Phenotypic characterization of liver tissue heterogeneity through a next-generation 3D single-cell atlas.

Three-dimensional (3D) geometrical models are potent tools for quantifying complex tissue features and exploring structure-function relationships. However, these models are generally incomplete due to experimental limitations in acquiring multiple (> 4) fluorescent channels in thick tissue sections simultaneously. Indeed, predictive geometrical and functional models of the liver have been restricted to few tissue and cellular components, excluding important cellular populations such as hepatic stellate cells (HSCs) and Kupffer cells (KCs). Here, we combined deep-tissue immunostaining, multiphoton microscopy, deep-learning techniques, and 3D image processing to computationally expand the number of simultaneously reconstructed tissue structures. We then generated a spatial single-cell atlas of hepatic architecture (Hep3D), including all main tissue and cellular components at different stages of post-natal development in mice. We used Hep3D to quantitatively study 1) hepatic morphodynamics from early post-natal development to adulthood, and 2) the effect on the liver's overall structure when changing the hepatic environment after removing KCs. In addition to a complete description of bile canaliculi and sinusoidal network remodeling, our analysis uncovered unexpected spatiotemporal patterns of non-parenchymal cells and hepatocytes differing in size, number of nuclei, and DNA content. Surprisingly, we found that the specific depletion of KCs results in morphological changes in hepatocytes and HSCs. These findings reveal novel characteristics of liver heterogeneity and have important implications for both the structural organization of liver tissue and its function. Our next-gen 3D single-cell atlas is a powerful tool to understand liver tissue architecture, opening up avenues for in-depth investigations into tissue structure across both normal and pathological conditions.

Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) for the diagnosis of delirium in adults in critical care settings.

BACKGROUND: Delirium is an underdiagnosed clinical syndrome typified by an acute alteration of mental state. It is an important problem in critical care and intensive care units (ICU) due to its high prevalence and its association with adverse outcomes. Delirium is a very distressing condition for patients, with a huge impact on their well-being. Diagnosis of delirium in the critical care setting is challenging. This is especially true for patients who are mechanically ventilated and are therefore unable to engage in a verbal interview. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a tool specifically designed to assess for delirium in the context of ICU patients, including those on mechanical ventilation. CAM-ICU can be administered by non-specialists to give a dichotomous delirium present/absent result. OBJECTIVES: To determine the diagnostic accuracy of the CAM-ICU for the diagnosis of delirium in adult patients in critical care units. SEARCH METHODS: We searched MEDLINE (Ovid SP, 1946 to 8 July 2022), Embase (Ovid SP, 1982 to 8 July 2022), Web of Science Core Collection (ISI Web of Knowledge, 1945 to 8 July 2022), PsycINFO (Ovid SP, 1806 to 8 July 2022), and LILACS (BIREME, 1982 to 8 July 2022). We checked the reference lists of included studies and other resources for additional potentially relevant studies. We also searched the Health Technology Assessment database, the Cochrane Library, Aggressive Research Intelligence Facility database, WHO ICTRP, ClinicalTrials.gov, and websites of scientific associations to access any annual meetings and abstracts of conference proceedings in the field. SELECTION CRITERIA: We included diagnostic studies enrolling adult ICU patients assessed using the CAM-ICU tool, regardless of language or publication status and reporting sufficient data on delirium diagnosis for the construction of 2 x 2 tables. Eligible studies evaluated the diagnostic performance of the CAM-ICU versus a clinical reference standard based on any iteration of the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria applied by a clinical expert. DATA COLLECTION AND ANALYSIS: Two review authors independently selected and collated study data. We assessed the methodological quality of studies using the QUADAS-2 tool. We used two univariate fixed-effect or random-effects models to determine summary estimates of sensitivity and specificity. We performed sensitivity analyses that excluded studies considered to be at high risk of bias and high concerns in applicability, due mainly to the target population included (e.g. patients with traumatic brain injury). We also investigated potential sources of heterogeneity, assessing the effect of reference standard diagnosis and proportion of patients ventilated. MAIN RESULTS: We included 25 studies (2817 participants). The mean age of participants ranged from 48 to 69 years; 15 of the studies included critical care units admitting mixed populations (e.g. medical, trauma, surgery patients). The percentage of patients receiving mechanical ventilation ranged from 11.8% to 100%. The prevalence of delirium in the studies included ranged from 12.5% to 83.9%. Presence of delirium was determined by the application of DSM-IV criteria in 13 out of 25 included studies. We assessed 13 studies as at low risk of bias and low applicability concerns for all QUADAS-2 domains. The most common issue of concern was flow and timing of the tests, followed by patient selection. Overall, we estimated a pooled sensitivity of 0.78 (95% confidence interval (CI) 0.72 to 0.83) and a pooled specificity of 0.95 (95% CI 0.92 to 0.97). Sensitivity analysis restricted to studies at low risk of bias and without any applicability concerns (n = 13 studies) gave similar summary accuracy indices (sensitivity 0.80 (95% CI 0.72 to 0.86), specificity 0.95 (95% CI 0.93 to 0.97)). Subgroup analyses based on diagnostic assessment found summary estimates of sensitivity and specificity for studies using DSM-IV of 0.79 (95% CI 0.72 to 0.85) and 0.94 (95% CI 0.90 to 0.96). For studies that used DSM-5 criteria, summary estimates of sensitivity and specificity were 0.75 (95% CI 0.67 to 0.82) and 0.98 (95% CI 0.95 to 0.99). DSM criteria had no significant effect on sensitivity (P = 0.421), but the specificity for detection of delirium was higher when DSM-5 criteria were used (P = 0.024). The relative specificity comparing DSM-5 versus DSM-IV criteria was 1.05 (95% CI 1.02 to 1.08). Summary estimates of sensitivity and specificity for studies recruiting < 100% of patients with mechanical ventilation were 0.81 (95% CI 0.75 to 0.85) and 0.95 (95% CI 0.91 to 0.98). For studies that exclusively recruited patients with mechanical ventilation, summary estimates of sensitivity and specificity were 0.91 (95% CI 0.76 to 0.97) and 0.98 (95% CI 0.92 to 0.99). Although there was a suggestion of differential performance of CAM-ICU in ventilated patients, the differences were not significant in sensitivity (P = 0.316) or in specificity (P = 0.493). AUTHORS' CONCLUSIONS: The CAM-ICU tool may have a role in the early identification of delirium, in adult patients hospitalized in intensive care units, including those on mechanical ventilation, when non-specialized, properly trained clinical personnel apply the CAM-ICU. The test is most useful for exclusion of delirium. The test may miss a proportion of patients with incident delirium, therefore in situations where detection of all delirium cases is desirable, it may be best to repeat the test or combine CAM-ICU with another assessment. Future studies should compare different screening tests proposed for bedside assessment of delirium, as this approach will reveal which tool yields superior accuracy. In addition, future studies should consider and report the flow and timing of the tests and clearly report key characteristics related to patient selection. Finally, future research should focus on the impact of CAM-ICU screening on patient outcomes.

"Unraveling the Gut Microbiome of the Genus Herichthys (Pisces: Cichlidae): What Can We Learn from Museum Specimens?"

The use of museum preserved specimens to know microbiome in extinct and threatened species has been explored recently. The fishes of the genus Herichthys are distributed mainly in the Pánuco-Tamesí system in Northeastern Mexico, one of the most polluted basins in the country leading to near half of the species be considering as threatened. In this paper we used the hypervariable V4 region of the 16S rRNA gene from the 11 species of the genus Herichthys obtained from museum collections to evaluate the potential use of fixed preserved vouchers in the knowledge of gut microbiota diversity and the potential role of sympatric and allopatric speciation of the hosts in the gut microbiome evolution. The 100% of the samples were successfully amplified where the number of amplicons ranged from 4500 from a formaldehyde fixed specimen up to 55,000 in ethanol preserved specimens. Differences in gut microbiota were found between sympatric species and among the comparison of some trophic guilds. A non-random association between the gut host and their microbiome was found allow to suggest a potential phylosymbiosis relationship. In conclusion, the most abundant phyla recovered from the gut microbiota in this study were similar to those previously reported in other cichlids supporting the idea that a gut microbial core is conserved in this group of fishes despite millions of years of evolution and leading to support the potential use of museum specimens in microbiome studies.

Clinical characteristics and in-hospital mortality of patients with COVID-19 in Chile: A prospective cohort study.

AIMS OF THIS STUDY: To describe the Latin American population affected by COVID-19, and to determine relevant risk factors for in-hospital mortality. METHODS: We prospectively registered relevant clinical, laboratory, and radiological data of adult patients with COVID-19, admitted within the first 100 days of the pandemic from a single teaching hospital in Santiago, Chile. The primary outcome was in-hospital mortality. Secondary outcomes included the need for respiratory support and pharmacological treatment, among others. We combined the chronic disease burden and the severity of illness at admission with predefined clinically relevant risk factors. Cox regression models were used to identify risk factors for in-hospital mortality. RESULTS: We enrolled 395 adult patients, their median age was 61 years; 62.8% of patients were male and 40.1% had a Modified Charlson Comorbidity Index (MCCI) ≥5. Their median Sequential Organ Failure Assessment (SOFA) score was 3; 34.9% used a high-flow nasal cannula and 17.5% required invasive mechanical ventilation. The in-hospital mortality rate was 14.7%. In the multivariate analysis, were significant risk factors for in-hospital mortality: MCCI ≥5 (HR 4.39, P < .001), PaO2 /FiO2 ratio ≤200 (HR 1.92, P = .037), and advanced chronic respiratory disease (HR 3.24, P = .001); pre-specified combinations of these risk factors in four categories was associated with the outcome in a graded manner. CONCLUSIONS AND CLINICAL IMPLICATIONS: The relationship between multiple prognostic factors has been scarcely reported in Latin American patients with COVID-19. By combining different clinically relevant risk factors, we can identify COVID-19 patients with high-, medium- and low-risk of in-hospital mortality.

Correction: Quantification of nematic cell polarity in three-dimensional tissues.

[This corrects the article DOI: 10.1371/journal.pcbi.1008412.].

Incident adverse drug reactions and their effect on the length of hospital stay in older inpatients.

Background Acutely ill older persons are more likely to suffer adverse drug reactions, increasing morbidity, and mortality. The incident adverse drug reactions and their consequences on the length of hospital stay (LOS) in older persons have been little explored. Objective To determine the incident adverse drug reactions in acutely ill older inpatients and their effect on the LOS. Setting Internal medicine service in a Chilean teaching hospital. Method A prospective cohort study was conducted in patients aged ≥ 60 years admitted into the internal medicine service of the Hospital from University of Chile. Characteristics, severity, and causality of adverse drug reactions were assessed. Effect of incident adverse drug reactions on the LOS was determined using multiple Cox regression. A secondary analysis was conducted in patients aged ≥ 65 years. Main outcome measure Incident adverse drug reactions (new events occurring in hospital) and their effect on the LOS in older inpatients. Results A total of 229 acutely ill older persons ≥ 60 years were followed-up. Fifty-six of them suffered 77 adverse drug reactions (incident rate 24.5%; 95% CI: 19.0, 30.5), 70.1% type A. Adverse drug reactions were severe in 5.4% of cases. Causality assessment indicated the majority were probable (57.1%) and 3.9% certain. Cardiovascular agents were the therapeutic class more frequently involved. The most frequent adverse drug reaction was hypotension (19.5%). Patients with adverse drug reactions had a significantly prolonged LOS than those without adverse drug reactions (12.4 ± 11.0 versus 7.3 ± 6.4 days; p < 0.0001) (adjusted Hazard Ratio 0.63; 95% CI: 0.46, 0.87; p < 0.01), respectively. The incidence rate of adverse drug reactions in patients ≥ 65 years was 25.1% (95% CI: 19.0; 32.1), and their occurrence was significantly associated with a prolonged LOS (p < 0.05). Conclusion One in four acutely ill older persons hospitalized in the internal medicine service suffered at least one incident adverse drug reaction, which prolonged the LOS by 5 days. There is a potential to optimize the use of hospital beds and medication safety by preventing adverse drug reactions in geriatric patients.

Quantification of nematic cell polarity in three-dimensional tissues.

How epithelial cells coordinate their polarity to form functional tissues is an open question in cell biology. Here, we characterize a unique type of polarity found in liver tissue, nematic cell polarity, which is different from vectorial cell polarity in simple, sheet-like epithelia. We propose a conceptual and algorithmic framework to characterize complex patterns of polarity proteins on the surface of a cell in terms of a multipole expansion. To rigorously quantify previously observed tissue-level patterns of nematic cell polarity (Morales-Navarrete et al., eLife 2019), we introduce the concept of co-orientational order parameters, which generalize the known biaxial order parameters of the theory of liquid crystals. Applying these concepts to three-dimensional reconstructions of single cells from high-resolution imaging data of mouse liver tissue, we show that the axes of nematic cell polarity of hepatocytes exhibit local coordination and are aligned with the biaxially anisotropic sinusoidal network for blood transport. Our study characterizes liver tissue as a biological example of a biaxial liquid crystal. The general methodology developed here could be applied to other tissues and in-vitro organoids.

Neuronal surface P antigen (NSPA) modulates postsynaptic NMDAR stability through ubiquitination of tyrosine phosphatase PTPMEG.

BACKGROUND: Cognitive dysfunction (CD) is common among patients with the autoimmune disease systemic lupus erythematosus (SLE). Anti-ribosomal P autoantibodies associate with this dysfunction and have neuropathogenic effects that are mediated by cross-reacting with neuronal surface P antigen (NSPA) protein. Elucidating the function of NSPA can then reveal CD pathogenic mechanisms and treatment opportunities. In the brain, NSPA somehow contributes to glutamatergic NMDA receptor (NMDAR) activity in synaptic plasticity and memory. Here we analyze the consequences of NSPA absence in KO mice considering its structural features shared with E3 ubiquitin ligases and the crucial role of ubiquitination in synaptic plasticity. RESULTS: Electrophysiological studies revealed a decreased long-term potentiation in CA3-CA1 and medial perforant pathway-dentate gyrus (MPP-DG) hippocampal circuits, reflecting glutamatergic synaptic plasticity impairment in NSPA-KO mice. The hippocampal dentate gyrus of these mice showed a lower number of Arc-positive cells indicative of decreased synaptic activity and also showed proliferation defects of neural progenitors underlying less adult neurogenesis. All this translates into poor spatial and recognition memory when NSPA is absent. A cell-based assay demonstrated ubiquitination of NSPA as a property of RBR-type E3 ligases, while biochemical analysis of synaptic regions disclosed the tyrosine phosphatase PTPMEG as a potential substrate. Mice lacking NSPA have increased levels of PTPMEG due to its reduced ubiquitination and proteasomal degradation, which correlated with lower levels of GluN2A and GluN2B NMDAR subunits only at postsynaptic densities (PSDs), indicating selective trafficking of these proteins out of PSDs. As both GluN2A and GluN2B interact with PTPMEG, tyrosine (Tyr) dephosphorylation likely drives their endocytic removal from the PSD. Actually, immunoblot analysis showed reduced phosphorylation of the GluN2B endocytic signal Tyr1472 in NSPA-KO mice. CONCLUSIONS: NSPA contributes to hippocampal plasticity and memory processes ensuring appropriate levels of adult neurogenesis and PSD-located NMDAR. PTPMEG qualifies as NSPA ubiquitination substrate that regulates Tyr phosphorylation-dependent NMDAR stability at PSDs. The NSPA/PTPMEG pathway emerges as a new regulator of glutamatergic transmission and plasticity and may provide mechanistic clues and therapeutic opportunities for anti-P-mediated pathogenicity in SLE, a still unmet need.

Molecular clocks, biogeography and species diversity in Herichthys with evaluation of the role of Punta del Morro as a vicariant brake along the Mexican Transition Zone in the context of local and global time frame of cichlid diversification.

Using molecular dated phylogenies and biogeographic reconstructions, the species diversity, biogeography and time frame of evolution of the genus Herichthys were evaluated. In particular, we test the role of Punta del Morro (PdM) as a vicariant brake along the Mexican Transition Zone in the context of local and global time frame of cichlid diversification using several sets of calibrations. Species diversity in Herichthys is complex and the here employed dating methods suggest young age and rapid divergence for many species while species delimitation methods did not resolve these young species including both sympatric species pairs. Based on our molecular clock dating analyses, Herichthys has colonized its present distribution area significantly prior to the suggested vicariance by PdM (10-17.1 Ma vs. 5 to 7.5 Ma). The PdM constraint is in conflict with all other paleogeographic and fossil constraints including novel ones introduced in this study that are, however, congruent among each other. Our study demonstrates that any cichlid datings significantly older or younger than the bounds presented by our analyses and discussion have to be taken as highly questionable from the point of view of Middle American paleogeography and cichlid biogeography unless we allow the option that cichlid biogeography is completely independent from ecological and geological constraints.

The role of head shape and trophic variation in the diversification of the genus Herichthys in sympatry and allopatry.

In the present study we evaluated the putative cases of sympatric speciation in the genus Herichthys by studying the variation in head shape using principal component analysis, phylomorphospace and reconstructions of the ancestral states of feeding preferences. Herichthys includes both allopatric and sympatric sister species, as well as sympatric unrelated species and thus offers great potential for evolutionary studies of putatively sympatric speciation. Herichthys is the northernmost group of cichlids in America and one of the most ecologically disparate genera within Middle American cichlids. Fifteen anatomical points were recorded on the heads of 293 specimens of the 11 species recognized within the genus. The results show that in spite of having wide variation in consumed diets, most species of Herichthys are close in morphospace. However, morphological variation was great among the two pairs of sympatric sister species in agreement with the suggested sympatric model of speciation.

Three-dimensional spatially resolved geometrical and functional models of human liver tissue reveal new aspects of NAFLD progression.

Early disease diagnosis is key to the effective treatment of diseases. Histopathological analysis of human biopsies is the gold standard to diagnose tissue alterations. However, this approach has low resolution and overlooks 3D (three-dimensional) structural changes resulting from functional alterations. Here, we applied multiphoton imaging, 3D digital reconstructions and computational simulations to generate spatially resolved geometrical and functional models of human liver tissue at different stages of non-alcoholic fatty liver disease (NAFLD). We identified a set of morphometric cellular and tissue parameters correlated with disease progression, and discover profound topological defects in the 3D bile canalicular (BC) network. Personalized biliary fluid dynamic simulations predicted an increased pericentral biliary pressure and micro-cholestasis, consistent with elevated cholestatic biomarkers in patients' sera. Our spatially resolved models of human liver tissue can contribute to high-definition medicine by identifying quantitative multiparametric cellular and tissue signatures to define disease progression and provide new insights into NAFLD pathophysiology.

Liquid-crystal organization of liver tissue.

Functional tissue architecture originates by self-assembly of distinct cell types, following tissue-specific rules of cell-cell interactions. In the liver, a structural model of the lobule was pioneered by Elias in 1949. This model, however, is in contrast with the apparent random 3D arrangement of hepatocytes. Since then, no significant progress has been made to derive the organizing principles of liver tissue. To solve this outstanding problem, we computationally reconstructed 3D tissue geometry from microscopy images of mouse liver tissue and analyzed it applying soft-condensed-matter-physics concepts. Surprisingly, analysis of the spatial organization of cell polarity revealed that hepatocytes are not randomly oriented but follow a long-range liquid-crystal order. This does not depend exclusively on hepatocytes receiving instructive signals by endothelial cells, since silencing Integrin-ß1 disrupted both liquid-crystal order and organization of the sinusoidal network. Our results suggest that bi-directional communication between hepatocytes and sinusoids underlies the self-organization of liver tissue.

Feeding ecomorphologies in the fish genus Herichthys (Perciformes: Cichlidae) based on stomach content and lower pharyngeal jaw shape

Speciation is a multifactorial process with factors acting at different scales of space and time. Trophic niche segregation has promoted the diversification of cichlids fishes in lentic (lacustrine) environments, whether this is also the case in lotic (riverine) systems remains unknown. Herichthys is the genus of cichlids with the most boreal distribution in the Americas comprising 12 currently recognized species, most micro-endemic and only two with a wide distribution. In the present work, we analyzed the stomach content and lower pharyngeal jaw morphologies of the species of the genus to evaluate the possible role of feeding ecology in the diversification of the group. Trophic strategies varied widely, including omnivores, piscivores, invertivores, molluskivores, detritivores, herbivores and algivores. Low values of Pianka's index of niche overlap were found in the sympatric micro-endemic species, while in the widely distributed species the indices ranged from low to very high. The analysis of lower pharyngeal jaw morphologies allowed discriminating a shape associated with piscivorous species from other foraging groups. The results of this study suggest that trophic niche segregation is a factor that could promotes diversification within the genus Herichthys although additional studies need to be performed to fully understand the speciation process in this group of Neotropical cichlid fishes.

La especiación es un proceso con múltiples factores que actúan a diferentes escalas de espacio y tiempo. La segregación de nichos tróficos es un proceso que ha promovido la diversificación en cíclidos en entornos lacustres, pero en el caso de los ríos no está claro. Herichthys es un género de cíclidos cuya distribución es la más boreal en América, el cual comprende 12 especies actualmente reconocidas, la mayoría microendémicas y solo dos con una amplia distribución. En el presente trabajo, se analizó el contenido estomacal y las morfologías de la mandíbula faríngea inferior de las especies del género para compararlas y evaluar su posible papel en la diversificación del grupo. La dieta en dichas especies es muy variada e incluyó tanto especies que pueden ser consideradas omnívoras como especialistas. Se encontraron valores bajos del índice de solapamiento alimentario (índice de Pianka) en las especies simpátricas microendémicas, mientras que en las especies ampliamente distribuidas el índice fue muy variable. El análisis de morfometría geométrica de la mandíbula faríngea inferior permite discriminar dos formas principales, una que incluye la especie piscívora y otra que incluye a los otros grupos alimentarios. Los resultados encontrados en este estudio sugieren que la segregación de nicho trófico es un factor que promueve claramente la diversificación dentro del género Herichthys, aunque se deben realizar estudios adicionales para comprender completamente el proceso de especiación en este grupo de peces neotropicales.

Galectin-8 Favors the Presentation of Surface-Tethered Antigens by Stabilizing the B Cell Immune Synapse.

Complete activation of B cells relies on their capacity to extract tethered antigens from immune synapses by either exerting mechanical forces or promoting their proteolytic degradation through lysosome secretion. Whether antigen extraction can also be tuned by local cues originating from the lymphoid microenvironment has not been investigated. We here show that the expression of Galectin-8-a glycan-binding protein found in the extracellular milieu, which regulates interactions between cells and matrix proteins-is increased within lymph nodes under inflammatory conditions where it enhances B cell arrest phases upon antigen recognition in vivo and promotes synapse formation during BCR recognition of immobilized antigens. Galectin-8 triggers a faster recruitment and secretion of lysosomes toward the B cell-antigen contact site, resulting in efficient extraction of immobilized antigens through a proteolytic mechanism. Thus, extracellular cues can determine how B cells sense and extract tethered antigens and thereby tune B cell responses in vivo.

Content-aware image restoration: pushing the limits of fluorescence microscopy.

Fluorescence microscopy is a key driver of discoveries in the life sciences, with observable phenomena being limited by the optics of the microscope, the chemistry of the fluorophores, and the maximum photon exposure tolerated by the sample. These limits necessitate trade-offs between imaging speed, spatial resolution, light exposure, and imaging depth. In this work we show how content-aware image restoration based on deep learning extends the range of biological phenomena observable by microscopy. We demonstrate on eight concrete examples how microscopy images can be restored even if 60-fold fewer photons are used during acquisition, how near isotropic resolution can be achieved with up to tenfold under-sampling along the axial direction, and how tubular and granular structures smaller than the diffraction limit can be resolved at 20-times-higher frame rates compared to state-of-the-art methods. All developed image restoration methods are freely available as open source software in Python, FIJI, and KNIME.

Características morfométricas de los dientes multirradiculares a nivel de la zona de furcación / RESEARCH Morphometric characteristics of multirooted teeth and furcation area

Objetivo. Describir las características morfométricas de los dientes multirradiculares a nivel de la zona de furcación. Método. 54 dientes multirradiculares (maxilares y mandibulares); fueron evaluados a través de un calibrador de precisión: longitud del tronco radicular, separación radicular, ángulo de divergencia radicular, longitud radicular así como la extensión de las proyecciones cervicales del esmalte y presencia de perlas del esmalte. Resultados. El ángulo de divergencia de la furca distal (50°) maxilar fue mayor que a nivel bucal (22°) y mesial (37°), a nivel mandibular bucal fue de 25° y lingual de 22°. No se encontró perlas del esmalte y las proyecciones cervicales del esmalte más comunes fueron de clase I a nivel bucal (60% para maxilares y 31% para mandibulares). La longitud del tronco radicular lingual fue de 2,8mm y a nivel bucal de 2,2mm. Conclusión. El tronco radicular de los molares mandibulares es mayor a nivel lingual que bucal, al igual que la zona palatina de molares maxilares. En los molares maxilares el mayor ángulo de divergencia se presentó en la entrada de la furca distal, siendo esta la recomendable para iniciar la instrumentación mecánica.

Objective. The aim of this study is to describe the morphometric characteristics of multirooted teeth at the furcation area. Method. Fifty-four multirooted teeth (maxillary and mandibular teeth) were evaluated using a precision calibrator: root trunk length, root separation, root divergence angle, root length, length of cervical enamel projections and presence of enamel pearls. Results. The divergence angle of the maxillary distal furcation (50°) was greater than on the buccal (22°) and mesial (37°) aspects. On the mandible it was 25° on the buccal aspect and 22° lingually. No enamel pearls were found. The cervical enamel projections most commonly found were class I on the oral aspect (60% for maxillary teeth and 31% for mandibular teeth). The length of the lingual root trunk was 2.8 mm, and on the buccal aspect it was 2.2 mm. Conclusion. The root trunk of mandibular molars is larger lingually than on the buccal aspect, as is the palatal area of maxillary molars. In maxillary molars the greater divergence angle appeared at the entrance of the distal furcation, which is the one recommended to start using mechanical instruments.

Galectin-8 as an immunosuppressor in experimental autoimmune encephalomyelitis and a target of human early prognostic antibodies in multiple sclerosis.

Galectin-8 (Gal-8) is a member of a glycan-binding protein family that regulates the immune system, among other functions, and is a target of antibodies in autoimmune disorders. However, its role in multiple sclerosis (MS), an autoimmune inflammatory disease of the central nervous system (CNS), remains unknown. We study the consequences of Gal-8 silencing on lymphocyte subpopulations and the development of experimental autoimmune encephalitis (EAE), to then assess the presence and clinical meaning of anti-Gal-8 antibodies in MS patients. Lgals8/Lac-Z knock-in mice lacking Gal-8 expression have higher polarization toward Th17 cells accompanied with decreased CCR6+ and higher CXCR3+ regulatory T cells (Tregs) frequency. These conditions result in exacerbated MOG35-55 peptide-induced EAE. Gal-8 eliminates activated Th17 but not Th1 cells by apoptosis and ameliorates EAE in C57BL/6 wild-type mice. ß-gal histochemistry reflecting the activity of the Gal-8 promoter revealed Gal-8 expression in a wide range of CNS regions, including high expression in the choroid-plexus. Accordingly, we detected Gal-8 in human cerebrospinal fluid, suggesting a role in the CNS immune-surveillance circuit. In addition, we show that MS patients generate function-blocking anti-Gal-8 antibodies with pathogenic potential. Such antibodies block cell adhesion and Gal-8-induced Th17 apoptosis. Furthermore, circulating anti-Gal-8 antibodies associate with relapsing-remitting MS (RRMS), and not with progressive MS phenotypes, predicting clinical disability at diagnosis within the first year of follow-up. Our results reveal that Gal-8 has an immunosuppressive protective role against autoimmune CNS inflammation, modulating the balance of Th17 and Th1 polarization and their respective Tregs. Such a role can be counteracted during RRMS by anti-Gal-8 antibodies, worsening disease prognosis. Even though anti-Gal-8 antibodies are not specific for MS, our results suggest that they could be a potential early severity biomarker in RRMS.

A Predictive 3D Multi-Scale Model of Biliary Fluid Dynamics in the Liver Lobule.

Bile, the central metabolic product of the liver, is transported by the bile canaliculi network. The impairment of bile flow in cholestatic liver diseases has urged a demand for insights into its regulation. Here, we developed a predictive 3D multi-scale model that simulates fluid dynamic properties successively from the subcellular to the tissue level. The model integrates the structure of the bile canalicular network in the mouse liver lobule, as determined by high-resolution confocal and serial block-face scanning electron microscopy, with measurements of bile transport by intravital microscopy. The combined experiment-theory approach revealed spatial heterogeneities of biliary geometry and hepatocyte transport activity. Based on this, our model predicts gradients of bile velocity and pressure in the liver lobule. Validation of the model predictions by pharmacological inhibition of Rho kinase demonstrated a requirement of canaliculi contractility for bile flow in vivo. Our model can be applied to functionally characterize liver diseases and quantitatively estimate biliary transport upon drug-induced liver injury.

A versatile pipeline for the multi-scale digital reconstruction and quantitative analysis of 3D tissue architecture.

A prerequisite for the systems biology analysis of tissues is an accurate digital three-dimensional reconstruction of tissue structure based on images of markers covering multiple scales. Here, we designed a flexible pipeline for the multi-scale reconstruction and quantitative morphological analysis of tissue architecture from microscopy images. Our pipeline includes newly developed algorithms that address specific challenges of thick dense tissue reconstruction. Our implementation allows for a flexible workflow, scalable to high-throughput analysis and applicable to various mammalian tissues. We applied it to the analysis of liver tissue and extracted quantitative parameters of sinusoids, bile canaliculi and cell shapes, recognizing different liver cell types with high accuracy. Using our platform, we uncovered an unexpected zonation pattern of hepatocytes with different size, nuclei and DNA content, thus revealing new features of liver tissue organization. The pipeline also proved effective to analyse lung and kidney tissue, demonstrating its generality and robustness.

Morphometric variation of the Herichthys bartoni (Bean, 1892) species group (Teleostei: Cichlidae): How many species comprise H. labridens (Pellegrin, 1903)?

Cichlids of the tribe Heroini have long been a source of taxonomical conflict. In particular, the species included in the Herichthys bartoni group have failed to be recovered as monophyletic in different molecular studies. In this paper we use traditional and geometric morphometrics to evaluate morphological variation in the species included in the H. bartoni complex in order to evaluate the number of species it contains. An update of a previously published DNA barcoding study suggests the existence of three genetic clusters that included the six recognized species analyzed in this study, none of them recovered as monophyletic. On the other hand, geometric morphometrics arise as a useful tool to discriminate species due that traditional morphometrics showed a high overlap in the characters analyzed that prevents the proposal of diagnostic characters.

Los cíclidos de la tribu Heroini han experimentado un largo conflicto taxonómico. En particular, las especies incluidas en el grupo Herichthys bartoni no han sido recuperadas como monofiléticas en diversos estudios moleculares. En este artículo nosotros usamos morfometría tradicional y geométrica para evaluar la variación morfológica de las especies incluidas en el complejo H. bartoni para evaluar el numero de especies que contiene. Una actualización de un estudio previo de código de barras de ADN sugiere la existencia de tres grupos genéticos que incluyen las seis especies reconocidas analizadas en este estudio, ninguna de las cuales fue recuperada como monofilética. Por otro lado, la morfometría geométrica surge como una herramienta de utilidad para discriminar especies debido a que la variación en caracteres morfométricos tradicionales muestra altos niveles de solapamiento que previene la propuesta de caracteres diagnósticos.