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Natural proteins are frequently marginally stable, and an increase in environmental temperature can easily lead to unfolding. As a result, protein engineering to improve protein stability is an area of intensive research. Nonetheless, since there is usually a high degree of structural homology between proteins from thermophilic organisms and their mesophilic counterparts, the identification of structural determinants for thermoadaptation is challenging. Moreover, in many cases, it has become clear that the success of stabilization strategies is often dependent on the evolutionary history of a protein family. In the last few years, the use of ancestral sequence reconstruction (ASR) as a tool for elucidation of the evolutionary history of functional traits of a protein family has gained strength. Here, we used ASR to trace the evolutionary pathways between mesophilic and thermophilic kinases that participate in the biosynthetic pathway of vitamin B1 in bacteria. By combining biophysics approaches, X-ray crystallography, and molecular dynamics simulations, we found that the thermal stability of these enzymes correlates with their kinetic stability, where the highest thermal/kinetic stability is given by an increase in small hydrophobic amino acids that allow a higher number of interatomic hydrophobic contacts, making this type of interaction the main support for stability in this protein architecture. The results highlight the potential benefits of using ASR to explore the evolutionary history of protein sequence and structure to identify traits responsible for the kinetic and thermal stability of any protein architecture.

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Definitive diagnosis of histoplasmosis relies on culture and/or cytology/histopathology; however, these procedures have limited sensitivity and cultures are time-consuming. Antibodies detection by immunodiffusion has low sensitivity in immunocompromised individuals and uses histoplasmin (HMN), a crude antigenic extract, as reagent. Novel protein antigen candidates have been recently identified and produced by DNA-recombinant techniques to obtain standardized and specific reagents for diagnosing histoplasmosis. To compare the analytical performance of novel enzyme-linked immunosorbent assays (ELISAs) for antibodies testing for diagnosing histoplasmosis using different Histoplasma capsulatum antigens as reagents. The H. capsulatum 100 kDa protein (Hcp100), the M antigen and its immunoreactive fragment F1 were produced by DNA-recombinant techniques. Galactomannan was purified from both the yeast and mycelial cell walls (yGM and mGM, respectively). The analytical performance of the ELISA tests for the serological detection of antibodies against these antigens was evaluated and compared with those obtained using HMN as reagent. Antibodies detection by the Hcp100 ELISA demonstrated 90.0% sensitivity and 92.0% specificity, versus 43.3% sensitivity and 95.0% specificity of the M ELISA, 33.3% sensitivity and 84.0% specificity of the F1 ELISA, 96.7% sensitivity and 94.0% specificity of the yGM ELISA, 83.3% sensitivity and 88.0% specificity of the mGM ELISA, and 70.0% sensitivity and 86.0% specificity for the HMN ELISA. In summary, Hcp100 is proposed as the most promising candidate for the serodiagnosis of histoplasmosis. The primary immunoreactive element in HMN proved to be GM rather than the M antigen. Nevertheless, a higher incidence of cross-reactions was noted with GM compared to M.

Hcp100 is a promising serodiagnostic candidate for histoplasmosis, boasting high sensitivity and specificity. Notably, GM, rather than M antigen, emerged as the primary immunoreactive element in HMN, despite a higher incidence of cross-reactions with GM compared to M.

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Mollusk hemocyanins, among the largest known proteins, are used as immunostimulants in biomedical and clinical applications. The hemocyanin of the Chilean gastropod Concholepas concholepas (CCH) exhibits unique properties, which makes it safe and effective for human immunotherapy, as observed in animal models of bladder cancer and melanoma, and dendritical cell vaccine trials. Despite its potential, the structure and amino acid sequence of CCH remain unknown. This study reports two sequence fragments of CCH, representing three complete functional units (FUs). We also determined the high-resolution (1.5 Å) X-ray crystal structure of an "FU-g type" from the CCHB subunit. This structure enables in-depth analysis of chemical interactions at the copper-binding center and unveils an unusual, truncated N-glycosylation pattern. These features are linked to eliciting more robust immunological responses in animals, offering insights into CCH's enhanced immunostimulatory properties and opening new avenues for its potential applications in biomedical research and therapies.

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Rational design of peptides has become a powerful tool to produce self-assembled nanostructures with the ability to catalyze different chemical reactions, paving the way to develop minimalistic enzyme-like nanomaterials. Catalytic amyloid-like assemblies have emerged among the most versatile and active, but they often require additional factors for activity. Elucidating how these factors influence the structure and activity is key for the design. Here, we showed that biologically relevant metal ions can guide and modulate the self-assembly of a small peptide into diverse amyloid architectures. The morphology and catalytic activity of the resulting fibrils were tuned by the specific metal ion decorating the surface, whereas X-ray structural analysis of the amyloids showed ion-dependent shape sizes. Molecular dynamics simulations showed that the metals can strongly affect the local conformational space, which can trigger major rearrangements of the fibrils. Our results demonstrate that the conformational landscape of catalytic amyloids is broad and tunable by external factors, which can be critical for future design strategies.

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BACKGROUND: Peru reports higher levels than other countries in Latin America of resistance to antimicrobials among Gram-positive and Gram-negative bacteria, however data on antibiotic use in Peru are scarce. This study aims to estimate the prevalence and quality of antibiotic prescription in hospitalized patients and to determine the antibiotic susceptibility rates of bacteria causing key bacterial infections. METHODS: We carried out a point prevalence survey of antibiotic prescription at ten public hospitals in nine regions of Peru. Data was collected from patients hospitalized during a 3-week period, with details about antibiotic use, patient information, and antimicrobial susceptibility. RESULTS: 1620 patient charts were reviewed; in 924 cases antibiotics were prescribed (57.0 %, range 45.9-78.9 %). Most of the antibiotics (74.2 %) were prescribed as empirical treatment, only 4.4 % as targeted treatment. For 9.5 % of cases the reason for antibiotic use was unknown. Cephalosporins were the most prescribed (30.0 %), followed by carbapenems (11.3 %). Ninety-four blood cultures were positive for bacterial growth, 48.8 % of the Staphylococcus aureus were methicillin-resistant, among Escherichia coli and Klebsiella pneumoniae, 51.7 % and 72.7 % were resistant to third-generation cephalosporins (3GC), 3.4 % and 18.2 % were resistant to carbapenems, respectively. Among bacteria isolated from urine cultures (n = 639), 43.9 % of E. coli and 49.2 % of K. pneumoniae were resistant to 3GC, and 0.9 % of E. coli and 3.2 % of K. pneumoniae were resistant to meropenem. CONCLUSIONS: The overall proportion of hospitalized patients receiving antibiotics in hospitals from different regions in Peru was high, with only a small proportion receiving targeted treatment. Cephalosporins and carbapenems were the most frequently prescribed antibiotics, reflecting high resistance rates against 3GC and carbapenems in Enterobacterales isolated from blood and urine.

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There is a knowledge gap in the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) causing bloodstream infections (BSIs) in Peru. Through a surveillance study in 13 hospitals of 10 Peruvian regions (2017-2019), we assessed the proportion of MRSA among S. aureus BSIs as well as the molecular typing of the isolates. A total of 166 S. aureus isolates were collected, and 36.1% of them were MRSA. Of note, MRSA isolates with phenotypic and genetic characteristics of the hospital-associated Chilean-Cordobes clone (multidrug-resistant SCCmec I, non-Panton-Valentine leukocidin [PVL] producers) were most commonly found (70%), five isolates with genetic characteristics of community-associated MRSA (CA-MRSA)-SCCmec IV, PVL-producer-(8.3%) were seen in three separate regions. These results demonstrate that hospital-associated MRSA is the most frequent MRSA found in patients with BSIs in Peru. They also show the emergence of S. aureus with genetic characteristics of CA-MRSA. Further studies are needed to evaluate the extension of CA-MRSA dissemination in Peru.

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Surveillance of antimicrobial resistance among gram-negative bacteria (GNB) is of critical importance, but data for Peru are not available. To fill this gap, a non-interventional hospital-based surveillance study was conducted in 15 hospitals across Peru from July 2017 to October 2019. Consecutive unique blood culture isolates of key GNB (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter spp.) recovered from hospitalized patients were collected for centralized antimicrobial susceptibility testing, along with linked epidemiological and clinical data. A total of 449 isolates were included in the analysis. Resistance to third-generation cephalosporins (3GCs) was present in 266 (59.2%) GNB isolates. Among E. coli (n = 199), 68.3% showed 3GC resistance (i.e., above the median ratio for low- and middle-income countries in 2020 for this sustainable development goal indicator). Carbapenem resistance was present in 74 (16.5%) GNB isolates, with wide variation among species (0% in E. coli, 11.0% in K. pneumoniae, 37.0% in P. aeruginosa, and 60.8% in Acinetobacter spp. isolates). Co-resistance to carbapenems and colistin was found in seven (1.6%) GNB isolates. Empiric treatment covered the causative GNB in 63.3% of 215 cases. The in-hospital case fatality ratio was 33.3% (92/276). Pseudomonas aeruginosa species and carbapenem resistance were associated with higher risk of in-hospital death. In conclusion, an important proportion of bloodstream infections in Peru are caused by highly resistant GNB and are associated with high in-hospital mortality.

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Functional foods have recently generated a lot of attention among consumers looking for healthy options. Studies have examined yogurt with carao to increase health benefits and probiotic characteristics. It has been determined that carao fruit and camel milk have high phenolic compound and antioxidant activity concentrations. The objective of this study was to examine if carao (0, 1.3, 2.65, and 5.3 g/L) incorporated into yogurt enhances anti-inflammatory stimulus and antioxidant activity and impacts the physio-chemical and sensory properties of camel milk yogurt. HT-29 cells were used as a model of anti-inflammatory response, including cytokine responses of IL-8 and mRNA production of IL-1ß and TNF-α in gastric digested isolated fraction. In addition, pH, titratable acidity, Streptococcus thermophilus counts and Lactobacillus bulgaricus counts of camel yogurts were examined during the fermentation process in 0, 2.5, 5, and 7 h whereas viscosity, syneresis, and radical scavenging assay evaluations were determined at hour 7. Furthermore, a consumer study was performed. Compared to control samples, the incorporation of carao into yogurts did not lead to a significant (ρ > 0.05) difference in the pH. In contrast, titratable acidity (TA), viscosity, syneresis, and antioxidant capacity significantly increased with the inclusion of 2.65 and 5.3 g/L carao, while 5.3 g/L carao significantly (ρ < 0.05) increased the counts of both bacteria. The inflammatory response of IL-8 and the level of mRNA production of IL-1ß and TNF-α was significantly (ρ < 0.05) lower with 2.65 and 5.3 g/L carao yogurt compared to control camel yogurt. Sensory attributes were not impacted by the addition of 1.3 and 2.65 g/L carao. Carao could be a possible ingredient to consider when improving the nutrition value of yogurt.

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Abstract: The increasing trend and projection for the use of wearable sensors technology in the general population have led to the development of different inertial measurement units (IMU) to monitor activity and motion variables during exercise or sports. This study aims to systematize the practical experience of developing an inertial measurement device to quantify external load in real time for runners. This article shows the installed capacity of Costa Rican higher education institutions to integrate existing sensors available in the international market in a single device to program it and use it for different sport science purposes. Two scientific laboratories joined resources and integrated an interdisciplinary team composed of exercise physiologists, sports scientists, physiotherapists, and electromechanical engineers who globally faced the challenge of creating SafeRun IMU. In this case, an IMU was constructed with great success, capable of quantifying external load variables controlled from a mobile device in real-time. The results showed an acceptable agreement and reliability of the data extracted from the IMU. The information collected from this IMU could be used to control and quantify external load to develop or redirect exercise programming and prescription and prevent overuse injuries or physical overload conditions. This device differs from other existing ones due to its small size and portability, which benefits its commercialization and massification.

Resumen: La creciente tendencia y proyección para el uso de tecnología de sensores portátiles en la población en general ha llevado al desenvolvimiento de diferentes dispositivos de medición inercial, para monitorear las variables de actividad y movimiento durante el ejercicio o los deportes. El objetivo del presente estudio es sistematizar la experiencia práctica de desarrollar un dispositivo de medición inercial, con el fin de cuantificar la carga externa en tiempo real para los corredores. Este artículo demostró la capacidad instalada de las instituciones de educación superior de Costa Rica para integrar los sensores existentes disponibles en el mercado internacional en un solo dispositivo, con el propósito de programarlo y usarlo en diferentes fines de ciencias del deporte. Dos laboratorios científicos unieron esfuerzos e integraron un equipo interdisciplinario compuesto por fisiólogos del ejercicio, científicos del deporte, fisioterapeutas e ingenieros electromecánicos, quienes, de manera global, afrontaron el reto de la creación de la IMU. En este caso, se desarrolló una IMU con gran éxito, capaz de cuantificar las variables de carga externa controladas desde un dispositivo móvil en tiempo real. Los resultados mostraron un nivel de concordancia y fiabilidad aceptable de los datos extraídos de la IMU. La información obtenida de esta IMU podría usarse para controlar y cuantificar la carga externa, con miras a desplegar o redirigir la programación y prescripción de ejercicios, así como con el afán de prevenir lesiones por sobreuso o condiciones de sobrecarga física.

Resumo: A crescente tendência e projeção para o uso da tecnologia de sensores portáteis na população em geral levou ao desenvolvimento de diferentes dispositivos de medição inercial para monitorar as variáveis de atividade e de movimento durante o exercício ou esportes. O objetivo do presente estudo é sistematizar a experiência prática de desenvolvimento de um dispositivo de medição inercial, a fim de quantificar a carga externa em tempo real para os corredores. Este artigo demonstrou a capacidade instalada das instituições de ensino superior da Costa Rica para integrar os sensores existentes disponíveis no mercado internacional em um único dispositivo, com a finalidade de programá-lo e usá-lo para diferentes fins de ciência do esporte. Dois laboratórios científicos uniram forças e integraram uma equipe interdisciplinar composta por fisiologistas do exercício, cientistas do esporte, fisioterapeutas e engenheiros eletromecânicos, que, de forma global, enfrentaram o desafio de criar a IMU. Neste caso, foi desenvolvida uma IMU de grande sucesso, capaz de quantificar variáveis de carga externas controladas a partir de um dispositivo móvel em tempo real. Os resultados mostraram um nível aceitável de concordância e confiabilidade dos dados extraídos da IMU. As informações obtidas desta IMU poderiam ser utilizadas para monitorar e quantificar a carga externa, com o objetivo de implantar ou redirecionar a programação e prescrição de exercícios, bem como com o objetivo de evitar lesões por uso excessivo ou condições de sobrecarga física.

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Human FoxP proteins share a highly conserved DNA-binding domain that dimerizes via three-dimensional domain swapping, although showing varying oligomerization propensities among its members. Here, we present an experimental and computational characterization of all human FoxP proteins to unravel how their amino acid substitutions impact their folding and dimerization mechanism. We solved the crystal structure of the forkhead domain of FoxP4 to then perform a comparison across all members, finding that their sequence changes impact not only the structural heterogeneity of their forkhead domains but also the protein-protein association energy barrier. Lastly, we demonstrate that the accumulation of a monomeric intermediate is an oligomerization-dependent feature rather than a common aspect of monomers and dimers in this protein subfamily.

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Strongyloides stercoralis es un nemátodo que se caracteriza por causar infección intestinal, usualmente asintomática, en pacientes inmunocompetentes. Sin embargo, en aquellos que viven con VIH, y de acuerdo con su estado inmune, puede generar un síndrome de hiperinfección con complicaciones diversas por diseminación a diferentes órganos. Se presenta el caso de un paciente de 30 años con diagnóstico de novo de infección por el virus de la inmunodeficiencia humana, con documentación de enfermedad linfoproliferativa. En los estudios complementarios se documenta la presencia de Strongyloides stercoralis de manera inusual en la médula ósea. A pesar de contar con un recuento de linfocitos T CD4+ mayor a 400 células/ µL y de haberse iniciado el manejo para esta condición con ivermectina, el paciente fallece por un estado séptico asociado al síndrome de hiperinfección, por lo cual se considera que este es un caso inusitado que obliga al clínico a tener en cuenta la presencia del nemátodo en pacientes que viven con VIH.

Summary Strongyloides stercoralis is a nematode that is characterized by causing a usually asymptomatic intestinal infection in immunocompetent individuals. However, in patients living with HIV and depending on their immune status, it can generate a hyperinfection syndrome with various complications due to dissemination to different organs. We present the case of a 30-year-old patient with a de novo diagnosis of human immunodeficiency virus infection and lymphoproliferative disease. Within the laboratory workup, the presence of Strongyloides stercoralis was documented in the bone marrow. Despite having a CD4+ T lymphocyte count greater than 400 cells/microliter and having started treatment for this condition with ivermectin, the patient died due to a septic state associated with hyperinfection syndrome, which is why this is considered an unusual case that alerts the clinician to take into account the presence of the nematode in patients living with HIV.

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Achieving the smart motion of any autonomous or semi-autonomous robot requires an efficient algorithm to determine a feasible collision-free path. In this paper, a novel collision-free path homotopy-based path-planning algorithm applied to planar robotic arms is presented. The algorithm utilizes homotopy continuation methods (HCMs) to solve the non-linear algebraic equations system (NAES) that models the robot's workspace. The method was validated with three case studies with robotic arms in different configurations. For the first case, a robot arm with three links must enter a narrow corridor with two obstacles. For the second case, a six-link robot arm with a gripper is required to take an object inside a narrow corridor with two obstacles. For the third case, a twenty-link arm must take an object inside a maze-like environment. These case studies validated, by simulation, the versatility and capacity of the proposed path-planning algorithm. The results show that the CPU time is dozens of milliseconds with a memory consumption less than 4.5 kB for the first two cases. For the third case, the CPU time is around 2.7 s and the memory consumption around 18 kB. Finally, the method's performance was further validated using the industrial robot arm CRS CataLyst-5 by Thermo Electron.

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Methanogenic archaea have received attention due to their potential use in biotechnological applications such as methane production, so their metabolism and regulation are topics of special interest. When growing in a nutrient-rich medium, these organisms exhibit gluconeogenic metabolism; however, under starvation conditions, they turn to glycolytic metabolism. To date, no regulatory mechanism has been described for this gluconeogenic/glycolytic metabolic switch. Here, we report that adenosine monophosphate (AMP) activates both enzymatic activities of the bifunctional adenosine diphosphate (ADP)-dependent phosphofructokinase/glucokinase from Methanococcus maripaludis (MmPFK/GK). To understand this phenomenon, we performed a comprehensive kinetic characterisation, including determination of the kinetics, substrate inhibition and AMP activation mechanism of this enzyme. We determined that MmPFK/GK has an ordered-sequential mechanism, in which MgADP is the first substrate to bind and AMP is the last product released. The enzyme also displays substrate inhibition by both sugar substrates; we determined that this inhibition occurs through the formation of catalytically nonproductive enzyme complexes caused by sugar binding. For both activities, the AMP activation mechanism occurs primarily through incremental changes in the affinity for the sugar substrate, with this effect being higher in the GK than in the PFK activity. Interestingly, due to the increase in the sugar substrate affinity caused by AMP, an enhancement in the sugar substrate inhibition effect was also observed for both activities, which can be explained by an increase in sugar binding leading to the formation of dead-end complexes. These results shed light on the regulatory mechanisms of methanogenic archaeal sugar metabolism, a phenomenon that has been largely unexplored.

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Endoxylanases belonging to family 10 of the glycoside hydrolases (GH10) are versatile in the use of different substrates. Thus, an understanding of the molecular mechanisms underlying substrate specificities could be very useful in the engineering of GH10 endoxylanases for biotechnological purposes. Herein, we analyzed XynA, an endoxylanase that contains a (ß/α)8-barrel domain and an intrinsically disordered region (IDR) of 29 amino acids at its amino end. Enzyme activity assays revealed that the elimination of the IDR resulted in a mutant enzyme (XynAΔ29) in which two new activities emerged: the ability to release xylose from xylan, and the ability to hydrolyze p-nitrophenyl-ß-d-xylopyranoside (pNPXyl), a substrate that wild-type enzyme cannot hydrolyze. Circular dichroism and tryptophan fluorescence quenching by acrylamide showed changes in secondary structure and increased flexibility of XynAΔ29. Molecular dynamics simulations revealed that the emergence of the pNPXyl-hydrolyzing activity correlated with a dynamic behavior not previously observed in GH10 endoxylanases: a hinge-bending motion of two symmetric regions within the (ß/α)8-barrel domain, whose hinge point is the active cleft. The hinge-bending motion is more intense in XynAΔ29 than in XynA and promotes the formation of a wider active site that allows the accommodation and hydrolysis of pNPXyl. Our results open new avenues for the study of the relationship between IDRs, dynamics and activity of endoxylanases, and other enzymes containing (ß/α)8-barrel domain.

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Background: The lockdown due to COVID-19, has affected the mental health of the population. Recent literature suggests a greater psychological impact on adolescents regardless of their cultural background. Objective: The aim is to analyze the emotional state, life satisfaction and worries about COVID-19 in Chilean and Spanish adolescents. Method: A total of 1078 adolescents (M=15.18; SD=1.25) completed the Depression, Anxiety and Stress Scale, the COVID-19 Worry Scale and the Life Satisfaction Scale. The design was cross-sectional and descriptive. Descriptive analyses, t-tests, and linear regressions were performed. Results: More emotional symptoms, worries and lower life satisfaction were observed in Chile. Girls had more worries and emotional symptoms. An affected psychological state is also observed in Spanish adolescents, especially in Chilean adolescents. Worries about COVID-19 affect depression, anxiety, stress and life satisfaction in both samples. Conclusions: Further research is needed to prevent psychological distress in future pandemics. Developing tailored interventions are encouraged.

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Las queilitis por contacto son procesos patológicos de etiología multifactorial de origen externo que generan lesiones en el bermellón de los labios, en algunos casos se acompaña por una dermatitis contigua. Este tipo de queilitis recibe esta denominación debido al mecanismo de acción de la noxa productora, la cual actúa por contacto en la superficie labial produciendo una reacción antígeno anticuerpo. Los agentes sensibilizantes y desencadenantes del proceso inflamatorio son de origen físico y químico en sus diversas formas. Los físicos son los rayos actínicos y ultravioletas. Los químicos son más numerosos, como los cosméticos, alimentos, pastas y cepillos dentales. La incidencia es alta en el sexo femenino y en el labio inferior por su mayor superficie. El objetivo de este estudio fue realizar una evaluación comparativa de la crema de propóleos en el tratamiento de las queilitis por contacto y de la posible reacción adversa medicamentosa. Se llevó a cabo en pacientes de ambos sexos, a partir de los 15 años con diagnóstico clínico de queilitis por contacto, los que fueron asignados en forma aleatorizada simple en dos grupos. El primer grupo de control, recibió tratamiento tradicional. El segundo grupo experimental recibió la formulación objeto de estudio, la crema de propóleos. Ambas medicaciones redujeron de manera significativa la intensidad de la sintomatología y los signos sin efectos adversos en pacientes con queilitis por contacto. La formulación magistral de crema de propóleos objeto del presente estudio, ha demostrado ser efectiva en el tratamiento de las queilitis por contacto.

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Pressures from anthropogenic activities are causing degradation of estuarine and coastal ecosystems around the world. Trace metals are key pollutants that are released and can partition in a range of environmental compartments, to be ultimately accumulated in exposed biota. The level of pressure varies with locations and the range and intensity of anthropogenic activities. The present study measured residues of trace metals in Mytilus mussel species collected from a range of locations around the world in areas experiencing a gradient of anthropogenic pressures that we classified as low, moderate, or high impact. The data showed no grouping/impact level when sampling sites in all countries were incorporated in the analysis, but there was significant clustering/impact level for most countries. Overall, high-impact areas were characterized by elevated concentrations of zinc, lead, nickel, and arsenic, whereas copper and silver were detected at higher concentrations in medium-impact areas. Finally, whereas most metals were found at lower concentrations in areas classified as low impact, cadmium was typically elevated in these areas. The present study provides a unique snapshot of worldwide levels of coastal metal contamination through the use of Mytilus species, a well-established marine biomonitoring tool. Environ Toxicol Chem 2021;40:3434-3440. © 2021 SETAC.

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Halophilic enzymes need high salt concentrations for activity and stability and are considered a promising source for biotechnological applications. The model study for haloadaptation has been proteins from the Halobacteria class of Archaea, where common structural characteristics have been found. However, the effect of salt on enzyme function and conformational dynamics has been much less explored. Here we report the structural and kinetic characteristics of glucose-6-phosphate dehydrogenase from Haloferax volcanii (HvG6PDH) belonging to the short-chain dehydrogenases/reductases (SDR) superfamily. The enzyme was expressed in Escherichia coli and successfully solubilized and refolded from inclusion bodies. The enzyme is active in the presence of several salts, though the maximum activity is achieved in the presence of KCl, mainly by an increment in the k cat value, that correlates with a diminution of its flexibility according to molecular dynamics simulations. The high K M for glucose-6-phosphate and its promiscuous activity for glucose restrict the use of HvG6PDH as an auxiliary enzyme for the determination of halophilic glucokinase activity. Phylogenetic analysis indicates that SDR-G6PDH enzymes are exclusively present in Halobacteria, with HvG6PDH being the only enzyme characterized. Homology modeling and molecular dynamics simulations of HvG6PDH identified a conserved NLTX2H motif involved in glucose-6-phosphate interaction at high salt concentrations, whose residues could be crucial for substrate specificity. Structural differences in its conformational dynamics, potentially related to the haloadaptation strategy, were also determined.

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Introducción: El crecimiento de los tejidos esqueléticos constituye una respuesta secundaria, compensatoria y mecánicamente obligada a cambiar las matrices funcionales. Cuando por alguna razón las matrices funcionales se ven afectadas en su crecimiento, los tejidos esqueléticos responden también con un grado de afectación dependiendo del momento en que esta se produzca. Entonces la mandíbula como parte del viscerocráneo debe presentar esa relación con el hueso hioides de forma directa. Objetivos: Asociar el comportamiento morfológico del hueso hioides con variables morfológicas de la mandíbula y verificar sí la morfología de los huesos pertenecientes a los esqueletos estudiados está determinada por el conjunto de tejidos blandos que los rodea y marcan el ritmo del proceso de remodelación de crecimiento. Material y Métodos: Se realizó la continuación del estudio osteológico en una muestra ósea de 82 esqueletos con mediciones morfométricas del hueso hioides y la mandíbula. Para evaluar la relación de la morfología del hueso hioides con respecto a la mandíbula, se utilizaron matrices de coeficiente de correlación lineal de Pearson en SPSS versión 22 de Window. Resultados: Se corrobora la relación de la morfología del hueso hioides con el crecimiento del viscerocráneo, debido a la correlación positiva y significativa entre varias variables morfológicas del hioides que se obtuvo, -tanto a nivel de su cuerpo como sus astas o cuernos mayores-, con la mandíbula. Conclusiones: Existe una asociación de la morfología del hueso hioides con respecto a la morfología de la mandíbula(AU)

Introduction: The growth of skeletal tissues constitutes a secondary, compensatory and mechanically obliged response to change the functional matrixes. When the growth of functional matrixes is affected for any reason, the skeletal tissues also respond with a degree of affectation depending on the moment in which it occurs. Then the mandible, as part of the viscerocranium, must present that relationship with the hyoid bone directly. Objective: To associate the morphological behavior of the hyoid bone with the morphological variables of the mandible and verify if the morphology of the bones belonging to the skeletons studied is determined by the set of soft tissues that surround them and set the pace of the growth remodeling process. Material and Methods: The continuation of the osteological study was carried out in a bone sample of 82 skulls by performing morphometric measurements of the hyoid bone and the mandible. Pearson's linear correlation coefficient matrices in SPSS Version 22 were used to evaluate the relationship between the morphology of the hyoid bone and the bones of the mandible. Results: The relationship between the morphology of the hyoid bone and the growth of the viscerocranium is corroborated by the positive and significant correlation between several morphological variables of the hyoid bone obtained - both at the level of its body and its greater horns -, and the mandible. Conclusions: These findings corroborate the association between the morphology of the hyoid bone and the growth of the mandible(AU)

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RESUMEN

Introducción: El movimiento corporal, obedece y produce actividad del músculo esquelético para lo cual debe existir un equilibrio muscular estático, a partir del cual se genere el desplazamiento de los elementos anatómicos, involucrados en él, ya sea como respuesta a la volición o a la percepción inconsciente al estímulo que lo demande. Objetivo: Asociar el comportamiento morfológico del hioides con ciertas variables morfológicas del viscerocráneo de esqueletos (excepto la mandíbula). Material y Métodos: Se realizó estudio osteológico en una muestra ósea de 82 esqueletos mediante mediciones morfométricas del hueso hioides y huesos del viscerocráneo. Se utilizaron matrices de coeficiente de correlación lineal de Pearson en SPSS 22 para evaluar la relación de la morfología del hioides con respecto a la morfología de los huesos de la cara. Variables morfológicas del viscerocráneo como ancho bicigomático (abc), ancho transversal externo del paladar óseo (pote), ancho sagital externo del paladar óseo (pose) y la altura del tercio medio de la cara (tmed). Resultados: Se obtuvo una gran correlación positiva y significativa de distintas variables morfológicas del hioides, -tanto de su cuerpo como de sus astas o cuernos mayores- con las variables morfológicas del viscerocráneo. Conclusiones: Se corrobora la asociación de la morfología del hueso hioides con el crecimiento de los huesos del viscerocráneo(AU)

Introduction: Body movement obeys and produces activity in the skeletal muscle for which there must be a static muscle equilibrium that produces the movement of the anatomic elements involved in it, either as a result of volition or as the unconscious perception of a stimulus. Objective: To associate the morphological behavior of the hyoid bone with some morphological variables of the viscerocranium of skeletons (except the jaw). Material and Methods: An osteological study was carried out in a bone sample of 82 skulls by performing morphometric measurements of the hyoid bone and the bones of the viscerocranium. Pearson's correlation coefficient and SPSS Version 22 were used to evaluate the relationship between the morphology of the hyoid bone and the facial bones. Morphological variables of the viscerocranium include: bizygomatic width (BW), external transverse width of the hard palate (ETWHP), external sagittal width of the hard palate (ESWHP), and the height of the middle third of the face (MTF). Results: A very strong positive correlation between different morphological variables of the hyoid bone, -both at the level of its antlers or greater horns- and the morphological variables of the viscerocranium was obtained. Conclusions: These findings corroborate the association between the hyoid bone and the growth of facial bones(AU)

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