Determination of mandibular distraction osteogenesis most suitable parameters. An experimental study.

BACKGROUND: Distraction osteogenesis is a process of induced bone generation. Various protocols have been described for the management of the latency period, distraction speed and consolidation period, with greater or lesser success. OBJECTIVE: To better understand the process of mandibular distraction and establish the determining factors and their optimal times. MATERIAL AND METHODS: Twenty-seven dogs were studied, which had 54 distractors placed and that underwent unidirectional, bilateral mandibular distraction osteogenesis. The distraction processes were applied using six variants, two for each factor: latency period, distraction period and distraction speed. The changes were examined by means of bone biopsies and X-rays of the area at 0, 7, 14, 21, 45 and 55 days of the process. RESULTS: The most efficient osteogenic distraction parameters were a latency period of five days, a consolidation period of six weeks, distraction speed of 1 mm/day for distances of less than 20 mm, and 3 mm/day for longer distances. CONCLUSIONS: The sequential histological study allowed to observe the appearance of cellular elements (osteocytes, osteoclasts, osteoid matrix, trabeculate, etc.) and their participation in granulation tissue, newly-formed bone and compact mature bone.

ANTECEDENTES: Respecto a la distracción osteogénica (generación ósea inducida), con mayor o menor éxito han sido descritos diversos protocolos para el manejo del período de latencia, velocidad de distracción y período de consolidación. ­. OBJETIVO: Entender mejor el proceso de la distracción mandibular y establecer los factores determinantes y sus tiempos óptimos. MATERIAL Y MÉTODOS: Se estudiaron 27 perros sometidos a distracción osteogénica unidireccional, bilateral de la mandíbula. Los procesos de distracción se aplicaron con seis variantes, dos por cada factor (período de latencia, período de distracción y velocidad de distracción). Se estudiaron los cambios mediante biopsias del hueso y radiografías de la zona a los 0, 7, 14, 21, 45 y 55 días del proceso. RESULTADOS: Los parámetros de distracción osteogénica más eficientes fueron período de latencia de cinco días, período de consolidación de seis semanas, 1 mm diario de velocidad de distracción para distancias menores a 20 mm y 3 mm diarios para distancias mayores. CONCLUSIONES: El estudio histológico secuencial permitió observar la aparición de los elementos celulares (osteocitos, osteoclastos, matriz osteoide, trabeculado, etcétera) y su participación en el tejido de granulación, el hueso neoformado y el hueso maduro compacto.

Histomorphologic, Biomechanical, and Functional Analysis in Mandibular Osteogenesis Induced by External Distraction.

The induced bone generation procedure (osteogenic distraction [OD]) is frequently used in cases of jaw deformities in patients with, hemifacial microsomia, mandibular hypoplasia, and so on. This study was undertaken to provide criteria to perform this procedure. The authors evaluated the effects of various parameters using OD to determine the optimal variables. Sixty distractors were placed in 30 canine subjects who then underwent OD after appropriate osteotomy. The procedures were performed during varying latency periods, distraction periods, distraction rate distance, and the consolidation period. Bone biopsies and radiographic studies were performed at 0, 7, 14, 21, 45, and 55 days after the distraction process. The observed changes and the most efficient mandibular OD parameters are reported.

Beyond genetics: Deciphering the impact of missense variants in CAD deficiency.

CAD is a large, 2225 amino acid multienzymatic protein required for de novo pyrimidine biosynthesis. Pathological CAD variants cause a developmental and epileptic encephalopathy which is highly responsive to uridine supplements. CAD deficiency is difficult to diagnose because symptoms are nonspecific, there is no biomarker, and the protein has over 1000 known variants. To improve diagnosis, we assessed the pathogenicity of 20 unreported missense CAD variants using a growth complementation assay that identified 11 pathogenic variants in seven affected individuals; they would benefit from uridine treatment. We also tested nine variants previously reported as pathogenic and confirmed the damaging effect of seven. However, we reclassified two variants as likely benign based on our assay, which is consistent with their long-term follow-up with uridine. We found that several computational methods are unreliable predictors of pathogenic CAD variants, so we extended the functional assay results by studying the impact of pathogenic variants at the protein level. We focused on CAD's dihydroorotase (DHO) domain because it accumulates the largest density of damaging missense changes. The atomic-resolution structures of eight DHO pathogenic variants, combined with functional and molecular dynamics analyses, provided a comprehensive structural and functional understanding of the activity, stability, and oligomerization of CAD's DHO domain. Combining our functional and protein structural analysis can help refine clinical diagnostic workflow for CAD variants in the genomics era.

C-2 Thiophenyl Tryptophan Trimers Inhibit Cellular Entry of SARS-CoV-2 through Interaction with the Viral Spike (S) Protein.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, by infecting cells via the interaction of its spike protein (S) with the primary cell receptor angiotensin-converting enzyme (ACE2). To search for inhibitors of this key step in viral infection, we screened an in-house library of multivalent tryptophan derivatives. Using VSV-S pseudoparticles, we identified compound 2 as a potent entry inhibitor lacking cellular toxicity. Chemical optimization of 2 rendered compounds 63 and 65, which also potently inhibited genuine SARS-CoV-2 cell entry. Thermofluor and microscale thermophoresis studies revealed their binding to S and to its isolated receptor binding domain (RBD), interfering with the interaction with ACE2. High-resolution cryoelectron microscopy structure of S, free or bound to 2, shed light on cell entry inhibition mechanisms by these compounds. Overall, this work identifies and characterizes a new class of SARS-CoV-2 entry inhibitors with clear potential for preventing and/or fighting COVID-19.

A Tailored Strategy to Crosslink the Aspartate Transcarbamoylase Domain of the Multienzymatic Protein CAD.

CAD is a 1.5 MDa hexameric protein with four enzymatic domains responsible for initiating de novo biosynthesis of pyrimidines nucleotides: glutaminase, carbamoyl phosphate synthetase, aspartate transcarbamoylase (ATC), and dihydroorotase. Despite its central metabolic role and implication in cancer and other diseases, our understanding of CAD is poor, and structural characterization has been frustrated by its large size and sensitivity to proteolytic cleavage. Recently, we succeeded in isolating intact CAD-like particles from the fungus Chaetomium thermophilum with high yield and purity, but their study by cryo-electron microscopy is hampered by the dissociation of the complex during sample grid preparation. Here we devised a specific crosslinking strategy to enhance the stability of this mega-enzyme. Based on the structure of the isolated C. thermophilum ATC domain, we inserted by site-directed mutagenesis two cysteines at specific locations that favored the formation of disulfide bridges and covalent oligomers. We further proved that this covalent linkage increases the stability of the ATC domain without damaging the structure or enzymatic activity. Thus, we propose that this cysteine crosslinking is a suitable strategy to strengthen the contacts between subunits in the CAD particle and facilitate its structural characterization.

Replication of Human Norovirus in Mice after Antibiotic-Mediated Intestinal Bacteria Depletion.

Human noroviruses (HuNoVs) are the main cause of acute gastroenteritis causing more than 50,000 deaths per year. Recent evidence shows that the gut microbiota plays a key role in enteric virus infectivity. In this context, we tested whether microbiota depletion or microbiota replacement with that of human individuals susceptible to HuNoVs infection could favor viral replication in mice. Four groups of mice (n = 5) were used, including a control group and three groups that were treated with antibiotics to eliminate the autochthonous intestinal microbiota. Two of the antibiotic-treated groups received fecal microbiota transplantation from a pool of feces from infants (age 1-3 months) or an auto-transplantation with mouse feces that obtained prior antibiotic treatment. The inoculation of the different mouse groups with a HuNoVs strain (GII.4 Sydney [P16] genotype) showed that the virus replicated more efficiently in animals only treated with antibiotics but not subject to microbiota transplantation. Viral replication in animals receiving fecal microbiota from newborn infants was intermediate, whereas virus excretion in feces from auto-transplanted mice was as low as in the control mice. The analysis of the fecal microbiota by 16S rDNA NGS showed deep variations in the composition in the different mice groups. Furthermore, differences were observed in the gene expression of relevant immunological mediators, such as IL4, CXCL15, IL13, TNFα and TLR2, at the small intestine. Our results suggest that microbiota depletion eliminates bacteria that restrict HuNoVs infectivity and that the mechanism(s) could involve immune mediators.

Infant Gut Microbial Metagenome Mining of α-l-Fucosidases with Activity on Fucosylated Human Milk Oligosaccharides and Glycoconjugates.

The gastrointestinal microbiota members produce α-l-fucosidases that play key roles in mucosal, human milk, and dietary oligosaccharide assimilation. Here, 36 open reading frames (ORFs) coding for putative α-l-fucosidases belonging to glycosyl hydrolase family 29 (GH29) were identified through metagenome analysis of breast-fed infant fecal microbiome. Twenty-two of those ORFs showed a complete coding sequence with deduced amino acid sequences displaying the highest degree of identity with α-l-fucosidases from Bacteroides thetaiotaomicron, Bacteroides caccae, Phocaeicola vulgatus, Phocaeicola dorei, Ruminococcus gnavus, and Streptococcus parasanguinis. Based on sequence homology, 10 α-l-fucosidase genes were selected for substrate specificity characterization. The α-l-fucosidases Fuc18, Fuc19A, Fuc35B, Fuc39, and Fuc1584 showed hydrolytic activity on α1,3/4-linked fucose present in Lewis blood antigens and the human milk oligosaccharide (HMO) 3-fucosyllactose. In addition, Fuc1584 also hydrolyzed fucosyl-α-1,6-N-acetylglucosamine (6FN), a component of the core fucosylation of N-glycans. Fuc35A and Fuc193 showed activity on α1,2/3/4/6 linkages from H type-2, Lewis blood antigens, HMOs and 6FN. Fuc30 displayed activity only on α1,6-linked l-fucose, and Fuc5372 showed a preference for α1,2 linkages. Fuc2358 exhibited a broad substrate specificity releasing l-fucose from all the tested free histo-blood group antigens, HMOs, and 6FN. This latest enzyme also displayed activity in glycoconjugates carrying lacto-N-fucopentaose II (Lea) and lacto-N-fucopentaose III (Lex) and in the glycoprotein mucin. Fuc18, Fuc19A, and Fuc39 also removed l-fucose from neoglycoproteins and human α-1 acid glycoprotein. These results give insight into the great diversity of α-l-fucosidases from the infant gut microbiota, thus supporting the hypothesis that fucosylated glycans are crucial for shaping the newborn microbiota composition. IMPORTANCE α-l-Fucosyl residues are frequently present in many relevant glycans, such as human milk oligosaccharides (HMOs), histo-blood group antigens (HBGAs), and epitopes on cell surface glycoconjugate receptors. These fucosylated glycans are involved in a number of mammalian physiological processes, including adhesion of pathogens and immune responses. The modulation of l-fucose content in such processes may provide new insights and knowledge regarding molecular interactions and may help to devise new therapeutic strategies. Microbial α-l-fucosidases are exoglycosidases that remove α-l-fucosyl residues from free oligosaccharides and glycoconjugates and can be also used in transglycosylation reactions to synthesize oligosaccharides. In this work, α-l-fucosidases from the GH29 family were identified and characterized from the metagenome of fecal samples of breastfed infants. These enzymes showed different substrate specificities toward HMOs, HBGAs, naturally occurring glycoproteins, and neoglycoproteins. These novel glycosidase enzymes from the breast-fed infant gut microbiota, which resulted in a good source of α-l-fucosidases, have great biotechnological potential.

Limited contribution of post-fire eco-engineering techniques to support post-fire plant diversity.

Eco-engineering techniques are generally effective at reducing soil erosion and restore vegetal cover after wildfire. However, less evidence exists on the effects of the post-fire eco-engineering techniques to restore plant diversity. To fill this knowledge gap, a standardized regional-scale analysis of the influence of post-fire eco-engineering techniques (log erosion barriers, contour felled log debris, mulching, chipping and felling, in some cases with burning) on species richness and diversity is proposed, adopting the Iberian Peninsula as case study. In general, no significant differences in species richness and diversity (Shannon) were found between the forest treated with different post-fire eco-engineering techniques, and the burned and non-treated soils. Only small significant differences were found for some sites treated with log erosion barriers or mulching. The latter technique increased species richness and diversity in some pine species and shrublands. Contour felled log debris with burning slightly increased vegetation diversity, while log erosion barriers, chipping and felling were not successful in supporting plant diversity. This research will help forest managers and agents in Mediterranean forest to decide the best postfire management option for wildfire affected forest, and in the development of more effective post-fire strategies.

Coupling time-lapse ground penetrating radar surveys and infiltration experiments to characterize two types of non-uniform flow.

Understanding linkages between heterogeneous soil structures and non-uniform flow is fundamental for interpreting infiltration processes and improving hydrological simulations. Here, we utilized ground-penetrating radar (GPR) as a non-invasive technique to investigate those linkages and to complement current traditional methods that are labor-intensive, invasive, and non-repeatable. We combined time-lapse GPR surveys with different types of infiltration experiments to create three-dimensional (3D) diagrams of the wetting dynamics. We carried out the GPR surveys and validated them with in situ observations, independent measurements and field excavations at two experimental sites. Those sites were selected to represent different mechanisms that generate non-uniform flow: (1) preferential water infiltration initiated by tree trunk and root systems; and (2) lateral subsurface flow due to soil layering. Results revealed links between different types of soil heterogeneity and non-uniform flow. The first experimental site provided evidence of root-induced preferential flow paths along coarse roots, emphasizing the important role of coarse roots in facilitating preferential water movement through the subsurface. The second experimental site showed that water infiltrated through the restrictive layer mainly following the plant root system. The presented approach offers a non-invasive, repeatable and accurate way to detect non-uniform flow.

Infant-gut associated Bifidobacterium dentium strains utilize the galactose moiety and release lacto-N-triose from the human milk oligosaccharides lacto-N-tetraose and lacto-N-neotetraose.

Much evidence suggests a role for human milk oligosaccharides (HMOs) in establishing the infant microbiota in the large intestine, but the response of particular bacteria to individual HMOs is not well known. Here twelve bacterial strains belonging to the genera Bifidobacterium, Enterococcus, Limosilactobacillus, Lactobacillus, Lacticaseibacillus, Staphylococcus and Streptococcus were isolated from infant faeces and their growth was analyzed in the presence of the major HMOs, 2'-fucosyllactose (2'FL), 3-fucosyllactose (3FL), 2',3-difucosyllactose (DFL), lacto-N-tetraose (LNT) and lacto-N-neo-tetraose (LNnT), present in human milk. Only the isolated Bifidobacterium strains demonstrated the capability to utilize these HMOs as carbon sources. Bifidobacterium infantis Y538 efficiently consumed all tested HMOs. Contrarily, Bifidobacterium dentium strains Y510 and Y521 just metabolized LNT and LNnT. Both tetra-saccharides are hydrolyzed into galactose and lacto-N-triose (LNTII) by B. dentium. Interestingly, this species consumed only the galactose moiety during growth on LNT or LNnT, and excreted the LNTII moiety. Two ß-galactosidases were characterized from B. dentium Y510, Bdg42A showed the highest activity towards LNT, hydrolyzing it into galactose and LNTII, and Bdg2A towards lactose, degrading efficiently also 6'-galactopyranosyl-N-acetylglucosamine, N-acetyl-lactosamine and LNnT. The work presented here supports the hypothesis that HMOs are mainly metabolized by Bifidobacterium species in the infant gut.

Three-Flap Mastopexy with Reduction or Augmentation.

BACKGROUND: Many authors have studied breast ptosis and made contributions to the search for a procedure that allows its correction with long-lasting results and minimal scars. Collective evolution has allowed us to reach the point where we are today and will allow us to continue improving techniques in the future. OBJECTIVES: The mastopexy procedure that we have used for the last 11 years, resulting from our surgical practice and countless observations at conferences, is a versatile procedure, applicable to different types of breasts and mastopexies with and without reduction or augmentation. METHODS: Analysis and the clinical review of the patients and the records of the mastopexy cases that we operated on using the technique from January 2009 to March, 2020, are presented here. Using a periareolar approach for grade I ptosis and an inverted "T" approach for more severe ptosis, the excess skin is removed, and three flaps of breast tissue, superior, medial and lateral, are carved. A retromammary dissection is performed to anchor the end of the flaps, medial and lateral, to the pectoral aponeurosis, followed by invagination of these flaps to concentrate the breast tissue in the upper and central area of the breast. Closure of the wound is then performed, transforming its excess length into a short horizontal one, into the inframammary grove. RESULTS: Sixty-seven female patients, between 36 and 59 years old, underwent this procedure. Complications included hematoma (4%), overcorrection (4%), dehiscence (3.3%), residual ptosis (2.7%), pathological scarring (2.7%) and rotation folds (2%). Maximum follow-up was 8 years 2 months, mean follow-up 2 years 9 months, with satisfactory results for the patients and surgeon. CONCLUSIONS: The mastopexy procedure that we present here is a versatile technique, which can be applied to most cases requiring correction of ptosis. It provides the breast with proper shape, size and location with fewer scars. It is a logical, safe, efficient, reproducible procedure, which is easy to learn. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Microbiota Depletion Promotes Human Rotavirus Replication in an Adult Mouse Model.

Intestinal microbiota-virus-host interaction has emerged as a key factor in mediating enteric virus pathogenicity. With the aim of analyzing whether human gut bacteria improve the inefficient replication of human rotavirus in mice, we performed fecal microbiota transplant (FMT) with healthy infants as donors in antibiotic-treated mice. We showed that a simple antibiotic treatment, irrespective of FMT, resulted in viral shedding for 6 days after challenge with the human rotavirus G1P[8] genotype Wa strain (RVwa). Rotavirus titers in feces were also significantly higher in antibiotic-treated animals with or without FMT but they were decreased in animals subject to self-FMT, where a partial re-establishment of specific bacterial taxons was evidenced. Microbial composition analysis revealed profound changes in the intestinal microbiota of antibiotic-treated animals, whereas some bacterial groups, including members of Lactobacillus, Bilophila, Mucispirillum, and Oscillospira, recovered after self-FMT. In antibiotic-treated and FMT animals where the virus replicated more efficiently, differences were observed in gene expression of immune mediators, such as IL1ß and CXCL15, as well as in the fucosyltransferase FUT2, responsible for H-type antigen synthesis in the small intestine. Collectively, our results suggest that antibiotic-induced microbiota depletion eradicates the microbial taxa that restrict human rotavirus infectivity in mice.

Assessing reforestation failure at the project scale: The margin for technical improvement under harsh conditions. A case study in a Mediterranean Dryland.

Poor reforestation outcomes imply failure to fulfill program goals and tend to erode institutional willpower and political momentum towards reforestation efforts, affecting both public and private support. However, program improvement in real reforestation projects is challenging, due to the conjunction of many different variables that mutually interact and feed back on each other inextricably. This study develops a comprehensive assessment framework for reforestation programs, for which technical and environmental information is gathered and related to indicators of performance in both the short- and mid-term. This assessment, tested on a case study, aimed to provide reliable end-results for survival and growth, revealed pitfalls in successful plantation establishment and taught us how to improve plantation performance and what the margin for this improvement was. The selected project was carried out on harsh site conditions, with different species, cultivation treatments and contractors, and was affected by the driest year on record. Plantation mortality was high and increased progressively over time, particularly in the short-term when the rate was 53% (rising to 83% after ten years), showing high variation between sites and species (Pinus pinaster and Quercus faginea died more than 94% after ten years while Junipus phoenicea only 40%). All the hardwoods and the juniper showed lower growth rate after ten years (average stem volume < 40 cm3) than pines (stem volume > 470 cm3). Technical variables (project planning and execution) had a relatively important impact on plantation performance in the first two years (11-29%), but decreased with time, whilst environmental variables (site and meteorological) were more important ten years after planting (>50%). In the short-term, soil moisture and meteorology during the planting season were identified as key factors that triggered the effects of both technical decisions (planting date and planting technique) and other environmental variables on performance. In the design phase, some decisions related to zoning, species selection and cultural treatments were related to poor performance. The results provide practical information and guidelines about all potential drivers of plantation performance and contribute to identify those aspects more related to success of forest restoration in Mediterranean drylands.

Infant gut microbiota modulation by human milk disaccharides in humanized microbiome mice.

Human milk glycans present a unique diversity of structures that suggest different mechanisms by which they may affect the infant microbiome development. A humanized mouse model generated by infant fecal transplantation was utilized here to evaluate the impact of fucosyl-α1,3-GlcNAc (3FN), fucosyl-α1,6-GlcNAc, lacto-N-biose (LNB) and galacto-N-biose on the fecal microbiota and host-microbiota interactions. 16S rRNA amplicon sequencing showed that certain bacterial genera significantly increased (Ruminococcus and Oscillospira) or decreased (Eubacterium and Clostridium) in all disaccharide-supplemented groups. Interestingly, cluster analysis differentiates the consumption of fucosyl-oligosaccharides from galactosyl-oligosaccharides, highlighting the disappearance of Akkermansia genus in both fucosyl-oligosaccharides. An increment of the relative abundance of Coprococcus genus was only observed with 3FN. As well, LNB significantly increased the relative abundance of Bifidobacterium, whereas the absolute levels of this genus, as measured by quantitative real-time PCR, did not significantly increase. OTUs corresponding to the species Bifidobacterium longum, Bifidobacterium adolescentis and Ruminococcus gnavus were not present in the control after the 3-week intervention, but were shared among the donor and specific disaccharide groups, indicating that their survival is dependent on disaccharide supplementation. The 3FN-feeding group showed increased levels of butyrate and acetate in the colon, and decreased levels of serum HDL-cholesterol. 3FN also down-regulated the pro-inflammatory cytokine TNF-α and up-regulated the anti-inflammatory cytokines IL-10 and IL-13, and the Toll-like receptor 2 in the large intestine tissue. The present study revealed that the four disaccharides show efficacy in producing beneficial compositional shifts of the gut microbiota and in addition, the 3FN demonstrated physiological and immunomodulatory roles.

Efectos del ultrasonido externo sobre el panículo adiposo. Modelo porcino experimental / Effects of external ultrasound on the adipose panicle. Experimental pig model

INTRODUCCIÓN Y OBJETIVO: El ultrasonido (US) externo o percutáneo, ampliamente utilizado, ocasiona diferentes efectos histológicos dependiendo de la frecuencia, intensidad, amplitud de onda, tiempo de aplicación y de los tejidos a través de los cuales curse. Se ha utilizado con diferentes propósitos, entre otros para facilitar la liposucción y mejorar sus resultados; sin embargo, hasta donde hemos podido revisar, no hay reportes que relacionen las frecuencias del US percutáneo y el lapso de su aplicación con los cambios descritos en el panículo adiposo. El objetivo del presente estudio es establecer parámetros de frecuencia y tiempos de aplicación del US externo para uniformar criterios en base al análisis histológico de los cambios que ocasiona al panículo adiposo y a los adipocitos. MATERIAL Y MÉTODO: Estudio descriptivo, comparativo, abierto, experimental, prospectivo y longitudinal, en 59 fragmentos de tejido adiposo tomados de cerdos adultos. Cinco fragmentos fueron preservados como control; los 54 restantes fueron sometidos a US directo sobre cada fragmento, con diferentes parámetros de tiempo (5, 10 y 15 minutos) y diferentes frecuencias (baja- 1.1 Hz, media- 2.4 Hz y alta- 3.9 Hz). Fueron procesados en 2 formas (parafina y congelación) y teñidos con 2 técnicas (hematoxilina/eosina y rojo oleoso). En cada laminilla se observaron 10 campos. RESULTADOS: En los fragmentos de control observamos tejido adiposo maduro normal. En los sometidos a US, dependiendo de la frecuencia y el tiempo aplicado, observamos edema intersticial, desarreglo de su arquitectura, lisis de la membrana de los adipocitos e infiltrado inflamatorio, en diversos porcentajes, que calificamos en grados. Así en los fragmentos expuestos durante 5 minutos a frecuencia media hubo lisis leve (10%), igual que en los expuestos 10 minutos a frecuencia baja. En los expuestos 10 minutos a frecuencia media la lisis fue de leve a moderada (10-20%), semejante a la observada con frecuencia baja durante 15 minutos. Aplicando US durante 15 minutos con frecuencia baja la respuesta fue de leve a moderada (10-20%), con frecuencia media fue de moderada a severa (20-30%) y con frecuencia alta fue francamente severa (30%). CONCLUSIONES: La aplicación de US externo ocasiona lisis de los adipocitos y evidentes desarreglos en la arquitectura del tejido adiposo. Aplicarlo con frecuencias menores requiere periodos más largos para lograr los mismos efectos. Con frecuencias mayores se logran los cambios en menos tiempo. El empleo de frecuencias de 2.4 a 3.9 Hz ocasiona cambios evidentes, con amplio margen de seguridad

BACKGROUND AND OBJECTIVE: External or percutaneous ultrasound (US) widely used, causes different histological effects depending on the frequency, intensity, wave amplitude, application time and the tissues through which it passes. It has been used for different purposes, among others, to facilitate liposuction and improve its results; however, as far as we have been able to review, there are no reports that relate the frequencies of the percutaneous US and the period of its application with the changes described in the adipose tissue. Our aim is to establish frequency parameters and application times of the external US to standardize criteria, based on the histological analysis of the changes it causes to the adipose panniculus and to the adipocytes. METHODS: A descriptive, comparative, open, experimental, prospective and longitudinal study was carried out in 59 fragments of adipose tissue taken from adult pigs. Fifty-four were subjected to US applied directly to each fragment, with different time parameters (5, 10 and 15 minutes) and different frequencies (low-1.1 Hz, medium-2.4 Hz and high-3.9 Hz). Five fragments were preserved as a control. Processed in 2 ways (paraffin and freezing) and stained with 2 techniques (hematoxylin/eosin and oil red). In each lamella 10 fields were observed. RESULTS: Normal mature adipose tissue was observed in the control fragments. In those undergoing US, depending on the frequency and time applied, interstitial edema, disordered architecture, presence of inflammatory infiltrate and lysis of adipocyte membranes were observed, in various percentages that we qualified in degrees. Thus, in the fragments exposed for 5 minutes at medium frequency, mild lysis was observed (10%), In those exposed for 10 minutes at medium frequency, lysis was mild to moderate ( 10-20%), similar to that observed with low frequency for 15 minutes. Applying US for 15 minutes with low frequency, the response was mild to moderate (10-20%) with medium frequency of moderate to severe (20-30%) and with high frequency it was frankly severe (30%). CONCLUSIONS: The application of external US causes lysis of the adipocytes and evident disorders in the adipose tissue architecture. Applying it with lower frequencies requires longer periods to achieve the same effects. With higher frequencies the same changes are achieved in less time. The use of frequencies from 2.4 to 3.9 Hz causes obvious changes, with a wide margin of safety

Interaction of Intestinal Bacteria with Human Rotavirus during Infection in Children.

The gut microbiota has emerged as a key factor in the pathogenesis of intestinal viruses, including enteroviruses, noroviruses and rotaviruses (RVs), where stimulatory and inhibitory effects on infectivity have been reported. With the aim of determining whether members of the microbiota interact with RVs during infection, a combination of anti-RV antibody labeling, fluorescence-activated cell sorting and 16S rRNA amplicon sequencing was used to characterize the interaction between specific bacteria and RV in stool samples of children suffering from diarrhea produced by G1P[8] RV. The genera Ruminococcus and Oxalobacter were identified as RV binders in stools, displaying enrichments between 4.8- and 5.4-fold compared to samples nonlabeled with anti-RV antibodies. In vitro binding of the G1P[8] Wa human RV strain to two Ruminococcus gauvreauii human isolates was confirmed by fluorescence microscopy. Analysis in R. gauvreauii with antibodies directed to several histo-blood group antigens (HBGAs) indicated that these bacteria express HBGA-like substances on their surfaces, which can be the target for RV binding. Furthermore, in vitro infection of the Wa strain in differentiated Caco-2 cells was significantly reduced by incubation with R. gauvreauii. These data, together with previous findings showing a negative correlation between Ruminococcus levels and antibody titers to RV in healthy individuals, suggest a pivotal interaction between this bacterial group and human RV. These results reveal likely mechanisms of how specific bacterial taxa of the intestinal microbiota could negatively affect RV infection and open new possibilities for antiviral strategies.

Responses of forest carbon and water coupling to thinning treatments from leaf to stand scales in a young montane pine forest.

BACKGROUND: Water-use efficiency (WUE) represents the coupling of forest carbon and water. Little is known about the responses of WUE to thinning at multiple spatial scales. The objective of this research was to use field measurements to understand short-term effects of two thinning treatments (T1: 4500 stems ha-1; and T2: 1100 stems ha-1) and the control (NT: 27,000 stems ha-1) on WUE at the three spatial scales (leaf level: the ratio of leaf photosynthesis to leaf transpiration; tree-level: tree growth to tree transpiration; and stand level: net primary production (NPP) to stand transpiration) and intrinsic WUEi (the ratio of leaf photosynthesis to stomatal conductance at leaf-level; and NPP to canopy conductance at stand-level) in a 16-year old natural lodgepole pine forest. Leaf-level measurements were conducted in 2017, while tree- and stand-level measurements were conducted in both 2016 (the normal precipitation year) and 2017 (the drought year). RESULTS: The thinning treatments did not significantly affect the tree- and stand-level WUE in the normal year of 2016. However, the thinning significantly affected WUE in the drought year of 2017: T2 exhibited significantly higher tree-level WUE (0.49 mm2 kg-1) than NT (0.08 mm2 kg-1), and compared to NT, the stand-level WUE values in the thinned stands (T1 and T2) were significantly higher, with means of 0.31, 0.56 and 0.70 kg m-3, respectively. However, the leaf-level and stand-level WUEi in the thinned stands in the drought year were significantly lower than those in the unthinned stands. No significant differences in the leaf-level WUE were found among the treatments in 2017. In addition, the thinning did not significantly change the WUE-VPD relationships at any studied spatial scale. CONCLUSIONS: The thinning treatments did not cause significant changes in all studied WUE metrics in a normal year. However, their effects were significantly promoted under the drought conditions probably due to the decrease in soil water availability, demonstrating that thinning can improve WUE and consequently support forests to cope with the drought effects. The inconsistent results on the effects of the thinning on forest carbon and water coupling at the spatial scales and the lack of the consistent WUE metrics constraint across-scale comparison and transferring of WUE.

Human milk and mucosa-associated disaccharides impact on cultured infant fecal microbiota.

Human milk oligosaccharides (HMOs) are a mixture of structurally diverse carbohydrates that contribute to shape a healthy gut microbiota composition. The great diversity of the HMOs structures does not allow the attribution of specific prebiotic characteristics to single milk oligosaccharides. We analyze here the utilization of four disaccharides, lacto-N-biose (LNB), galacto-N-biose (GNB), fucosyl-α1,3-GlcNAc (3FN) and fucosyl-α1,6-GlcNAc (6FN), that form part of HMOs and glycoprotein structures, by the infant fecal microbiota. LNB significantly increased the total levels of bifidobacteria and the species Bifidobacterium breve and Bifidobacterium bifidum. The Lactobacillus genus levels were increased by 3FN fermentation and B. breve by GNB and 3FN. There was a significant reduction of Blautia coccoides group with LNB and 3FN. In addition, 6FN significantly reduced the levels of Enterobacteriaceae family members. Significantly higher concentrations of lactate, formate and acetate were produced in cultures containing either LNB or GNB in comparison with control cultures. Additionally, after fermentation of the oligosaccharides by the fecal microbiota, several Bifidobacterium strains were isolated and identified. The results presented here indicated that each, LNB, GNB and 3FN disaccharide, might have a specific beneficial effect in the infant gut microbiota and they are potential prebiotics for application in infant foods.

Sero-epidemiological study of the rotavirus VP8* protein from different P genotypes in Valencia, Spain.

The aims of the present work were to determine the prevalence and titer of serum antibodies against several rotavirus VP8* proteins from different P genotypes in children and adults in Valencia, Spain; and to determine the role of the secretor status (FUT2G428A polymorphism) in the antibody response. The VP8* protein from the P[4], P[6], P[8], P[9], P[11], P[14] and P[25] genotypes were produced in E. coli. These proteins were tested with 88 serum samples from children (n = 41, 3.5 years old in average) and from adults (n = 47, 58 years old in average) by ELISA. A subset of 55 samples were genotyped for the FUT2G428A polymorphism and the antibody titers compared. The same subset of samples was also analysed by ELISA using whole rotavirus Wa particles (G1P[8]) as antigen. Ninety-three per cent of the samples were positive for at least one of the VP8* antigens. Differences in the IgG seroprevalence were found between children and adults for the P[4], P[8] and P[11] genotypes. Similarly, significant differences were found between adults and children in their antibody titers against the P[4], P[8], and P[11] VP8* genotypes, having the children higher antibody titers than adults. Interestingly, positive samples against rare genotypes such as P[11] (only in children), P[14] and P[25] were found. While no statistical differences in the antibody titers between secretors and non-secretors were found for any of the tested P genotypes studied, a higher statistic significant prevalence for the P[25] genotype was found in secretors compared to non-secretors. Significant differences in the antibody titers between secretors and non-secretors were found when the whole viral particles from the Wa rotavirus strain (G1P[8]) were used as the antigen.