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Leitao J.,London School of Hygiene and Tropical Medicine | Chandramohan D.,London School of Hygiene and Tropical Medicine | Byass P.,Umea University | Jakob R.,Health Information and Statistics | And 34 more authors.
Global Health Action | Year: 2013

Objective: Verbal autopsy (VA) is a systematic approach for determining causes of death (CoD) in populations without routine medical certification. It has mainly been used in research contexts and involved relatively lengthy interviews. Our objective here is to describe the process used to shorten, simplify, and standardise the VA process to make it feasible for application on a larger scale such as in routine civil registration and vital statistics (CRVS) systems. Methods: A literature review of existing VA instruments was undertaken. The World Health Organization (WHO) then facilitated an international consultation process to review experiences with existing VA instruments, including those from WHO, the Demographic Evaluation of Populations and their Health in Developing Countries (INDEPTH) Network, InterVA, and the Population Health Metrics Research Consortium (PHMRC). In an expert meeting, consideration was given to formulating a workable VA CoD list [with mapping to the International Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) CoD] and to the viability and utility of existing VA interview questions, with a view to undertaking systematic simplification. Findings: A revised VA CoD list was compiled enabling mapping of all ICD-10 CoD onto 62 VA cause categories, chosen on the grounds of public health significance as well as potential for ascertainment from VA. A set of 221 indicators for inclusion in the revised VA instrument was developed on the basis of accumulated experience, with appropriate skip patterns for various population sub-groups. The duration of a VA interview was reduced by about 40% with this new approach. Conclusions: The revised VA instrument resulting from this consultation process is presented here as a means of making it available for widespread use and evaluation. It is envisaged that this will be used in conjunction with automated models for assigning CoD from VA data, rather than involving physicians. © 2013 Jordana Leitao et al. Source

The efficacy of tendon-derived stem cells (TDSCs) for the promotion of tendon and tendon-bone junction repair has been reported in animal studies. Modulation of the tendon stem cell niche in vivo has also been reported to influence tendon structure. There is a need to have specific and reliable markers that can define TDSCs in vitro and tendon stem cells in situ for several reasons: to understand the basic biology of TDSCs and their subpopulations in vitro; to understand the identity, niches and functions of tendon/progenitor stem cells in vivo; to meet the governmental regulatory requirements for quality of TDSCs when translating the exciting preclinical findings into clinical trial/practice; and to develop new treatment strategies for mobilizing endogenous stem/progenitor cells in tendon. TDSCs were reported to express the common mesenchymal stem cell (MSC) markers and some embryonic stem cell (ESC) markers, and there were attempts to use these markers to label tendon stem cells in situ. Are these stem cell markers useful for the identification of TDSCs in vitro and tracking of tendon stem cells in situ? This review aims to discuss the values of the panel of MSC, ESC and tendon-related markers for the identification of TDSCs in vitro. Important factors influencing marker expression by TDSCs are discussed. The usefulness and limitations of the panel of MSC, ESC and tendon-related markers for tracking stem cells in tendon, especially tendon stem cells, in situ are then reviewed. Future research directions are proposed. © 2015 Lui; licensee BioMed Central. Source

Lui P.P.Y.,Headquarter | Lee Y.W.,Chinese University of Hong Kong | Mok T.Y.,Chinese University of Hong Kong | Cheuk Y.C.,Chinese University of Hong Kong
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2015

Purpose: The clinical relevance and mechanisms of local bone loss early post-anterior cruciate ligament (ACL) reconstruction remain unclear. The early spatial and temporal changes of peri-tunnel bone, its molecular mechanisms and its relationships with graft–bone tunnel healing were investigated in a 12-week-old rat model. Methods: At various times, the reconstructed ACL complex was harvested for vivaCT imaging, biomechanical test, histology and immunohistochemical staining of CD68+ cells (a monocyte–macrophage lineage marker), MMP1 and MMP13. Results: The peri-tunnel bone resorbed simultaneously with improvement of graft–bone tunnel healing. There were 30.1 ± 17.4, 46.8 ± 10.5 and 81.5 ± 12.3 % loss of peri-tunnel BMD as well as 43.2 ± 21.7, 78.7 ± 8.5 and 92.4 ± 17.7 % loss of peri-tunnel bone volume/total volume (BV/TV) at week 6 at the distal femur, epiphysis and metaphysis of tibia, respectively. MMP1, MMP13 and CD68+ cells were expressed at the graft–bone tunnel interface and peri-tunnel bone and increased with time post-reconstruction at the tibia. The ultimate load and stiffness of the healing complex positively correlated with tibial tunnel bone formation and negatively correlated with tibial peri-tunnel bone. Tunnel BV/TV at the tibial metaphysis and epiphysis showed the highest correlation with ultimate load (ρ = 0.591; p = 0.001) and stiffness (ρ = 0.427; p = 0.026) of the complex, respectively. Conclusion: There was time-dependent loss of peri-tunnel bone early post-reconstruction, with the greatest loss occurring at the tibial metaphysis. This was consistent with high expression of MMP1, MMP13 and CD68+ cells at the graft–bone tunnel interface and the peri-tunnel region. The significant loss of peri-tunnel bone, though not critically affecting early tunnel healing, suggested the need to protect the knee joint early post-reconstruction. © 2013, Springer-Verlag Berlin Heidelberg. Source

Lui P.P.Y.,Headquarter | Kong S.K.,Chinese University of Hong Kong | Lau P.M.,Chinese University of Hong Kong | Wong Y.M.,Chinese University of Hong Kong | And 3 more authors.
Tissue Engineering - Part A | Year: 2014

The medium-to long-term healing effect and infiltration of inflammatory cells, after transplantation of allogeneic tendon-derived stem cell (TDSC) to the rat patellar tendon window wound, were examined. Allogeneic patellar TDSCs derived from a green fluorescent protein rat were used. The outcome of tendon healing and the infiltration of inflammatory cells were examined by histology and immunohistochemistry up to week 16 postinjury. The fate of the transplanted cells was examined by ex vivo fluorescent imaging and immunohistochemistry. Our results showed that the transplantation of allogeneic TDSCs promoted tendon healing with no increased risk of ectopic chondro-ossification up to week 16. A low infiltration of T cells, ED1 macrophages, ED2 macrophages, and mast cells in the window wound was obtained. The transplanted TDSCs were found in the window wound at week 1 and 2, but were absent after week 4 postinjury. In conclusion, allogeneic TDSCs promoted tendon repair in the medium to long term and exhibited weak immunoreactions and anti-inflammatory effects in the hosts after transplantation in a rat model. There was no increased risk of ectopic chondro-ossification after TDSC transplantation. The decrease in the number of transplanted cells with time suggested that allogeneic TDSCs did not promote tendon repair through direct differentiation. © 2014, Mary Ann Liebert, Inc. Source

Wu M.-H.,A-Life Medical | Chou Y.-C.,National Defense Medical Center | Chou W.-Y.,Fu Jen Catholic University | Hsu G.-C.,Tri Service General Hospital | And 5 more authors.
International Journal of Cancer | Year: 2010

Epidemiological observations suggest that insulin-like growth factor-I (IGF-I), a potent mitogenic and anti-apoptotic peptide, plays a role in the etiology of breast cancer. Estrogen, which is crucial in breast carcinogenesis, both regulates and is influenced by IGF-I family. A case-control study was conducted to assess the role of IGF-I as a biomarker for breast cancer and to evaluate the potential joint effect of circulating IGF-I and critical period of estrogen exposure, as estimated by the interval between age at menarche and age at first full-term pregnancy on the risk of breast cancer. Questionnaire information and blood samples were taken before treatment from 297 incident cases with breast cancer and 593 controls admitted for health examination at the Tri-Service General Hospital, Taipei between 2004 and 2006. Plasma levels of IGF-I and IGFBP-3 were measured by immunoradiometric assay. Conditional logistic regression was used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs). Our case-control data indicate that breast cancer risk related to IGF-I differs according to menopausal status. High circulating levels of IGF-I increased risk of pre- but not postmenopausal breast cancer (top vs. bottom tertile, adjusted OR, 1.86; 95% CI, 1.01-3.44). Furthermore, elevated IGF-I concentrations in conjunction with prolonged interval of critical period of estrogen exposure were associated with significantly increased risk of breast cancer, particularly among estrogen-positive cases (adjusted OR, 2.42, 95% CI, 1.33-4.38). These results suggest that the joint effect of IGF-I and estrogens may provide novel methods of breast cancer risk reduction among women. © 2009 UICC. Source

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