Comparative analysis of sediment quality indices using different reference values in an environmental protection area in Southeastern Brazil.

Contamination of aquatic ecosystems by potentially toxic elements (PTEs) is a concerning environmental issue, given their persistence, toxicity potential, and ability to accumulate in living organisms. Several studies have been conducted to assess the contamination of aquatic ecosystems by PTEs, using pollution and ecological risk indices that rely on the concentration of these elements in aquatic sediments. However, many of these studies use global reference values for calculating the indices, which can lead to misleading interpretations due to substantial variations in PTEs concentrations influenced by the geological characteristics of each region. Therefore, the use of regional reference values is more appropriate when available. This study aimed to investigate variations in the results of five indices, employing global, regional, and quality reference values, based on sediment samples collected from rivers in the Ipanema National Forest, a protected area in Brazil exposed to various anthropogenic pressures. The results revealed that elements such as Al, Fe, and Mn exceeded the limits allowed by legislation in water samples, while As and Cr surpassed the limits in sediment samples. Comparative analysis highlighted significant discrepancies in the results of the indices when global reference values were used compared to regional and quality reference values, especially for As and Ba. Thus, this study underscores the importance of establishing specific regional values for an accurate assessment of sediment quality and the risks associated with contamination by PTEs in different regions worldwide.

Face, Content, and Construct Validity of Brain Tumor Microsurgery Simulation Using a Human Placenta Model.

BACKGROUND: Brain tumors are complex 3-dimensional lesions. Their resection involves training and the use of the multiple microsurgical techniques available for removal. Simulation models, with haptic and visual realism, may be useful for improving the bimanual technical skills of neurosurgical residents and neurosurgeons, potentially decreasing surgical errors and thus improving patient outcomes. OBJECTIVE: To describe and assess an ex vivo placental model for brain tumor microsurgery using a simulation tool in neurosurgical psychomotor teaching and assessment. METHODS: Sixteen human placentas were used in this research project. Intravascular blood remnants were removed by continuous saline solution irrigation of the 2 placental arteries and placental vein. Brain tumors were simulated using silicone injections in the placental stroma. Eight neurosurgeons and 8 neurosurgical residents carried out the resection of simulated tumors using the same surgical instruments and bimanual microsurgical techniques used to perform human brain tumor operations. Face and content validity was assessed using a subjective evaluation based on a 5-point Likert scale. Construct validity was assessed by analyzing the surgical performance of the neurosurgeon and resident groups. RESULTS: The placenta model simulated brain tumor surgical procedures with high fidelity. Results showed face and content validity. Construct validity was demonstrated by statistically different surgical performances among the evaluated groups. CONCLUSION: Human placentas are useful haptic models to simulate brain tumor microsurgical removal. Results using this model demonstrate face, content, and construct validity.

Cesariana perimortem / Perimortem caesarean

O termo cesariana perimortem refere-se à realização de parto via cesariana em situação de gestante in extremis ou sob ressuscitação cardiopulmonar. O objetivo deste estudo é encontrar na literatura evidências que permitam uma prática mais consistente e otimizada da cesariana perimortem. Foi realizada uma revisão sistemática a partir de um levantamento bibliográfico nas bases de dados eletrônicas Scientific Electronic Library Online (SciELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) e Medical Literature Analysis and Retrieval System Online (Medline), onde foram selecionados 24 artigos para leitura completa. As questões consideradas foram: principais indicações da cesareana perimortem; implicações da presença do feto intrautero na ressuscitação cardiopulmonar; momento adequado para realização do procedimento e sua interferência na sobrevida materna e fetal. A abordagem de uma gestante com parada cardíaca deve ser multidisciplinar e precoce, com extração do feto idealmente com cinco minutos pós parada cardíaca, o que reduz significativamente as taxas de mortalidade perinatal e materna.(AU)

Perimortem caesarean section refers to caesarean section performed in cases where the pregnant is in extremis or is undergoing cardiopulmonary resuscitation. Our objective was finding evidences in the literature to endorse a more consistent and optimized practice of this procedure. We designed a systematic review based on Scientific Eletronic Library Online (SCIELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) and Medical Literature Analysis and Retrieval System Online (Medline) from where we selected 24 articles to complete reading. We considered these issues: main indications of perimortem caesarean; implications of the presence of intrauterine infant on the maternal resuscitation; adequate moment to proceed to the perimortem cesarean and its impacts on maternal and infant?s outcomes. The management of maternal collapse must be multidisciplinary and precocial, with the baby being extracted within five minutes after cardiac arrest, what is fundamental to improve outcomes of both, mother and child.(AU)