1.Observation of dendritic cell morphology under light, phase-contrast or confocal laser scanning microscopy.
Tan, Yuen-Fen ; Leong, Chooi-Fun ; Cheong, Soon-Keng
The Malaysian Journal of Pathology 2010;32(2):97-102
Dendritic cells (DCs) are professional antigen presenting cells of the immune system. They can be generated in vitro from peripheral blood monocytes supplemented with GM-CSF, IL-4 and TNF alpha. During induction, DCs will increase in size and acquire multiple cytoplasmic projections when compared to their precursor cells such as monocytes or haematopoietic stem cells which are usually round or spherical. Morphology of DCs can be visualized by conventional light microscopy after staining or phase-contrast inverted microscopy or confocal laser scanning microscopy. In this report, we described the morphological appearances of DCs captured using the above-mentioned techniques. We found that confocal laser scanning microscopy yielded DCs images with greater details but the operating cost for such a technique is high. On the other hand, the images obtained through light microscopy after appropriate staining or phase contrast microscopy were acceptable for identification purpose. Besides, these equipments are readily available in most laboratories and the cost of operation is affordable. Nevertheless, morphological identification is just one of the methods to characterise DCs. Other methods such as phenotypic expression markers and mixed leukocyte reactions are additional tools used in the characterisation of DCs.
Dendritic Cells/*cytology
;
Microscopy, Confocal
;
Microscopy, Phase-Contrast
2.Is research related to a country’s economic development? An analysis of biomedical publications from several GCC and ASEAN countries from 1994-2013
Chao Tian Tang ; Paul Mark Wilkerson ; Yuen Soon
The Medical Journal of Malaysia 2016;71(2):57-61
Introduction: Biomedical research has traditionally been the
domain of developed countries. We aim to study the effects
of the increased focus on biomedical and medical research
on level 1-4 publications in several industrialised and newly
industrialised countries endowed with petroleum and gas
resources.
Methods: We identified all level 1-4 publications from
01/01/1994 to 31/12/2013 via PubMed using advanced
options. The population and GDP (current US$) data from
1994-2013 were obtained through data provided by the
World Bank and the raw data was normalised based on
these two indicators.
Results: From 1994-2013, Saudi Arabia and Malaysia were
responsible for the highest absolute number of level 1 to 4
biomedical and medical research publications with 2551 and
1951 publications respectively. When normalised to
population, Kuwait and Qatar had the highest publication
rates, with 7.84 and 3.99 publications per 100,000
inhabitants respectively in a five yearly average. Kuwait
produced the largest number of publications per billion
(current US$) of GDP, at 2.92 publications, followed by
Malaysia at 2.82 publications in a five yearly average.
Conclusion: The population size of a country as well as GDP
can influence the number of level 1-4 publications in some
countries. More importantly, effective government policy
which stimulates research as well as a culture which actively
promotes research as shown by Malaysia have proven to
have a larger influence on the amount of level 1-4 biomedical
and medical publications.
Biomedical Research
3.Experimental production of clinical-grade dendritic cell vaccine for acute myeloid leukemia.
Yuen-Fen Tan ; Geok-Choo Sim ; Aziz Habsah ; Chooi-Fun Leong ; Soon-Keng Cheong
The Malaysian journal of pathology 2008;30(2):73-9
Dendritic cells (DC) are professional antigen presenting cells of the immune system. Through the use of DC vaccines (DC after exposure to tumour antigens), cryopreserved in single-use aliquots, an attractive and novel immunotherapeutic strategy is available as an option for treatment. In this paper we describe an in vitro attempt to scale-up production of clinical-grade DC vaccines from leukemic cells. Blast cells of two relapsed AML patients were harvested for DC generation in serum-free culture medium containing clinical-grade cytokines GM-CSF, IL-4 and TNF-alpha. Cells from patient 1 were cultured in a bag and those from patient 2 were cultured in a flask. The numbers of seeding cells were 2.24 x 10(8) and 0.8 x 10(8), respectively. DC yields were 10 x 10(6) and 29.8 x 10(6) cells, giving a conversion rate of 4.7% and 37%, respectively. These DC vaccines were then cryopreserved in approximately one million cells per vial with 20% fresh frozen group AB plasma and 10% DMSO. At 12 months and 21 months post cryopreservation, these DC vaccines were thawed, and their sterility, viability, phenotype and functionality were studied. DC vaccines remained sterile up to 21 months of storage. Viability of the cryopreserved DC in the culture bag and flask was found to be 50% and 70% at 12 months post cryopreservation respectively; and 48% and 67% at 21 months post cryopreservation respectively. These DC vaccines exhibited mature DC surface phenotypic markers of CD83, CD86 and HLA-DR, and negative for haemopoietic markers. Mixed lymphocyte reaction (MLR) study showed functional DC vaccines. These experiments demonstrated that it is possible to produce clinical-grade DC vaccines in vitro from blast cells of leukemic patients, which could be cryopreserved up to 21 months for use if repeated vaccinations are required in the course of therapy.
Vaccines
;
month
;
Grade
;
Clinical
;
Lower case ecks
4.Head and neck cancers masquerading as deep neck abscesses.
Sue Rene SOON ; Jeevendra KANAGALINGAM ; Shirish JOHARI ; Heng Wai YUEN
Singapore medical journal 2012;53(12):840-842
Deep neck space abscesses are common otolaryngological emergencies, and prompt incision and drainage is the treatment of choice. Head and neck cancers often present with cervical metastases that may become secondarily infected. Clinical presentation is similar to a deep neck abscess. Surgical drainage of such collections has implications on subsequent treatment. In this case series, we describe six cases with this unusual presentation that were subsequently found to have a head and neck malignancy, and where three patients had their abscesses treated surgically. We aim to raise awareness of this unusual presentation of a head and neck carcinoma, and to avoid a potential pitfall in the management of deep neck abscess.
Abscess
;
diagnosis
;
Adult
;
Biopsy
;
Carcinoma, Squamous Cell
;
diagnosis
;
therapy
;
Combined Modality Therapy
;
Diagnosis, Differential
;
Female
;
Head and Neck Neoplasms
;
diagnosis
;
therapy
;
Humans
;
Male
;
Middle Aged
;
Neck
;
Tomography, X-Ray Computed
5.A case series of complicated infective otitis media requiring surgery in adults.
Harold HEAH ; Sue Rene SOON ; Heng-Wai YUEN
Singapore medical journal 2016;57(12):681-685
INTRODUCTIONWith the advent of antibiotics, complications of otitis media have become less common. It is crucial for physicians to recognise otitis media and treat its complications early. Herein, we present our institution's experience with patients who required emergency surgical intervention for complications of otitis media.
METHODSData on patients who underwent emergency surgery for complications of otitis media from 2004 to 2011 was retrieved from the archives of the Department of Otolaryngology, Changi General Hospital, Singapore.
RESULTSA total of 12 patients (10 male, two female) underwent emergency surgery for complications of otitis media. The median age of the patients was 25 years. Otalgia, otorrhoea, headache and fever were the main presenting symptoms. Extracranial complications were observed in 11 patients, and six patients had associated intracranial complications. The primary otologic disease was acute otitis media in six patients, chronic otitis media without cholesteatoma in three patients and chronic otitis media with cholesteatoma in three patients. Mastoidectomy and drainage of abscess through the mastoid, with insertion of grommet tube, was the main surgical approach. Two patients required craniotomy. The mean length of hospital stay was 16.2 days and the mean follow-up period was 16.3 months. Five patients had residual conductive hearing loss; two patients with facial palsy had full recovery.
CONCLUSIONOtitis media can still result in serious complications in the post-antibiotic era. Patients with otitis media should be monitored, and prompt surgical intervention should be performed when necessary to attain good outcomes.
Adult ; Audiometry ; Chronic Disease ; Facial Paralysis ; complications ; Female ; Fever ; complications ; Hospitals ; Humans ; Length of Stay ; Male ; Middle Aged ; Otitis Media ; complications ; diagnostic imaging ; surgery ; Retrospective Studies ; Singapore ; Treatment Outcome ; Young Adult
6.A Case of Synchronous Primary Triple Cancers Including Stomach, Esophagus and Liver.
Do Hyun KIM ; Eun Woo LEE ; Dong Goo KANG ; Youn Ah KIM ; Hyuck PARK ; Myung Weon KANG ; Yuen Keun LIM ; Hyang Soon YEO ; Kyung Soo KIM
Korean Journal of Gastrointestinal Endoscopy 2000;21(4):797-801
Multiple primary malignant cancer is a disease of more than two cancers occuring in an individual independently. The incidence of multiple primary malignant cancer is increasing gradually due to accurate cancer statistics, early diagnosis and treatment. Multiple primary malignant cancer may be divided into two groups, synchronous or metachronous depending on the interval between their diagnoses. Synchronous cancer is diagnosed simultaneously or within an interval of 6 months and metachronous cancer at interval of more than 6 months. Here, we report a case of synchronous primary triple cancers including stomach, esophagus and liver. The patient was a 63-year-old man with dysphagia. We performed endoscopy, chest and abdominal CT. We found cancers in stomach, esophagus and liver and confirmed triple primary cancer through endoscopic biopsy and sono-guided liver biopsy.
Biopsy
;
Deglutition Disorders
;
Diagnosis
;
Early Diagnosis
;
Endoscopy
;
Esophagus*
;
Humans
;
Incidence
;
Liver*
;
Middle Aged
;
Stomach*
;
Thorax
;
Tomography, X-Ray Computed
7.Asia's first successful minimally invasive transapical transcatheter mitral valve-in-valve implantation.
Jia Lin SOON ; Yeow Leng CHUA ; Victor Tt CHAO ; Paul Tl CHIAM ; See Hooi EWE ; Ving Yuen SEETHO ; Chung Yin LEE ; Swee Yaw TAN ; Tian Hai KOH ; Kenny Yk SIN
Annals of the Academy of Medicine, Singapore 2013;42(2):85-87
8.A Case of Endoscopic Treatment of Multiple Carcinoid Tumors in Stomach.
Sang Wook CHO ; Jun Ki KIM ; Seong Ha SHIN ; Young Chun GO ; Jeong Young CHOI ; Myung Weon KANG ; Yuen Keun LIM ; Hyang Soon YEO ; Kyung Soo KIM
Korean Journal of Gastrointestinal Endoscopy 2001;22(1):36-40
Multiple carcinoid tumors in stomach are very rare tumors and associated with pernicious anemia, chronic atrophic gastritis and Zollinger-Ellison syndrome. These are believed to be due to hypergastrinemia, resulting in chronic stimulation of enterochromaffine-like (ECL) cells, leading to hyperplasia, metaplasia and ultimately neoplasia. The carcinoid tumor is potentially malignant, even though it may grow slowly, so the treatment of choice must be endoscopic lumpectomy or surgical gastrectomy. The prognosis depends on the site of the tumor and its size. Most carcinoid tumors are less than 1 cm in size and metastasis is uncommon but metastasis in tumors with size over 2 cm is common. A case of multiple carcinoid tumors in stomach, which was successfully removed by endoscopy, is herein reported.
Anemia, Pernicious
;
Carcinoid Tumor*
;
Endoscopy
;
Gastrectomy
;
Gastrins
;
Gastritis, Atrophic
;
Hyperplasia
;
Mastectomy, Segmental
;
Metaplasia
;
Neoplasm Metastasis
;
Prognosis
;
Stomach*
;
Zollinger-Ellison Syndrome
9.Frequently asked questions in allergy practice
Xiang Xuan TAN ; Peiting XIE ; Jia Li KWEK ; Sock Yuen KWEK ; Zihui YANG ; Weiling SOON ; Jern Lin LEONG ; De Yun WANG
Asia Pacific Allergy 2014;4(1):48-53
BACKGROUND: Over the last 10-20 years, international guidelines and consensus statements for the management of common allergic diseases (e.g. allergic rhinitis and asthma) have been developed and disseminated worldwide. However, their impact on knowledge and standard of clinical practice among primary care physicians and specialists is unknown. OBJECTIVE: To investigate need for an improvement in the dissemination of international guidelines for the diagnosis and management of allergic rhinitis. METHODS: Seven medical students who attended 3-day 1st International Basic Allergy Course (2010) took down all questions raised during the entire course. A systemic analysis of these questions was performed to identify areas for improvement in diagnosis and management of allergic diseases mainly in the Association of Southeast Asian Nations (ASEAN) region. RESULTS: 268 participants, 143 males and 125 females, comprising Ear, Nose and Throat (ENT) specialists (n = 106) and trainees (n = 34), general practitioners (n = 87), and other healthcare professionals (n = 41) attended the course. Of the 103 questions recorded, 59 were regarding treatment modalities in allergy practice such as immunotherapy (n = 38), pharmacologics (n = 15), nasal surgery (n = 2), and others (n = 4). 41 questions (39.8%) have answers based in the Allergic Rhinitis and its Impact on Asthma guidelines (2001 and 2008). Certain questions were selected for further analysis because they appeared to be (a) more commonly asked (e.g. immunotherapy) or (b) were deemed to be challenging or, even controversial (e.g. food allergy and differential diagnosis between vasovagal and anaphylaxis reaction), as the recommendations in current international guidelines were less well-defined. CONCLUSION: Our study identified several problems that, if tackled, could help minimize confusion and provide better care for patients suffering from allergic diseases especially in the ASEAN region.
Anaphylaxis
;
Asian Continental Ancestry Group
;
Asthma
;
Consensus
;
Delivery of Health Care
;
Diagnosis
;
Diagnosis, Differential
;
Ear
;
Female
;
Food Hypersensitivity
;
General Practitioners
;
Humans
;
Hypersensitivity
;
Immunotherapy
;
Male
;
Nasal Surgical Procedures
;
Nose
;
Pharynx
;
Physicians, Primary Care
;
Rhinitis, Allergic
;
Specialization
;
Students, Medical
10.Safety, tolerability and efficacy of LEGA-Kid® mechanical percussion device versus conventional chest physiotherapy in children: a randomised, single-blind controlled study.
Yuen Ling HUE ; Lucy Chai See LUM ; Siti Hawa AHMAD ; Soon Sin TAN ; Shin Yee WONG ; Anna Marie NATHAN ; Kah Peng EG ; Melissa de Bruyne Ming May CHOON
Singapore medical journal 2022;63(2):105-110
INTRODUCTION:
Chest physiotherapy (CPT) may benefit children aged below five years who suffer from lower respiratory tract infection (LRTI). However, its effects depend on the technique used. This study aimed to determine whether mechanical CPT using the LEGA-Kid® mechanical percussion device is superior to manual CPT in children with LRTI.
METHODS:
Children aged five months to five years who were admitted and referred for CPT from January to April 2017 were randomised to either manual CPT or mechanical CPT with LEGA-Kid. Outcomes measured before intervention and two hours after intervention were respiratory rate (RR), oxygen saturation and modified Respiratory Distress Assessment Instrument (mRDAI) score.
RESULTS:
All 30 enrolled patients showed significant reduction in post-intervention RR and mRDAI scores. There was an 8% reduction in RR for the manual CPT group (p = 0.002) and a 16.5% reduction in the mechanical CPT group (p = 0.0001), with a significantly greater reduction in the latter (p = 0.024). mRDAI scores decreased by 2.96 in the manual group (p = 0.0001) and 3.62 in the mechanical group (p = 0.002), with no significant difference between the groups. There was no significant improvement in oxygen saturation, and no adverse events were observed after CPT.
CONCLUSION
Children receiving both manual and mechanical CPT showed improvements in respiratory distress symptoms, with no adverse effects. A combined strategy of nebulised hypertonic saline followed by CPT for LRTI removes airway secretions and results in improvements in moderately severe respiratory distress. The LEGA-Kid mechanical CPT method is superior to manual CPT in reducing the RR.
Child
;
Humans
;
Percussion/methods*
;
Physical Therapy Modalities
;
Respiratory Distress Syndrome
;
Respiratory Therapy/methods*
;
Respiratory Tract Infections
;
Single-Blind Method