1.Prevalence of Disaccharidase Deficiency in Adults With Unexplained Gastrointestinal Symptoms
Lavanya VISWANATHAN ; Satish S C RAO ; Kevin KENNEDY ; Amol SHARMA ; Yun YAN ; Enoe JIMENEZ
Journal of Neurogastroenterology and Motility 2020;26(3):384-390
Background/Aims:
Disaccharidase assay is used for assessing carbohydrate intolerance in children, but its usefulness in adults is not known. The aim of this study is to assess the prevalence of disaccharidase deficiency in patients with unexplained gastrointestinal symptoms.
Methods:
A retrospective review of adults with chronic (> 1 year) abdominal symptoms and negative imaging and endoscopy/colonoscopy and who completed bowel symptom questionnaire and duodenal biopsy for lactase, maltase, sucrase, and palatinase was performed. A subset also underwent 25 g lactose breath test (LBT).
Results:
One hundred twenty patients (females = 83) were evaluated, of whom 48 also underwent LBT. Fifty-six (46.7%) patients had enzyme deficiency; 44 (36.7%) had single (either lactase or maltase), 1 had 3 enzyme deficiencies, 11 (9.2 %) had all 4 disaccharidase enzyme (pan-disaccharidase) deficiency, and 64 (53.0%) had normal enzyme levels. Baseline prevalence and severity of 11 gastrointestinal symptoms were similar between normal and single enzyme deficiency groups. The sensitivity and specificity of LBT was 78.3% and 72.0%, respectively and overall agreement with lactase deficiency was 75.0%.
Conclusions
Isolated disaccharidase deficiency occurs in adults, usually lactase and rarely maltase, and pan-disaccharidase deficiency is rare. Baseline symptoms or its severity did not predict enzyme deficiency.
2.Prospective randomized trial comparing efficacy and safety of intravenous and intra-articular tranexamic acid in total knee arthroplasty
Moses Man-Lung LI ; Jojo Yan-Yan KWOK ; Kwong-Yin CHUNG ; Kin-Wing CHEUNG ; Kwok-Hing CHIU ; Wai-Wang CHAU ; Kevin Ki-Wai HO
The Journal of Korean Knee Society 2020;32(4):e62-
Background:
Total knee arthroplasty (TKA) is associated with significant perioperative blood loss and postoperative allogenic blood transfusion. Tranexamic acid (TXA) reversibly blocks lysine binding sites on plasminogen molecules and inhibits plasmin formation. Comparisons of the efficacy and safety of intra-articular and intravenous TXA in primary TKA have not previously been reported.
Methods:
A prospective randomized trial was conducted in 150 patients who underwent TKA, and these patients were randomized into three groups. Patients in Group A were injected by intra-articular TXA according to body weight (20 mg/kg). Patients in Group B received a standard dose of intra-articular TXA (2000 mg), and those in Group C were infused with TXA according to body weight (20 mg/kg) before tourniquet deflation and again 3 h later. Baseline characteristics and data collected at blood transfusion were compared. Differences among four time points (baseline, day 0, day 2, and day 5) were carried out using ANOVA.
Results:
The hemoglobin levels at postoperative day 5 were 10.6 g/dL for Group A, 10.6 g/dL for Group B, and 10.7 g/dL for Group C. The drain output was 399 ml for Group A, 314 ml for Group B, and 305 ml for Group C (p = 0.03). Group C had significantly less drain output than Group A after post hoc comparisons (p = 0.05), whereas no significant difference was observed between Group A and B (p = 0.09) or between Group B and C.
Conclusion
The weight-adjusted dose of TXA administered intravenously significantly reduced the drain output but not the total blood loss when compared with the weight-adjusted dose of TXA administered intra-articularly. No significant difference was observed in the other parameters among the three groups.Trial registrationThe Joint CUHK-NTEC CREC, CRE-2013.644-T. Registered 1 March 2014.
3.Prospective randomized trial comparing efficacy and safety of intravenous and intra-articular tranexamic acid in total knee arthroplasty
Moses Man-Lung LI ; Jojo Yan-Yan KWOK ; Kwong-Yin CHUNG ; Kin-Wing CHEUNG ; Kwok-Hing CHIU ; Wai-Wang CHAU ; Kevin Ki-Wai HO
The Journal of Korean Knee Society 2020;32(4):e62-
Background:
Total knee arthroplasty (TKA) is associated with significant perioperative blood loss and postoperative allogenic blood transfusion. Tranexamic acid (TXA) reversibly blocks lysine binding sites on plasminogen molecules and inhibits plasmin formation. Comparisons of the efficacy and safety of intra-articular and intravenous TXA in primary TKA have not previously been reported.
Methods:
A prospective randomized trial was conducted in 150 patients who underwent TKA, and these patients were randomized into three groups. Patients in Group A were injected by intra-articular TXA according to body weight (20 mg/kg). Patients in Group B received a standard dose of intra-articular TXA (2000 mg), and those in Group C were infused with TXA according to body weight (20 mg/kg) before tourniquet deflation and again 3 h later. Baseline characteristics and data collected at blood transfusion were compared. Differences among four time points (baseline, day 0, day 2, and day 5) were carried out using ANOVA.
Results:
The hemoglobin levels at postoperative day 5 were 10.6 g/dL for Group A, 10.6 g/dL for Group B, and 10.7 g/dL for Group C. The drain output was 399 ml for Group A, 314 ml for Group B, and 305 ml for Group C (p = 0.03). Group C had significantly less drain output than Group A after post hoc comparisons (p = 0.05), whereas no significant difference was observed between Group A and B (p = 0.09) or between Group B and C.
Conclusion
The weight-adjusted dose of TXA administered intravenously significantly reduced the drain output but not the total blood loss when compared with the weight-adjusted dose of TXA administered intra-articularly. No significant difference was observed in the other parameters among the three groups.Trial registrationThe Joint CUHK-NTEC CREC, CRE-2013.644-T. Registered 1 March 2014.
4.Proliferation and apoptosis property of mesenchymal stem cells derived from peripheral blood under the culture conditions of hypoxia and serum deprivation.
Wei-Li FU ; Zhu-Qing JIA ; Wei-Ping WANG ; Ji-Ying ZHANG ; Xin FU ; Xiao-Ning DUAN ; Kevin Kar Ming LEUNG ; Chun-Yan ZHOU ; Jia-Kuo YU
Chinese Medical Journal 2011;124(23):3959-3967
BACKGROUNDThe proliferation and apoptosis property of mesenchymal stem cells derived from peripheral blood (PB-MSCs) were investigated under hypoxia and serum deprivation conditions in vitro so as to evaluate the feasibility for autologous PB-MSCs applications in cartilage repair.
METHODSMSCs were mobilized into peripheral blood by granulocyte colony stimulating factor (G-CSF) and AMD3100. The blood samples were collected from central ear artery of rabbits. Adhered cells were obtained by erythrocyte lysis buffer and identified as MSCs by adherence to plastic, spindle shaped morphology, specific surface markers, differentiation abilities into osteoblasts, adipocytes and chondroblasts in vitro under appropriate conditions. MSCs were cultured in four groups at different oxygen tension (20% O2 and 2% O2), with or without 10% fetal bovine serum (FBS) conditions: 20% O2 and 10% FBS complete medium (normal medium, N), 20% O2 and serum deprivation medium (D), 2% O2 and 10% FBS complete medium (hypoxia, H), 2% O2 and serum deprivation (HD). Cell proliferation was determined by CCK-8 assay. Apoptosis was detected by Annexin V/PI and terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL) staining.
RESULTSSpindle-shaped adherent cells were effectively mobilized from peripheral blood by a combined administration of G-CSF plus AMD3100. These cells showed typical fibroblast-like phenotype similar to MSCs from bone marrow (BM-MSCs), and expressed a high level of typical MSCs markers CD29 and CD44, but lacked in the expression of hematopoietic markers CD45 and major histocompatibility complex Class II (MHC II). They could also differentiate into osteoblasts, adipocytes and chondroblasts in vitro under appropriate conditions. No significant morphological differences were found among the four groups. It was found that hypoxia could enhance proliferation of PB-MSCs regardless of serum concentration, but serum deprivation inhibited proliferation at the later stage of culture. Apart from that, hypoxia or serum deprivation could promote the apoptosis of PB-MSCs after 48 hours; the effect was stronger when these two conditions combined together. Furthermore, the effect of serum deprivation on apoptosis was stronger compared with that of hypoxia.
CONCLUSIONSPB-MSCs possess similar phenotypes as BM-MSCs. Their differentiation and proliferation abilities make them a new source of seed cells for ischemia-related cell therapy and tissue engineering in the field of the articular cartilage repair.
Animals ; Apoptosis ; physiology ; Cell Hypoxia ; physiology ; Cell Proliferation ; Cells, Cultured ; In Situ Nick-End Labeling ; Mesenchymal Stromal Cells ; cytology ; Rabbits
5.Statin-centric versus low-density lipoprotein-centric approach for atherosclerotic cardiovascular disease prevention: a Singapore perspective.
Peter YAN ; Eng Kiat Kevin TAN ; Jason Chon Jun CHOO ; Choon Fong Stanley LIEW ; Titus LAU ; David D WATERS
Singapore medical journal 2016;57(7):360-367
The link between cholesterol levels and atherosclerotic cardiovascular disease (ASCVD) is well-established. In Singapore, there is an increasing prevalence of risk factors for ASCVD. Like many Asian countries, Singapore's population is rapidly ageing and increasingly sedentary, which predisposes individuals to chronic health problems. Current international and local guidelines recommend statin therapy for the primary and secondary prevention of ASCVD. However, despite the effectiveness of statin therapy, some studies have highlighted that Asian patients with cardiovascular disease are not achieving target lipid goals. Furthermore, it is widely believed that the responses of Asians (both patients and physicians) to statin therapy are different from those of their Western counterparts. Experts convened in 2014 to determine the impact of current guidelines on clinical practice in Singapore. This review summarises the key findings and recommendations of these guidelines, and presents key principles to aid clinicians to manage the cardiovascular risk of their patients more effectively.
Aging
;
Atherosclerosis
;
drug therapy
;
Cardiology
;
standards
;
Cardiovascular Diseases
;
drug therapy
;
Humans
;
Hydroxymethylglutaryl-CoA Reductase Inhibitors
;
therapeutic use
;
Life Style
;
Lipoproteins, LDL
;
blood
;
Practice Guidelines as Topic
;
Risk Assessment
;
Risk Factors
;
Singapore
6.Nucleus-targeted Dmp1 transgene fails to rescue dental defects in Dmp1 null mice.
Shu-Xian LIN ; Qi ZHANG ; Hua ZHANG ; Kevin YAN ; Leanne WARD ; Yong-Bo LU ; Jian-Quan FENG
International Journal of Oral Science 2014;6(3):133-141
Dentin matrix protein 1 (DMP1) is essential to odontogenesis. Its mutations in human subjects lead to dental problems such as dental deformities, hypomineralization and periodontal impairment. Primarily, DMP1 is considered as an extracellular matrix protein that promotes hydroxyapatite formation and activates intracellular signaling pathway via interacting with αvβ3 integrin. Recent in vitro studies suggested that DMP1 might also act as a transcription factor. In this study, we examined whether full-length DMP1 could function as a transcription factor in the nucleus and regulate odontogenesis in vivo. We first demonstrated that a patient with the DMP1 M1V mutation, which presumably causes a loss of the secretory DMP1 but does not affect the nuclear translocation of DMP1, shows a typical rachitic tooth defect. Furthermore, we generated transgenic mice expressing (NLS)DMP1, in which the endoplasmic reticulum (ER) entry signal sequence of DMP1 was replaced by a nuclear localization signal (NLS) sequence, under the control of a 3.6 kb rat type I collagen promoter plus a 1.6 kb intron 1. We then crossbred the (NLS)DMP1 transgenic mice with Dmp1 null mice to express the (NLS)DMP1 in Dmp1-deficient genetic background. Although immunohistochemistry demonstrated that (NLS)DMP1 was localized in the nuclei of the preodontoblasts and odontoblasts, the histological, morphological and biochemical analyses showed that it failed to rescue the dental and periodontal defects as well as the delayed tooth eruption in Dmp1 null mice. These data suggest that the full-length DMP1 plays no apparent role in the nucleus during odontogenesis.
Animals
;
Cell Nucleus
;
genetics
;
Codon, Initiator
;
genetics
;
Collagen Type I
;
genetics
;
Endoplasmic Reticulum
;
genetics
;
Extracellular Matrix Proteins
;
genetics
;
Familial Hypophosphatemic Rickets
;
genetics
;
Gene Targeting
;
methods
;
Genetic Vectors
;
genetics
;
Humans
;
Introns
;
genetics
;
Methionine
;
genetics
;
Mice, Inbred C57BL
;
Mice, Transgenic
;
Mutation
;
genetics
;
Odontoblasts
;
cytology
;
Odontogenesis
;
genetics
;
Periodontal Diseases
;
genetics
;
Periodontal Ligament
;
pathology
;
Phosphoproteins
;
genetics
;
Promoter Regions, Genetic
;
genetics
;
Tooth Abnormalities
;
genetics
;
Tooth Eruption
;
genetics
;
Transcription Factors
;
genetics
;
Transgenes
;
genetics
;
Valine
;
genetics
;
Young Adult