Salivary gland developmental mechanics.

The salivary gland undergoes branching morphogenesis to elaborate into a tree-like structure with numerous saliva-secreting acinar units, all joined by a hierarchical ductal system. The expansive epithelial surface generated by branching morphogenesis serves as the structural basis for the efficient production and delivery of saliva. Here, we elucidate the process of salivary gland morphogenesis, emphasizing the role of mechanics. Structurally, the developing salivary gland is characterized by a stratified epithelium tightly encased by the basement membrane, which is in turn surrounded by a mesenchyme consisting of a dense network of interstitial matrix and mesenchymal cells. Diverse cell types and extracellular matrices bestow this developing organ with organized, yet spatially varied mechanical properties. For instance, the surface epithelial sheet of the bud is highly fluidic due to its high cell motility and weak cell-cell adhesion, rendering it highly pliable. In contrast, the inner core of the bud is more rigid, characterized by reduced cell motility and strong cell-cell adhesion, which likely provide structural support for the tissue. The interactions between the surface epithelial sheet and the inner core give rise to budding morphogenesis. Furthermore, the basement membrane and the mesenchyme offer mechanical constraints that could play a pivotal role in determining the higher-order architecture of a fully mature salivary gland.

Mitotic spindle positioning protein (MISP) preferentially binds to aged F-actin.

Actin bundling proteins crosslink filaments into polarized structures that shape and support membrane protrusions including filopodia, microvilli, and stereocilia. In the case of epithelial microvilli, mitotic spindle positioning protein (MISP) is an actin bundler that localizes specifically to the basal rootlets, where the pointed ends of core bundle filaments converge. Previous studies established that MISP is prevented from binding more distal segments of the core bundle by competition with other actin-binding proteins. Yet whether MISP holds a preference for binding directly to rootlet actin remains an open question. By immunostaining native intestinal tissue sections, we found that microvillar rootlets are decorated with the severing protein, cofilin, suggesting high levels of ADP-actin in these structures. Using total internal reflection fluorescence microscopy assays, we also found that purified MISP exhibits a binding preference for ADP- versus ADP-Pi-actin-containing filaments. Consistent with this, assays with actively growing actin filaments revealed that MISP binds at or near their pointed ends. Moreover, although substrate attached MISP assembles filament bundles in parallel and antiparallel configurations, in solution MISP assembles parallel bundles consisting of multiple filaments exhibiting uniform polarity. These discoveries highlight nucleotide state sensing as a mechanism for sorting actin bundlers along filaments and driving their accumulation near filament ends. Such localized binding might drive parallel bundle formation and/or locally modulate bundle mechanical properties in microvilli and related protrusions.

[Family planning in men and women with multiple sclerosis. Analysis of the Andalusian Registry (2018-2022)]. / Planificación familiar en hombres y mujeres con esclerosis múltiple. Análisis del Registro Andaluz (2018-2022).

INTRODUCTION: The Andalusian Registry of Pregnancies in patients with multiple sclerosis is the largest Spanish registry on multiple sclerosis (MS) and family planning. For the first time, it includes information on the fertility of men with MS. The influence of the use of a disease-modifying treatment (DMT) on the health of the foetus/newborn and the impact of breastfeeding on MS are also analysed. SUBJECTS AND METHODS: This is a multicentre, prospective and observational study. Recruitment of patients took place between December 2018 and December 2020. Women were followed up for one year after delivery. Altogether 100 women and 16 men were included, with a total of 103 newborn infants. RESULTS: The annualised relapse rate of the women with MS decreased significantly during pregnancy (from 0.23 to 0.065). A total of 11.2% of patients resorted to assisted reproductive techniques in order to conceive a child. No association was found between the use of a DMT at conception and/or pregnancy and the risk of miscarriage, prematurity or low birth weight. Over half the women with MS (54.2%) chose to breastfeed (26.7% of them while on a DMT). CONCLUSIONS: MS does not affect the fertility of men. Neither does the use of a DMT at the time of conception affect their fertility or their children's health. Assisted reproductive techniques did not have a negative impact on the course of MS. Breastfeeding is a common practice among women with MS and there is no evidence of positive or negative effects on disease progression.

TITLE: Planificación familiar en hombres y mujeres con esclerosis múltiple. Análisis del Registro Andaluz (2018-2022).Introducción. El Registro Andaluz de Embarazos en pacientes con esclerosis múltiple (EM) es el mayor registro español sobre EM y planificación familiar. Por primera vez se incluye información sobre la fertilidad de hombres con EM. También se analizan la influencia del uso de un tratamiento modificador de la enfermedad (TME) en la salud del feto o recién nacido y el impacto de la lactancia materna en la EM. Sujetos y métodos. Es un estudio observacional, prospectivo y multicéntrico. El reclutamiento de pacientes se hizo entre diciembre de 2018 y diciembre de 2020. El seguimiento de las mujeres tras el parto fue de un año. Se incluyó a 100 mujeres y 16 hombres, con un total de 103 recién nacidos. Resultados. La tasa anualizada de brotes de las mujeres con EM descendió durante el embarazo de forma significativa (de 0,23 a 0,065). Un 11,2% de los pacientes recurrieron a técnicas de reproducción asistida para conseguir la gestación. No se encontró relación entre el uso de un TME en la concepción y/o embarazo y el riesgo de aborto, prematuridad o bajo peso al nacer. El 54,2% de las mujeres con EM optaron por dar lactancia (el 26,7% de ellas usando un TME). Conclusiones. La EM no afecta a la fertilidad de los hombres. Tampoco influye en ésta, ni en la salud de sus hijos, el uso de un TME en el momento de la concepción. Las técnicas de reproducción asistida no impactaron negativamente en la evolución de la EM. La lactancia se impone como una práctica habitual entre las mujeres con EM y no se evidencian efectos positivos o negativos sobre la evolución de la enfermedad.

Mitotic spindle positioning protein (MISP) is an actin bundler that senses ADP-actin and binds near the pointed ends of filaments.

Actin bundling proteins crosslink filaments into polarized structures that shape and support membrane protrusions including filopodia, microvilli, and stereocilia. In the case of epithelial microvilli, mitotic spindle positioning protein (MISP) is an actin bundler that localizes specifically to the basal rootlets, where the pointed ends of core bundle filaments converge. Previous studies established that MISP is prevented from binding more distal segments of the core bundle by competition with other actin binding proteins. Yet whether MISP holds a preference for binding directly to rootlet actin remains an open question. Using in vitro TIRF microscopy assays, we found that MISP exhibits a clear binding preference for filaments enriched in ADP-actin monomers. Consistent with this, assays with actively growing actin filaments revealed that MISP binds at or near their pointed ends. Moreover, although substrate attached MISP assembles filament bundles in parallel and antiparallel configurations, in solution MISP assembles parallel bundles consisting of multiple filaments exhibiting uniform polarity. These discoveries highlight nucleotide state sensing as a mechanism for sorting actin bundlers along filaments and driving their accumulation near filament ends. Such localized binding might drive parallel bundle formation and/or locally modulate bundle mechanical properties in microvilli and related protrusions.

Influence of shell thickness on the thermal stability and melting-like behavior of Al@Fe core-shell nanoparticles from atomistic simulations: a structural and dynamic description.

Core-shell nanoparticles (CSNPs) are a class of functional materials that have received important attention nowadays due to their adjustable properties by a controlled tuning of the core or shell. Understanding the thermal response and structural properties of these CSNPs is relevant to carrying out an analysis regarding their synthesis and application at the nanoscale. The present work is aimed to investigate the shell thickness effect on thermal stability and melting behavior of Al@Fe CSNPs by using molecular dynamics simulations. The results are discussed considering the influence of the Fe shell on the Al nanoparticle and analyzing the effect of different shell thicknesses in Al@Fe CSNPs. In general, calorific curves show a smooth energy decline for temperatures greater than room temperature for different shell thicknesses and sizes, corresponding to the inward and outward atomic movement of Al and Fe atoms, respectively, that produce a mixed Al-Fe nanoalloy. Here, the thermal stability of the Al@Fe nanoparticle is gradually lost passing to a liquid-Al@solid-Fe configuration and reaching a mixed Al-Fe state by an exothermic mechanism. Combining quantities of the atomic diffusion and structural identification, a stepped structural transition of the system is subsequently observed, where the melting-like point was estimated. Furthermore, it is observed that the Al@Fe CSNPs with greater stability are obtained with a thick shell and a large size. The ability to control shell thickness and vary the size opens up attractive opportunities to synthesize a broad range of new materials with tunable catalytic properties.

Building the brush border, one microvillus at a time.

Microvilli are actin bundle-supported surface protrusions assembled by diverse cell types to mediate biochemical and physical interactions with the external environment. Found on the surface of some of the earliest animal cells, primordial microvilli likely contributed to bacterial entrapment and feeding. Although millions of years of evolution have repurposed these protrusions to fulfill diverse roles such as detection of mechanical or visual stimuli in inner ear hair cells or retinal pigmented epithelial cells, respectively, solute uptake remains a key essential function linked to these structures. In this mini review, we offer a brief overview of the composition and structure of epithelial microvilli, highlight recent discoveries on the growth of these protrusions early in differentiation, and point to fundamental questions surrounding microvilli biogenesis that remain open for future studies.

Giant valley-Zeeman coupling in the surface layer of an intercalated transition metal dichalcogenide.

Spin-valley locking is ubiquitous among transition metal dichalcogenides with local or global inversion asymmetry, in turn stabilizing properties such as Ising superconductivity, and opening routes towards 'valleytronics'. The underlying valley-spin splitting is set by spin-orbit coupling but can be tuned via the application of external magnetic fields or through proximity coupling. However, only modest changes have been realized to date. Here, we investigate the electronic structure of the V-intercalated transition metal dichalcogenide V1/3NbS2 using microscopic-area spatially resolved and angle-resolved photoemission spectroscopy. Our measurements and corresponding density functional theory calculations reveal that the bulk magnetic order induces a giant valley-selective Ising coupling exceeding 50 meV in the surface NbS2 layer, equivalent to application of a ~250 T magnetic field. This energy scale is of comparable magnitude to the intrinsic spin-orbit splittings, and indicates how coupling of local magnetic moments to itinerant states of a transition metal dichalcogenide monolayer provides a powerful route to controlling their valley-spin splittings.

Searching for a prognostic index in lupus nephritis.

BACKGROUND: Currently we do not have an ideal biomarker in lupus nephritis (LN) that should help us to identify those patients with SLE at risk of developing LN or to determine those patients at risk of renal progression. We aimed to evaluate the development of a prognostic index for LN, through the evaluation of clinical, analytical and histological factors used in a cohort of lupus. We have proposed to determine which factors, 6 months after the diagnosis of LN, could help us to define which patients will have a worse evolution of the disease and may be, more aggressive treatment and closer follow-up. METHODS: A retrospective study to identify prognostic factors was carried out. We have included patients over 18 years of age with a clinical diagnosis of systemic lupus erythematosus (SLE) and kidney involvement confirmed by biopsy, who are followed up in our centre during the last 20 years. A multi-step statistical approach will be used in order to obtain a limited set of parameters, optimally selected and weighted, that show a satisfactory ability to discriminate between patients with different levels of prognosis. RESULTS: We analysed 92 patients with LN, although only 73 have been able to be classified according to whether or not they have presented poor renal evolution. The age of onset (44 vs. 32; p = 0.024), the value of serum creatinine (1.41 vs. 1.04; p = 0.041), greater frequency of thrombocytopenia (30 vs. 7%; p = 0.038), higher score in the renal chronicity index (2.47 vs. 1.04; p = 0.015), proliferative histological type (100%) and higher frequency of interstitial fibrosis (67 vs. 32%; p = 0.017) and tubular atrophy (67 vs. 32%; p = 0.018) was observed between two groups. The multivariate analysis allowed us to select the best predictive model for poor outcome at 6 months based on different adjustment and discrimination parameters. CONCLUSION: We have developed a prognostic index of poor renal evolution in patients with LN that combines demographic, clinical, analytical and histopathological factors, easy to use in routine clinical practice and that could be an effective tool in the early detection and management.

Mitotic Spindle Positioning (MISP) is an actin bundler that selectively stabilizes the rootlets of epithelial microvilli.

Microvilli are conserved actin-based surface protrusions that have been repurposed throughout evolution to fulfill diverse cell functions. In the case of transporting epithelia, microvilli are supported by a core of actin filaments bundled in parallel by villin, fimbrin, and espin. Remarkably, microvilli biogenesis persists in mice lacking all three of these factors, suggesting the existence of unknown bundlers. We identified Mitotic Spindle Positioning (MISP) as an actin-binding factor that localizes specifically to the rootlet end of the microvillus. MISP promotes rootlet elongation in cells, and purified MISP exhibits potent filament bundling activity in vitro. MISP-bundled filaments also recruit fimbrin, which further elongates and stabilizes bundles. MISP confinement to the rootlet is enforced by ezrin, which prevents decoration of the membrane-wrapped distal end of the core bundle. These discoveries reveal how epithelial cells optimize apical membrane surface area and offer insight on the remarkable robustness of microvilli biogenesis.

Genetic regulation of the ompX porin of Salmonella Typhimurium in response to hydrogen peroxide stress.

BACKGROUND: Salmonella Typhimurium is a Gram-negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella-containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin-encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post-transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. RESULTS: In this work we sought to evaluate the transcriptional and post-transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S. Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild-type strain, suggesting that ompX mRNA is also regulated at a post-transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2-induced stress in Salmonella during the exponential growth phase in Lennox broth. CONCLUSIONS: Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium.

Genetic regulation of the ompX porin of Salmonella Typhimurium in response to hydrogen peroxide stress

BACKGROUND: Salmonella Typhimurium is a Gram negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. RESULTS: In this work we sought to evaluate the transcriptional and post transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S . Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild type strain, suggesting that ompX mRNA is also regulated at a post transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2 induced stress in Salmonella during the exponential growth phase in Lennox broth. CONCLUSIONS: Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium.

SARS-CoV-2 induces mitochondrial dysfunction and cell death by oxidative stress/inflammation in leukocytes of COVID-19 patients.

The inflammation and activation of the immune system induced by SARS-CoV-2 are mediated by a pro-oxidant microenvironment that can induce cytotoxic effects that enhance tissue damage, favoring organic deterioration. We investigated whether the induction of oxidative stress and inflammation by COVID-19 infection could inhibit mitochondrial function and cause cellular damage in leukocytes. We evaluated levels of oxidative/inflammation markers and their correlation with mitochondrial function and leukocyte cell death in COVID-19 patients at two moments: viremia and severe sepsis with multi-organ failure. COVID-19 induces increased oxidative stress and inflammation markers that activate cellular damage processes. In the viremia stage, an increase in peroxide, nitric oxide, carbonylated proteins, and IL-6 was observed, which was correlated with a marked inhibition of mitochondrial function, decreased cell viability, early apoptosis, necrosis, and leukocytes-reactivity. The severe sepsis stage with multi-organ failure also showed a further increase in levels of peroxide, carbonylated proteins, and IL-6, with a slight decrease in nitric oxide. This oxidative process and inflammation were correlated with less inhibition of mitochondrial function, decreased cell viability and an increase in late apoptosis, and morphology changes evidencing damage in the leukocytes. SARS-CoV-2 induced damage promotes levels of oxidative stress and inflammation markers and mitochondrial dysfunction that potentiate morphological changes and cell death in leukocytes. These processes explain the rapid changes in the immune system, and that present an initial over-activation and early massive death due to SARS-CoV-2 infection, promoting endothelial-alveolar damage that would cause multi-organ failure, sustained by oxidative stress and inflammation.

Brachial-ankle pulse wave velocity with a custom device.

BACKGROUND AND OBJECTIVES: The brachial-ankle pulse wave velocity (baPWV) is one of the most widely used arterial stiffness variables for assessing vascular risk. The abiPWV is a device that calculates various PWVs and the blood pressure ankle-brachial index (ABI). The device can also determine baPWV. The aim of this study was to calculate the baPWV with abiPWV, validate it with a reference device (VaSera) and study its clinical usefulness. PATIENTS AND METHODS: We studied 113 patients (mean age, 53 ±â€¯12 years), 59 (52%) of whom were women, and 10 (8.8%) of whom had a previous cardiovascular event. The participants were classified according to cardiovascular risk factors (CRFs) into group I (none), group II (1 or 2 CRFs) and group III (3 or more CRFs). The patients with a previous cardiovascular event were included in group III. All participants had their baPWV measured with abiPWV and VaSera. RESULTS: The baPWV correlation between the 2 devices was r = 0.93 (p < .001), and the percentage error calculated with the Bland-Altman analysis was 4.5%. The baPWV measured with abiPWV (in m/s) was as follows: group I, 10.5 ±â€¯1.6; group II, 13.8 ±â€¯2.9 (p < .001 when compared with group I); and group III, 14.1 ±â€¯2.7 (p < .001 when compared with group I). There were no differences between groups II and III. The results with VaSera were comparable to those of abiPWV. CONCLUSIONS: Measuring baPWV with the abiPWV is safe and has a similar clinical utility to that of VaSera. Incorporating this function into the options of abiPWV makes it a complete device for assessing arterial stiffness.

Brachial-ankle pulse wave velocity with a custom device. / Velocidad de onda de pulso brazo-tobillo con un dispositivo propio.

BACKGROUND AND OBJECTIVES: The brachial-ankle pulse wave velocity (baPWV) is one of the most widely used arterial stiffness variables for assessing vascular risk. The abiPWV is a device that calculates various PWVs and the blood pressure ankle-brachial index (ABI). The device can also determine baPWV. The aim of this study was to calculate the baPWV with abiPWV, validate it with a reference device (VaSera) and study its clinical usefulness. PATIENTS AND METHODS: We studied 113 patients (mean age, 53±12years), 59 (52%) of whom were women, and 10 (8.8%) of whom had a previous cardiovascular event. The participants were classified according to cardiovascular risk factors (CRFs) into groupI (none), groupII (1 or 2 CRFs) and groupIII (3 or more CRFs). The patients with a previous cardiovascular event were included in groupIII. All participants had their baPWV measured with abiPWV and VaSera. RESULTS: The baPWV correlation between the 2 devices was r=0.93 (P<.001), and the percentage error calculated with the Bland-Altman analysis was 4.5%. The baPWV measured with abiPWV (in m/s) was as follows: groupI, 10.5±1.6; groupII, 13.8±2.9 (P<.001 when compared with groupI); and groupIII, 14.1±2.7 (P<.001 when compared with groupI). There were no differences between groupsII and III. The results with VaSera were comparable to those of abiPWV. CONCLUSIONS: Measuring baPWV with the abiPWV is safe and has a similar clinical utility to that of VaSera. Incorporating this function into the options of abiPWV makes it a complete device for assessing arterial stiffness.

Review: Ruminal microbiome and microbial metabolome: effects of diet and ruminant host.

The rumen contains a great diversity of prokaryotic and eukaryotic microorganisms that allow the ruminant to utilize ligno-cellulose material and to convert non-protein nitrogen into microbial protein to obtain energy and amino acids. However, rumen fermentation also has potential deleterious consequences associated with the emissions of greenhouse gases, excessive nitrogen excreted in manure and may also adversely influence the nutritional value of ruminant products. While several strategies for optimizing the energy and nitrogen use by ruminants have been suggested, a better understanding of the key microorganisms involved and their activities is essential to manipulate rumen processes successfully. Diet is the most obvious factor influencing the rumen microbiome and fermentation. Among dietary interventions, the ban of antimicrobial growth promoters in animal production systems has led to an increasing interest in the use of plant extracts to manipulate the rumen. Plant extracts (e.g. saponins, polyphenol compounds, essential oils) have shown potential to decrease methane emissions and improve the efficiency of nitrogen utilization; however, there are limitations such as inconsistency, transient and adverse effects for their use as feed additives for ruminants. It has been proved that the host animal may also influence the rumen microbial population both as a heritable trait and through the effect of early-life nutrition on microbial population structure and function in adult ruminants. Recent developments have allowed phylogenetic information to be upscaled to metabolic information; however, research effort on cultivation of microorganisms for an in-depth study and characterization is needed. The introduction and integration of metagenomic, transcriptomic, proteomic and metabolomic techniques is offering the greatest potential of reaching a truly systems-level understanding of the rumen; studies have been focused on the prokaryotic population and a broader approach needs to be considered.

Not all saponins have a greater antiprotozoal activity than their related sapogenins.

The antiprotozoal effect of saponins varies according to both the structure of the sapogenin and the composition and linkage of the sugar moieties to the sapogenin. The effect of saponins on protozoa has been considered to be transient as it was thought that when saponins were deglycosilated to sapogenins in the rumen they became inactive; however, no studies have yet evaluated the antiprotozoal effect of sapogenins compared to their related saponins. The aims of this study were to evaluate the antiprotozoal effect of eighteen commercially available triterpenoid and steroid saponins and sapogenins in vitro, to investigate the effect of variations in the sugar moiety of related saponins and to compare different sapogenins bearing identical sugar moieties. Our results show that antiprotozoal activity is not an inherent feature of all saponins and that small variations in the structure of a compound can have a significant influence on their biological activity. Some sapogenins (20(S)-protopanaxatriol, asiatic acid and madecassic acid) inhibited protozoa activity to a greater extent than their corresponding saponins (Re and Rh1 and asiaticoside and madecassoside), thus the original hypothesis that the transient nature of the antiprotozoal action of saponins is due to the deglycosilation of saponins needs to be revisited.

Eficacia de la viscosuplementación con ácido hialurónico de alto y de mediano peso molecular en pacientes con gonartrosis sintomática grados II-III / Efficacy of viscosupplementation with high and medium molecular weight hyaluronic acid in patients with symptomatic gonarthrosis grades II-III

Resumen: Introducción: La osteoartrosis es actualmente la quinta causa de discapacidad en el adulto. Su prevalencia aumenta a partir de los 40 años. La viscosuplementación es un tratamiento para las etapas iniciales de la osteoartrosis de rodilla. Objetivo: Comparar la eficacia y la calidad de vida en pacientes con gonartrosis sintomática tratados con ácido hialurónico de alto y mediano peso molecular. Material y métodos: Estudio analítico, retrospectivo, transversal, observacional de expedientes clínicos de pacientes con diagnóstico de gonartrosis grado II y grado III, de Octubre de 2017 a Junio de 2018, tratados con viscosuplementación con ácido hialurónico de alto o de mediano peso molecular; se analizó la calidad de vida y la escala de WOMAC de manera previa a la primera aplicación y con seguimiento a los dos, cuatro y seis meses. Resultados: 194 pacientes, con edades entre 30 y 87 años (promedio 61.85; DE = 11.3); 134 mujeres (69.1%) y 60 hombres (30.9%). En ambos grupos la evolución fue hacia la mejoría, con disminución en el puntaje WOMAC, sin diferencia significativa entre grupos. El puntaje de WOMAC tuvo un aumento mínimo pasados seis meses de la aplicación en ambos grupos, lo que se interpreta como disminución del efecto terapéutico. Dos pacientes tuvieron reacciones adversas mínimas localizadas, las cuales se resolvieron con medidas generales. Conclusión: El ácido hialurónico en ambas presentaciones, de alto y de bajo peso molecular, es efectivo en el tratamiento de la gonartrosis sintomática sin diferencia con el peso molecular.

Abstract: Introduction: OA is currently the fifth leading cause of adult disability, its prevalence increases from age 40. Viscosupplementation is a treatment for the early stages of knee OA. Objective: To compare efficacy and quality of life in patients with symptomatic gonartrosis, treated with high and low molecular weight hyaluronic acid. Material and methods: Analytical, retrospective, cross-sectional, observational study of clinical records of patients diagnosed with grade II and grade III gonarthrosis, October 2017 to June 2018, treated with viscosupplementation with high molecular weight hyaluronic acid or low molecular weight; WOMAC quality of life and scale were analyzed prior to the first application and tracked at two, four and six months. Results: 194 patients, aged between 30 to 87 years (promedio 61.85; SD = 11.3); 134 women (69.1%), 60 men (30.9%). In both groups the evolution was towards improvement, with a decrease in the WOMAC score, with no significant difference between groups. The WOMAC score had a minimum increase after 6 months of application in both groups, which is interpreted as decreasing the therapeutic effect. Two patients had localized minimal adverse reactions which were resolved with general measures. Conclusion: Hyaluronic acid in both presentations, high and low molecular weight, are effective in the treatment of symptomatic goonarthrosis without difference to molecular weight.

Synthesis of Ruthenium-Doped TiO2 Nanotube Arrays for the Photocatalytic Degradation of Terasil Blue Dye.

The oxidation of terasil blue dye (TB) has been achieved by photocatalysis under UV light using well organized nanotubes of Ti/TiO2 doped with ruthenium (Ru/Ti/TiO2). Ru/Ti/TiO2 were fabricated by Ti anodization followed by impregnation with 0.04, 0.08 and 0.16 wt% of RuCl3 · xH2O or KRuO4 as precursor salts. Ti foil anodization was carried out in non-aqueous solutions and in aqueous solutions at pH 7 and pH 12.6. Scanning electron microscopy analyses revealed a morphology of well-defined, organized nanotubes of Ti/TiO2 and Ru/Ti/TiO2. The ruthenium was evenly distributed over Ti/TiO2 surface. Cluster formation was also observed for 0.16 wt% Ru loading. The X-ray diffraction spectra showed anatase and rutile phase in pure Ti/TiO2 and Ru/Ti/TiO2 nanotubes. Therefore, ruthenium doping did not modify the crystalline phase of Ti/TiO2. Raman spectra did not reveal the rutile phase of TiO2 in the composites which is attributed to the laser characteristics used. The optical band gap energies of the Ti/TiO2 and Ru/Ti/TiO2 nanotube arrays showed that ruthenium-doping on Ti/TiO2 had slight effect on the band-gap energy. A decrease in the band gap energy of pure Ti/TiO2 (Eg 2.88 eV) was observed by Ru loading of 0.04 wt% in the Ti/TiO2 nanotube arrays (Eg 2.60 eV). The kinetic rate constant of the photocatalytic oxidation of TB, using 0.08 wt% Ru load, was 1.56 and 1.39 times of that on Ti/TiO2 composite (0.01 min-1) synthetized at pH 12.6 impregnated in RuCl3 (0.0156 min-1) and KRuO4 (0.0139 min-1) solutions, respectively. Nevertheless, the highest rate constant value of TB degradation (87.8%) was 0.0172 min-1 using 0.16 wt% Ru loading on Ti/TiO2 composite synthetized at pH 7 impregnated in RuCl3; this represents 1.15 times of that on Ti/TiO2 composite (0.0150 min-1; 81.4% color removal) synthetized under the same conditions.