] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present the development of three-dimensional (3D) cardiac microtissues within a microfluidic device with the ability to quantify real-time contractile stress measurements in situ. Using a 3D patterning technology that allows for the precise spatial distribution of cells within the device, we created an array of 3D cardiac microtissues from neonatal mouse cardiomyocytes. We integrated the 3D micropatterning technology with microfluidics to achieve perfused cell-laden structures. The cells were encapsulated within a degradable gelatin methacrylate hydrogel, which was sandwiched between two polyacrylamide hydrogels. The polyacrylamide hydrogels were used as "stress sensors" to acquire the contractile stresses generated by the beating cardiac cells. The cardiac-specific response of the engineered 3D system was examined by exposing it to epinephrine, an adrenergic neurotransmitter known to increase the magnitude and frequency of cardiac contractions. In response to exogenous epinephrine the engineered cardiac tissues exhibited an increased beating frequency and stress magnitude. Such cost-effective and easy-to-adapt 3D cardiac systems with real-time functional readout could be an attractive technological platform for drug discovery and development.
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Affiliation(s)
- Aereas Aung
- Department of Bioengineering, University of California-San Diego, La Jolla, CA, USA.
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In SM, Park DY, Sohn IK, Kim CH, Lim HL, Hong SA, Jung DY, Jeong SY, Han JH, Kim HJ. Experimental study of the potential hazards of surgical smoke from powered instruments. Br J Surg 2015; 102:1581-6. [PMID: 26331459 DOI: 10.1002/bjs.9910] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 05/05/2015] [Accepted: 07/06/2015] [Indexed: 11/09/2022]
Abstract
BACKGROUND Many surgical instruments have been replaced with powered devices in open gastrointestinal and laparoscopic surgery. The production of smoke as a result of vaporization of surgical tissue is inevitable, and exposure to surgical smoke is a long-standing concern. These vapours are potentially hazardous to patients and surgical teams. The present research was designed to compare various surgical devices to determine whether viable cells exist in their surgical smoke. METHODS The search for viable cells in surgical smoke was conducted using both in vitro and in vivo experiments. Various cancers were cauterized with electrocautery, radiofrequency ablation and ultrasonic scalpels, and the resulting surgical smoke was aspirated with Transwell(®) membrane; viable cells were sought in the surgical smoke. In an in vivo experiment, samples of SCC7 were cauterized with an ultrasonic scalpel and the sediment from the rinsed Transwell(®) membrane liquid after centrifugation was injected subcutaneously into the lower back of mice. RESULTS Viable cells were found only in the smoke from ultrasonic scalpels (in all 25 samples taken 5 cm from the cautery; 2 of 25 samples at 10 cm). Viable cells in the surgical smoke from ultrasonic scalpels implanted in mice grew in 16 of 40 injection sites. Histological and biochemical analyses revealed that these cancer cells were identical to the cancer cells cauterized by the ultrasonic scalpel. CONCLUSION Viable tumour cells are produced in the surgical smoke from tumour dissection by ultrasonic scalpel. Surgical relevance Surgical smoke is a byproduct of dissection using a number of powered devices. Hazards to operating room personnel and patients are unclear. This study has shown that use of an ultrasonic dissection device can produce smoke that contains viable tumour cells. Although the model is somewhat artificial, a theoretical risk exists, and measures to evacuate surgical smoke efficiently are important.
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Affiliation(s)
- S M In
- Department of Otolaryngology, School of Medicine, Konyang University, Daejeon, Korea
| | - D-Y Park
- Department of Otolaryngology - Head and Neck Surgery, Soonchunhyang University College of Medicine, Cheonan Hospital, Cheonan, Korea
| | - I K Sohn
- Departments of Otolaryngology, Ajou University, Suwon, Korea
| | - C-H Kim
- Departments of Otolaryngology, Ajou University, Suwon, Korea
| | - H L Lim
- Departments of Otolaryngology, Ajou University, Suwon, Korea
| | - S-A Hong
- Departments of Otolaryngology, Ajou University, Suwon, Korea
| | - D Y Jung
- Department of Otolaryngology, School of Medicine, Konyang University, Daejeon, Korea
| | - S-Y Jeong
- Departments of Medical Genetics, Ajou University, Suwon, Korea
| | - J H Han
- Departments of Pathology, School of Medicine, Ajou University, Suwon, Korea
| | - H J Kim
- Departments of Otolaryngology, Ajou University, Suwon, Korea
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Davey SK, Aung A, Agrawal G, Lim HL, Kar M, Varghese S. Embedded 3D Photopatterning of Hydrogels with Diverse and Complex Architectures for Tissue Engineering and Disease Models. Tissue Eng Part C Methods 2015; 21:1188-96. [PMID: 26154197 DOI: 10.1089/ten.tec.2015.0179] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Techniques that can create three-dimensional (3D) structures to provide architectural support for cells have a significant impact in generating complex and hierarchically organized tissues/organs. In recent times, a number of technologies, including photopatterning, have been developed to create such intricate 3D structures. In this study, we describe an easy-to-implement photopatterning approach, involving a conventional fluorescent microscope and a simple photomask, to encapsulate cells within spatially defined 3D structures. We have demonstrated the ease and the versatility of this approach by creating simple to complex as well as multilayered structures. We have extended this photopatterning approach to incorporate and spatially organize multiple cell types, thereby establishing coculture systems. Such cost-effective and easy-to-use approaches can greatly advance tissue engineering strategies.
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Affiliation(s)
- Shruti Krishna Davey
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California
| | - Aereas Aung
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California
| | - Gaurav Agrawal
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California
| | - Han Liang Lim
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California
| | - Mrityunjoy Kar
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California
| | - Shyni Varghese
- 1 Department of Bioengineering, University of California-San Diego , La Jolla, California.,2 Institute of Engineering in Medicine, University of California-San Diego , La Jolla, California
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Kabra H, Hwang Y, Lim HL, Kar M, Arya G, Varghese S. Biomimetic Material-Assisted Delivery of Human Embryonic Stem Cell Derivatives for Enhanced In Vivo Survival and Engraftment. ACS Biomater Sci Eng 2014; 1:7-12. [PMID: 26280019 DOI: 10.1021/ab500021a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The ability of human embryonic stem cells (hESCs) and their derivatives to differentiate and contribute to tissue repair has enormous potential to treat various debilitating diseases. However, improving the in vivo viability and function of the transplanted cells, a key determinant of translating cell-based therapies to the clinic, remains a daunting task. Here, we develop a hybrid biomaterial consisting of hyaluronic acid (HA) grafted with 6-aminocaproic acid moieties (HA-6ACA) to improve cell delivery and their subsequent in vivo function using skeletal muscle as a model system. Our findings show that the biomimetic material-assisted delivery of hESC-derived myogenic progenitor cells into cardiotoxin-injured skeletal muscles of NOD/SCID mice significantly promotes survival and engraftment of transplanted cells in a dose-dependent manner. The donor cells were found to contribute to the regeneration of damaged muscle fibers and to the satellite cell (muscle specific stem cells) compartment. Such biomimetic cell delivery vehicles that are cost-effective and easy-to-synthesize could play a key role in improving the outcomes of other stem cell-based therapies.
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Affiliation(s)
- Harsha Kabra
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Yongsung Hwang
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Han Liang Lim
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Mrityunjoy Kar
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Gaurav Arya
- Department of NanoEngineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Shyni Varghese
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
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9
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Chong CF, Khoo KL, Lim TK, Chang AY, Lim HL, Lee CN, Wong PS. Comparison of clinical with pathological nodal staging from systematic mediastinal lymph node dissection in early resectable non-small cell lung cancer. Singapore Med J 2007; 48:620-4. [PMID: 17609822] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
INTRODUCTION We compared the accuracy of clinical nodal (cN) status N0-1 with that of pathological nodal (pN) status obtained from systematic mediastinal lymph node dissection (SMLD) in primary non-small cell lung cancer. METHODS Data from 22 consecutive patients, who underwent lung cancer resection and SMLD of at least three mediastinal lymph node stations, from November 2001 to May 2003, were ana1ysed retrospectively. Only patients with cN0-1 status on computed tomography (CT) referred for surgery, were included in this study. RESULTS Mean age of patients was 66.6 +/- 8.1 years with a male to female ratio of 17:5. Mean number of lymph node stations dissected was 5.8 +/- 1.8. 41 percent had squamous cell carcinoma, 45.5 percent had adenocarcinoma, and 4.5 percent each had large cell carcinoma, bronchioalveolar carcinoma or a lymphoepithelial carcinoma. pN2 metastases were found in 27.3 percent of patients. The sensitivity of cN0-1 was only 12.5 percent, with a specificity of 92.9 percent and an area under the receiver operating characteristics curve of 0.53. The positive and negative predictive values of cN0-1 status were 50 percent and 65 percent, respectively, with an accuracy of 59 percent. 41 percent of patients were understaged with 27.3 percent in pathological stage III. Curative resections were achieved in 59 percent of patients. CONCLUSION The sensitivity of cN0-1 status based on CT alone is extremely poor when compared with pN status from SMLD. Based on cN0-1 status alone without SMLD, 27.3 percent of patients in pN2 would have been understaged. We recommend that all patients with cN0-1 status should undergo SMLD of at least three appropriate mediastinal node stations, for more accurate staging.
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Affiliation(s)
- C F Chong
- Department of Cardiac, Thoracic and Vascular Surgery, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074.
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Wong ASC, Soo RA, Lu JJ, Loh KS, Tan KS, Hsieh WS, Shakespeare TP, Chua ET, Lim HL, Goh BC. Paclitaxel, 5-fluorouracil and hydroxyurea concurrent with radiation in locally advanced nasopharyngeal carcinoma. Ann Oncol 2006; 17:1152-7. [PMID: 16684789 DOI: 10.1093/annonc/mdl090] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [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: 11/12/2022] Open
Abstract
BACKGROUND Concurrent chemoradiotherapy (CRT) is the standard treatment for locally advanced nasopharyngeal carcinoma (NPC). We conducted a phase II trial using paclitaxel, 5-fluorouracil and hydroxyurea concurrent with radiation (TFHX). PATIENTS AND METHODS Fifty-nine patients with locally advanced NPC were treated with CRT consisting of 4-day continuous infusions of paclitaxel (20 mg/m(2)/d) and 5-fluorouracil (600 mg/m(2)/d), and oral hydroxyurea 500 mg bid for nine doses, every 3 weeks concurrent with radiotherapy (RT). RT consisted of once daily 200cGy fractions 5 times per week to a total of 7000cGy. RESULTS Complete response was seen in 86% and 71% of patients at 4 and 12 months after CRT. The median follow-up was 34 months. Twenty-three patients experienced relapse. Sixteen deaths occurred: 13 from progressive disease. Three-year overall survival and progression-free survival were 72% and 54% respectively, with locoregional and distant control rates of 83% and 64% at 3 years respectively. Grade 3 to 4 acute toxicities included oropharyngeal mucositis in 81% of patients treated, dermatitis in 63%, weight loss in 32%, and neutropenia in 22%. Neutropenic fever was seen in 14%. There were no treatment-related deaths from acute toxicity. CONCLUSIONS TFHX is shown to be feasible in NPC. Non-cross resistant induction chemotherapy should be further studied with this regimen.
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Affiliation(s)
- A S C Wong
- Department of Hematology-Oncology, National University Hospital, Singapore.
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Soo RA, Wang LZ, Tham LS, Yong WP, Boyer M, Lim HL, Lee HS, Millward M, Liang S, Beale P, Lee SC, Goh BC. A multicentre randomised phase II study of carboplatin in combination with gemcitabine at standard rate or fixed dose rate infusion in patients with advanced stage non-small-cell lung cancer. Ann Oncol 2006; 17:1128-33. [PMID: 16670205 DOI: 10.1093/annonc/mdl084] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [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: 11/14/2022] Open
Abstract
BACKGROUND Intracellular gemcitabine triphosphate (dFdCTP) levels can be optimised by administering gemcitabine at a fixed dose rate infusion. PATIENTS AND METHODS Patients with chemonaive advanced non-small cell lung cancer (NSCLC) were randomised to receive gemcitabine at a fixed dose rate gemcitabine 750 mg/m(2) over 75 min (arm A) or gemcitabine 1000 mg/m(2) over 30 min (arm B) on days 1 and 8 every three week cycle. Carboplatin at AUC of 5 was administered in both treatment arms on day 1 of each cycle. End points were activity, tolerability and pharmacokinetics of plasma and intracellular gemcitabine. RESULTS 76 patients were randomised. Response rate was 34% in arm A and 42% in arm B. Toxicity and quality of life scores were similar for both treatment arms. Mean plasma Cmax(gemcitabine) and mean dFdCTP AUC in arm A was 20.8 microM +/- 17.2 microM and 35,079 +/- 18,216 microM*min respectively and in arm B, 41.2 +/- 13.9 microM and 32 249 +/- 11 267 microM*min respectively. dFdCTP saturation was reached in Arm B but not in Arm A. CONCLUSION The saturability of dFdCTP accumulation in Arm A suggests optimal delivery of gemcitabine is achieved using fixed rate infusion compared to 30-min infusion. Fixed dose rate gemcitabine is active and feasible, supporting the concept of fixed dosing rate of gemcitabine in advanced NSCLC. However, this entails a longer infusion time with associated higher costs involved.
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Affiliation(s)
- R A Soo
- Cancer Therapeutics Research Group, Department of Haematology-Oncology, National University Hospital, Singapore
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Schuetz EG, Relling MV, Kishi S, Yang W, Das S, Chen P, Cook EH, Rosner GL, Pui CH, Blanco JG, Edick MJ, Hancock ML, Winick NJ, Dervieux T, Amylon MD, Bash RO, Behm FG, Camitta BM, Raimondi SC, Goh BC, Lee SC, Wang LZ, Fan L, Guo JY, Lamba J, Lim R, Lim HL, Ong AB, Lee HS, Kuehl P, Zhang J, Lin Y, Assem M, Schuetz J, Watkins PB, Daly A, Wrighton SA, Hall SD, Maurel P, Brimer C, Yasuda K, Venkataramanan R, Strom S, Thummel K, Boguski MS. PharmGKB update: II. CYP3A5, cytochrome P450, family 3, subfamily A, polypeptide 5. Pharmacol Rev 2004; 56:159. [PMID: 15169924 DOI: 10.1124/pr.56.2.1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- E G Schuetz
- St. Jude's Children's Research Hospital, Memphis, Tennessee, USA
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Tan LK, Suri R, Lim HL, Ong SK. Immunoglobulin D multiple myeloma in our hospital--a rare occurrence. Singapore Med J 2000; 41:500-3. [PMID: 11281443] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Immunoglobulin (Ig) D multiple myeloma is a rare presentation, usually with an aggressive course and a poorer prognosis. It accounts for about 1-2% of newly diagnosed mulitple myeloma patients. Due to its rarity, reports on Ig D multiple myeloma are limited in the literature. We therefore present 4 cases of Ig D multiple myeloma in our hospital over a period of 8 years between 1990 to 1998. The average age of presentation of our patients was 44 years old with a female preponderance. Common presenting symptoms were appetite and weight loss and bone pain. Two patients presented with neurological symptoms and 2 with renal impairment. Three patients had an associated lambda paraproteinaemia and the fourth had a kappa paraproteinaemia. A common finding in Ig D myeloma is a small or no spike seen on serum electrophoresis together with heavy Bence Jones proteinuria. A review of the literature on Ig D myeloma is also presented.
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Affiliation(s)
- L K Tan
- Department of Laboratory Medicine, National University Hospital, Singapore
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14
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Goh BC, Lehnert M, Lim HL, Ng AW, Chan CC, Kong HL, Lee SC, Wee J, Chua ET, Wong JE. Phase II trial of docetaxel in Asian patients with inoperable stage III non-small cell lung cancer. Acta Oncol 2000; 39:225-9. [PMID: 10859016 DOI: 10.1080/028418600430824] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 01/28/2023]
Abstract
Docetaxel has a response rate of greater than 30% in first-line treatment of Western patients with advanced non-small cell lung cancer (NSCLC). The goal of this open-label. phase II study was to evaluate the activity and safety profile of docetaxel in Asian patients with inoperable untreated stage III NSCLC. Docetaxel was given at 100 mg/m2 as a 1-h infusion every 3 weeks. Prophylactic dexamethasone was given to reduce hypersensitivity reactions and edema. Thirty-five patients were enrolled in the study. The response rate was 34% (95% CI, 19%-50%) according to intent-to-treat analysis. No complete response was observed. Twenty-four patients (69%) had grade 3 or 4 neutropenia in cycle 1, and febrile neutropenia was seen in 12 patients. Six patients (17%) experienced mild fluid retention. Docetaxel is an active agent in first-line treatment of Asian patients with locally advanced NSCLC, with the main toxicity being neutropenia. Fluid retention was a minor problem in this study.
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Affiliation(s)
- B C Goh
- Department of Medical Oncology, National University Hospital, Singapore.
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15
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Lim HL, Lee SH. Issues in peripheral blood stem cell transplantation. Singapore Med J 1998; 39:388-9. [PMID: 9885715] [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: 02/09/2023]
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Lim HL, Teo CP, Wong K, Kueh YK. L-asparaginase induced intracranial haemorrhage in acute lymphoblastic leukemia. Singapore Med J 1998; 39:76-8. [PMID: 9652181] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A 20-year-old national serviceman with acute lymphoblastic leukaemia, developed a large left parieto-occipital haemorrhage 7 days after completion of induction chemotherapy. Severe hypofibrinogenemia had been noted while he was receiving L-asparaginase. The haemorrhage could not be attributed to thrombocytopenia, disseminated intravascular coagulopathy, arterio-venous malformation, berry aneurysm or leukaemic infiltration because each of these causes was carefully investigated into and excluded. We conclude that the intracranial haemorrhage was likely L-asparaginase induced, an uncommon but recognised complication associated with L-asparaginase therapy.
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Affiliation(s)
- H L Lim
- Department of Medicine, National University Hospital, Singapore
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Nelson DR, Lim HL, Marousis CG, Fang JW, Davis GL, Shen L, Urdea MS, Kolberg JA, Lau JY. Activation of tumor necrosis factor-alpha system in chronic hepatitis C virus infection. Dig Dis Sci 1997; 42:2487-94. [PMID: 9440625 DOI: 10.1023/a:1018804426724] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.2] [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: 02/05/2023]
Abstract
Tumor necrosis factor-alpha (TNF-alpha) plays a central role in the host's immunomodulatory response to infective agents. To evaluate the TNF-alpha system in patients with chronic hepatitis C virus (HCV) infection, plasma, serum, and peripheral blood mononuclear cells (PBMC) were prospectively collected from 53 patients and 33 healthy control subjects. Circulating TNF-alpha and TNF receptors were assayed by their respective enzyme immunoassays. In addition, TNF-alpha mRNA was quantitated in PBMC using a branched DNA assay, and production of TNF-alpha by PBMC with and without lipopolysaccharide was also assessed. Patients with chronic HCV infection had a higher level of circulating TNF-alpha compared to healthy control subjects (9.62 +/- 6.01 vs 3.66 +/- 1.23 pg/ml, P < 0.001). They also had higher circulating levels of TNF receptors compared to control (CD120a: 3323 +/- 1267, pg/ml, N = 49 vs 1855 +/- 422 pg/ml, N = 33, P < 0.001; CD120b: 1290 +/- 650 pg/ml, N = 51, vs 863 +/- 207 pg/ml, N = 33, P < 0.001). Plasma TNF-alpha level correlated with circulating CD120a (r = 0.52, N = 49, P < 0.001) and weakly with CD120b (r = 0.32, N = 51, P = 0.02). Plasma TNF-alpha also correlated with markers of hepatocellular injury, including ALT (r = 0.34, N = 53, P = 0.01) and alpha-GST (r = 0.31, N = 43, P = 0.042), but not with serum HCV RNA levels. There was no difference in the TNF-alpha mRNA levels in PBMC between patients with chronic HCV infection (1.4 +/- 1.9 units/10[6] cells, N = 8) and healthy control subjects (2.1 +/- 1.4 units/10[6] cells, N = 8, P = NS). There was also no difference in the spontaneous production of TNF-alpha by PBMC (1 x 10[6] cells/ml) between patients with chronic HCV infection (14.2 +/- 36.5 pg/ml, N = 11) and healthy subjects (11.9 +/- 14.0 pg/ml, N = 14, P = NS). However, patients with chronic HCV infection produced more TNF-alpha upon stimulation with lipopolysaccharide compared to healthy control subjects (1278 +/- 693 pg/ml, N = 11, vs 629 +/- 689 pg/ml, N = 14, P < 0.05). These data indicate that the TNF-alpha system is activated in patients with chronic HCV infection.
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Affiliation(s)
- D R Nelson
- Department of Medicine, University of Florida, Gainesville, USA
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18
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Nelson DR, Lim HL, Oliver D, Qian KP, Davis GL, Lau JY. alpha-Glutathione S-transferase as a marker of hepatocellular damage in chronic hepatitis C virus infection. Am J Clin Pathol 1995; 104:193-8. [PMID: 7639195 DOI: 10.1093/ajcp/104.2.193] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [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
alpha-Glutathione S-transferase (alpha GST) may be a good serologic marker of hepatocellular damage because of its low molecular weight, uniform hepatic distribution, high cytosolic concentration, and short half-life. To determine the clinical utility of alpha GST in patients with chronic hepatitis C virus (HCV) infection, serum alpha GST levels were measured in 96 patients with chronic HCV infection, of whom 47 subsequently underwent interferon-alpha therapy. Patients were simultaneously evaluated with conventional liver biochemistry, serum HCV RNA levels, and liver histology. Different methods of serum collection did not affect alpha GST values, indicating that this was a stable serum marker. In 93% of patients with chronic HCV infection, alpha GST was elevated and showed an excellent correlation with serum aminotransferases. Histologic analysis revealed a correlation of alpha GST with both lobular inflammation and bile duct lesions. There was no correlation between serum alpha GST levels and the demographic features, mode of transmission, virologic, other histologic parameters, or subsequent response to interferon-alpha. During serial monitoring in patients undergoing interferon-alpha therapy, elevation of serum alpha GST correlated with biochemical relapse and in some patients virologic relapse in the presence of normal liver biochemistry. alpha GST was persistently elevated in all nonresponders. Four of six of those patients who responded completely followed by early relapse had elevated alpha GST intermittently or continuously during therapy despite normalization of serum aminotransferases. Two of five of those with a complete and sustained response had elevated alpha GST during treatment and follow-up, and both were also seropositive for HCV RNA during follow-up. These data demonstrate that alpha GST is a stable marker, has similar diagnostic utility as serum aminotransferases, and may have a role in the monitoring of patients undergoing interferon-alpha therapy.
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Affiliation(s)
- D R Nelson
- Department of Medicine, University of Florida, JHMHC, Gainesville 32610, USA
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19
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Abstract
It has recently been proposed that a depletion of glutathione (GSH) may be a contributing factor to viral persistence and resistance to interferon-alpha (IFN-alpha) therapy in chronic hepatitis C virus (HC) infection. The aim of this study was: (1) to compare plasma GSH levels in patients with chronic HCV infection and normal healthy controls; and (2) to correlate GSH levels with liver histology and serum HCV RNA levels. Twenty-four patients with compensated chronic hepatitis C and 27 healthy subjects were studied. Serum and heparinized plasma were prospectively prepared and frozen within 1 h of collection. Plasma glutathione and glutathione peroxidase (GP) levels were measured spectrophotometrically. The serum HCV RNA level was quantitated by the branched chain DNA signal-amplification assay. Plasma GSH levels were not decreased in patients with chronic HCV infection but were actually greater than in controls (control 1.27 +/- 0.12 micrograms ml-1, HCV 1.62 +/- 0.11 micrograms ml-1, P < 0.05). There was also no difference in plasma GP activity between these two groups (control 0.233 +/- 0.007 U ml-1, HCV 0.230 +/- 0.007 U ml-1). Among the patients with chronic HCV infection, there was no correlation between either plasma GSH or GP levels and the serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST), serum HCV RNA level, or liver histology. This study demonstrates that chronic HCV infection does not decrease the plasma GSH and GP levels.
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Affiliation(s)
- H L Lim
- Section of Hepatobiliary Diseases, University of Florida College of Medicine, Gainesville, Florida, USA
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20
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Wong K, Lim HL, Teo CP, Tan YO, Kueh YK. Treatment of acute promyelocytic leukaemia in first relapse with all-trans retinoic acid. Ann Acad Med Singap 1995; 24:177-9. [PMID: 7605089] [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] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A 27-year-old Chinese woman with acute promyelocytic leukaemia in first relapse after the initial conventional induction chemotherapy 18 months earlier was treated with all-trans retinoic acid (ATRA) at an initial dose of 45 mg/m2 and subsequently increased to 65 mg/m2 on day 15. Complete remission was achieved after a total of 40 days of ATRA alone. Serial marrow examinations during induction showed progressive maturation of myelopoiesis without bone marrow hypoplasia. There was a significant reduction in number of cells with the t(15;17) translocation when complete remission was achieved. ATRA was very well-tolerated. The symptoms of dry skin and intermittent headache were self-limiting.
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Affiliation(s)
- K Wong
- Department of Medical Oncology, Singapore General Hospital
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21
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Visser W, Beckmann I, Bremer HA, Lim HL, Wallenburg HC. Bioactive tumour necrosis factor alpha in pre-eclamptic patients with and without the HELLP syndrome. Br J Obstet Gynaecol 1994; 101:1081-2. [PMID: 7826964 DOI: 10.1111/j.1471-0528.1994.tb13587.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- W Visser
- Department of Obstetrics and Gynaecology, Erasmus University School of Medicine and Health Sciences, The Netherlands
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22
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Davis GL, Lau JY, Lim HL. Therapy for chronic hepatitis C. Gastroenterol Clin North Am 1994; 23:603-13. [PMID: 7527375] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Hepatitis C is the silent epidemic of the 1970s and 1980s. Interferon alfa is currently the only effective treatment. Enthusiasm for interferon therapy must be tempered because advanced disease usually requires years or even decades to develop and does not occur in all patients. Few patients with chronic hepatitis C derive long-term improvement from a single 6-month course of interferon therapy. Most initial responders relapse and require long-term interferon treatment to suppress the virus. Obviously, the initial goals and expectations for interferon therapy require rethinking. Therapy should not be undertaken by physician or patient with the idea that therapy will be limited to 6 months. The most appropriate goal of therapy now appears to be the long-term control of the biochemical, virologic, and histologic activity of the disease. Unfortunately, the most effective therapeutic regimen for achieving this goal is not yet known and will require continued clinical research.
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Affiliation(s)
- G L Davis
- Section of Hepatobiliary Diseases, University of Florida College of Medicine, Gainesville
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Lim HL, Teo CP, Wong K, Kuperan P, Suri R, Tan YO, Kueh YK. Multiple myeloma: the National University Hospital (NUH) experience. Singapore Med J 1994; 35:371-3. [PMID: 7899894] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The aim of this retrospective study was to define the characteristics of local patients with multiple myeloma. Twenty-nine de novo cases were accrued from October 1986 to January 1992 at the National University Hospital of Singapore. Features like median age of presentation, sex distribution, the incidence of IgG, IgA and light chain subtypes were similar to published data. However IgD myeloma appeared to be more common here and it tended to be more advanced at presentation. Objective response rate to treatment with the melphalan-prednisolone combination was about 40% with a median survival of 18 months.
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Affiliation(s)
- H L Lim
- Department of Medicine, National University Hospital, Singapore
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24
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Teo CP, Lim HL, Kueh YK. Cost effectiveness and ease of administration of low molecular weight heparin in deep vein thrombosis. Thromb Haemost 1994; 72:328-9. [PMID: 7831676] [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: 01/27/2023]
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Abstract
A 51-year-old heart transplant recipient who developed subfulminant hepatic failure because of organ-transmitted hepatitis C virus (HCV) infection is described. He presented with a predominantly cholestatic liver damage after heart transplantation. An extensive evaluation, including abdominal ultrasound and computed tomography scan and endoscopic retrograde cholangiopancreatography was unrevealing. Liver biopsy, however, was suggestive of a large duct obstruction with prominent portal and pericellular fibrosis, marked cholestasis, pericholangitis with marked ductular proliferation, and diffuse hepatocyte degeneration. Antibody to HCV (anti-HCV) was initially negative. He deteriorated in the ensuing 3 months. A repeat enzyme immunoassay-2 test for anti-HCV 4 months after initial presentation was weakly positive. Quantitation of serum HCV RNA by branched DNA assay revealed high level viremia, 547 x 10(6) genome equivalents per milliliter. Using in situ polymerase chain reaction, HCV RNA was detected in the cytoplasm in > 80% of the hepatocytes. The patient underwent interferon alfa therapy, and serum HCV RNA levels were reduced 20-fold after four doses. Unfortunately, the patient developed pulmonary aspergillosis and died. This case illustrates that in immunosuppressed patients anti-HCV is not a good marker for the diagnosis of HCV infection, and HCV can cause a progressive form of cholestatic liver disease mimicking a large duct obstruction.
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Affiliation(s)
- H L Lim
- Department of Medicine, University of Florida, Gainesville
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26
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Lim HL, Abbitt PL, Kniffen JC, Myers BM. Hepatic infarction complicating a transjugular intrahepatic portosystemic shunt. Am J Gastroenterol 1993; 88:2095-7. [PMID: 8249979] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Transjugular intrahepatic portocaval shunt (TIPS) is being used with increasing frequency to treat variceal bleeding and portal hypertension. Like any other invasive vascular procedure, it has the potential for serious complications. We report a case of a woman who underwent a TIPS procedure for variceal bleeding due to hepatitis C and sustained a hepatic infarction as a complication of the procedure. We caution about the potential for catastrophic complications with this procedure, and recommend that it be performed only in centers with a liver transplant program nearby.
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Affiliation(s)
- H L Lim
- Division of Gastroenterology, Hepatology, and Nutrition, University of Florida College of Medicine, Gainesville
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Lim HL. A practical approach to the management of depression. Singapore Med J 1993; 34:449-51. [PMID: 8153697] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Depression is a common and treatable condition. Failure to diagnose it may lead to unnecessary investigations, delay in treatment and an increased risk of suicide. Anti-depressant drugs are the first line of treatment. Tricyclics are generally the drugs of choice as their efficacy is very well established. Second generation antidepressant drugs are preferred for the elderly and those with heart disease as they tend to have milder side effects and are less toxic in overdose. Electroconvulsive therapy is indicated in those with severe depression, high suicide risk or failed drug treatment. Psychotherapy is usually used as an adjunct to pharmacotherapy whilst lithium is used to prevent recurrence of depression.
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Affiliation(s)
- H L Lim
- Mt Elizabeth Medical Centre, Singapore
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28
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Tan TK, Teo FC, Wong K, Lim HL. Cancer: To tell or not to tell? Singapore Med J 1993; 34:202-3. [PMID: 8266172] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
After a patient is diagnosed with a malignant illness, the physician is often left with the dilemma of how to communicate the diagnosis to the patient and the family. In the West, it is often the consensus that the patient be told. This is not necessarily true elsewhere, eg in Japan, the patient is often not told. A questionnaire survey was done to study how Singapore doctors feel about revealing the diagnosis of cancer to the patient. 90.4% of respondents will reveal the diagnosis to the family, while only 43.6% will inform the patient. The possible reasons are discussed.
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Affiliation(s)
- T K Tan
- Department of Psychological Medicine, National University Hospital, Singapore
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Tan HC, Lim HL, Lim TK, Chan TB, Chan HL. The toxic strept syndrome: two case reports. Singapore Med J 1992; 33:29-30. [PMID: 1598604] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We describe two patients with group A beta hemolytic streptococcal septicemia from minor foci in the skin. They developed extreme toxemia, mental obtundation and multi-system organ failure associated with diffuse erythema. They both survived after appropriate antibiotic and intense supportive therapy. These are examples of the "toxic strept syndrome" which is similar to staphylococcal toxic shock.
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Affiliation(s)
- H C Tan
- Department of Medicine, National University Hospital, Singapore
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30
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Abstract
The copulatory performance of 18 sexually experienced male rats was tested 30 min after IP injection of the phenylpiperazine, Fluprazine Hydrochloride (4 and 8 mg/kg), or saline solution. Three 20-min tests with an estrous female were conducted at weekly intervals. Each drug dose produced a significant depressive effect on copulatory behavior (latency to and frequency of intromissions and ejaculations) without affecting social investigation. The increased latencies to mounting and intromission observed at both doses suggest that the primary action of the Fluprazine Hydrochloride is to interfere with the transition from social to copulatory patterns. Although the drug's mode of action is currently unknown, the present findings suggest that it operates on some common mediator of sexual and aggressive behavior.
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Lim HL, Costa JL. Systemic sclerosis (scleroderma) with chronic liver disease. Singapore Med J 1972; 13:51-3. [PMID: 5031956] [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: 01/13/2023]
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