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Background: The aim of this is to explore the histological basis of vessel wall enhancement (WE) on magnetic resonance imaging (MRI), which is a strong radiological biomarker of aneurysmal prone to rupture compared to other classical risk predictors (e.g., PHASES score, size, morphology)., Methods: A prospective observational study was performed including all consecutive patients presenting with a saccular intracranial aneurysm at Vall d'Hebron University Hospital between October 2017 and May 2019. The patients underwent high-resolution 3 T MRI, and their aneurysms were classified into asymptomatic, symptomatic, and ruptured. A histological and immunohistochemical study was performed in a subgroup of patients (n = 20, of which 15 presented with WE). Multiple regression analyses were performed to identify predictors of rupture and aneurysm symptoms., Results: A total of 132 patients were enrolled in the study. WE was present in 36.5% of aneurysms: 22.9% asymptomatic, 76.9% symptomatic, and 100% ruptured. Immunohistochemical markers associated with WE were CD3 T cell receptor (p = 0.05) and CD45 leukocyte common antigen (p = 0.05). Moreover, WE is an independent predictor of symptomatic and ruptured aneurysms (p < 0.001)., Conclusions: Aneurysms with WE present multiple histopathological changes that may contribute to wall disruption and represent the pathophysiological basis of radiological WE. Moreover, WE is an independent diagnostic predictor of aneurysm symptoms and rupture., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Progressive gray matter volume reductions beyond the epileptogenic area has been described in temporal lobe epilepsy. There is less evidence regarding correlations between gray and white matter volume changepres and multi-domain cognitive performance in this setting. We aimed to investigate correlations between volume changes in parietal structures and visuospatial performance in temporal lobe epilepsy patients. we performed a cross-sectional study comparing global and regional brain volume data from 34 temporal lobe epilepsy patients and 30 healthy controls. 3D T1-weighted sequences were obtained on a 3.0 T magnet, and data were analyzed using age and sex-adjusted linear regression models. Global and regional brain volumes and cortical thickness in patients were correlated with standardized visual memory, visuoperceptual, visuospatial, and visuoconstructive parameters obtained in a per-protocol neuropsychological assessment. temporal lobe epilepsy patients had smaller volume fractions of the deep gray matter structures, putamen and nucleus accumbens, and larger cerebrospinal fluid volume fraction than controls. Correlations were found between: 1) visual memory and precuneus and inferior parietal cortical thickness; 2) visuoperceptual performance and precuneus and supramarginal white matter volumes; 3) visuospatial skills and precuneus, postcentral, and inferior and superior parietal white matter volumes; 4) visuoconstructive performance and inferior parietal white matter volume. Brain volume loss is widespread in temporal lobe epilepsy. Volumetric reductions in parietal lobe structures were associated with visuoperceptual cognitive performance., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A secondary analysis of a prospective multicenter cohort was performed in six intensive care units (ICU) in four European countries (France, Greece, Spain and Turkey). The main objective was to identify factors associated with ventilator-associated events (VAEs) in adults who underwent mechanical ventilation (MV) ≥ 48 h. Secondary objectives were to identify: variables influencing VAE in the subpopulation with endotracheal intubation and in those subjects who were ventilated > 7 days. Subjects who had undergone MV ≥ 48 h were included. In subjects with multiple episodes of MV, only the first one was eligible. The adult definitions for VAEs were adjusted to the 2015 update of the CDC's 2013 National Healthcare Safety Network Association. Factors associated with VAE were estimated through multivariate Cox proportional hazards analysis. Among 163 adults (42 tracheostomies), 76 VAEs (34.9 VAEs/1,000 ventilator-days) were documented: 9 were Ventilator-Associated Conditions (VAC) and 67 Infection-related Ventilator-Associated Complications (IVAC)-plus (9 only IVAC and 58 Possible Ventilator-Associated Pneumonia). VAEs developed after a median of 6 days (interquartile range: 4-9). VAEs were independently associated with long-acting sedative/analgesic drugs (Hazard Ratio [HR]: 4.30), selective digestive decontamination (SDD) (HR: 0.38), and surgical/trauma admission (HR: 2.30). Among 116 subjects with endotracheal tube, SDD (HR: 0.21) and surgical/trauma admission (HR: 3.11) remained associated with VAE. Among 102 subjects ventilated >7 days, only long-acting sedative/analgesic agents (HR: 8.69) remained independently associated with VAE. In summary, SDD implementation and long-acting analgesic/sedative agents restriction prescription may prevent early and late VAEs, respectively. Bundles developed to prevent VAEs should include these two interventions.

A hyperthermophilic and thermostable xylanase of 82 kDa (TtXynA) was purified from the culture supernatant of T. terrestris Co3Bag1, grown on carboxymethyl cellulose (CMC), and characterized biochemically. TtXynA showed optimal xylanolytic activity at pH 5.5 and at 85 °C, and retained more than 90% of its activity at a broad pH range (4.5-10). The enzyme is highly thermostable with a half-life of 23.1 days at 65 °C, and active in the presence of several metal ions. Circular dichroism spectra strongly suggest the enzyme gains secondary structures when temperature increases. TtXynA displayed higher substrate affinity and higher catalytic efficiency towards beechwood xylan than towards birchwood xylan, oat-spelt xylan, and CMC. According to its final hydrolysis products, TtXynA displays endo-/exo-activity, yielded xylobiose, an unknown oligosaccharide containing about five residues of xylose and a small amount of xylose on beechwood xylan. Finally, this report represents the description of the first fungal hyperthermophilic xylanase which is produced by T. terrestris Co3Bag1. Since TtXynA displays relevant biochemical properties, it may be a suitable candidate for biotechnological applications carried out at high temperatures, like the enzymatic pretreatment of plant biomass for the production of bioethanol.

Chitosan/poly(DL-lactide-co-glycolide) (Ch/DL PLG) composite scaffolds were fabricated by freeze-drying lyophilization, and were evaluated and compared for use as a bone regeneration scaffold through measurements of the compression mechanical properties of the porous scaffolds. Also, In vitro cell culture of Sprague-Dawley rat's osteoblasts were used to evaluate the phenotype expression of cells in the scaffolds, characterizing the cellular adhesion, proliferation and alkaline phosphatase activity. The gene expression of osteocalcin, sialoprotein, alkaline phosphatase, Type I collagen and TGFβ1 were confirmed in the samples; moreover, it was confirmed, the mineralization by IR spectra and EDS analysis. Our results thus show that Ch/DL PLG scaffolds are suitable for biological applications.

In order to evaluate the effect of protein supplementation on the productive and reproductive performance of heifers, 45 Bos indicus x Bos taurus heifers, 673 +/- 146 days of age and weighing about 340 kg, were divided into two groups. The control group (n = 23) continued without supplementation, but the supplemented group (SG; n = 22) received concentrate at a rate of 1% BW kg per day. Animals were adapted to the concentrate over a 15-day period and then supplemented for 30 days, after which estrus was synchronized using a progesterone implant. Back fat thickness (BFT) was assessed by ultrasound. The SG had better average daily weight gain than the nonsupplemented group (0.63 +/- 0.16 vs. 0.51 +/- 0.13 kg/day, P < 0.05) and tended to show a better percentage ovulation (P < 0.10, 77% vs. 57%, respectively). However, this tendency was not reflected in the final pregnancy rates. No differences were observed between groups in dry matter intake and body condition scores. SG with a high BFT (>0.70 cm) showed a better ovulation percentage than those with low BFT (<0.69 cm; P < 0.01). Additionally, the pregnancy rate of supplemented heifers with high BFT tended to be better than heifers with low BFT in this same group (67% vs. 30%, respectively, P < 0.10). It is concluded that protein supplementation improved reproductive performance and that ultrasonography to measure BFT may be used to estimate reproductive performance.

With the objective of evaluating the effect of methionine supplementation prior to a breeding program, thirty one heifers (Bos taurus x Bos indicus) were used averaging 386 +/- 29 days of age and a mean body weight of 402.6 +/- 28 kg. Fifteen of the animals received a supplement (SG) during 45 days with molasses-urea mixture (2 kg molasses + 407 g urea/head/day), plus 10 g of ruminally protected methionine. The other sixteen heifers did not receive supplement (CG). Fecal and pastures samples were collected to assess dry herbage intake and digestibility. Serial ultrasound measurements from the ovary were performed in both groups to evaluate follicular dynamics. The heifers were categorized according to their follicular size and presence of a CL. Forage intake and dry matter digestibility were reduced (P < 0.05) and body condition tended to improve (P = 0.07) in the supplemented heifers, however, total intake, final weight, daily gain and dorsal back fat were not affected. After the supplementation period, the percentage of females in the categories < 3 mm and 3 to < 6 mm, was greater (P < 0.05) in CG (25% and 43.7%) that in SG (0% and 26.6%) but in the follicle category of > or = 9 mm, the percentage of animals was 60% in SG and 18.8% in CG (P < 0.05). The percentage of ovulation for the SG and CG was 86.7% and 62.5%, respectively (P < 0.05). The combination of supplementation with methionine-urea and molasses at the end of the dry season and the anticipated onset of the rainy season favored the establishment of ovarian activity and follicular dynamics.

Fifty-eight nursing Zebu cows averaging 5922 days postpartum were used to evaluate the early embryonic development by ultrasound under a natural mating system (bulls A to F). Three consecutive mating periods of 21 days were established. Sixty two percent of the animals were diagnosed as pregnant (36/58). During the first period (AB) 76% (27/36) of the animals become pregnant, 17% (6/36) during the second (CD) and 9% (3/36) in the last mating period (EF). Sixty two percent of the animals were true positives (animals found pregnant diagnosed by ultrasound (US), and conforming with the embryonic scale proposed by Rosiles et al. (2006); 12% (n = 7) of false negatives (pregnant cows by US but not conforming with the scale); 2% (n = 1) of false positives (pregnant cows, evaluated with US and conforming with the embryonic scale but not pregnant at the end of the study); and a 26% (n = 15) of true negatives (not pregnancy evaluated with US). The sensitivity of the test was 97%, with a specificity of 68% with a positive predictive value of 83% and a negative predictive value of 6%. Relation between the measuring scale of embryo development and the results obtained by ultrasonography was k = 0.69. No significant correlation were observed between body condition score (BCS) evaluation and body fat (BF) measurement at any of the three evaluations performed after mating, however, measurements of BCS and BF among time showed a positive correlation (0.48 P < 0.05, 0.29, P < 0.07, respectively) from the beginning of the evaluation period to the end of the trial. Ultrasonography to monitor embryonic development to determine the early establishment of pregnancy in natural mating reproductive programs can be a valuable technique to monitor reproductive efficiency.

In order to evaluate the reproductive effect of a rotational breeding system, the pregnancy rate of 69 Zebu cows was assessed, 32 late postpartum (211 +/- 93 days postpartum, LP) and 37 early postpartum (averaging 63 +/- 8 days after calving, EP). In the LP group, 60% (19/32) were cycling before exposure to the bulls but only 38% (14/37) in the EP group. The two groups were dissimilar from the start (p < 0.05). The cows were exposed in a rotational breeding system, with six Brahman bulls with previous sexual experience paired off in three groups (A-B, C-D and E-F). The cows were exposed to each pair of bulls for a period of 3 weeks, with one week in between each period, when the females were without the presence of a male. In the LP group, the pair of bulls A B obtained a pregnancy rate of 72% (23/32), whereas for bulls C-D the pregnancy rate was 33% (3/9) and for bulls E-F the pregnancy rate was 67% (4/6). In contrast, for the EP cows, bulls A-B obtained a pregnancy rate of 32% (12/37), bulls C-D a pregnancy rate of 67% (12/18) and for bulls E-F a pregnancy rate of 55% (6/11). The percentage pregnancy obtained using the pair of bulls A-B differed (p < 0.05) between LP and EP, whereas for bulls C-D and E-F it was similar. The pregnancy rate was different (p < 0.05) in the first 3 weeks of mating for the LP group, the highest number of cows becoming pregnant during the first 3 weeks of the study. In contrast, the highest number of pregnancies in EP occurred evenly during the last 6 weeks. This study suggests that the reproductive performance of pairs of bulls in a 9-week rotational programme with the overall pregnancy rate is similar (94% in the LP and 81% in the EP). However, the time taken for the females to become pregnant, and hence the performance of the bulls, is related to the average number of days postpartum for the cows.

Rapid development of labeling chemistry and generation of new chemical entities for biologic interactions via combinatorial chemistry and high throughput screening gives great potential for the development of new positron emission tomography (PET) tracer candidates. It must, however, be realized that a large fraction of these candidates will fail to characterize the desired biochemistry in vivo due to undesirable properties that are not relevant to providing a specific signal in vitro. A full characterization of a PET tracer is a lengthy and expensive procedure, and it is necessary to establish confidence via a number of assays that a tracer will provide useful data in the target species (generally human). These assays should also serve as a background to choose or to reject a tracer at an early time point, conserving valuable resources and time. Autoradiography performed as an ex vivo binding technique or as ex vivo recording of in vivo tracer distribution are, in this respect, very important tools. Autoradiography binding methods allow a range of frozen tissues to be sectioned and incubated with the PET tracer, and with due caution and controls with selective blockade of binding, quantitative values can be obtained with respect to tracer binding and its regional distribution. The method is easy to learn and set up, and should be included in all PET research and development labs. Ex vivo autoradiography of selected organs or whole animals gives qualitative images of a tracer's distribution with high resolution and is especially valid for 18F-labeled tracers. When tracer administration is not limited by mass due to specific radioactivity, 11C-tracers can also be readily used. This method is attractive to use as a complement to small animal imaging due to its high resolution and anatomical correlate. Living slice autoradiography is a more cumbersome method, but has an advantage of utilizing live tissue that retains certain metabolic functions. The use of these different methods in the validation of tracers and for supplying complementary information is illustrated.

Nigericin is a monocarboxylic polyether molecule described as a mobile K+ ionophore unable to transport Li+ and Cs+ across natural or artificial membranes. This paper shows that the ion carrier molecule forms complexes of equivalent energy demands with Li+, Cs+, Na+, Rb+, and K+. This is in accordance with the similar values of the complex stability constants obtained from nigericin with the five alkali metal cations assayed. On the other hand, nigericin-alkali metal cation binding isotherms show faster rates for Li+ and Cs+ than for Na+, K+, and Rb+, in conditions where the carboxylic proton does not dissociate. Furthermore, proton NMR spectra of nigericin-Li+ and nigericin-Cs+ complexes show wide broadenings, suggesting strong cation interaction with the ionophore; in contrast, the complexes with Na+, K+, and Rb+ show only clear-cut chemical shifts. These latter results support the view that nigericin forms highly stable complexes with Li+ and Cs+ and contribute to the explanation for the inability of this ionophore to transport the former cations in conditions where it catalyzes a fast transport of K+ greater than Rb+ greater than Na+.

At pH 4.0, greater than 10(-7) M nigericin was found capable of conducting net charge transfer across bimolecular lecithin membranes, with a stoichiometry of three uncharged ionophore moieties per cation. At neutral or alkaline pH, nigericin catalyzed the transfer of net charge through dimer forms. In agreement with these results, quantitative analysis of nigericin-potassium complexes formed at pH 4.0 showed a 3:1 ratio, and a 2:1 ratio at neutral or alkaline pH. A 1:1 stoichiometry was observed when the ionophore complex was not transferred from methanol-water to chloroform. Moreover, 1H-NMR spectra of nigericin-cation complexes formed at pH 4.0, displayed clear-cut chemical shift variations different to those observed at neutral or alkaline pH. Thus, it is apparent that acid pH causes a transition from dimeric to trimeric forms of nigericin-cation complexes. The membrane conductance increased up to ten times when negatively charged phosphatidyl glycerol was used, while the conductance decreased in positively charged cetylpyridinium containing membranes at pH 4.0. These results suggest that the nigericin-K+ oligomeric complex is positively charged. In this respect, pKa values around 8.0 were obtained for the nigericin carboxylate group in media of different dielectric constant, indicating that this chemical group is undissociated under these conditions. Moreover, the values for the complex formation constants as well as the delta G values calculated for the dimers and trimers indicated that such ionophore cation oligomeric complexes are thermodynamically stable.