Very low elastic modulus Ti alloys obtained by Laser Directed Energy Deposition to avoid bone resorption in bone implants

The elastic modulus of the cortical bone is below 30 GPa, whereas biomedical titanium implants exhibit an elastic modulus above 100 GPa. This mismatch in the elastic modulus can lead to bone resorption caused by the stress-shielding effect and poor osseointegration of the implant. This study aimed to determine whether the intense fiber texture developed in Laser Directed Energy Deposition of beta-type Ti alloy ingots, results in a significant reduction in the elastic modulus. We demonstrated that laser-deposited beta-type Ti-42Nb (wt%) alloy ingots exhibit anisotropic mechanical properties. A low elastic modulus (below 50 GPa) and a high yield strength (above 700 MPa) were obtained in the building direction because of the intense fiber texture. The novel laser deposited Ti-42Nb alloy also shows excellent biological performance in vitro, which suggests its suitability for biomedical applications.The authors wish to thank the technical staff from Barcelona Research Center in Multiscale Science and Engineering (Universitat Politècnica de Catalunya) and Light Alloys and Surface Treatments Design Centre (Universitat Politècnica de Catalunya) for their technical assistance with the characterization techniques. Technical assistance of Mr. A. Abalde (Universidade de Vigo) is also acknowledged. This research was partially funded by SOADCO S.L. (Escaldes Engordany, Andorra), by the Spanish Government (This publication is part of the TED2021-131721B-I00 project, funded by MCIN/AEI/10.13039/501100011033 and European Union “NextGenerationEU”/PRTR), by Xunta de Galicia (ED431C 2023/25; ED481B-2021-113), by Generalitat de Catalunya (2017 SGR-1165)

Rendimiento y calidad de Avena sativa asociada con Vicia sativa en la región puna del Perú

The study was conducted at the Alpaicayan Experimental Centre, Daniel Alcides Carrión National University, Pasco, Peru, with the objective of determining the forage production and nutritional quality of oats associated with vetch. Forage production was determined in green matter content (GM), dry matter (DM) and percent of dry matter (%DM). For the nutritional value, crude protein (%CP), neutral detergent fibre (%NDF), acid detergent fibre (%ADF), calcium (%Ca) and phosphorus (%P) were determined. The treatments were T-1 (Creole oat, 150 kg/ha), T-2 (Mantaro 15 oat, 110 kg/ha), T-3 (Mantaro 15 oat plus vetch, 110 and 30 kg/ha) and T-4 (creole oat plus vetch, 150 and 30 kg/ha). GM production indicated that T-1 and T-4 were similar but significantly greater than T-2 and T-3 (p<0.05); however, without significant differences in DM production between treatments. T-4 obtained the largest content of %PC, T-2 and T-4 presented greater yields of %NDF and %ADF. T-4 presented the highest content of %P, while there was no difference between treatments for the content of %Ca. It is concluded that the Mantaro 15 + vetch treatment has a better forage production and is of better nutritional quality in relation to the other treatments.El estudio se realizó en el Centro Experimental Alpaicayán, Universidad Nacional Daniel Alcides Carrión, Pasco, Perú, con el objetivo fue determinar la producción forrajera y calidad nutricional de la avena asociada con vicia. Se determinó la producción forrajera en contenidos de materia verde (MV), materia seca (MS) y el porcentaje de materia seca (%MS). Para el valor nutricional se determinaron la proteína cruda (%PC), fibra detergente neutro (%FDN), fibra detergente ácido (%FDA), calcio (%Ca) y fósforo (%P). Los tratamientos fueron T-1 (avena criolla, 150 kg/ha), T-2 (avena Mantaro 15, 110 kg/ha), T- 3 (avena Mantaro 15 más vicia, 110 y 30 kg/ha) y T-4 (avena criolla más vicia, 150 y 30 kg/ha). La producción de MV indicó que T-1 y T-4 fue similar, pero significativamente superior a T-2 y T-3 (p<0.05); sin embargo, sin diferencias significativas en producción de MS entre tratamientos. T-4 obtuvo mayor contenido de %PC, T-2 y T-4 presentaron los mayores rendimientos de %FDN y %FDA. T-4 presentó el mayor contenido de %P, en tanto que no hubo diferencias entre tratamientos para el contenido de %Ca. Se concluye que el tratamiento Mantaro 15 +vicia tiene una mejor producción forrajera y es de mejor calidad nutricional en referencia a los otros tratamientos.

Dissemination of methicillin-resistant Staphylococcus aureus USA300 sequence type 8 lineage in Latin America.

BACKGROUND: Methicillin-resistant Staphylococus aureus (MRSA) is an important nosocomial and community-associated (CA) pathogen. Recently, a variant of the MRSA USA300 clone emerged and disseminated in South America, causing important clinical problems. METHODS: S. aureus isolates were prospectively collected (2006-2008) from 32 tertiary hospitals in Colombia, Ecuador, Peru, and Venezuela. MRSA isolates were subjected to antimicrobial susceptibility testing and pulsed-field gel electrophoresis and were categorized as health care-associated (HA)-like or CA-like clones on the basis of genotypic characteristics and detection of genes encoding Panton-Valentine leukocidin and staphylococcal cassette chromosome (SCC) mec IV. In addition, multilocus sequence typing of representative isolates of each major CA-MRSA pulsotype was performed, and the presence of USA300-associated toxins and the arcA gene was investigated for all isolates categorized as CA-MRSA. RESULTS: A total of 1570 S. aureus were included; 651 were MRSA (41%)--with the highest rate of MRSA isolation in Peru (62%) and the lowest in Venezuela (26%)--and 71%, 27%, and 2% were classified as HA-like, CA-like, and non-CA/HA-like clones, respectively. Only 9 MRSA isolates were confirmed to have reduced susceptibility to glycopeptides (glycopeptide-intermediate S. aureus phenotype). The most common pulsotype (designated ComA) among the CA-like MRSA strains was found in 96% of isolates, with the majority (81%) having a \u3c or =6-band difference with the USA300-0114 strain. Representative isolates of this clone were sequence type 8; however, unlike the USA300-0114 strain, they harbored a different SCCmec IV subtype and lacked arcA (an indicator of the arginine catabolic mobile element). CONCLUSION: A variant CA-MRSA USA300 clone has become established in South America and, in some countries, is endemic in hospital settings

Classification of strengthening exercises of the lower member posterior chain, based on the amplitude of muscular activation in amateur soccer players between 18-25 years

The hamstring injuries are recurrent in the sports disciplines of teams such as football, with rehabilitation being a key point to prevent future alterations. Within this process, the strengthening paradigms are rather empirical, therefore, criteria based on the exercises used are required. In this context, the objective of the present investigation is to classify the strengthening exercises of the posterior lower limb chain, based on the amplitude of muscular activation, in amateur soccer players of the Andrés Bello University (UNAB), for which a non-experimental, descriptive, cross-sectional design. The study population was 30 university students, who were studying from first to fifth year, during the academic period 2017. The participants were summoned to the Laboratory of Rehabilitation Sciences, where after signing the informed consent they had to perform a phase of heating on a cycle ergometer, then the MCIV (maximum voluntary isometric contraction) of the semimembranous, semitendinous, biceps femoral and gluteus maximus muscles was calculated, finally applying a battery of strengthening exercises, which were classified according to the intensity of muscle activation. In relation to this, it was obtained that 8 of the 13 exercises implemented were classified as low intensity (p <0.05), 3 of medium intensity (p <0.05) and 2 of high intensity (p <0.05), while the peak of amplitude of the semimembranous, semitendinous and biceps femoral muscles moved to the right in temporal terms, to the extent that the exercises classified as low, medium and high intensity are compared.Las lesiones de isquiotibiales son recurrentes en disciplinas deportivas de equipos como el fútbol, siendo la rehabilitación un punto clave para prevenir alteraciones futuras. Dentro de este proceso, los paradigmas de fortalecimiento son más bien empíricos, por lo tanto, criterios fundamentados en torno a los ejercicios utilizados son requeridos. Bajo este contexto, el objetivo de la presente investigación fue clasificar los ejercicios de fortalecimiento de la cadena posterior de miembro inferior, en base a la amplitud de activación muscular, en futbolistas amateur de la Universidad Andrés Bello (UNAB), para lo cual se utilizó un diseño no experimental de tipo descriptivo y de corte transversal. La población de estudio, fueron 30 estudiantes universitarios, que estaban cursando de primero a quinto año, durante el periodo académico 2017. Los participantes fueron citados al Laboratorio de Ciencias de Rehabilitación de la UNAB, en donde luego de firmar el consentimiento informado debieron realizar una fase de calentamiento en cicloergómetro, posteriormente se calculó la MCIV (Máxima contracción isométrica voluntaria) de los músculos semimembranoso, semitendinoso, bíceps femoral y glúteo mayor, para finalmente aplicar una batería de ejercicios de fortalecimientos, los cuales fueron clasificados según la intensidad de activación muscular. En relación con esto, se obtuvo que 8 de los 13 ejercicios implementados fueron clasificados de baja intensidad (p<0.05), 3 de mediana intensidad (p<0.05) y 2 de alta intensidad (p<0.05), mientras que el peak de amplitud de los músculos semimembranoso, semitendinoso y bíceps femoral se desplazó a la derecha en términos temporales, en la medida que se comparan los ejercicios clasificados como de baja, media y alta intensidad

Community-associated Methicillin-resistant Staphylococcus aureus, Colombia

Q1Cartas al editor2000-2001To the Editor: Methicillin-resistant Staphylococcus aureus (MRSA) is an established nosocomial pathogen worldwide but more recently has emerged as a highly virulent organism in the community, particularly in the United States (1–3). In Latin America, community-associated MRSA (CA-MRSA) has only been described in the southern area of the continent (Uruguay and Brazil) (4,5). No reports from the Andean region are available. We describe 2 cases of CA-MRSA causing soft-tissue infections (1 severe) in Colombia

Medical imaging: Foundations and scope

Indexación: Scopus; Radalyc.En la actualidad es innegable la utilidad de las diversas modalidades de imagenología médica como apoyo clínico tanto en la generación de diagnósticos de un buen número de enfermedades como en la planeación de tratamientos tendientes a proporcionar una alternativa de solución a las personas que, por una u otra razón, manifiestan algún desequilibrio en su salud. Entre las modalidades imagenológicas que, frecuentemente, se utilizan en el ámbito médico se pueden mencionar: Ultrasonido (US), Resonancia Magnética (MRI), Tomografía Computarizada sencilla (CT) y multicapa (MSCT), Tomografía Computarizada por Emisión de Positrones (PET) y Tomografía Computarizada por Emisión de Fotones simples (SPECT). En este sentido, este artículo tiene como finalidad presentar una descripción ordenada, coherente y sistemática de cada una de las mencionadas modalidades y establecer la vinculación de la MSCT con situaciones clínicas íntimamente relacionadas con la anatomía cardiaca y procesos de hipertensión. La razón por la cual se hace énfasis en la MSCT es debido a que, por una parte, se cuenta con un número importante de bases de datos tanto de sujetos fisiológicos como de sujetos patológicos y, por la otra, que se tiene previsto presentar un conjunto de técnicas computacionales que serán exploradas en el desarrollo de futuras investigaciones en el contexto de aspectos anatómico-cardiológicos que influyen directa o indirectamente en la aparición, desarrollo y prevalencia de procesos hipertensivos.Nowdays, several forms of medical imaging are usefulness in clinical support for both diagnostics diseases generation and treatment planning designed to provide an alternative solution to people who, for one or another reason, manifest an imbalance in your health. Among the imaging modalities that frequently are used in the medical field may include: Ultrasound (US), magnetic resonance imaging (MRI), simple computed tomography (CT) and multilayer computed tomography (MSCT), CT positron emission tomography (PET) Computed tomography and single photon emission (SPECT). In this sense, this article presents an orderly, coherent and systematic description of these modalities and it establishes relationship with the MSCT modality and clinical situations closely related to cardiac anatomy and hypertension processes. The reason emphasis on MSCT is done is because, on the one hand, we have a large number of databases both physiological subjects and pathological subjects and, on the other, we plan to present a set of computational techniques that will be explored in future research, in the context of cardiologic anatomical aspects, with directly or indirectly influence in the emergence, development and prevalence of hypertensive processes.http://www.redalyc.org/articulo.oa?id=5594990700

Monitoring an Alien Invasion: DNA Barcoding and the Identification of Lionfish and Their Prey on Coral Reefs of the Mexican Caribbean

BACKGROUND: In the Mexican Caribbean, the exotic lionfish Pterois volitans has become a species of great concern because of their predatory habits and rapid expansion onto the Mesoamerican coral reef, the second largest continuous reef system in the world. This is the first report of DNA identification of stomach contents of lionfish using the barcode of life reference database (BOLD). METHODOLOGY/PRINCIPAL FINDINGS: We confirm with barcoding that only Pterois volitans is apparently present in the Mexican Caribbean. We analyzed the stomach contents of 157 specimens of P. volitans from various locations in the region. Based on DNA matches in the Barcode of Life Database (BOLD) and GenBank, we identified fishes from five orders, 14 families, 22 genera and 34 species in the stomach contents. The families with the most species represented were Gobiidae and Apogonidae. Some prey taxa are commercially important species. Seven species were new records for the Mexican Caribbean: Apogon mosavi, Coryphopterus venezuelae, C. thrix, C. tortugae, Lythrypnus minimus, Starksia langi and S. ocellata. DNA matches, as well as the presence of intact lionfish in the stomach contents, indicate some degree of cannibalism, a behavior confirmed in this species by the first time. We obtained 45 distinct crustacean prey sequences, from which only 20 taxa could be identified from the BOLD and GenBank databases. The matches were primarily to Decapoda but only a single taxon could be identified to the species level, Euphausia americana. CONCLUSIONS/SIGNIFICANCE: This technique proved to be an efficient and useful method, especially since prey species could be identified from partially-digested remains. The primary limitation is the lack of comprehensive coverage of potential prey species in the region in the BOLD and GenBank databases, especially among invertebrates