Higher magnesium levels are associated with better glycaemic control and diabetes remission post-bariatric surgery.

BACKGROUND: Low Magnesium (Mg) dietary intake has been associated with increased risk of type 2 diabetes mellitus (T2DM). Furthermore, in patients with T2DM, hypomagnesemia is associated with worst glycaemic control. Bariatric surgery (BS) remains the most effective treatment in severe obesity and also provides resolution/improvement of T2DM. Our aim is to evaluate the association between Mg supplementation post-BS and Mg serum levels with diabetes status after BS. METHODS: We performed an observational study on patients with obesity and T2DM who underwent BS. Data was assessed pre-BS and one-year post-BS. RESULTS: We included a total of 403 patients with T2DM. At baseline, 43.4% of the patients had Mg deficiency. Pre-BS, patients with Mg deficiency had poorer glycaemic control - HbA1c 7.2 ± 1.6% vs 6.4 ± 1.0% (p < 0.001), fasting plasma glucose 146.2 ± 58.8 mg/dL vs 117.5 ± 36.6 mg/dL (p < 0.001) and were under a greater number of anti-diabetic drugs 1.0 (IQR 0-2.0) vs 1.0 (IQR 0-1.0) (p = 0.002). These findings persisted at one-year post-BS. At the first-year post-BS, 58.4% of the patients had total remission of T2DM and 4.1% had partial remission. Patients without Mg deficiency at one-year post-BS had higher rates of total and partial remission. Higher serum Mg levels at baseline is an independent predictor of total T2DM remission (p < 0.0001). The optimal cut-off of baseline Mg to predict total T2DM remission was 1.50 mg/dL with a sensitivity of 73% and a specificity of 58% (area under ROC = 0.65). Patients that were under Mg supplementation post-BS had serum Mg values, glycaemic control and total remission of T2DM similar to patients non-supplemented. CONCLUSION: In patients with T2DM submitted to BS, higher Mg serum levels at baseline and 1-year after BS were associated with better glycaemic control and higher rates of total T2DM remission at the first year post-BS.

Dipolar repulsion in α-halocarbonyl compounds revisited.

The concept of dipolar repulsion has been widely used to explain several phenomena in organic chemistry, including the conformational preferences of carbonyl compounds. This model, in which atoms and bonds are viewed as point charges and dipole moment vectors, respectively, is however oversimplified. To provide a causal model rooted in quantitative molecular orbital theory, we have analyzed the rotational isomerism of haloacetaldehydes OHC-CH2X (X = F, Cl, Br, I), using relativistic density functional theory. We have found that the overall trend in the rotational energy profiles is set by the combined effects of Pauli repulsion (introducing a barrier around gauche that separates minima at syn and anti), orbital interactions (which can pull the anti minimum towards anticlinal to maximize hyperconjugation), and electrostatic interactions. Only for X = F, not for X = Cl-I, electrostatic interactions push the preference from syn to anti. Our bonding analyses show how this trend is related to the compact nature of F versus the more diffuse nature of the heavier halogens.

Nature and Strength of Lewis Acid/Base Interaction in Boron and Nitrogen Trihalides.

We have quantum chemically investigated the bonding between archetypical Lewis acids and bases. Our state-of-the-art computations on the X3 B-NY3 Lewis pairs have revealed the origin behind the systematic increase in B-N bond strength as X and Y are varied from F to Cl, Br, I, H. For H3 B-NY3 , the bonding trend is driven by the commonly accepted mechanism of donor-acceptor [HOMO(base)-LUMO(acid)] interaction. Interestingly, for X3 B-NH3 , the bonding mechanism is determined by the energy required to deform the BX3 to the pyramidal geometry it adopts in the adduct. Thus, Lewis acids that can more easily pyramidalize form stronger bonds with Lewis bases. The decrease in the strain energy of pyramidalization on going from BF3 to BI3 is directly caused by the weakening of the B-X bond strength, which stems primarily from the bonding in the plane of the molecule (σ-like) and not in the π system, at variance with the currently accepted mechanism.

Thermo-mechanical characterization of NiTi orthodontic archwires with graded actuating forces.

Functionally graded NiTi orthodontic archwire was tested to assess the evolution of the actuation force as a function of the temperature. Varying actuation forces on the same orthodontic wire allow the optimization of repositioning of the different types of teeth, according its radicular support. The wire was separated into three segments: Incisive, Premolar and Molar. The functionally graded NiTi orthodontic archwire segments have distinct structural and mechanical behavior as confirmed by differential scanning calorimetry, synchrotron-based X-ray diffraction, and thermomechanical analysis. The mechanical behavior was analyzed by three-point bending tests at four different temperatures (5, 20, 25 and 37 °C). In parallel, three-point bending tests were performed by TMA analysis in a temperature range from 5 °C (from cold water) to 40 °C (hot meal). This study showed the comparison of the different segments on the same archwire, providing a better understanding of the behavior of these functionally graded materials.

Bovine endometrial cells: a source of mesenchymal stem/progenitor cells.

Endometrial mesenchymal stem/progenitor cells (eMSCs) are multipotent cells known to modulate the immune system and have clinical application for human and animal health. This makes these bovines cells attractive for dual use as cellular therapy and experimental model. The aim of this study was to isolate, evaluate the differentiation potential, immunophenotypic and immunocytochemistry characteristics, chromosomal stability, cloning efficiency, and cryopreservation response of bovine eMSCs collected in two phases of the estrous cycle. For this, cells were isolated and submitted to differentiation for adipogenic and osteogenic lineage. The cells were then characterized by flow cytometer (FC) (vimentin, CD29, CD44, MHC-II, CD34) and immunocytochemistry (vimentin, pan-cytokeratin, CD44) and submitted to cytogenetic and cloning efficiency assay. The cells were also cryopreserved using two different medium of cryopreservation and analyzed by FC for viability, necrosis, late-apoptosis + necrosis, and initial apoptosis rates before and after cryopreservation. We obtained homogeneous cell populations which have fibroblastic morphology and adherence to plastic. These cells expressed high levels of markers CD29, CD44, and vimentin, low expression levels for CD34 and no MHC-II. The cells were chromosomally stable (2n = 60) with high cloning efficiency and no difference (P > 0.05) between medium of cryopreservation or phase was observed after thawing. We showed the presence and differentiation potential of bovine eMSCs, with chromosomal stability and great response to cryopreservation with both medium, which has implications for build biobanks or development of new therapeutic approaches to combat uterine diseases or to study.

Prognosis of Patients With Traumatic Brain Injury After Implementation of a Nurse Assessment Protocol.

BACKGROUND: The prognosis of a patient with traumatic brain injury (TBI) depends on the severity of the injury, the patient's level of consciousness upon admission, and differences in treatment protocols. AIM: The aim of this study was to analyze the prognosis of TBI victims after implementation of a nurse assessment protocol. METHOD: This is a blind, nonrandomized clinical study carried out at a public emergency hospital in the state of Sergipe, Brazil. RESULTS: The study involved 480 patients with an average (SD) age of 35.7 (±16.6) years. Most of the patients were male (p = .02). In the preprotocol and postprotocol groups, motorcycle accidents (p = .023) were more frequent, with a 10.2% death rate. The clinical conditions associated with TBI and the tomographic findings were not affected in either the preprotocol or postprotocol groups (p = .07). There was a significant reduction (p = .05) in death rate from 12.6% to 7.3% and a decrease in the percentage of discharge with aftereffects from 32.8% to 22.8%. Factors independently associated with mortality were as follows: approximately 2.5 times more likely to not apply the protocol associated with an increased chance of death, followed by a 23 times higher risk of TBI severity, and age, with an odds ratio of 1.04. CONCLUSIONS: Implementing the protocol, there was a reduction of death rate of patients with severe TBI and aftereffects in patients with moderate TBI. The severity of TBI was the main independent predictive determinant of mortality, followed by nonuse of protocol and age.

Synthesis of new heterocyclic derivatives of alpha,alpha-trehalose.

Several novel N-1, N-2, and S-5 tetrazole and 1,3,4-oxadiazole derivatives of alpha,alpha-trehalose disubstituted at C-6,6', with potential synthetic and pharmacological interest were prepared from commercial tetrazoles and 1,3,4-oxadiazoles in reaction with hexa-O-benzyl-6,6'-di-O-triflyl-alpha,alpha-trehalose.