1.Minimally Invasive Approach to Supra-pubic and Non-Midline Lower Abdominal Ventral Hernia: An Extended Indication of TAPE Technique.
Joe King Man FAN ; Jeremy YIP ; Matrix FUNG ; Oswens Siu Hung LO ; Jianwen LIU ; Xuefei YANG ; Kejin CHEN ; Wai Lun LAW
Journal of Minimally Invasive Surgery 2017;20(3):84-92
Repair of lower abdominal incisional hernia is always a surgical challenge. TAPE technique has been described for the repair of supra-pubic midline incisional hernia with satisfactory outcome. Its indication can be extended for treatment of non-midline lower abdominal hernia. Peritoneal incision is created just below the hernia defect with pre-peritoneal dissection to expose supra-pubic preperitoneal space with Cooper's ligament exposed. Non-adhesive mesh then placed over preperitoneal space and partially intra-peritoneally, and cover the whole extra-peritoneal space prepared to ensure enough overlapping. Mesh is fixed by tackers for intra-peritoneal part, most inferior fixation points were at peritoneal incision line. Extra-peritoneal part of meshes is fixed at the safety zone and covered up by the peritoneal flap to avoid mesh migration. Fixation of the meshes at the lateral aspects were facilitated by the peritoneal flap and subsequent fibrosis and adhesion to the extra-peritoneal structures in cases of lateral lower abdominal hernia. Repair of midline and lateral lower abdominal incisional hernia with this novel modified technique with prosthetic mesh is safe and effective. A larger case series and longer follow-up is required for validation of this technique.
Fibrosis
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Follow-Up Studies
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Hernia
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Hernia, Abdominal
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Hernia, Ventral*
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Incisional Hernia
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Ligaments
3.Cancer stem-like cells in Epstein-Barr virus-associated nasopharyngeal carcinoma.
Samantha Wei-Man LUN ; Siu-Tim CHEUNG ; Kwok-Wai LO
Chinese Journal of Cancer 2014;33(11):529-538
Although the Epstein-Barr virus (EBV) has spread to all populations in the world, EBV-associated nasopharyngeal carcinoma (NPC) is prevalent only in South China and Southeast Asia. The role of EBV in the malignant transformation of nasopharyngeal epithelium is the main focus of current researches. Radiotherapy and chemoradiotherapy have been successful in treating early stage NPC, but the recurrence rates remain high. Unfortunately, local relapse and metastasis are commonly unresponsive to conventional treatments. These recurrent and metastatic lesions are believed to arise from residual or surviving cells that have the properties of cancer stem cells. These cancer stem-like cells (CSCs) have the ability to self-renew, differentiate, and sustain propagation. They are also chemo-resistant and can form spheres in anchorage-independent environments. This review summarizes recent researches on the CSCs in EBV-associated NPC, including the findings regarding cell surface markers, stem cell-related transcription factors, and various signaling pathways. In particular, the review focuses on the roles of EBV latent genes [latent membrane protein 1 (LMP1) and latent membrane protein 2A (LMP2A)], cellular microRNAs, and adenosine triphosphate (ATP)-binding cassette chemodrug transporters in contributing to the properties of CSCs, including the epithelial-mesenchymal transition, stem-like transition, and chemo-resistance. Novel therapeutics that enhance the efficacy of radiotherapy and chemoradiotherapy and inhibitors that suppress the properties of CSCs are also discussed.
Carcinoma
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Cell Transformation, Neoplastic
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China
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Drug Resistance, Neoplasm
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genetics
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Epithelial-Mesenchymal Transition
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Herpesvirus 4, Human
;
genetics
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Humans
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MicroRNAs
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Multidrug Resistance-Associated Proteins
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Nasopharyngeal Neoplasms
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Nasopharynx
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Neoplasm Metastasis
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Neoplasm Recurrence, Local
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Neoplastic Stem Cells
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Signal Transduction
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Viral Matrix Proteins
4.Epstein-Barr virus infection and persistence in nasopharyngeal epithelial cells.
Chi Man TSANG ; Wen DENG ; Yim Ling YIP ; Mu-Sheng ZENG ; Kwok Wai LO ; Sai Wah TSAO
Chinese Journal of Cancer 2014;33(11):549-555
Epstein-Barr virus (EBV) infection is closely associated with undifferentiated nasopharyngeal carcinoma (NPC), strongly implicating a role for EBV in NPC pathogenesis; conversely, EBV infection is rarely detected in normal nasopharyngeal epithelial tissues. In general, EBV does not show a strong tropism for infecting human epithelial cells, and EBV infection in oropharyngeal epithelial cells is believed to be lytic in nature. To establish life-long infection in humans, EBV has evolved efficient strategies to infect B cells and hijack their cellular machinery for latent infection. Lytic EBV infection in oropharyngeal epithelial cells, though an infrequent event, is believed to be a major source of infectious EBV particles for salivary transmission. The biological events associated with nasopharyngeal epithelial cells are only beginning to be understood with the advancement of EBV infection methods and the availability of nasopharyngeal epithelial cell models for EBV infection studies. EBV infection in human epithelial cells is a highly inefficient process compared to that in B cells, which express the complement receptor type 2 (CR2) to mediate EBV infection. Although receptor(s) on the epithelial cell surface for EBV infection remain(s) to be identified, EBV infection in epithelial cells could be achieved via the interaction of glycoproteins on the viral envelope with surface integrins on epithelial cells, which might trigger membrane fusion to internalize EBV in cells. Normal nasopharyngeal epithelial cells are not permissive for latent EBV infection, and EBV infection in normal nasopharyngeal epithelial cells usually results in growth arrest. However, genetic alterations in premalignant nasopharyngeal epithelial cells, including p16 deletion and cyclin D1 overexpression, could override the growth inhibitory effect of EBV infection to support stable and latent EBV infection in nasopharyngeal epithelial cells. The EBV episome in NPC is clonal in nature, suggesting that NPC develops from a single EBV-infected nasopharyngeal epithelial cell, and the establishment of persistent and latent EBV infection in premalignant nasopharyngeal epithelium may represent an early and critical event for NPC development.
Carcinoma
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Cell Transformation, Neoplastic
;
Cells, Cultured
;
Epithelial Cells
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Epstein-Barr Virus Infections
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Herpesvirus 4, Human
;
Humans
;
Nasopharyngeal Neoplasms
;
Nasopharynx
;
Precancerous Conditions
5.Molecular basis of von Hippel-Lindau syndrome in Chinese patients.
Wai-Kwan SIU ; Ronald Ching-Wan MA ; Ching-Wan LAM ; Chloe Miu MAK ; Yuet-Ping YUEN ; Fai-Man Ivan LO ; Kin-Wah CHAN ; Siu-Fung LAM ; Siu-Cheung LING ; Sui-Fan TONG ; Wing-Yee SO ; Chun-Chung CHOW ; Mary Hoi-Yin TANG ; Wing-Hung TAM ; Albert Yan-Wo CHAN
Chinese Medical Journal 2011;124(2):237-241
BACKGROUNDVon Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.
METHODSNine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).
RESULTSThe nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.
CONCLUSIONSGenetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.
Asian Continental Ancestry Group ; DNA Mutational Analysis ; Humans ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Von Hippel-Lindau Tumor Suppressor Protein ; genetics ; von Hippel-Lindau Disease ; genetics
6.Evaluation of the relationship between cardiac calcification and cardiovascular disease using the echocardiographic calcium score in patients undergoing peritoneal dialysis: a cross-sectional study.
Ho-Kwan SIN ; Ping-Nam WONG ; Kin-Yee LO ; Man-Wai LO ; Shuk-Fan CHAN ; Kwok-Chi LO ; Yuk-Yi WONG ; Lo-Yi HO ; Wing-Tung KWOK ; Kai-Chun CHAN ; Andrew Kui-Man WONG ; Siu-Ka MAK
Singapore medical journal 2023;64(6):379-384
INTRODUCTION:
An echocardiographic calcium score (ECS) predicts cardiovascular disease (CVD) in the general population. Its utility in peritoneal dialysis (PD) patients is unknown.
METHODS:
This cross-sectional study assessed 125 patients on PD. The ECS (range 0-8) was compared between subjects with CVD and those without.
RESULTS:
Among the subjects, 54 had CVD and 71 did not. Subjects with CVD were older (69 years vs. 56 years, P < 0.001) and had a higher prevalence of diabetes mellitus (DM) (81.5% vs. 45.1%, P < 0.001). They had lower diastolic blood pressure (72 mmHg vs. 81 mmHg, P < 0.001), lower phosphate (1.6 mmol/L vs. 1.9 mmol/L, P = 0.002), albumin (30 g/L vs. 32 g/L, P = 0.001), parathyroid hormone (34.4 pmol/L vs. 55.8 pmol/L, P = 0.002), total cholesterol (4.5 vs. 4.9, P = 0.047), LDL cholesterol (2.4 mmol/L vs. 2.8 mmol/L, P = 0.019) and HDL cholesterol (0.8 mmol/L vs. 1.1 mmol/L, P = 0.002). The ECS was found to be higher in subjects with CVD than in those without (2 vs. 1, P = 0.001). On multivariate analysis, only DM and age were independently associated with CVD.
CONCLUSION
The ECS was significantly higher in PD patients with CVD than in those without, reflecting a higher vascular calcification burden in the former. It is a potentially useful tool to quantify vascular calcification in PD patients.
Humans
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Cardiovascular Diseases/diagnostic imaging*
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Cross-Sectional Studies
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Calcium
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Peritoneal Dialysis/adverse effects*
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Vascular Calcification/epidemiology*
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Echocardiography