Rural Educational NGOs and Urban Aspirations: Lessons on Skill Planning in Cambodia

This thesis investigates how rural-urban inequality manifests in the decision-­making of a migrant. It revisits the structural role of education in facilitating rural-­urban migration – ‘the modern sector has also been characterized by an urban, industrial bias and a need for a new set of specialized occupational skills. Educational systems responded quickly to these modern sector needs, focusing curricula on modern-­sector educational requirements and strengthening urban schools more quickly than those in rural areas.’ (Edwards & Todaro 1974: 28). In particular, it focuses on whether and how a biased set of ‘specialized occupational skills’ are recognized in individual aspirations, as well as the implications of non-­state rural education within. While contemporary education often stress aspiration as an individualized exploration, this thesis re-­emphasizes it as a reflection of state preference. The findings originate from my work in a rural educational NGO in villages of Takeo, Cambodia. While migration has been widely studied in many other disciplines, the action-­oriented agenda and the emphasis on positioning rural educational NGOs make this a relevant planning issue. With household interviews as well as ethnographic observation and participation, I build narratives of individual aspirations from three villages in Takeo. Through comparing people's aspirations and capabilities to migrate, and understanding the local context of these villages, I make recommendations for development actors of an equity-­driven mind, state and non-state agencies, and researchers in current Cambodia

Identifying mosaic genetic variants in tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is an autosomal dominant condition caused by pathogenic variants in the TSC1 or TSC2 gene with a prevalence of 8.8 per 100 000. TSC is associated with variable neurodevelopmental outcomes, seizures and benign tumours in various organs. Around 10-15% have no pathogenic variants identified – the “no mutations identified” (NMI) cohort. Previously, this cohort were reported to be phenotypically milder and have mosaic/intronic variants. Many have reproductive concerns, but options are not open to them without a molecular diagnosis. This study aims to determine the phenotype of an Australian NMI cohort, and if testing multiple samples of an individual would allow for an improved diagnostic yield using a testing strategy that may be viable in a diagnostic laboratory. The first study discussed the phenotype of the NMI cohort in the Sydney Children’s Hospital TSC management clinic, a tertiary referral centre. A medical records review was used to compare the clinical picture of those in the NMI, heterozygous, and mosaic cohorts. This showed that although those in the NMI cohort likely have a milder neurodevelopmental outcome, they are no different to the heterozygous cohort when considering the number of organ systems involved. This differs from the previous literature. The second study explored the use of multiple samples in deep sequencing of the NMI cohort. Massively parallel sequencing (MPS) using a custom target capture panel consisting of the whole genomic region of TSC1 and TSC2 was performed. A minimum of 2 samples was tested for each participant, including affected tissue where possible. Sequencing occurred with a target read depth of 500x initially and proceeded to 4000x for those who remained persistently NMI. A diagnostic yield of 72% was achieved in the probands tested, with the majority being mosaic variants and the remainder missed heterozygous variants. The use of multiple samples allowed for validation of otherwise discarded low-level mosaic variants. In conclusion, this thesis explored the phenotype and genotype of the NMI cohort. It showed that those in this cohort may not be as mild as previously suggested. Testing multiple samples allows for detection of germline mosaic variants on MPS without excessive cost and the need for specialised techniques. Scaling this up to diagnostic testing is likely viable, which would ultimately be critical for optimal clinical care of the NMI cohort

Robert Black College, University of Hong Kong, 1967-1988: a publication in commemoration of the 21st anniversary of the College

Mainly English, some Chinese.published_or_final_versio

Genetic study of congenital bile-duct dilatation identifies de novo and inherited variants in functionally related genes

Background: Congenital dilatation of the bile-duct (CDD) is a rare, mostly sporadic, disorder that results in bile retention with severe associated complications. CDD affects mainly Asians. To our knowledge, no genetic study has ever been conducted. Methods: We aim to identify genetic risk factors by a “trio-based” exome-sequencing approach, whereby 31 CDD probands and their unaffected parents were exome-sequenced. Seven-hundred controls from the local population were used to detect gene-sets significantly enriched with rare variants in CDD patients. Results: Twenty-one predicted damaging de novo variants (DNVs; 4 protein truncating and 17 missense) were identified in several evolutionarily constrained genes (p < 0.01). Six genes carrying DNVs were associated with human developmental disorders involving epithelial, connective or bone morphologies (PXDN, RTEL1, ANKRD11, MAP2K1, CYLD, ACAN) and four linked with cholangio- and hepatocellular carcinomas (PIK3CA, TLN1 CYLD, MAP2K1). Importantly, CDD patients have an excess of DNVs in cancer-related genes (p < 0.025). Thirteen genes were recurrently mutated at different sites, forming compound heterozygotes or functionally related complexes within patients. Conclusions: Our data supports a strong genetic basis for CDD and show that CDD is not only genetically heterogeneous but also non-monogenic, requiring mutations in more than one genes for the disease to develop. The data is consistent with the rarity and sporadic presentation of CDD

Osteoprotective effects of Fructus Ligustri Lucidi aqueous extract in aged ovariectomized rats

<p>Abstract</p> <p>Background</p> <p><it>Fructus Ligustri Lucidi </it>(FLL) is a commonly used herb for treating bone disorders in Chinese medicine. The present study investigates the anti-osteoporotic activity of FLL aqueous extract in the model of postmenopausal bone loss in aged ovariectomized (OVX) female rats.</p> <p>Methods</p> <p>After eight weeks of treatment of FLL or water, the lumbar spine was scanned by peripheral quantitative computed tomography (pQCT). Effects of FLL water extract on osteogenic and adipogenic differentiations in rat mesenchymal stem cells (MSCs) were assessed by biochemical methods and staining.</p> <p>Results</p> <p>FLL aqueous extract significantly inhibited bone mineral density (BMD) loss in total, trabecular and cortical bones without affecting body weight and uterus wet weight. FLL extract significantly promoted osteogenesis and suppressed adipogenesis in MSCs as indicated by the elevated alkaline phosphatase activity, calcium deposition levels and decreased adipocyte number in a dose-dependent manner without cytotoxic effects. Real-time PCR analysis revealed significant increase of osteoprotegerin (OPG)-to-receptor activator for nuclear factor-κB ligand (RANKL) mRNA, indicating a decrease in osteoclastogenesis.</p> <p>Conclusion</p> <p>The present study demonstrates the osteoprotective effects of FLL aqueous extract on aged OVX rats, stimulation of osteogenesis, inhibition of adipogenesis and osteoclastogenesis in MSCs.</p

Targeted next-generation sequencing on hirschsprung disease: A pilot study exploits DNA pooling

To adopt an efficient approach of identifying rare variants possibly related to Hirschsprung disease (HSCR), a pilot study was set up to evaluate the performance of a newly designed protocol for next generation targeted resquencing. In total, 20 Chinese HSCR patients and 20 Chinese sex-matched individuals with no HSCR were included, for which coding sequences (CDS) of 62 genes known to be in signaling pathways relevant to enteric nervous system development were selected for capture and sequencing. Blood DNAs from eight pools of five cases or controls were enriched by PCR-based RainDance technology (RDT) and then sequenced on a 454 FLX platform. As technical validation, five patients from case Pool-3 were also independently enriched by RDT, indexed with barcode and sequenced with sufficient coverage. Assessment for CDS single nucleotide variants showed DNA pooling performed well (specificity/sensitivity at 98.4%/83.7%) at the common variant level; but relatively worse (specificity/sensitivity at 65.5%/61.3%) at the rare variant level. Further Sanger sequencing only validated five out of 12 rare damaging variants likely involved in HSCR. Hence more improvement at variant detection and sequencing technology is needed to realize the potential of DNA pooling for large-scale resequencing projects. © 2014 John Wiley & Sons Ltd/University College London.postprin

Ensuring quality in 17OHP mass spectrometry measurement:an international study assessing isomeric steroid interference

Objectives: Interference from isomeric steroids is a potential cause of disparity between mass spectrometry-based 17-hydroxyprogesterone (17OHP) results. We aimed to assess the proficiency of mass spectrometry laboratories to report 17OHP in the presence of known isomeric steroids. Methods:A series of five samples were prepared using a previously demonstrated commutable approach. These samples included a control (spiked to 15.0 nmol/L 17OHP) and four challenge samples further enriched with equimolar concentrations of 17OHP isomers (11α-hydroxyprogesterone, 11β-hydroxyprogesterone, 16α-hydroxyprogesterone or 21-hydroxyprogesterone). These samples were distributed to 38 participating laboratories that reported serum 17OHP results using mass spectrometry in two external quality assurance programs. The result for each challenge sample was compared to the control sample submitted by each participant. Results: Twenty-six laboratories (68 % of distribution) across three continents returned results. Twenty-five laboratories used liquid chromatography-tandem mass spectrometry (LC-MS/MS), and one used gas chromatography-tandem mass spectrometry to measure 17OHP. The all-method median of the control sample was 14.3 nmol/L, ranging from 12.4 to 17.6 nmol/L. One laboratory had results that approached the lower limit of tolerance (minus 17.7 % of the control sample), suggesting the isomeric steroid caused an irregular result. Conclusions: Most participating laboratories demonstrated their ability to reliably measure 17OHP in the presence of the four clinically relevant isomeric steroids. The performance of the 12 (32 %) laboratories that did not engage in this activity remains unclear. We recommend that all laboratories offering LC-MS/MS analysis of 17OHP in serum, plasma, or dried bloodspots determine that the isomeric steroids are appropriately separated.</p