The Principles of Biomedical Scientific Writing: Materials and Methods.

The materials and methods (M&M) section is the heart of a scientific paper and is subject to initial screening of the editor to decide whether the manuscript should be sent for external review. If the M&M section of a scientific paper be considered as a recipe, its ingredients would be who, what, when, where, how, and why. M&M should effectively respond to the study question/hypothesis using the following basic elements including materials, study design, study population/subjects or animals, methods of measurements/assessments, and statistical analysis. A well-organized M&M permits other scientists to evaluate the study findings and repeat the experiments. Although there are several disciplinary differences in the M&M, similar dos and don'ts may be considered to organize a well-written M&M. Briefly, authors need to provide clear-cut, adequate, and detailed information in the M&M section. In this review, the structure, the principles, and the most common recommendations for writing the M&M section are provided, both in general and study-specific; these could help authors effectively prepare the M&M section of a scientific biomedical manuscript.

Prácticas pa ra la prevención de accidentes en el hogar en cuidadores de niños de 1 a 5 años en un barrio de Cartagena (Colombia) / Practices for the prevention of accidents in the home in caregivers of children from 1 to 5 years in a district of Cartagena (Colombia)

Introducción: los accidentes en la población infantil constituyen una importante causa de morbilidad y mortalidad convirtiéndose hoy día en un problema de salud pública mundial, principalmente la población más afectada son los niños en etapa preescolar, por la vulnerabilidad y dependencia del cuidador. Objetivos: describir las prácticas para la prevención de accidentes en el hogar en cuidadores de niños de 1 a 5 años en un barrio de Cartagena (Colombia). Materiales y métodos: estudio cuantitativo descriptivo transversal. Constituido por 354 cuidadores de niños menores de 5 años, se utilizó la técnica de observación y la aplicación del instrumento con base a la práctica N° 15 de AIEPI (Atención Integrada a las Enfermedades Prevalentes de la Infancia). Resultados: socio demográficamente los cuidadores fueron principalmente de género femenino (87%), con 20 ­ 29 años de edad (44,9%), madres de los niños (61,3%), conviven en unión libre (54,2%), son bachilleres (50,3%), de estrato uno (91,8%), amas de casa (62,7%), con hijos (93,8%), residen en casas (54,5%). Los niños de 1 a 5 años fueron mayoritariamente de género masculino (51,7%), y han presentado accidentes (75,1%), sobre todo, caídas (61,9%). El nivel de riesgo de accidentes en el hogar fue bajo (85%), y las prácticas de prevención suelen ser regulares (55,1%). Conclusión: los niños enfrentan relativamente bajo riesgo de accidente en el hogar, sin embargo, las prácticas para prevenirlos resultan ser regulares..(AU)

Introduction: accidents in children are an important cause of morbidity and mortality,becoming today a global public health problem, mainly the most affected population are children in preschool, for the vulnerability and dependence of the caregiver. Objectives:to describe the practices for the prevention of accidents at home in caregivers of children from 1 to 5 years of age, in a neighborhood of Cartagena (Colombia). Materials and methods: quantitative, descriptive and cross-sectional study. Consisting of 354 caregivers of children under 5 years of age, the technique of observation and the application of the instrument was used based on practice No. 15 of IMCI (Integrated Management of Childhood Illness). Results: demographic partner caregivers were mainly female (87%), with 20 - 29 years of age (44.9%), mothers of children (61.3%), live together in a free union (54.2%), are high school graduates (50.3%), of stratum one (91.8%), housewives (62.7%), with children (93.8%), reside in houses (54.5%). Children from 1 to 5 years old were male (51.7%), and had accidents (75.1%), especially falls (61.9%). The level of accident risk in the home was low (85%), and prevention practices are usually regular (55.1%). Conclusion: children face relatively low risk of accident in the home, however, practices to prevent them turn out to be regular..(AU)

Histology Strategies for Medical Implants and Interventional Device Studies.

Histology of medical devices poses a variety of unique challenges. Comprehensive histologic assessment of medical devices often requires spatial context and high-quality retention of the device-tissue interface. However, the composition of many medical devices is often not amenable to traditional paraffin embedding and thus alternative specialized methodologies such as hard resin embedding must be used. Hard resin embedding requires specialized laboratory technical expertise and equipment, and the fixation techniques and resin composition used markedly impact the feasibility of immunohistochemistry. For the continuity of spatial context during histologic evaluation, additional imaging methods such as macrophotography, radiography, micro-Computerized Tomography (microCT), or magnetic resonance imaging (MRI) can be used to guide sectioning and to complement histologic findings. Although standardized approaches are scarce for medical devices, important considerations specific to medical device histology are discussed, including general specimen preparation, special considerations for devices by organ system, and the challenges of immunohistochemistry. Histologic preparation of medical devices must be thoughtful, thorough, and tailored to achieve optimal histologic outcomes for complex, valuable, and often limited implant specimens.

How to design in situ studies: an evaluation of experimental protocols.

OBJECTIVES: Designing in situ models for caries research is a demanding procedure, as both clinical and laboratory parameters need to be incorporated in a single study. This study aimed to construct an informative guideline for planning in situ models relevant to preexisting caries studies. MATERIALS AND METHODS: An electronic literature search of the PubMed database was performed. A total 191 of full articles written in English were included and data were extracted from materials and methods. Multiple variables were analyzed in relation to the publication types, participant characteristics, specimen and appliance factors, and other conditions. Frequencies and percentages were displayed to summarize the data and the Pearson's chi-square test was used to assess a statistical significance (p < 0.05). RESULTS: There were many parameters commonly included in the majority of in situ models such as inclusion criteria, sample sizes, sample allocation methods, tooth types, intraoral appliance types, sterilization methods, study periods, outcome measures, experimental interventions, etc. Interrelationships existed between the main research topics and some parameters (outcome measures and sample allocation methods) among the evaluated articles. CONCLUSIONS: It will be possible to establish standardized in situ protocols according to the research topics. Furthermore, data collaboration from comparable studies would be enhanced by homogeneous study designs.

How to design in situ studies: an evaluation of experimental protocols

OBJECTIVES: Designing in situ models for caries research is a demanding procedure, as both clinical and laboratory parameters need to be incorporated in a single study. This study aimed to construct an informative guideline for planning in situ models relevant to preexisting caries studies. MATERIALS AND METHODS: An electronic literature search of the PubMed database was performed. A total 191 of full articles written in English were included and data were extracted from materials and methods. Multiple variables were analyzed in relation to the publication types, participant characteristics, specimen and appliance factors, and other conditions. Frequencies and percentages were displayed to summarize the data and the Pearson's chi-square test was used to assess a statistical significance (p < 0.05). RESULTS: There were many parameters commonly included in the majority of in situ models such as inclusion criteria, sample sizes, sample allocation methods, tooth types, intraoral appliance types, sterilization methods, study periods, outcome measures, experimental interventions, etc. Interrelationships existed between the main research topics and some parameters (outcome measures and sample allocation methods) among the evaluated articles. CONCLUSIONS: It will be possible to establish standardized in situ protocols according to the research topics. Furthermore, data collaboration from comparable studies would be enhanced by homogeneous study designs.

On the reproducibility of science: unique identification of research resources in the biomedical literature.

Scientific reproducibility has been at the forefront of many news stories and there exist numerous initiatives to help address this problem. We posit that a contributor is simply a lack of specificity that is required to enable adequate research reproducibility. In particular, the inability to uniquely identify research resources, such as antibodies and model organisms, makes it difficult or impossible to reproduce experiments even where the science is otherwise sound. In order to better understand the magnitude of this problem, we designed an experiment to ascertain the "identifiability" of research resources in the biomedical literature. We evaluated recent journal articles in the fields of Neuroscience, Developmental Biology, Immunology, Cell and Molecular Biology and General Biology, selected randomly based on a diversity of impact factors for the journals, publishers, and experimental method reporting guidelines. We attempted to uniquely identify model organisms (mouse, rat, zebrafish, worm, fly and yeast), antibodies, knockdown reagents (morpholinos or RNAi), constructs, and cell lines. Specific criteria were developed to determine if a resource was uniquely identifiable, and included examining relevant repositories (such as model organism databases, and the Antibody Registry), as well as vendor sites. The results of this experiment show that 54% of resources are not uniquely identifiable in publications, regardless of domain, journal impact factor, or reporting requirements. For example, in many cases the organism strain in which the experiment was performed or antibody that was used could not be identified. Our results show that identifiability is a serious problem for reproducibility. Based on these results, we provide recommendations to authors, reviewers, journal editors, vendors, and publishers. Scientific efficiency and reproducibility depend upon a research-wide improvement of this substantial problem in science today.