386 research outputs found
Kruppel-like factor 4 suppresses neuroblastoma growth by promoting smooth-muscle differentiation
Poster Board Number: 2105Neuroblastoma (NB) is an embryonic tumor and possesses a unique propensity to exhibit either a spontaneous regression or an unrestrained growth. Growing evidence suggests that NB comprises heterogeneous populations of improperly differentiated neural crest cells and a small subset of NB cells behaves as stem cells. Commitment of NB stem cells to the fibromuscular lineage may give a favorable outcome, while to the neuronal lineage results in a malignant tumor progression. Kruppel like factor 4 (KLF4) is one of the key reprogramming factors. Intriguingly, it also possesses paradoxical functions in cancers, either as an oncogene or tumor suppressor dependent of cell context. In this study, we elucidated the roles of KLF4 in the lineage determination of NB stem cells and tumor progression. Quantitative RT-PCR showed that loss of KLF4 expression ...published_or_final_versio
School health partnership in service learning : a Hong Kong experience
Version of RecordPublishe
Seguimiento de las obras hidráulicas de desagüe pluvial de la Región Capital-Evaluación hidrológica e hidráulica
En este informe de avance trimestral se describen las tareas de gabinete y campo desarrolladas entre agosto y octubre de 2016, correspondientes a la evaluación hidrológica e hidráulica de las obras de mejora del sistema pluvial en ejecución.
Se abordan en forma preliminar los siguientes temas:
- Grado de protección que brindan las obras en construcción
- Plan de trabajo de las obras en ejecución
- Evaluación del tramo Papelera - Empalme del conducto de calle 11
- Estudio de los reservorios de la cuenca alta.Este informe técnico fue presentado en una Reunión técnica de la Comisión Bicameral llevada a cabo en el Salón Directorio de la CIC el 1 de noviembre de 201
Correction of Hirschsprung-Associated Mutations in Human Induced Pluripotent Stem Cells Via Clustered Regularly Interspaced Short Palindromic Repeats/Cas9, Restores Neural Crest Cell Function
ACKGROUND & AIMS: Hirschsprung disease is caused by failure of enteric neural crest cells (ENCCs) to fully colonize the bowel, leading to bowel obstruction and megacolon. Heterozygous mutations in the coding region of the RET gene cause a severe form of Hirschsprung disease (total colonic aganglionosis). However, 80% of HSCR patients have short-segment Hirschsprung disease (S-HSCR), which has not been associated with genetic factors. We sought to identify mutations associated with S-HSCR, and used the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 gene editing system to determine how mutations affect ENCC function. METHODS: We created induced pluripotent stem cell (iPSC) lines from 1 patient with total colonic aganglionosis (with the G731del mutation in RET) and from 2 patients with S-HSCR (without a RET mutation), as well as RET+/- and RET-/- iPSCs. IMR90-iPSC cells were used as the control cell line. Migration and differentiation capacities of iPSC-derived ENCCs were analyzed in differentiation and migration assays. We searched for mutation(s) associated with S-HSCR by combining genetic and transcriptome data from patient blood- and iPSC-derived ENCCs, respectively. Mutations in the iPSCs were corrected using the CRISPR/Cas9 system. RESULTS: ENCCs derived from all iPSC lines, but not control iPSCs, had defects in migration and neuronal lineage differentiation. RET mutations were associated with differentiation and migration defects of ENCCs in vitro. Genetic and transcriptome analyses associated a mutation in the vinculin gene (VCL M209L) with S-HSCR. CRISPR/Cas9 correction of the RET G731del and VCL M209L mutations in iPSCs restored the differentiation and migration capacities of ENCCs. CONCLUSIONS: We identified mutations in VCL associated with S-HSCR. Correction of this mutation in iPSC using CRISPR/Cas9 editing, as well as the RET G731del mutation that causes Hirschsprung disease with total colonic aganglionosis, restored ENCC function. Our study demonstrates how human iPSCs can be used to identify disease-associated mutations and determine how they affect cell functions and contribute to pathogenesis.postprin
Using illness scripts to teach clinical reasoning skills to medical students
Background and Objectives: Most medical students learn clinical reasoning skills informally during clinical rotations that have varying quality of supervision. We conducted a randomized controlled trial to determine if a workshop that uses "illness scripts" could improve students' clinical reasoning skills when making diagnoses of patients portrayed in written scenarios. Methods: In 2007-2008, 53 fourth-year medical students were randomly assigned to either a family medicine (intervention) or psychiatry (control) clerkship at The Chinese University of Hong Kong. Students in the intervention group participated in a 3-hour workshop on clinical reasoning that used illness scripts. The workshop was conducted with small-group teaching using a Web-based set of clinical reasoning problems, individualized feedback, and demonstration of tutors' reasoning aloud. The effectiveness of the intervention was assessed using the Diagnostic Thinking Inventory (DTI) and the measurement of individual students' performance in solving clinical reasoning problems (CRP). Results: The postintervention overall DTI scores between groups were similar (mean difference 0, 95% confidence interval [CI]= -7.4 to 7.4). However, the total scores on the CRP assessment were 14% (95% CI=8% to 21%) higher in the intervention group than in controls. Conclusion: A workshop on illness scripts may have some benefit for improving diagnostic performance in clinical reasoning problems.link_to_OA_fulltex
Vicarious Group Trauma among British Jews
This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s11133-016-9337-4Given that literature on the intra- and inter-generational transmission of traumas is mainly based on secondary literature and focuses on the transmission of trauma memory in terms of the historical knowledge of group trauma, this article develops the theory of vicarious group trauma and tests this theory by exploring vicarious traumatization in the everyday lives of Jews in Britain through the methods of observation and in-depth interviewing. Vicarious group trauma is defined as a life or safety-threatening event or abuse that happened to some members of a social group but is felt by other members as their own experience because of their personal affiliation with the group. The article finds that the vicarious sensation of traumatic group experiences can create anxiety, elicit perceptions of threat and, by extension, hypervigilance among Jews. The findings demonstrate that group traumas of the past interpenetrate and interweave with members’ current lives and in this way can also become constitutive of their group identity. An institutional focus on threats to Jews can inform the construction and reinforcement of traumatization symptoms and accordingly vicarious group trauma. This article suggests an association between the level of involvement of group members in the collective’s social structure and the prominence of vicarious group trauma among them
Tracking people across disjoint camera views
University of Technology, Sydney. Faculty of Information Technology.Tracking people around surveillance systems is becoming increasingly
important in the current security conscious environment. This thesis presents
a framework to automatically track the movements of individual people in
large video camera networks, even where there are gaps between camera
views. It is designed to assist security operators, or police investigations by
providing additional information about the location of individuals throughout
the surveillance area. Footage from an existing surveillance system has
been used to test the framework under real conditions. The framework uses
the similarity of robust shape and appearance features to match tracks. These
features are extracted to build an object feature model as people move within
a single camera view, which can be compared across cameras. The integration
of matching similarities in the temporal domain increases the robustness
to errors of many kinds. Frames with significant segmentation errors can be
automatically detected and removed based upon their lack of similarity to
the other models within the same track, increasing robustness.
The shape and appearance features used to generate the object models
are based upon features humans habitually use for identifying individuals.
They include a height estimate, a Major Colour Representation (MCR) of
the individuals global colours, and estimates of the colours of the upper
and lower portions of clothing. The fusion of these features is shown to
be complementary, providing increased discrimination between individuals.
The MCR colour features are improved through the mitigation of illumination
changes using controlled equalisation, which improves the accuracy
in matching colour under normal surveillance conditions and requires no
training or scene knowledge. The incorporation of other features into this
framework is also relatively straightforward.
This track matching framework was tested upon four individuals across
two video cameras of an existing surveillance system. Existing infrastructure
and actors were used to ensure that ground truth is available. Specific
cases were constructed to test the limitations of the system when similar
clothing is worn. In the data, the height difference ranges from 5 to 30
centimetres, and individuals may only be wearing 50% of similar clothing
colours. The accuracy of matching an individual was as high as 91% with
only 5% false alarms when all the system components were used. This may
not become a fully automated system, but could be used in semi-automated
or human assisted systems, or as the basis for further research into improved
automated surveillance. Application areas range from forensic surveillance
to the matching of the movements of key individuals throughout a surveillance
network and possibly even target location
Temporal evolution of soot particles from C2H2/O-2 combustion in a closed chamber
An experimental study of soot formation in C2H2/O-2 flames at different C/O ratios in a closed chamber was carried out. The evolution temporal behavior and the volume fraction of soot particles were determined by laser extinction. It was found that total time for the soot formation phenomenon in flames from C2H2/O-2 with C/O ratio >0.75 or C2H2/O-2/Ar with C/O ratio = 1.00 was around 3.0-4.0 ms after ignition. At almost the same time the excited radicals reached their maximum emission intensity and the gases under combustion reached their maximum pressure. The micrographs show compact and approximately spherical soot particles with diameters within 60-150 nm. However, soot aggregates are not compact and they present a netlike structure similar to that of an aerogel.131475
Synchronized partial-body motion graphs
Author name used in this publication: William W. L. NGAuthor name used in this publication: Clifford S. T. ChoyAuthor name used in this publication: Daniel P. K. LunRefereed conference paper2010-2011 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe
Greater variability in lipid measurements associated with kidney diseases in patients with type 2 diabetes mellitus in a 10-year diabetes cohort study.
This study aimed to evaluate the associations between variability of lipid parameters and the risk of kidney disease in patients with type 2 diabetes mellitus. Low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were specifically addressed in this study. This retrospective cohort study included 105,552 patients aged 45-84 with type 2 diabetes mellitus and normal kidney function who were managed under Hong Kong public primary care clinics during 2008-2012. Those with kidney disease (estimated glomerular filtration rate < 60 mL/min/1.73 m2 or urine albumin to creatinine ratio ≥ 3 mg/mmol) were excluded. Variabilities of low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were determined using the standard deviation of the respective parameter obtained from a mixed effects model to minimize regression dilution bias. The associations between lipid variability and renal outcomes including incident kidney disease, renal function decline defined as ≥ 30% reduction in estimated glomerular filtration rate since baseline, and end-stage renal disease (estimated glomerular filtration rate < 15 mL/min/1.73 m2) were evaluated by multivariable Cox regression. After a median follow-up of 66.5 months (0.5 million person-years in total), 49,653 kidney disease, 29,358 renal function decline, and 1765 end-stage renal disease cases were recorded. Positive linear associations between low-density lipoprotein-cholesterol and total cholesterol to high-density lipoprotein-cholesterol ratio variabilities and the risk of all renal outcomes were demonstrated. However, no association between triglyceride variability and any outcome was found. Each mmol/L increase in low-density lipoprotein-cholesterol variability was associated with 20% (Hazard ratio 1.20 [95% CI 1.15-1.25]), 38% (Hazard ratio 1.37 [95% CI 1.30-1.45]), and 108% (Hazard ratio 2.08 [95% CI 1.74-2.50]) higher risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Similarly, each unit increase in total cholesterol to high-density lipoprotein-cholesterol ratio variability was associated with 35% (Hazard ratio 1.15 [95% CI 1.10-1.20]), 33% (Hazard ratio 1.33 [95% CI 1.26-1.40]), and 75% (Hazard ratio 1.75 [95% CI 1.46-2.09]) heightened risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Cholesterol variability may potentially be a useful predictor of kidney diseases in patients with type 2 diabetes mellitus. Attention should be drawn to cholesterol variability when managing diabetic patients and further research is warranted to investigate the modifiable risk factors for lipid variability
- …
