Diversidad genética de dos especies de coníferas en el Nevado de Toluca. Una alternativa de conservación

Se analizó la variabilidad genética de Pinus hartwegii y Abies religiosa en 27 y 17 puntos de muestreo, respectivamente, situados en el Área de Protección de Flora y Fauna Nevado de Toluca, un Área Natural Protegida que por su ubicación geográfica se encuentra bajo diferentes presiones antropogénicas, las cuales a su vez generan problemas ambientales. Particularmente en los bosques de pino y oyamel existe tala ilegal y desmedida lo que provoca la propagación de plagas y enfermedades en estas coníferas, como el aumento de muérdagos enanos (Arceuthobium spp.) y de escarabajos descortezadores (Dendroctonus spp., Pseudohylesinus spp.). Se utilizaron marcadores genéticos como: secuencias simples repetidas ancladas (assr), dna mitocondrial (mtdna), dna de cloroplasto (cpdna) e isoenzimas, para determinar niveles de heterocigocidad, número de alelos, flujo génico, diferenciación poblacional y distancias genéticas. Se encontraron niveles de diversidad genética bajos para P. hartwegii y altos para A. religiosa, con base en estos resultados se realizaron propuestas de conservación para ambas especies

Active Human and Porcine Serum Induce Competence for Genetic Transformation in the Emerging Zoonotic Pathogen Streptococcus suis.

The acquisition of novel genetic traits through natural competence is a strategy used by bacteria in microbe-rich environments where microbial competition, antibiotics, and host immune defenses threaten their survival. Here, we show that virulent strains of Streptococcus suis, an important zoonotic agent and porcine pathogen, become competent for genetic transformation with plasmid or linear DNA when cultured in active porcine and human serum. Competence was not induced in active fetal bovine serum, which contains less complement factors and immunoglobulins than adult serum and was strongly reduced in heat-treated or low-molecular weight fractions of active porcine serum. Late competence genes, encoding the uptake machinery for environmental DNA, were upregulated in the active serum. Competence development was independent of the early competence regulatory switch involving XIP and ComR, as well as sigma factor ComX, suggesting the presence of an alternative stress-induced pathway for regulation of the late competence genes required for DNA uptake

Application of the incremental step loading technique to Small Punch Tests on S420 steel in acid environments

ABSTRACT: The Small Punch test has been recently used to estimate mechanical properties of steels in aggressive environments. This technique, very interesting when there is shortage of material, consists in using a small plane specimen and punch it until it fails. The type of tests normally used are under a constant load in an aggressive environment, with the target to determine the threshold stress. However, this is an inaccurate technique which takes time, as the tests are quite slow. In this paper, the Small Punch tests are combined with the step loading technique collected in the standard ASTM F1624 [1] to obtain the value of threshold stress of an S420 steel in a total time of approximately one week. The ASTM F1624 indicates how to apply constant load steps in hydrogen embrittlement environments, increasing them subsequently and adapting their duration until the specimen fails. The environment is created by means of cathodic polarization of cylindrical tensile specimens in an acid electrolyte. A batch of standard tests are performed to validate the methodology.The present work was performed in the University of Cantabria, through the post-doctoral contracts program (budgetary application 62.0000.64251), and supported by the Government of Cantabria and the University of Cantabria in the framework of “Proyectos Puente 2019” call

Stability of Antimicrobials in Elastomeric Pumps: A Systematic Review

Antimicrobials; Elastomer; Systematic reviewAntimicrobianos; Elastómero; Revisión sistemáticaAntimicrobians; Elastòmer; Revisió sistemàticaOutpatient parenteral antimicrobial therapy (OPAThttp) programs have become an important healthcare tool around the world. Portable elastomeric infusion pumps are functional devices for ambulatory delivery of antimicrobial drugs, and their stability is an essential point to guarantee an appropriate infusion administration. We conducted a systematic review to provide a synthesis and a critical evaluation of the current evidence regarding antimicrobial stability in elastomeric pumps. Data sources were PubMed, EMBASE, and Web of Sciences. The review protocol was registered on the Center for Open Science, and it was carried out following the PRISMA guidelines. Studies were eligible if the aim was the evaluation of the physicochemical stability of an antimicrobial agent stored in an elastomeric device. Of the 613 papers identified, 33 met the inclusion criteria. The most studied group of antimicrobials was penicillins, followed by cephalosporins and carbapenems. In general, the stability results of the antimicrobials that have been studied in more than one article agree with each other, with the exception of ampicillin, flucloxacillin, and ceftazidime. The antibiotics that displayed a longer stability were glycopeptides and clindamycin. Regarding the stability of antifungals and antivirals, only caspofungin, voriconazole, and ganciclovir have been investigated. The information provided in this article should be considered in patient treatments within the OPAT setting. Further stability studies are needed to confirm the appropriate use of the antimicrobials included in this program to ensure optimal patient outcomes.This work was supported by the Sociedad Española de Farmacia Hospitalaria and the AFinf Working Group for the project “Stability study of antimicrobials under conditions analogous to the outpatient parenteral antibiotic therapy program (OPAT)”. A.G.-V. was supported by the Instituto de Salud Carlos III, co-financed by the European Development Regional Fund (“A way to achieve Europe”), Subprograma Miguel Servet (grant CP19/00159). L.H.-H. was supported by the Instituto de Salud Carlos III, Subprograma Rio Hortega (grant CM19/00152)

Comparison between xenogeneic and allogeneic adipose mesenchymal stem cells in the treatment of acute cerebral infarct: Proof of concept in rats

Background: Rat adipose tissue-derived-mesenchymal stem cells (rAD-MSCs) have proven to be safe in experimental animal models of stroke. However, in order to use human AD-MSCs (hAD-MSCs) as a treatment for stroke patients, a proof of concept is needed. We analyzed whether the xenogeneic hAD-MSCs were as safe and effective as allogeneic rAD-MSCs in permanent Middle Cerebral Artery Occlusion (pMCAO) in rats. Methods: Sprague–Dawley rats were randomly divided into three groups, which were intravenously injected with xenogeneic hAD-MSCs (2 × 106), allogeneic rAD-MSCs (2 × 106) or saline (control) at 30 min after pMCAO. Behavior, cell implantation, lesion size and cell death were evaluated. Brain markers such as GFAP (glial fibrillary acid protein), VEGF (vascular endothelial growth factor) and SYP (synaptophysin) and tumor formation were analyzed. Results: Compared to controls, recovery was significantly better at 24 h and continued to be so at 14 d after IV administration of either hAD-MSCs or rAD-MSCs. No reduction in lesion size or migration/implantation of cells in the damaged brain were observed in the treatment groups. Nevertheless, cell death was significantly reduced with respect to the control group in both treatment groups. VEGF and SYP levels were significantly higher, while those of GFAP were lower in the treated groups. At three months, there was no tumor formation. Conclusions: hAD-MSCs and rAD-MSCs were safe and without side effects or tumor formation. Both treatment groups showed equal efficacy in terms of functional recovery and decreased ischemic brain damage (cell death and glial scarring) and resulted in higher angiogenesis and synaptogenesis marker levelsThis research was supported by research grants FIS06/0575, FIS09/01606, FIS12/01754 and INVICTUS (RD12/0014/0006) (Spanish Neurovascular Network), Cellerix, and Research Institute Carlos III, Ministry of Science and Innovation of Spain

Blood component requirements in liver transplantation: effect of 2 thromboelastometry-guided strategies for bolus fibrinogen infusion, the TROMBOFIB randomized trial

Background: A low plasma fibrinogen level influences blood component transfusion. Thromboelastometry provides clinical guidance for fibrinogen replacement in liver transplantation (LT). Objectives: We hypothesized that infusions of fibrinogen concentrate to reach an A10FIBTEM value of 11 mm during LT could reduce red blood cell (RBC) and other component and fluid requirements in comparison to standard care. Methods: This randomized, blinded, multicenter trial in 3 hospitals enrolled 189 LTscheduled patients allocated to an intervention target (A10FIBTEM, 11 mm) or a standard target (A10FIBTEM, 8 mm); 176 patients underwent LT with fibrinogen replacement. Data were analyzed by intention-to-treat (intervention group, 91; control group, 85). Blood was extracted, and fibrinogen kits were prepared to bring each patient's fibrinogen level to the assigned target at the start of LT, after portal vein clamping, and after graft reperfusion. The main outcome was the proportion of patients requiring RBC transfusion during LT or within 24 hours. Results: The proportion of patients requiring RBCs did not differ between the groups: intervention, 74.7% (95% CI, 65.5%-83.3%); control, 72.9% (95% CI, 62.2%-82.0%); absolute difference, 1.8% (95% CI, −11.1% to 14.78%) (P = .922). Thrombotic events occurred in 4% of the patients in both groups; reoperation and retransplantation rates and mortality did not differ. Nearly 70% of the patients in both groups required fibrinogen concentrate to reach the target. Using an 11-mm A10FIBTEM target increased the maximum clot firmness without affecting safety. However, this change provided no clinical benefits. Conclusion: The similar low plasma fibrinogen concentrations could explain the lack of significant between-group outcomes

Predictive Value of Cardiac Magnetic Resonance Feature Tracking after Acute Myocardial Infarction: A Comparison with Dobutamine Stress Echocardiography

[EN] In acute ST-segment elevation myocardial infarction (STEMI) late gadolinium enhancement (LGE) may underestimate segmental functional recovery. We evaluated the predictive value of cardiac magnetic resonance (CMR) feature-tracking (FT) for functional recovery and whether it incremented the value of LGE compared to low-dose dobutamine stress echocardiography (LDDSE) and speckle-tracking echocardiography (STE). Eighty patients underwent LDDSE and CMR within 5-7 days after STEMI and segmental functional recovery was defined as improvement in wall-motion at 6-months CMR. Optimal conventional and FT parameters were analyzed and then also applied to an external validation cohort of 222 STEMI patients. Circumferential strain (CS) was the strongest CMR-FT predictor and addition to LGE increased the overall accuracy to 74% and was especially relevant in segments with 50-74% LGE (AUC 0.60 vs. 0.75, p = 0.001). LDDSE increased the overall accuracy to 71%, and in the 50-74% LGE subgroup improved the AUC from 0.60 to 0.69 (p = 0.039). LGE + CS showed similar value as LGE + LDDSE. In the validation cohort, CS was also the strongest CMR-FT predictor of recovery and addition of CS to LGE improved overall accuracy to 73% although this difference was not significant (AUC 0.69, p = 0.44). Conclusion: CS is the strongest CMR-FT predictor of segmental functional recovery after STEMI. Its incremental value to LGE is comparable to that of LDDSE whilst avoiding an inotropic stress agent. CS is especially relevant in segments with 50-74% LGE where accuracy is lower and further testing is frequently required to clarify the potential for recovery.This research was supported by the Instituto de Salud Carlos III and co-funded by Fondo Europeo de Desarrollo Regional (FEDER) (grant numbers PI17/01836 and CIBERCV16/11/00486). JG and DM acknowledge financial support from the "Agencia Valenciana de la Innovacion, Generalitat Valenciana" (grant) and from the "Conselleria d'Educacio, Investigacio, Cultura i Esport, Generalitat Valenciana" (grant number AEST/2019/037).Valente, FX.; Gavara-Doñate, J.; Gutiérrez, L.; Rios-Navarro, C.; Rello, P.; Maymi, M.; Fernandez-Galera, R.... (2021). Predictive Value of Cardiac Magnetic Resonance Feature Tracking after Acute Myocardial Infarction: A Comparison with Dobutamine Stress Echocardiography. Journal of Clinical Medicine. 10(22):1-12. https://doi.org/10.3390/jcm10225261S112102

Insulin regulates neurovascular coupling through astrocytes

Mice with insulin receptor (IR)-deficient astrocytes (GFAP-IR knockout [KO] mice) show blunted responses to insulin and reduced brain glucose uptake, whereas IRdeficient astrocytes show disturbed mitochondrial responses to glucose. While exploring the functional impact of disturbed mitochondrial function in astrocytes, we observed that GFAP-IR KO mice show uncoupling of brain blood flow with glucose uptake. Since IR-deficient astrocytes show higher levels of reactive oxidant species (ROS), this leads to stimulation of hypoxia-inducible factor-1¿ and, consequently, of the vascular endothelial growth factor angiogenic pathway. Indeed, GFAP-IR KO mice show disturbed brain vascularity and blood flow that is normalized by treatment with the antioxidant N-acetylcysteine (NAC). NAC ameliorated high ROS levels, normalized angiogenic signaling and mitochondrial function in IR-deficient astrocytes, and normalized neurovascular coupling in GFAP-IR KO mice. Our results indicate that by modulating glucose uptake and angiogenesis, insulin receptors in astrocytes participate in neurovascular coupling.We are thankful to M.Garcia and R. Cañadas for technical support. This work was funded by Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED) (Instituto de Salud CarlosIII, Spain) to I.T.A., A.G., and T.I.; an Inter-CIBER project (PIE14/00061) to I.T.A.that forms part of the projects PID2019-104376RB-I00 (I.T.A.) and RTI2018-094887-B-I00 (M.N.) funded by MCIN/AEI/10.13039/501100011033; a grant from Junta de Andalucia Consejería de Economía y Conocimiento (P18-RT-2233 to A.G.) cofinanced by Programa Operativo FEDER 2014–2020; a grant from Instituto de Salud Carlos III Spain (cofinanced by FEDER funds from the European Union; PI21/00915 to A.G.); Grant PID2020-115218RB-I00 to T.I. funded by Ministerio de Ciencia e Innovación/Agencia Española de Investigación (MCIN/AEI/10.13039/501100011033); and a grant from Comunidad de Madrid through the European Social Fund (ESF)–financed programme Neurometabolismo-Comunidad de Madrid (NEUROMETAB-CM) (B2017/BMD-3700 to I.T.A.and T.I.). M.N. was also supported by the Spanish Ministry of Science and Innovation (Ramón y Cajal RYC-2016-20414). J.P.-U. was contracted by CIBERNED