2.Engineering Novel Molecular Beacon Constructs to Study Intracellular RNA Dynamics and Localization
Ma ZHAO ; Wu XIAOTIAN ; Krueger J. CHRISTOPHER ; Chen K. ANTONY
Genomics, Proteomics & Bioinformatics 2017;15(5):279-286
With numerous advancements in novel biochemical techniques, our knowledge of the role of RNAs in the regulation of cellular physiology and pathology has grown significantly over the past several decades. Nevertheless, detailed information regarding RNA processing, trafficking, and localization in living cells has been lacking due to technical limitations in imaging single RNA transcripts in living cells with high spatial and temporal resolution. In this review, we discuss tech-niques that have shown great promise for single RNA imaging, followed by highlights in our recent work in the development of molecular beacons (MBs), a class of nanoscale oligonucleotide-probes, for detecting individual RNA transcripts in living cells. With further refinement of MB design and development of more sophisticated fluorescence microscopy techniques, we envision that MB-based approaches could promote new discoveries of RNA functions and activities.
3.Emerging signals regulating liver tumor initiating cells
Chen JINGYU ; Chen CHIEN-YU ; Nguyen CHRISTOPHER ; Chen LULU ; Lee KANGMIN ; L.Stiles BANGYAN
Liver Research 2018;2(2):73-80
Tumor initiating cells(TICs)have been identified as cells that account for tumor heterogeneity.Recent studies demonstrated that genes controlling stem cell biology play key roles in maintaining TICs and promote their development into cancer.In this review,we summarize findings from human and animal studies that indicate the presence of TICs during liver cancer development.Markers identified for liver development and regeneration are used to identify liver cancer TICs.Expression of these markers is often upregulated in human hepatocellular carcinoma(HCC)specimen.Using flow cytometry analysis and lineage tracing approaches,the presence of TICs is confirmed.Expression of TIC markers and the pres-ence of TICs are also observed in genetically modified animals that target genes that are frequently altered in human HCC.The presence of these TICs represents a major challenge for therapeutic devel-opment.Elucidating signals that can regulate the fate,transformation and growth of liver TICs is an emerging need in liver research.Sex-determining region Y-box 9(SOX9)has recently become an important marker for liver TICs.Here,we summarize the role of SOX9 in TICs and its potential interaction with other signals.This includes the Notch-Numb signal that controls asymmetrical-symmetrical cell division,Wnt-β-catenin signal that maintains cell fate and transforming growth factor(TGF)-β signal that acts as upstream inducers.
4.Limb-shaking transient ischemic attack with distal micro-embolic signals and impaired cerebrovascular reactivity using transcranial Doppler.
Deidre Anne De SILVA ; Moi-Pin LEE ; Meng-Cheong WONG ; Hui-Meng CHANG ; Christopher L H CHEN
Annals of the Academy of Medicine, Singapore 2008;37(7):619-620
Carotid Artery, Internal
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diagnostic imaging
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Cerebrovascular Disorders
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diagnostic imaging
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physiopathology
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Extremities
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physiopathology
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Humans
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Ischemic Attack, Transient
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complications
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diagnostic imaging
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drug therapy
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Male
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Middle Aged
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Middle Cerebral Artery
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diagnostic imaging
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Thromboembolism
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diagnostic imaging
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physiopathology
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Ultrasonography, Doppler, Transcranial
5.Timing of hospital presentation after acute cerebral infarction and patients' acceptance of intravenous thrombolysis.
Deidre Anne De SILVA ; Sea-Hing ONG ; Danny ELUMBRA ; Meng-Cheong WONG ; Christopher L H CHEN ; Hui-Meng CHANG
Annals of the Academy of Medicine, Singapore 2007;36(4):244-246
INTRODUCTIONIntravenous thrombolysis has been shown to improve outcome after acute cerebral infarction if given within 3 hours of symptom onset. There are no data in Singapore on the timing of hospital presentation after acute cerebral infarction as well as factors and reasons for delayed presentation.
MATERIALS AND METHODSAs intravenous thrombolysis has recently been licensed for use in acute cerebral infarction in Singapore, we studied 100 consecutive acute cerebral infarction admitted to the Singapore General Hospital for timing of hospital presentation, reasons associated with delay in presentation and hypothetical acceptance of intravenous thrombolysis.
RESULTSOnly 9% of patients presented to hospital within 2 hours of symptom onset. Factors associated with hospital presentation within 2 hours were a large stroke and lack of pre-hospital consultation. Failure to recognise the severity of symptoms and inability to seek medical attention unaided were the 2 most common reasons for delayed presentation. One-third of patients or their relatives hypothetically would accept intravenous thrombolysis, suggesting that a thrombolysis service is feasible at the Singapore General Hospital. However, it would be hindered by the low proportion of patients who present early to hospital after symptom onset.
CONCLUSIONOur results support the need for a public education programme to highlight the identification of stroke symptoms and the need to present to hospital as soon as possible after the onset of stroke symptoms.
Acute Disease ; Aged ; Cerebral Infarction ; drug therapy ; physiopathology ; Emergency Service, Hospital ; Female ; Fibrinolytic Agents ; therapeutic use ; Hospitals, General ; Humans ; Infusions, Intravenous ; Male ; Middle Aged ; Patient Acceptance of Health Care ; statistics & numerical data ; Prospective Studies ; Singapore ; Time Factors ; Treatment Outcome
6.Computer-assisted design of therapeutic personalized footwear for diabetic foot:a preliminary study
Xu WANG ; Xin MA ; Lijie MA ; Li CHEN ; Chao ZHANG ; Jiazhang HUANG ; Xiangjie GU ; Jianyu JIANG ; Dongmei WANG ; Chengtao WANG ; Kai TAO ; James CHRISTOPHER ; Williams ANITA ; Liu ANMIN
Chinese Journal of Orthopaedics 2011;31(5):514-519
Objective To explore the outcomes of computer-assisted design of therapeutic personalized footwear for diabetic foot.Methods Fifty-eight cases of diabetic foot were included in the study.Ten items of data from theses patients were measured with methods provided by Salford University.All characteristics of the footwear were calculated with computer.Shoes were specially designed with the formula and computational method provided by Safford university.All patients had worn the shoes for 13 months.Special questionnaires were used to measure the outcomes.Results Thirty-two cases had been followed up for one month,25 cases for 2 months,25 cases for 3 months and 42 cases for 13 months.The score had improved from 67.94±15.14 before wearing the shoes to 78.13±1.44 thirteen months after wearing.The health score of the foot had improved.There was significant difference between before and after wearing the footwears.Conclusion Special-designed diabetic shoes play an important role in the prevention of ulcer for diabetic foot patients.Computational method and data model obtained from Salford university needs to be modified when applying it for Chinese.
7.Changes in main causes of death in Macao residents from 1986 - 2006.
Man-si CHAN ; Qing CHEN ; Christopher Wai-kei LAM
Chinese Medical Journal 2013;126(9):1661-1666
BACKGROUNDSince Macao's return of sovereignty to China in December 1999, the life style of Macao residents has changed. The aim of this study was to investigate changes of death patterns in Macao residents from 1986 to 2006 in order to identify the trends and patterns of major public health problems, which could provide the guidance for developing public health policies.
METHODSA retrospective study was conducted for this investigation. Research data were collected from official websites and statistical yearbooks and classified by the International Classification of Diseases (ICD)-9.
RESULTSIt was observed that mortality from the three major causes of (1) infectious, maternal and childhood diseases, (2) chronic non-communicable diseases, and (3) injury and poisoning were 17.7, 298.2 and 26.0 per 100 000, respectively. The largest decrease in death rate over the 21-year study-period was from infectious, maternal and childhood diseases (62.5%). The highest mortality rate was ischemic heart diseases (37.0%). The largest increase in mortality rate was lung cancer (46.9%).
CONCLUSIONSMortality rate of Macao residents progressively decreased, but the constituent ratio of death from chronic non-communicable diseases was increasing. The mortality rate of lung cancer was clearly ascending, so emphasis should be put on tertiary prevention in future.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Cause of Death ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Infant, Newborn ; Macau ; epidemiology ; Male ; Middle Aged ; Neoplasms ; mortality ; Primary Health Care ; Retrospective Studies ; Time Factors
8.Prevalence and Awareness of Lower Urinary Tract Symptoms among Males in the Outpatient Clinics of Universiti Kebangsaan Malaysia Medical Centre
Christopher Ho CK ; Praveen S ; Goh EH ; Tan GH ; Badrulhisham B ; Zulkifli MZ ; Khoo HW ; Su XV ; Ng JY ; Chong LL ; Lim DW ; Chen ES ; Teoh SY
Medicine and Health 2011;6(2):98-106
This study aims to determine the prevalence of lower urinary tract symptoms (LUTS) and level of awareness among male outpatients in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). A questionnaire consisting of demographic data, questions related to knowledge, attitude and practice on BPH and the International Prostate Symptom Score (IPSS) was used for this study. Uroflowmetry and bladder scan were used to evaluate the function of the urinary tract and severity of BPH. Urine dipstick was done for glycosuria, proteinuria and haematuria. A total of 220 respondents were surveyed. The prevalence of moderately and severely symptomatic LUTS was 42.7%. The most commonly reported LUTS were nocturia (78.2%), frequency (58.2%) and incomplete emptying (44.6%). The prevalence of glycosuria, proteinuria and haematuria were 23.6%, 11.4% and 1.8% respectively. There was a significant association between increasing age with the severity of LUTS (p=0.005). Out of 102 respondents with voided urine volume greater than 150 mL, there was a significant decrease in maximum (Qmax) (p=0.039) and average (Qave) urine flow rates with every 10 years increase of age (p=0.001). The majority of respondents (59.5%) have heard of BPH before. Over 78.2% of the respondents would seek medical attention if they have LUTS with 15.9% saying they would seek traditional treatment. In conclusion, the prevalence of LUTS was high and the level of awareness was satisfactory.
9.Potential Use of Transferred Lymph Nodes as Metastasis Detectors after Tumor Excision.
Fabio NICOLI ; Pedro CIUDAD ; Seong Yoon LIM ; Davide LAZZERI ; Christopher D'AMBROSIA ; Kidakorn KIRANANTAWAT ; Ram M CHILGAR ; Stamatis SAPOUNTZIS ; Bulent SACAK ; Hung Chi CHEN
Archives of Plastic Surgery 2015;42(4):478-483
Due to the fact that it reliably results in positive outcomes, lymph node flap transfer is becoming an increasingly popular surgical procedure for the prevention and treatment of lymphedema. This technique has been shown to stimulate lymphoangiogenesis and restore lymphatic function, as well as decreasing infection rates, minimizing pain, and preventing the recurrence of lymphedema. In this article, we investigate possible additional benefits of lymph node flap transfer, primarily the possibility that sentinel lymph nodes may be used to detect micro-metastasis or in-transit metastasis and may function as an additional lymphatic station after the excision of advanced skin cancer.
Carcinogenesis
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Free Tissue Flaps
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Lymph Nodes*
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Lymphedema
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Melanoma
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Neoplasm Metastasis*
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Recurrence
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Skin Neoplasms
10.Clinics in diagnostic imaging (191). Multiple system atrophy-cerebellar type (MSA-C).
Mark Christopher PEARCE ; Garry CHOY ; Robert Chun CHEN
Singapore medical journal 2018;59(10):550-554
A 49-year-old Chinese man was evaluated for progressive uncoordinated movements, dysphagia and urinary symptoms. Magnetic resonance imaging demonstrated a cruciform pattern of T2-weighted hyperintensity within the pons and selective atrophy of the cerebellar hemispheres and pons. The clinical history and radiological findings were consistent with a diagnosis of multiple system atrophy-cerebellar type. This article discussed the background, proposed mechanisms, diagnosis, radiological characteristics, prognosis and management of multiple system atrophy-cerebellar type.