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991.
Surface engineering approaches that alter the topological chemistry of a substrate could be used as an effective tool for directing cell interactions and their subsequent function. It is well known that the physical environment of nanotopography has positive effects on cell behavior, yet direct comparisons of nanotopographic surface chemistry have not been fully explored. Here we compare TiO(2) nanotubes with carbon-coated TiO(2) nanotubes, probing osteogenic cell behavior, including osteoblast (bone cells) and mesenchymal stem cell (MSC) (osteo-progenitor cells) interactions with the different surface chemistries (TiO(2) vs. carbon). The roles played by the material surface chemistry of the nanotubes did not have an effect on the adhesion, growth or morphology, but had a major influence on the alkaline phosphatase (ALP) activity of osteoblast cells, with the original TiO(2) chemistry having higher ALP levels. In addition, the different chemistries caused different levels of osteogenic differentiation in MSCs; however, it was the carbon-coated TiO(2) nanotubes that had the greater advantage, with higher levels of osteo-differentiation. It was observed in this study that: (a) chemistry plays a role in cell functionality, such as ALP activity and osteogenic protein gene expression (PCR); (b) different cell types may have different chemical preferences for optimal function. The ability to optimize cell behavior using surface chemistry factors has a profound effect on both orthopedic and tissue engineering in general. This study aims to highlight the importance of the chemistry of the carrier material in osteogenic tissue engineering schemes. 相似文献
992.
Méndez-Sánchez N Ponciano-Rodriguez G Chávez-Tapia NC Motola-Kuba D Almeda-Valdes P Sánchez-Lara K Ramos MH Uribe M 《Digestive diseases and sciences》2005,50(4):733-737
Hepatitis C virus (HCV) infection has an estimated prevalence of 3% around the world. Unfortunately, many persons with HCV infection are asymptomatic. The aim of this study was to determine the prevalence of hepatitis C Virus infection in asymptomatic persons. This study was carried out in a population-based cross-sectional study in the Checkup Unit of University Hospital in Mexico City. Patients with two or more HCV risk factors were studied. Serum specimens from all patients were screened for HCV RNA by qualitative polymerase chain reaction (PCR). HCV RNA-positive serum was also screened by quantitative PCR and for HCV genotype. Three hundred asymptomatic people were included, 194 men and 106 women, with a mean age of 46.8 ± 11.9. Six (2%) of the 300 people were positive and viremic. The most common risk factors in positive patients were manicures or pedicures with a nonpersonal instrument and more than three sexual partners. We concluded that hepatitis C is frequent in asymptomatic people, and those people are often viremic. In addition, this study suggests that the spectrum of liver disease in asymptomatic and newly diagnosed HCV-positive persons is broad. 相似文献
993.
Rajatileka S Black WC Saavedra-Rodriguez K Trongtokit Y Apiwathnasorn C McCall PJ Ranson H 《Acta tropica》2008,108(1):54-57
Dengue fever and its more serious complications dengue haemorrhagic fever and dengue shock syndrome are growing public health problems in tropical and subtropical countries. In the absence of a vaccine, most dengue control programmes rely heavily on the use of insecticides to target the Aedes mosquito vectors. As a limited number of insecticides are routinely used in control, monitoring for the presence of resistance is an essential component of dengue prevention programmes. The pyrethroid insecticides target the voltage-gated sodium channel on the insects’ neurons. Substitutions at residue 1016 of this protein have been associated with pyrethroid and DDT resistance in Aedes aegypti populations from Latin America and Asia. Here we report on the development of a simple colorimetric assay to detect these mutations in individual mosquitoes. Evaluation of this diagnostic assay on 180 Ae. aegypti individuals from Thailand revealed the presence of high frequencies of the Val1016Gly mutation throughout the country. The assay requires no specialised equipment and will enable monitoring for insecticide resistance associated alleles to be routinely incorporated into dengue surveillance operations. 相似文献
994.
995.
Mark Chaffin Debra Hecht Greg Aarons Danielle Fettes Michael Hurlburt Karla Ledesma 《Administration and policy in mental health》2016,43(2):144-156
The Interdisciplinary Collaborative Team (ICT) strategy uses front-line providers as adaptation, training and quality control agents for multi-agency EBT implementation. This study tests whether an ICT transmits fidelity to subsequent provider cohorts. SafeCare was implemented by home visitors from multiple community-based agencies contracting with child welfare. Client-reported fidelity trajectories for 5,769 visits, 957 clients and 45 providers were compared using three-level growth models. Provider cohorts trained and live-coached by the ICT attained benchmark fidelity after 12 weeks, and this was sustained. Hispanic clients reported high cultural competency, supporting a cultural adaptation crafted by the ICT. 相似文献
996.
997.
Arteaga-Müller Giovanna Yazmin Olivo-Gutierrez Mara Favela-Aragon Karla Lizbeth Hernández-Castillo Paola Alejandra Esquivel-Gomez Victor Camacho-Ortiz Adrian 《International urology and nephrology》2022,54(2):457-458
International Urology and Nephrology - 相似文献
998.
Rose Sisk Lijing Lin Matthew Sperrin Jessica K Barrett Brian Tom Karla Diaz-Ordaz Niels Peek Glen P Martin 《J Am Med Inform Assoc》2021,28(1):155
ObjectiveInformative presence (IP) is the phenomenon whereby the presence or absence of patient data is potentially informative with respect to their health condition, with informative observation (IO) being the longitudinal equivalent. These phenomena predominantly exist within routinely collected healthcare data, in which data collection is driven by the clinical requirements of patients and clinicians. The extent to which IP and IO are considered when using such data to develop clinical prediction models (CPMs) is unknown, as is the existing methodology aiming at handling these issues. This review aims to synthesize such existing methodology, thereby helping identify an agenda for future methodological work.Materials and MethodsA systematic literature search was conducted by 2 independent reviewers using prespecified keywords.ResultsThirty-six articles were included. We categorized the methods presented within as derived predictors (including some representation of the measurement process as a predictor in the model), modeling under IP, and latent structures. Including missing indicators or summary measures as predictors is the most commonly presented approach amongst the included studies (24 of 36 articles).DiscussionThis is the first review to collate the literature in this area under a prediction framework. A considerable body relevant of literature exists, and we present ways in which the described methods could be developed further. Guidance is required for specifying the conditions under which each method should be used to enable applied prediction modelers to use these methods.ConclusionsA growing recognition of IP and IO exists within the literature, and methodology is increasingly becoming available to leverage these phenomena for prediction purposes. IP and IO should be approached differently in a prediction context than when the primary goal is explanation. The work included in this review has demonstrated theoretical and empirical benefits of incorporating IP and IO, and therefore we recommend that applied health researchers consider incorporating these methods in their work. 相似文献
999.
Rebecca A. Seguin-Fowler Karla L. Hanson Grace A. Marshall Emily H. Belarmino Stephanie B. Jilcott Pitts Jane Kolodinsky Marilyn Sitaker Alice Ammerman 《Nutrients》2021,13(3)
Accurate measurement of fruit and vegetable (FV) intake is important for nutrition surveillance and evaluation of dietary interventions. We compared two tools for reporting FV intake to objective measurement of skin carotenoids among children. FV cups/day was assessed by repeated 24 h dietary recalls (24H FV) and the National Cancer Institute’s All-Day Fruit and Vegetable Screener (NCI FV). Skin carotenoids were measured by repeated resonance Raman spectroscopy (RRS) of the palm. FV cups were regressed on RRS scores in unadjusted, field-based, and research-setting models with covariates feasible in each scenario. Data were baseline values from children aged 2–12 years in low-income households enrolled in a healthy eating randomized trial in four U.S. states (n = 177). Twenty-four-hour FV cups were associated with skin carotenoids in all models (p < 0.001) but NCI FV cups were not. Predicted RRS scores for discrete 24H FV cups provide a guide to interpretation of RRS in children (2 cups FV intake ~36,000 RRS units), with the research-setting scenario generally providing the narrowest prediction range (+/−1924). When self-reported data are required, 24 h recalls are more accurate than NCI FV screener data; and, when limited time, resources, or literacy must be considered, RRS scores can be quickly obtained and easily interpreted. 相似文献
1000.
Karla A. Bascun Juan Manuel Rodríguez Carla Osben Alan Fernndez Carlos Sepúlveda Magdalena Araya 《Nutrients》2021,13(6)
The COVID-19 pandemic has been present for many months, influencing diets such as the gluten-free diet (GFD), which implies daily challenges even in non-pandemic conditions. Persons following the GFD were invited to answer online ad hoc and validated questionnaires characterizing self-perceptions of the pandemic, current clinical condition, dietary characteristics, adherence to GFD, anxiety, and depression. Of 331 participants, 87% experienced shortage and higher cost of food and 14.8% lost their jobs. Symptoms increased in 29% and 36.6% failed to obtain medical help. Although 52.3% increased food preparation at home and purchased alternative foodstuffs, 53.8% had consumed gluten-containing foods. The Health Eating Index was intermediate/“needs improvement” (mean 65.6 ± 13.3 points); in 49.9% (perception) and 44.4% (questionnaire), adherence was “bad”. Anxiety and depression scores were above the cutoff in 28% and 40.4%, respectively. Adherence and mental health were strongly related. The likelihood of poor adherence was 2.3 times higher (p < 0.004) in participants declaring that pandemic altered GFD. Those suffering depressive symptoms were 1.3 times more likely to have poor adherence (p < 0.000). Depression and faulty GFD (mandatory for treatment) appear, affecting a high proportion of participants, suggesting that support measures aimed at these aspects would help improve the health condition of people that maintain GFD. Comparisons of data currently appearing in the literature available should be cautious because not only cultural aspects but conditions and timing of data collection are most variable. 相似文献