Dorsolateral periaqueductal grey matter and pontine A5 region connectivity: a neuropharmacologic and electrophysiological study

In this study, carried out in spontaneously breathing anesthetised rats, we have analysed the relevance of the interactions between the dorsolateral periaqueductal grey matter (dlPAG) and the A5 region, and how this sympathetic pontine region participates in modulating the cardiorespiratory response evoked from the dlPAG. Electrical stimulation of the dlPAG (1 ms pulses, 20-30 μA given at 100 Hz for 5s) was elicited, and the evoked cardiorespiratory changes were analysed before and after ipsilateral microinjections of muscimol (50 nl, 0.25 nmol, 5s) within the A5 region. DlPAG stimulation evoked the classical “defence response” characterized by tachipnoea, hypertension and tachycardia. Tachipnoea consisted of an inspiratory facilitatory response [increase in respiratory rate (p<0.001) due to a decrease in expiratory time (p<0.01)] and was accompanied by a pressor (p<0.001) and tachycardic (p<0.001) response. Microinjection of Muscimol within the A5 region reduced all, pressor (p<0.05), heart rate (p<0.001) and respiratory (p<0.001) responses evoked by electrical stimulation of dlPAG. Finally, extracellular recordings of putative A5 neurones were obtained during dlPAG electrical stimulation in order to assess functional interactions between A5 and dlPAG. Forty A5 cells were recorded, 16 of which were affected by dlPAG (40%). With these results, we can conclude that neurones of the A5 region possibly modulate the cardiorespiratory response evoked from the dlPAG.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Does the midbrain dorsolateral periaqueductal grey have direct connections with the pontine A5 region? A neuropharmacologic and electrophysiological study

This study has been performed in spontaneously breathing anesthetised rats. We have analysed the possible interactions between the midbrain dorsolateral periaqueductal grey matter (dlPAG) and the pontine A5 region. Electrical stimulations of the dlPAG (1 ms pulses, 20-30 μA given at 100 Hz for 5s) were elicited and the evoked cardiorespiratory changes were analysed before and after ipsilateral blockade of the neurotransmission within the A5 region by means of microinjections of muscimol (50 nl, 0.25 nmol, 5s). Electrical stimulations evoked the classical “defence response” characterized by tachipnoea, hypertension and tachycardia. Tachipnoea consisted of an inspiratory facilitatory response [increase in respiratory rate (p<0.001) due to a decrease in expiratory time (p<0.01)] and was accompanied by a pressor (p<0.001) and tachycardic (p<0.001) response. Muscimol microinjected within the A5 region reduced pressor (p<0.05), tachycardic (p<0.001) and tachypnoeic (p<0.001) responses evoked to dlPAG electrical stimulations. Finally, in order to assess functional interactions between A5 and dlPAG, extracellular recordings of 40 putative A5 cells during dlPAG electrical stimulation were recorded. 16 cells were affected by dlPAG stimulation (40%). 3 cells showed orthodromic activation (14.2 ± 1.7 ms). 5 cells were excited (10.1 ± 1.6 ms). 7 cells decreased spontaneous activity to dlPAG stimulation. 24 cells were not modified by dlPAG stimulation (2 presented a respiratory pattern and 1 presented a cardiovascular pattern). These results contribute with new data on the role of the A5 region neurones in the modulation of the cardiorespiratory response evoked on dlPAG stimulation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

A Review of the Carbon Footprint of Cu and Zn Production from Primary and Secondary Sources

Copper (Cu) and zinc (Zn) with their unique properties are central for economic growth, quality of life, and the creation of new jobs. The base-metal producing sector is, however, under growing public pressure in respect to energy and water requirements and needs to meet several challenges, including increased demand and lower ore grades, which are generally associated with larger resource use. The development of technologies for metal production from secondary sources is often motivated by increased sustainability, and this paper aims to provide further insights about one specific aspect of sustainability—namely, climate change. The paper presents a review of carbon footprints (CF) for Cu and Zn produced from primary and secondary raw materials by analyzing data taken from scientific literature and the Ecoinvent database. Comparisons are carried out based on the source of data selected as a reference case. The data available in the literature indicate that secondary production of Cu and Zn has the potential to be more beneficial compared to primary production regarding the impact on climate change. However, the technologies used today for the production of both metals from secondary sources are still immature, and more research on this topic is needed. The general variation of data suggests that the standardization of a comparison is needed when assessing the environmental benefits of production in line with the principles of waste valorization, the zero waste approach, and circular econom

Functional Characterization of MODY2 Mutations Highlights the Importance of the Fine-Tuning of Glucokinase and Its Role in Glucose Sensing

Glucokinase (GK) acts as a glucose sensor in the pancreatic beta-cell and regulates insulin secretion. Heterozygous mutations in the human GK-encoding GCK gene that reduce the activity index increase the glucose-stimulated insulin secretion threshold and cause familial, mild fasting hyperglycaemia, also known as Maturity Onset Diabetes of the Young type 2 (MODY2). Here we describe the biochemical characterization of five missense GK mutations: p.Ile130Thr, p.Asp205His, p.Gly223Ser, p.His416Arg and p.Ala449Thr. The enzymatic analysis of the corresponding bacterially expressed GST-GK mutant proteins show that all of them impair the kinetic characteristics of the enzyme. In keeping with their position within the protein, mutations p.Ile130Thr, p.Asp205His, p.Gly223Ser, and p.His416Arg strongly decrease the activity index of GK, affecting to one or more kinetic parameters. In contrast, the p.Ala449Thr mutation, which is located in the allosteric activator site, does not affect significantly the activity index of GK, but dramatically modifies the main kinetic parameters responsible for the function of this enzyme as a glucose sensor. The reduced Kcat of the mutant (3.21±0.28 s−1 vs 47.86±2.78 s−1) is balanced by an increased glucose affinity (S0.5 = 1.33±0.08 mM vs 7.86±0.09 mM) and loss of cooperativity for this substrate. We further studied the mechanism by which this mutation impaired GK kinetics by measuring the differential effects of several competitive inhibitors and one allosteric activator on the mutant protein. Our results suggest that this mutation alters the equilibrium between the conformational states of glucokinase and highlights the importance of the fine-tuning of GK and its role in glucose sensing

Hypoxia Inducible Factor 1-Alpha (HIF-1 Alpha) Is Induced during Reperfusion after Renal Ischemia and Is Critical for Proximal Tubule Cell Survival

Acute tubular necrosis (ATN) caused by ischemia/reperfusion (I/R) during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α), using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant

Potencia anaeróbica aláctica en mujeres jóvenes con diferentes niveles de actividad física

Los objetivos del presente trabajo fueron establecer valores medios de Potencia Anaeróbica Aláctica (P.A.A.) en mujeres jóvenes, determinar si existía diferencia significativa entre los valores de P.A.A. en los grupos con varios niveles de entrenamiento y compararlos con valores previamente reportados en hombres. La P.A.A. fue determinada en 62 jóvenes voluntarias de 17 y 21 años de edad. La población fue dividida en tres grupos de acuerdo al nivel de actividad física. Grupo I: 22 jóvenes sedentarias, sin actividad físicodeportiva regular. Grupo II : 20 estudiantes de educación física, con actividad fisico-deportiva regular pero no competitiva. Grupo III : 19 velocistas con actividad físico-deportiva regular competitiva. La P.A A. fue estimada con el método descrito por Margaria

A study of anthropometric, biochemical and nutritional parameters in adolescents in the area of Toledo, Spain.

Background. An incrementation of risk of cardiovascular disease (CVD) in the younger population has been reported in Spain. Adolescents have changed their dietary habits and increased the risk of metabolic syndrome (MS). The Longitudinal study in the area of Toledo aims to evaluate food intake and nutritional habits and their relationship with early development of CVD and insulin resistance/sensitivity biomarkers.Methods. A cross-sectional study was performed on 53 adolescents aged 16-17 years belonging to the Area of Toledo. Energy, macronutrient and micronutrient intakes and diet quality were assessed, as well as the prevalence to being overweight, the presence of CVD risk factors and parameters related to glucose homeostasis to identify candidates for MS.Results. Adolescents consumed monotonous diets, with low Mediterranean diet Adherence (MDA) and Health Eating Index (HEI) scores and with elevated energy contribution of saturated fatty acids and low carbohydrates. Being overweight but not obese was moderately prevalent in volunteers. However, a low percentage of them showed dyslipemia or insulin resistance. No significant differences between male and female adolescents were found for any dietary parameter tested. HEI and MDA scores appear inversely related to insulin resistance markers in boys and to fat mass in girls, respectively.Conclusions. The high similitude of diet in both male and female subjects suggests a general adherence to potentially negative dietary habits in this population. Paradoxically, dietary components and altered lipoprotein factors were not related. The prevalence to being overweight, the association between diet quality and MS-markers found demands a follow-up study to ascertain the importance of present results later in life

Effect of mutation p.Ala449Thr on the GK interaction with GKRP.

<p>A) Inhibition of glucokinase activity by human GKRP. Enzyme activity was measured at 5 mM glucose as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030518#s2" target="_blank">Material and Methods</a>, in the presence of 10 µM S6P (left panel) or 0.2 mM F1P (right panel). Results are means ± SEM for three independent enzyme purifications assayed in triplicate. B) Two-hybrid interaction of GBD-GKRP with GAD-GK or GAD-GK(p.Ala449Thr) mutant. Yeast strain Y187 was used, and fusion proteins were expressed from pGBKT7 and pACTII derivatives. Values are means ± SEM from ß-galactosidase activity of six independent transformants. In control experiments, GBD-GKRP did not interact with GAD and GAD-GK did not interact with GBD <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030518#pone.0030518-Galan1" target="_blank">[22]</a>.</p

Clinical characteristics of probands and <i>GCK</i> mutations.

<p>BMI: body mass index; FPG: fasting plasma glucose; OGTT: plasma glucose at 120 min after a standard oral glucose tolerance test (1.75 g per kg, máx. 75 g). Nucleotide numbering uses +1 as the A of the ATG initiation codon, based on the GenBank sequence # NM_000162. F, father; M, mother; S, sister; pGF, paternal grandfather; mGF, maternal grandfather; mGM, maternal grandmother. NA, not analysed. Underlined are those affected family members where mutation was checked by genotyping. Novel mutations are shown in bold.</p

Inhibition of GK activity by mannoheptulose (MH), N-acetylglucosamine (NAG) and palmitoyl-CoA.

<p>The GST-GK enzyme was assayed at 5 mM glucose with the indicated concentration of inhibitors as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030518#s2" target="_blank">Material and Methods</a>. Means and SEM of three independent enzyme preparations are shown.</p