Influence of Intact Mycelium of Arbuscular Mycorrhizal Fungi on Soil Microbiome Functional Profile in Wheat under Mn Stress.

In the current agronomic context, the adoption of alternative forms of soil management is essential to increase crop yield. Agricultural sustainability requires practices that generate positive impacts and promote an increase in microbiome diversity as a tool to overcome adverse environmental conditions. An important ally is the indigenous arbuscular mycorrhizal fungi (AMF) that can improve plant growth and provide protection against abiotic stress such as metal toxicity. In a greenhouse experiment, this work studied the effect of wheat growth on several parameters of biological activity and functional microbiome in relation to wheat antecedent plant mycotrophy and soil disturbance under Mn stress. When the wheat was planted after highly mycotrophic plants and the soil was not previously disturbed, the results showed a 60% increase in wheat arbuscular colonization and a 2.5-fold increase in dry weight along with higher values of photosynthetic parameters and dehydrogenase activity. Conversely, soil disturbance before wheat planting increased the ß-glucosidase activity and the count of manganese oxidizers, irrespectively of antecedent plant, and decreased drastically the wheat dry weight, the AMF colonization and the chlorophyll content compared to the undisturbed treatment. These findings suggest that not only the wheat growth but also the soil functional microbiome associated is affected by the antecedent type of plant and previous soil disturbance imposed. In addition, the improvement in wheat dry weight despite Mn toxicity may rely on shifts in biological activity associated to a well-established and intact ERM early developed in the soil.

Evaluation of slurry sampling preparation of enteral nutrition formulations for multielement determination using inductively coupled plasma optical emission spectrometry.

An analytical procedure for the multielement determination in enteral nutrition formulations employing slurry sampling and inductively coupled plasma optical emission spectrometry (ICP OES) is proposed. A two-level full-factorial design was applied to assess the influence of the presence of stabilizing agents (HNO3, Triton X-100 and ethanol) on the composition of the slurry. Multiple response was established as a dependent variable. The experimental conditions for the preparation of the slurry were: 2.0 mL of sample and 8.0 mL of 10% (v/v) HNO3. The limits of detection (LOD) were 5; 9; and 10 µg L-1 for Cu, Fe, Zn, respectively. For P, and K, the LOD were 8 and 24 mg L-1, respectively. The method was applied for the analysis of three enteral nutrition formulation samples and the obtained concentrations ranges were (in mg L-1): 0.41-0.43 (Cu), 2.0-2.9 (Fe), 1.7-3.1 (Zn), 682-1409 (K), and 217-344 (P).

Marginal and internal fit of CAD-CAM composite resin and ceramic crowns before and after internal adjustment.

STATEMENT OF PROBLEM: With the development of computer-aided design and computer-aided manufacturing (CAD-CAM) technology, dentists may determine internal spacing by using the CAD-CAM software program and make internal adjustments during the clinical evaluation appointment. How these factors affect marginal adaptation is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the marginal and internal adaptation of CAD-CAM ceramic and composite resin crowns with different internal spacings before and after internal adjustment by using microcomputed tomography. MATERIAL AND METHODS: Eight third molars were prepared for a complete crown, and 32 crowns were milled at chairside from composite resin and ceramic materials with different internal spacing (30 µm and 80 µm). After an initial microcomputed tomography scan, the same crowns were adjusted and scanned again. Axial space, occlusal space (OS), marginal discrepancy, and absolute marginal discrepancy were evaluated in both analyses. The need for internal adjustment was determined by an experienced clinician by using a silicone film. The number of internal adjustments was also recorded. The data were analyzed by using a 3-way ANOVA (material, internal spacing, and internal adjustment) and the Bonferroni correction (α=.05). RESULTS: For axial space, only the material factor was significantly different (P<.001), with the ceramic having the lowest value. For OS, both internal spacing and adjustments presented a statistical difference among groups with the lowest OS values obtained for 80-µm spacing after adjustment. For marginal discrepancy and absolute marginal discrepancy, the adjustment factor also had a significant effect, and the adjustment resulted in smaller measures for both variables. The 30-µm spacing required more adjustments than the 80-µm spacing (P<.05). CONCLUSIONS: Both the internal adaptation and marginal adaptation were influenced by the internal adjustment, resulting in improved values for both. Although no differences were observed between the 30-µm and 80-µm spacings after internal adjustment for marginal adaptation, the 30-µm spacing required twice as many adjustments, resulting in longer clinical sessions.

Critical review of the quality and development of randomized clinical trials (RCTs) and their influence on the treatment of advanced epithelial ovarian cancer.

Trials on chemotherapy of advanced ovarian cancer published between 1975-88 were systematically reviewed for quality (according to the method of Chalmers) and consistency of tested hypotheses with a view to a meta-analysis of all published studies in the field. Median overall, internal and external validity scores were 47%, 43% and 53%, respectively. No association was found between scores and key features of trials, such as percentage studies with significant results in response or survival or percentage studies with high or low follow-up retention (withdrawal rates less than or greater than or equal to 15%). Only 21% of trials reported a fully blind randomization procedure and only in 13% were drop-outs accounted for by the intent-to-treat method. Only 4 trials entered more than 150 patients per arm, a sample size consistent with detection of an absolute difference of 11% in mortality. The majority of trials (58%) investigated the role of combination regimens versus a single-agent control arm. The remaining trials tested different polychemotherapies. However, within these two general issues, treatment options were quite heterogeneous: seven subgroups were identified by whether cisplatin was present in either the treatment or the control arm. We conclude that the internal coherence and development of randomized clinical trials in advanced ovarian cancer and their methodologic soundness are quite poor. In this situation meta-analysis cannot go beyond a systematic attempt to answer a very general "treatment effectiveness" question.