MMP14 regulates the lineage progression of hypertrophic chondrocytes

It is traditionally believed that chondrocytes and osteoblasts are two separate lineages with hypertrophic chondrocytes (HCs) being the terminal stage of chondrocyte differentiation, culminating in apoptosis. However, we have shown that HCs can contribute to the full osteoblast (Obs) lineage in vivo. MMP14 is a transmembrane matrix metalloproteinase responsible for matrix remodeling that is highly expressed at the chondro‐osseous junction which coincides with the transition from HCs to Obs. Knockout of Mmp14 in mice results in impaired endochondral ossification. To test whether loss of MMP14 has an impact on the HC to Obs transition, we have employed a genetic recombination approach to track and compare the fate of HCs in wild‐type and Mmp14 conditional and total null mutants. Both complete and conditional deletion of MMP14 activity results in increased number of HC‐descendent cells in the trabecular bone. Surprisingly, conditional knockout of Mmp14 in HC‐descendent cells results in increased trabecular bone formation. Our results suggest that MMP14 in general negatively regulates HC to Obs transition.postprin

The developmental roles of the extracellular matrix: Beyond structure to regulation

Cells in multicellular organisms are surrounded by a complex three-dimensional macromolecular extracellular matrix (ECM). This matrix, traditionally thought to serve a structural function providing support and strength to cells within tissues, is increasingly being recognized as having pleiotropic effects in development and growth. Elucidation of the role that the ECM plays in developmental processes has been significantly advanced by studying the phenotypic and developmental consequences of specific genetic alterations of ECM components in the mouse. These studies have revealed the enormous contribution of the ECM to the regulation of key processes in morphogenesis and organogenesis, such as cell adhesion, proliferation, specification, migration, survival, and differentiation. The ECM interacts with signaling molecules and morphogens thereby modulating their activities. This review considers these advances in our understanding of the function of ECM proteins during development, extending beyond their structural capacity, to embrace their new roles in intercellula signaling. © 2009 Springer-Verlag.postprin

Uncoupled endochondral ossification in transgenic mice expressing type X collagen with mutations in the NC1 domain

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A systematic review and meta-analysis evaluating completeness and outcomes of robotic thyroidectomy

OBJECTIVES/HYPOTHESIS: Despite immense interest, robotic-assisted thyroidectomy (RT) remains controversial in differentiated thyroid carcinoma (DTC). This systematic review and meta-analysis compared surgical completeness and/or oncological outcomes between RT and open thyroidectomy (OT) in low-risk DTC. STUDY DESIGN: Systematic review. METHODS: A systematic review was performed to identify studies that compared surgical completeness and/or oncological outcomes between RT and OT in DTC. Any study that compared at least one parameter relating to surgical completeness and/or oncological outcome for DTC was considered. Number of central lymph nodes (CLNs) retrieved during central neck dissection (CND), preablation stimulated thyroglobulin (sTg) level, radioiodine uptake on post-therapy scan, and locoregional recurrence (LRR) were examined. Meta-analysis was performed using a fixed or random-effects model depending on heterogeneity between studies. RESULTS: Ten studies were eligible. Of the 2,205 DTCs, 752 (34.1%) had RT, whereas 1,453 (65.9%) had OT. Relative to OT, RT had signif icantly fewer CLNs retrieved during CND (4.7 ± 3.2 vs. 5.5 ± 3.8, standardized mean difference [SMD] = -0.240, 95% confidence interval [CI]: -0.364 to -0.116, P < .001) and higher preablation sTg level (3.6 ± 6.7 ng/mL vs. 2.0 ± 5.0 ng/mL, SMD = 0.272, 95% CI: 0.022 to 0.522, P = .033). Interestingly, these differences were more evident in the robotic transaxillary approach (RTAA) than the robotic bilateral axillo-breast approach. After a mean follow-up of 17.7 months, no LRR was found in RT, whereas after 18.6 months, one LRR was found in OT. CONCLUSIONS: Relative to OT, total thyroidectomy by RTAA was associated with fewer CLNs retrieved and less-complete thyroid resection. However, using RTAA is unlikely to compromise the outcomes of low-risk DTC because of its inherently good prognosis. Laryngoscope, 125:509-518, 2015. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.postprin

An evaluative study on the effectiveness of a parent-child parallel group model

Objective; To examine the effectiveness of a parent-child parallel group model that attempted to reduce parent-adolescent conflict. Method: A single group research design with pretest, posttest, and follow-up assessments was employed. Results: Results showed that the level of mother-adolescent conflict at posttest was lower than the level at pretest. The findings, based on the target problem rating, indicated that after the group intervention, both the mothers and adolescents perceived that the problems they had identified in the mother-child relationship had become less severe. The findings, based on subjective outcome measures, were also positive. Conclusion: The present study provides some evidence to support the effectiveness of the parallel group intervention for social work practice.preprin

The relationship between sputum microbial load and leucocyte count in stable bronchiectasis

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Clinical predictors of sputum microbiology in chronic Chinese bronchiectasis

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A unique strain of Escherichia coli O157:H7 that produces low verocytotoxin levels not detected by use of a commercial enzyme immunoassay kit

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Proceedings of The First Current Topic in Infectious Diseases: Consensus Meeting on Conjugate Vaccines of the Center of Infection

Titles include: 1. Invasive Haemophilus Influenzae b Disease: Overview and Disease Burden in Hong Kong (YL LAU) ; 2. Overview and Disease Burden of Haemophilus Influenzae Type b in China (YH YANG) ; 3. Factors to Consider in the Routine Use of Hib in Hong Kong (THF TSANG) ; 4. Burden of Pneumococcal Disease in Hong Kong (CB CHOW) ; 5. Overview and Disease Burden of Streptococcus Pneumoniae in China (YH YANG) ; 6. Resistance in Pediatric Isolates of Pneumococci. Results from a Territorywide Carriage Study (SSS CHIU) ; 7. Serotype Distribution of Invasive and Noninvasive Strains of Pneumococci in Hong Kong (PL HO) ; 8. Overview of Conjugate Pneumococcal Vaccine: Serotype Coverage, Efficacy and Status of Usage in other Countries (SSY WONG)Conference Theme: The First Current Topic in Infectious Diseasespublished_or_final_versio

Digital evidence search kit

With the rapid development of electronic commerce and Internet technology, cyber crimes have become more and more common. There is a great need for automated software systems that can assist law enforcement agencies in cyber crime evidence collection. This paper describes a cyber crime evidence collection tool called DESK (Digital Evidence Search Kit), which is the product of several years of cumulative efforts of our Center together with the Hong Kong Police Force and several other law enforcement agencies of the Hong Kong Special Administrative Region. We will use DESK to illustrate some of the desirable features of an effective cyber crime evidence collection tool. © 2005 IEEE.published_or_final_versio