Marine collagen scaffolds and photobiomodulation on bone healing process in a model of calvaria defects.

INTRODUCTION: Collagen from marine esponges has been used as a promising material for tissue engineering proposals. Similarly, photobiomodulation (PBM) is able of modulating inflammatory processes after an injury, accelerating soft and hard tissue healing and stimulating neoangiogenesis. However, the effects of the associated treatments on bone tissue healing have not been studied yet. In this context, the present study aimed to evaluate the biological temporal modifications (using two experimental periods) of marine sponge collagen or sponging (SPG) based scaffold and PBM on newly formed bone using a calvaria bone defect model. MATERIAL AND METHODS: Wistar rats were distributed into two groups: SPG or SPG/PBM and euthanized into two different experimental periods (15 and 45 days post-surgery). A cranial critical bone defect was used to evaluate the effects of the treatments. Histology, histomorfometry and immunohistological analysis were performed. RESULTS: Histological findings demonstrated that SPG/PBM-treated animals, 45 days post-surgery, demonstrated a higher amount of connective and newly formed bone tissue at the region of the defect compared to CG. Notwithstanding, no difference among groups were observed in the histomorphometry. Interestingly, for both anti-transforming growth factor-beta (TGF-ß) and anti-vascular endothelial growth factor (VEGF) immunostaining, higher values for SPG/PBM, at 45 days post-surgery could be observed. CONCLUSION: It can be concluded that the associated treatment can be considered as a promising therapeutical intervention.

Phylogeny, Distribution, and Pathogenicity of Lasiodiplodia Species Associated With Cankers and Dieback Symptoms of Persian Lime in Mexico.

Persian lime (Citrus latifolia Tan.) is an important and widely cultivated fruit crop in several regions of Mexico. In recent years, severe symptoms of gummosis, stem cankers, and dieback were detected in the Persian lime-producing region in the states of Veracruz and Puebla, Mexico. The aims of this study were to identify the species of Lasiodiplodia associated with these symptoms, determine the distribution of these species, and test their pathogenicity and virulence on Persian lime plants. In 2015, symptomatic samples were collected from 12 commercial Persian lime orchards, and 60 Lasiodiplodia isolates were obtained. Fungal identification of 32 representative isolates was performed using a phylogenetic analysis based on DNA sequence data of the internal transcribed spacer region and part of the translation elongation factor 1-α and ß-tubulin genes. Sequence analyses were carried out using the Maximum Likelihood and Bayesian Inference methods. Six Lasiodiplodia species were identified as Lasiodiplodia pseudotheobromae, Lasiodiplodia theobromae, Lasiodiplodia brasiliense, Lasiodiplodia subglobosa, Lasiodiplodia citricola, and Lasiodiplodia iraniensis. All Lasiodiplodia species of this study are reported for the first time in association with Persian lime in Mexico and worldwide. L. pseudotheobromae (46.9% of isolates) was the most frequently isolated species followed by L. theobromae (28.1%) and L. brasiliense (12.5%). Pathogenicity on Persian lime young plants using a mycelial plug inoculation method showed that all identified Lasiodiplodia species were able to cause necrotic lesions and gummosis, but L. subglobosa, L. iraniensis, and L. pseudotheobromae were the most virulent.

Sensory profile development of Oaxaca cheese and relationship with physicochemical parameters.

A sensory profile of Oaxaca cheese was developed. To represent both industrial and artisanal Oaxaca cheese, 3 types of cheese were manufactured under controlled conditions: 2 with pasteurized milk using a mesophilic lactic acid bacteria culture (Lactococcus lactis ssp. lactis and L. lactis ssp. cremoris) and a thermophilic lactic acid bacteria culture (Streptococcus salivarius ssp. thermophilus), and a third with naturally acidified raw milk. The cheeses were evaluated by a panel of 11 trained judges. Additionally, chemical composition and instrumental color parameters were determined, an instrumental texture profile analysis was performed, and volatile compounds were identified by solid-phase microextraction coupled with gas chromatography/mass spectrometry. The sensory profile developed includes 43 descriptors, of which 13 are discriminant among these 3 cheese types. Descriptors include visual attribute waxy; tactile (manual) attributes moist and oily; orthonasal aroma attributes empyreumatic and cow; basic taste attribute salty; mouth texture attributes chewable, gummy, adherent, fibrous, moist, and fatty; and auditory attribute squeaky. A strong correlation was found between specific sensory data and physicochemical parameters measured by instrumental and chemical methods.

Genomic prediction in biparental tropical maize populations in water-stressed and well-watered environments using low-density and GBS SNPs.

One of the most important applications of genomic selection in maize breeding is to predict and identify the best untested lines from biparental populations, when the training and validation sets are derived from the same cross. Nineteen tropical maize biparental populations evaluated in multienvironment trials were used in this study to assess prediction accuracy of different quantitative traits using low-density (~200 markers) and genotyping-by-sequencing (GBS) single-nucleotide polymorphisms (SNPs), respectively. An extension of the Genomic Best Linear Unbiased Predictor that incorporates genotype × environment (GE) interaction was used to predict genotypic values; cross-validation methods were applied to quantify prediction accuracy. Our results showed that: (1) low-density SNPs (~200 markers) were largely sufficient to get good prediction in biparental maize populations for simple traits with moderate-to-high heritability, but GBS outperformed low-density SNPs for complex traits and simple traits evaluated under stress conditions with low-to-moderate heritability; (2) heritability and genetic architecture of target traits affected prediction performance, prediction accuracy of complex traits (grain yield) were consistently lower than those of simple traits (anthesis date and plant height) and prediction accuracy under stress conditions was consistently lower and more variable than under well-watered conditions for all the target traits because of their poor heritability under stress conditions; and (3) the prediction accuracy of GE models was found to be superior to that of non-GE models for complex traits and marginal for simple traits.

Biological parameters of interbreeding subspecies of Meccus phyllosomus (Hemiptera: Reduviidae: Triatominae) in western Mexico.

Understanding the biological parameters of some triatomine subspecies of Meccus phyllosomus (Burmeister) is a crucial first step in estimating the epidemiological importance of this group. Biological parameters related to egg eclosion, egg-to-adult development time, number of blood meals to moult, percentage of females at the end of the cycle, number of laid eggs, and the accumulative mortality for each instar of three M. phyllosomus subspecies [Meccus phyllosomus pallidipennis (Stål), Meccus phyllosomus longipennis (Usinger), and Meccus phyllosomus picturatus (Usinger)] as well as their laboratory hybrids were evaluated and compared. No significant differences (P > 0.05) were recorded among the experimental hybrids (M. p. longipennis × M. p. pallidipennis, M. p. longipennis × M. p. picturatus, M. p. pallidipennis × M. p. picturatus) and reciprocal cohorts. In five of the six studied parameters (egg eclosion, egg-to-adult development time, number of blood meals to moult, number of laid eggs and accumulative mortality), with the exception of the non-significant percentage of females obtained among all the studied cohorts, at least one of the parental cohorts in each set of crosses exhibited better fitness results than by those of their hybrid descendants. The lack of hybrid fitness in our study indicates the maintenance of reproductive isolation of parental genotypes. Moreover, the results lead us to propose that an incipient speciation process by distance is currently developing among the three studied subspecies, increasing the differences between them that modify the transmission efficiency of Trypanosoma cruzi to human beings in Mexico.

Percolation of straight slots on a square grid.

This work is devoted to the emergence of a connected network of slots (cracks) on a square grid. Accordingly, extensive Monte Carlo simulations and finite-size scaling analysis have been conducted to study the site percolation of straight slots with length l measured in the number of elementary cells of the grid with the edge size L. A special focus was made on the dependence of the percolation threshold p_{C}(l,L) on the slot length l varying in the range 1≤l≤L-2 for the square grids with edge size in the range 50≤L≤1000. In this way, we found that p_{C}(l,L) strongly decreases with increase of l, whereas the variations of p_{C}(l=const,L) with the variation of ratio l/L are very small. Consequently, we acquire the functional dependencies of the critical filling factor and percolation strength on the slot length. Furthermore, we established that the slot percolation model interpolates between the site percolation on square lattice (l=1) and the continuous percolation of widthless sticks (l→∞) aligned in two orthogonal directions. In this regard, we note that the critical number of widthless sticks per unit area is larger than in the case of randomly oriented sticks. Our estimates for the critical exponents indicate that the slot percolation belongs to the same universality class as standard Bernoulli percolation.

Concordance between freehand SPECT and conventional scintigraphy for sentinel lymph node detection in breast cancer.

INTRODUCTION: Freehand SPECT can be a useful imaging technique for preoperative planning of sentinel lymph node biopsy (SLNB) as it allows localization of the sentinel node by 3D and real-time tomographic imaging and determines its depth after a few minutes of scanning. The aim of the study was to evaluate the correlation between the number of detected SNs between freehand SPECT images and lymphoscintigraphy (LS). MATERIALS AND METHODS: 100 patients with a diagnosis of invasive breast cancer and no clinical evidence of lymph node involvement prospectively underwent SLNB. The preoperative study included freehand SPECT imaging at 15min after injection and LS imaging at 25 and 60-90min after injection (early and late). The observed agreement was analyzed and a concordance study was performed between the number of SNs detected with freehand SPECT and LS. RESULTS: The observed agreement in the detection of SNs between freehand SPECT and early LS was 72%; between freehand SPECT and late LS was 85%; and between early and late LS was 87%. In the concordance study, there was moderate concordance between freehand SPECT and early LS (kappa coefficient: 0.42); moderate-high concordance between freehand SPECT and late LS (kappa coefficient: 0.60); and moderate-high concordance between early and late LS (kappa coefficient: 0.70), with no significant differences between them (p-value=0.16). CONCLUSION: Freehand SPECT showed a moderate-high concordance with conventional imaging studies and could be a valid alternative for the presurgical study of SLNB in breast cancer.

Competitive adsorption of dyes and heavy metals on zeolitic structures.

The adsorption of Acid blue 25, basic blue 9, basic violet 3, Pb(2+), Ni(2+), Zn(2+) and Cd(2+) ions has been studied in single and dye-metal binary solutions using two mineral materials: Clinoptilolite (CL) and ER (Erionite). These zeolites were characterized by FT-IR spectroscopy; potentiometric titration and nitrogen adsorption isotherms at 77 K to obtain their textural parameters. Results indicated that ER has an acidic character and a high specific surface (401 m(2) g(-1)) in contrast with the zeolite CL (21 m(2) g(-1)). Surprisingly, the removal of dyes was very similar for the two zeolites and they showed a considerable selectivity by the basic dyes in comparison with the acid dyes. In the case of heavy metals, ER was more effective in the adsorption process showing a selectivity of: Pb(2+) > Ni(2+) > Zn(2+) > Cd(2+). In the multicomponent adsorption experiments an antagonistic effect was observed in the removal of basic dyes and heavy metals. Particularly, the adsorbed amount of basic violet 3 decreased more significantly when the heavy metals are presents in contrast with the basic blue 9.

Progress and current utility of radiomics in PET/CT study of non-metastatic breast cancer: A systematic review.

AIM: To synthesize the current evidence of the usefulness of radiomics in PET/CT image analysis in local and locally advanced breast cancer. Also, to evaluate the methodological quality of the radiomic studies published. METHODS: Systematic review of articles in different databases until 2021 using the terms "PET", "radiomics", "texture", "breast". Only articles with human data and that included a PET image were included. Studies with simulated data and with less than 20 patients were excluded. Were extracted sample size, radiotracer used, imaging technique, and radiomics characteristics from each article. The methodological quality of the studies was determined using the QUADAS-2 tool. RESULTS: 18 articles were selected. The retrospective design was the most used. The most studied radiomic characteristic was SUVmax. Several radiomic parameters were correlated with tumor characterization, and tumor heterogeneity proved useful for predicting disease course and response to treatment. Most articles showed a high risk of bias, mainly from the patient selection. CONCLUSIONS: A high probability of bias was observed in most of the published articles. Radiomics is a developing field and more studies are needed to demonstrate its usefulness in routine clinical practice. The QUADAS-2 tool allows critical assessment of the methodological quality of the available evidence. Despite its limitations, radiomics is shown to be an instrument that can help to achieve personalized oncologic management of breast cancer.

Superior pubic ramus fixation with titanium elastic nails-surgical technique.

Superior pubic rami fractures are commonly associated with a posterior pelvic ring disruption. It has been shown that fixing both the anterior pelvic arch and the posterior ring increases stability and enhances clinical results. Several techniques for fixing the superior pubic rami exist, and multiple studies showed that minimally invasive methods decrease wound-related complications, with the advantage of preserving soft tissues. We describe a surgical procedure to treat simple pubic rami fractures associated with posterior pelvic ring disruptions by placing an intramedullary elastic titanium nail (TEN). We propose this technique as an alternative fixation method for superior pubic rami fractures.

Las fracturas de la rama superior del pubis se asocian con frecuencia a una alteración del anillo pélvico posterior. Se ha demostrado que la fijación tanto del arco pélvico anterior como del anillo posterior aumenta la estabilidad y mejora los resultados clínicos. Existen varias técnicas para fijar la rama superior del pubis, y múltiples estudios han demostrado que los métodos mínimamente invasivos disminuyen las complicaciones relacionadas con la herida, con la ventaja de preservar los tejidos blandos. Describimos un procedimiento quirúrgico para tratar fracturas simples de la rama púbica asociadas a disrupciones del anillo pélvico posterior mediante la colocación de un clavo intramedular elástico de titanio (TEN). Proponemos esta técnica como método de fijación alternativo para las fracturas superiores de la rama púbica.

Bioglass/collagen scaffolds combined with bone marrow stromal cells on bone healing in an experimental model in cranial defects in rats.

This study aimed to develop bone regenerative therapeutic strategies, based on the addition of bone marrow stromal cells (BMSC) on bioglass/collagen (BG/COL) scaffolds. For this purpose, an in vivo study was conducted using tissue response of the BG/COL scaffolds combined with BMSC in a critical-size defects. Wistar rats were submitted to the surgical procedure to perform the cranial critical size bone defects and distributed in four groups (20 animals per group): Control Group (CG) (rats submitted to the cranial bone defect surgery without treatment), Bioglass Group (BG) (rats treated with BG), BG/COL Group (rats treated with BG/COL) and Bioglass/Collagen and BMSC Group (BG/COL/BMSC) (rats treated with BG/COL scaffolds enriched with BMSCs). Animals were euthanized 15 and 30 days after surgery. Scanning electron microscopy, histopathological and immunohistochemistry analysis were used. SEM analysis demonstrated that porous scaffolds were obtained, and Col fibers were successfully impregnated to BG matrices. The implantation of the BMSC on BG/COL based scaffolds was effective in stimulating newly bone formation and produced an increased immunoexpression of markers related to the bone repair. These results highlight the potential of BG/COL scaffolds and BMSCs to be used as a therapeutic approach for bone regeneration.

Transcriptional regulation of the assT-dsbL-dsbI gene cluster in Salmonella enterica serovar Typhi IMSS-1 depends on LeuO, H-NS, and specific growth conditions.

The assT gene encodes an arylsulfate sulfotransferase, an enzyme that catalyzes sulfuryl transfer from phenolic sulfate to a phenolic acceptor. In Salmonella enterica serovar Typhi IMSS-1, the assT gene is located upstream of the dsbL and dsbI genes, which are involved in a disulfide bond formation required for its activation. The assT-dsbL-dsbI gene cluster forms an operon transcribed by a LeuO-dependent promoter, in rich medium A (MA). Interestingly, in the absence of cloned leuO and in a ΔleuO background, two transcription start sites were detected for assT and two for dsbL-dsbI in minimal medium. The H-NS nucleoid protein repressed the expression of the assT-dsbL-dsbI LeuO-dependent operon, as well as of the assT transcriptional units. Thus, the expression of the assT-dsbL-dsbI gene cluster depends on the global regulatory proteins LeuO and H-NS, as well as on specific growth conditions.

Comparative dissolution profiles of two anti-emetic delayed release dosage forms of doxylamine and pyridoxine: Xonvea® tablets vs. Cariban® capsules.

OBJECTIVE: Nausea and vomiting of pregnancy is a common disease that affects many women suffering from mild to severe symptoms. Amongst the different treatments, a fixed dose combination of doxylamine and pyridoxine has been proven safe and effective although the mechanism of action is not well established. There are different pharmaceutical dosage forms in the European market. The objective of this study was to compare the characteristics of a capsule formulation, Cariban® and a tablet formulation, Xonvea® to evaluate the potential impact of their release profiles on their onset of action. MATERIALS AND METHODS: 10 mg/10 mg of doxylamine succinate/pyridoxine hydrochloride capsules (Cariban®) and tablets (Xonvea®) were used as reference materials. Appearance, mass, composition, and in vitro dissolution profiles were compared. Bibliographic data from 4 pharmacokinetic studies of Xonvea® and 1 pharmacokinetic study of Cariban® was reviewed. RESULTS: In vitro dissolution studies showed significant differences in dissolution profiles of tablets and capsules. The later exhibiting some release of both drug substances in acid conditions followed by a non-complete release after a total of 3 hours while the tablets demonstrated gastro-resistant properties and rapid API release in about 20-30 minutes after the acid stage. Comparison of PK data showed greater Cmax for pyridoxine. CONCLUSIONS: At pH 6.8, complete and faster release of the fixed dose combination for Xonvea® gastro-resistant tablets compared to Cariban® capsules could possibly explain the greater Cmax observed in vivo for the tablet's formulation. This could translate into faster onset of action and relief of nausea for pregnant women taking the tablets vs. the capsules.

GPIbα-vWF rolling under shear stress shows differences between type 2B and 2M von Willebrand disease.

Both type 2B and type 2M von Willebrand disease result in bleeding disorders; however, whereas type 2B has increased binding affinity between platelet glycoprotein Ibα and von Willebrand factor (vWF), type 2M has decreased binding affinity between these two molecules. We used R687E type 2B and G561S type 2M vWF-A1 mutations to study binding between flowing platelets and insolubilized vWF mutants. We measured rolling velocities, mean stop times, and mean go times at 37°C using high-speed video microscopy. The rolling velocities for wt-wt interactions first decrease, reach a minimum, and then increase with increasing shear stress, indicating a catch-slip transition. By changing the viscosity, we were able to quantify the effects of force versus shear rate for rolling velocities and mean stop times. Platelet interactions with loss-of-function vWF-A1 retain the catch-slip bond transition seen in wt-wt interactions, but at a higher shear stress compared with the wt-wt transition. The mean stop time for all vWF-A1 molecules reveals catch-slip transitions at different shear stresses (gain-of-function vWF-A1 < wt vWF-A1< loss-of-function vWF-A1). The shift in the catch-slip transition may indicate changes in how the different mutants become conformationally active, indicating different mechanisms leading to similar bleeding characteristics.

Biocompatibility of alendronate-loaded acrylic cement for vertebroplasty.

This paper reports a biological evaluation of a non-resorbable acrylic cement loaded with alendronate for the treatment of osteoporotic vertebral compression fractures. The cement formulation was based on polymethyl methacrylate and acrylic monomers; one of these had covalently linked vitamin E residues. The same cement in the absence of alendronate was used as a control. The setting of the charged cement presented a maximum polymerization temperature of 44°C, a setting time of 24 min, a residual monomer content lower than 3 wt.%, a compressive strength of 99±10 MPa and an elastic modulus of 1.2±0.2 GPa. Cytotoxicity studies using human osteoblast cultures revealed that the leachable substances of the alendronate loaded cement collected between 1 and 7 days decreased cell viability to values lower than 80%. However, morphological changes and cellular damage in cells produced by the extracts decreased with the leak time. Cell adhesion and growth on charged cement was significantly lower than on the control. Implantation of the cement paste in the intra-femoral cavity of rabbits showed that initially the osteogenic activity was evident for the cement charged with alendronate, and the osteosynthesis process took place mainly in the trabeculae and was manifested by the presence of a non-mineralised osseous spicule. The interface between material and adjacent bone tissue was initially characterized by a variable fibrous response that in many cases it appeared reduced to thin connective tissue after a 24-week-period.

Increased synthesis of α-tocopherol, paramylon and tyrosine by Euglena gracilis under conditions of high biomass production.

AIMS: To analyse the production of different metabolites by dark-grown Euglena gracilis under conditions found to render high cell growth. METHODS AND RESULTS: The combination of glutamate (5 g l(-1) ), malate (2 g l(-1) ) and ethanol (10 ml l(-1) ) (GM + EtOH); glutamate (7·15 g l(-1) ) and ethanol (10 ml l(-1) ); or malate (8·16 g l(-1) ), glucose (10·6 g l(-1) ) and NH(4) Cl (1·8 g l(-1) ) as carbon and nitrogen sources, promoted an increase of 5·6, 3·7 and 2·6-fold, respectively, in biomass concentration in comparison with glutamate and malate (GM). In turn, the production of α-tocopherol after 120 h identified by LC-MS was 3·7 ± 0·2, 2·4 ± 0·1 and 2 ± 0·1 mg [g dry weight (DW)](-1) , respectively, while in the control medium (GM) it was 0·72 ± 0·1 mg (g DW)(-1) . For paramylon synthesis, the addition of EtOH or glucose induced a higher production. Amino acids were assayed by RP-HPLC; Tyr a tocopherol precursor and Ala an amino acid with antioxidant activity were the amino acids synthesized at higher concentration. CONCLUSIONS: Dark-grown E. gracilis Z is a suitable source for the generation of the biotechnologically relevant metabolites tyrosine, α-tocopherol and paramylon. SIGNIFICANCE AND IMPACT OF THE STUDY: By combining different carbon and nitrogen sources and inducing a tolerable stress to the cell by adding ethanol, it was possible to increase the production of biomass, paramylon, α-tocopherol and some amino acids. The concentrations of α-tocopherol achieved in this study are higher than others reported previously for Euglena, plant and algal systems. This work helps to understand the effect of different carbon sources on the synthesis of bio-molecules by E. gracilis and can be used as a basis for future works to improve the production of different metabolites of biotechnological importance by this organism.

[Quinacrine in the treatment of cutaneous lupus erythematosus: practical aspects and a case series]. / Aspectos prácticos de la quinacrina como tratamiento del lupus eritematoso cutáneo: serie de casos.

Hydroxychloroquine and chloroquine are antimalarials used as first-line treatment of cutaneous lupus. Quinacrine is not often employed by Spanish physicians due to a lack of information about its use and the fact that it is not marketed in Spain. It is effective in monotherapy or in combination therapy with other antimalarials. One of the advantages of quinacrine over chloroquine and hydroxychloroquine is that it does not appear to cause retinal toxicity. Quinacrine is used as second-line therapy in patients with pre-existing eye problems that contraindicate treatment with chloroquine or hydroxychloroquine (after evaluation of which drug has the better risk-benefit relationship), and in combination therapy with other antimalarials inpatients with resistance or only a partial response to chloroquine or hydroxychloroquine. We report 8 cases of patients with cutaneous lupus who received treatment with quinacrine in monotherapy or in combination with others antimalarials. Lesions resolved in 5 patients and improved in 3. Therapy had to be withdrawn in 1 patient due to an exacerbation of his psoriasis.

[Fixation of acetabulum posterior column fracture, arthroscopy assisted]. / Fijación de fractura de columna posterior de acetábulo, asistida por artroscopía.

Arthroscopic surgery of the hip has evolved significantly over the last years, offering an opportunity of treatment in several intra-articular pathologies. Recent methods and instrumental advances have allowed more frequent use of this procedure, with various indications such as: hip pain, acetabular labrum lesions, extraction of foreign bodies, debridement in septic arthritis, pincer impingement, and some extra-articular injuries. Another intra-articular hip pathology that benefits from arthroscopic assistance could be found in the management of simple acetabular fractures. Therefore, this report presents the case of a patient with a posterior column fracture treated with an arthroscopic approach. Arthroscopic techniques for the fixation of intra-articular fractures offer the advantage of a direct visualization of the articular surface, which results in an anatomical reduction. In addition, arthroscopic techniques also present a benefit for intra-articular injuries such as the posterior labral lesion in this case. In simple fractures of the posterior acetabular column with minimum displacement, where percutaneous screw fixation is useful as a definitive fixation method, hip arthroscopy is useful for the reduction process and verifies the extra-articular screw trajectory.

La cirugía artroscópica de la cadera ha evolucionado considerablemente en los últimos años, ofreciendo oportunidad de tratamiento a muchas patologías intraarticulares no reconocidas previamente. Con avances recientes en métodos e instrumentos quirúrgicos, se realiza cada vez más frecuentemente, con indicaciones que incluyen: diagnóstico de pacientes con dolor de cadera, lesiones del labrum acetabular, extracción de cuerpos extraños, desbridamiento en artritis séptica, pinzamiento femoroacetabular y algunos daños extraarticulares. Otra patología intraarticular de la cadera que se beneficia de la asistencia por artroscopía se podría encontrar en el manejo de fracturas acetabulares simples. Reportamos el caso de un paciente con fractura de columna posterior acetabular, tratado vía artroscópica, y los resultados obtenidos. Las técnicas artroscópicas para la fijación de fracturas intraarticulares ofrecen la ventaja de una visualización y reducción superiores de la superficie articular, ya que se hacen mediante observación del foco de fractura, permitiendo una reducción anatómica. Además, las técnicas de reducción artroscópica ofrecen otro beneficio para las lesiones intraarticulares, como en este caso la lesión de labrum posterior. En los trazos simples con poco desplazamiento de las fracturas de columna posterior acetabular, donde la fijación percutánea con tornillos es útil como método de fijación definitiva, la artroscopía de cadera es de utilidad con el fin de asistir durante el proceso de reducción y verificar que el trayecto del tornillo no se encuentre intraarticular.

Unraveling the effects on lithium-ion cathode performance by cation doping M-Li2CuO2 solid solution samples (M = Mn, Fe and Ni).

Cation doping is one of the most dynamic strategies to enhance the electrochemical properties of cathode materials for lithium-ion batteries. Nevertheless, the maximum partial substitution capacity depends on the solubility of each metal ion, and so the formation of impurities is a very common consequence. Thus, the correlation between electrochemical performance and the doping effect is frequently unknown. In this study, the effect of the partial substitution of copper by manganese, iron or nickel in Li2CuO2 is evaluated, as well as the effect on the electrochemical performance of the modified Li2CuO2 samples as lithium ion battery cathode materials. XRD characterization confirmed single phase formation for all samples, and the incorporation of the transition metal in the Li2CuO2 structure was evaluated by XRD profile fitting, EPR and 7Li-NMR. The results showed modifications in intra- and inter-chain interactions, associated with the variations in the Cu-O-Cu bond angle and changes in magnetic order, due to the presence of the doping transition metal. Among all samples, only manganese partial substitution reveals a drastic improvement in the electrochemical stability during the charge/discharge processes even at potentials higher than 3.9 V. It was corroborated that the higher stability is attributed to (i) the increase in the superexchange interactions between the copper sites and manganese, directly modifying lithium diffusivity and electronic conductivity, both inferred from dynamic thermogravimetric analysis for CO2 sorption and conductivity tests, respectively and (ii) the lower propensity to enable O2 evolution during several charge cycles. These results are totally attributed to manganese cation partial substitution, which has a huge impact on the utilization of copper-based materials in real applications.

Acetylation of lysine 40 in alpha-tubulin is not essential in Tetrahymena thermophila.

In Tetrahymena, at least 17 distinct microtubule structures are assembled from a single primary sequence type of alpha- and beta-tubulin heterodimer, precluding distinctions among microtubular systems based on tubulin primary sequence isotypes. Tetrahymena tubulins also are modified by several types of posttranslational reactions including acetylation of alpha-tubulin at lysine 40, a modification found in most eukaryotes. In Tetrahymena, axonemal alpha-tubulin and numerous other microtubules are acetylated. We completely replaced the single type of alpha-tubulin gene in the macronucleus with a version encoding arginine instead of lysine 40 and therefore cannot be acetylated at this position. No acetylated tubulin was detectable in these transformants using a monoclonal antibody specific for acetylated lysine 40. Surprisingly, mutants lacking detectable acetylated tubulin are indistinguishable from wild-type cells. Thus, acetylation of alpha-tubulin at lysine 40 is non-essential in Tetrahymena. In addition, isoelectric focusing gel analysis of axonemal tubulin from cells unable to acetylate alpha-tubulin leads us to conclude that: (a) most or all ciliary alpha-tubulin is acetylated, (b) other lysines cannot be acetylated to compensate for loss of acetylation at lysine 40, and (c) acetylated alpha-tubulin molecules in wild-type cells contain one or more additional charge-altering modifications.