Microfluidics for Neuronal Cell and Circuit Engineering.

The widespread adoption of microfluidic devices among the neuroscience and neurobiology communities has enabled addressing a broad range of questions at the molecular, cellular, circuit, and system levels. Here, we review biomedical engineering approaches that harness the power of microfluidics for bottom-up generation of neuronal cell types and for the assembly and analysis of neural circuits. Microfluidics-based approaches are instrumental to generate the knowledge necessary for the derivation of diverse neuronal cell types from human pluripotent stem cells, as they enable the isolation and subsequent examination of individual neurons of interest. Moreover, microfluidic devices allow to engineer neural circuits with specific orientations and directionality by providing control over neuronal cell polarity and permitting the isolation of axons in individual microchannels. Similarly, the use of microfluidic chips enables the construction not only of 2D but also of 3D brain, retinal, and peripheral nervous system model circuits. Such brain-on-a-chip and organoid-on-a-chip technologies are promising platforms for studying these organs as they closely recapitulate some aspects of in vivo biological processes. Microfluidic 3D neuronal models, together with 2D in vitro systems, are widely used in many applications ranging from drug development and toxicology studies to neurological disease modeling and personalized medicine. Altogether, microfluidics provide researchers with powerful systems that complement and partially replace animal models.

Medical management of small uterocutaneous fistulae with gonadotrophin releasing hormone analogs: Case report and literature review.

Conventional management of uterocutaneous fistula involves open or laparoscopic excision as well as hysterectomy but there is now increasing recognition of successful medical treatment with gonadotrophin releasing hormone agonists. We describe the fourth case in the literature of successful nonsurgical treatment of uterocutaneous fistula and discuss two important factors affect the success of medical management, namely the size of the fistula and the duration of treatment. We would recommend that a trial of gonadotrophin releasing hormone analogues for at least 6 months particularly in cases of uterocutaneous fistula of 5 mm or less in diameter as this conservative treatment is likely to obviate the need for more hazardous surgical intervention.

VEGF-Trap is a potent modulator of vasoregenerative responses and protects dopaminergic amacrine network integrity in degenerative ischemic neovascular retinopathy.

Retinal hypoxia triggers abnormal vessel growth and microvascular hyper-permeability in ischemic retinopathies. Whereas vascular endothelial growth factor A (VEGF-A) inhibitors significantly hinder disease progression, their benefits to retinal neurons remain poorly understood. Similar to humans, oxygen-induced retinopathy (OIR) mice exhibit severe retinal microvascular malformations and profound neuronal dysfunction. OIR mice are thus a phenocopy of human retinopathy of prematurity, and a proxy for investigating advanced stages of proliferative diabetic retinopathy. Hence, the OIR model offers an excellent platform for assessing morpho-functional responses of the ischemic retina to anti-angiogenic therapies. Using this model, we investigated the retinal responses to VEGF-Trap (Aflibercept), an anti-angiogenic agent recognizing ligands of VEGF receptors 1 and 2 that possesses regulatory approval for the treatment of neovascular age-related macular degeneration, macular edema secondary to retinal vein occlusion and diabetic macular edema. Our results indicate that Aflibercept not only reduces the severity of retinal microvascular aberrations but also significantly improves neuroretinal function. Aflibercept administration significantly enhanced light-responsiveness, as revealed by electroretinographic examinations, and led to increased numbers of dopaminergic amacrine cells. Additionally, retinal transcriptional profiling revealed the concerted regulation of both angiogenic and neuronal targets, including transcripts encoding subunits of transmitter receptors relevant to amacrine cell function. Thus, Aflibercept represents a promising therapeutic alternative for the treatment of further progressive ischemic retinal neurovasculopathies beyond the set of disease conditions for which it has regulatory approval. Cover Image for this issue: doi: 10.1111/jnc.14743.

Association of brain arterial diameters with demographic and anatomical factors in a multi-national pooled analysis of cohort studies.

BACKGROUND AND PURPOSE: Brain arterial diameters are markers of cerebrovascular disease. Demographic and anatomical factors may influence arterial diameters. We hypothesize that age, sex, height, total cranial volume (TCV), and persistent fetal posterior cerebral artery (fPCA) correlate with brain arterial diameters across populations. METHODS: Participants had a time-of-flight MRA from nine international cohorts. Arterial diameters of the cavernous internal carotid arteries (ICA), middle cerebral arteries (MCA), and basilar artery (BA) were measured using LAVA software. Regression models assessed the association between exposures and brain arterial diameters. RESULTS: We included 6,518 participants (mean age: 70 ± 9 years; 41% men). Unilateral fPCA was present in 13.2% and bilateral in 3.2%. Larger ICA, MCA, and BA diameters correlated with older age (Weighted average [WA] per 10 years: 0.18 mm, 0.11 mm, and 0.12 mm), male sex (WA: 0.24 mm, 0.13 mm, and 0.21 mm), and TCV (WA: for one TCV standard deviation: 0.24 mm, 0.29 mm, and 0.18 mm). Unilateral and bilateral fPCAs showed a positive correlation with ICA diameters (WA: 0.39 mm and 0.73 mm) and negative correlation with BA diameters (WA: -0.88 mm and -1.73 mm). Regression models including age, sex, TCV, and fPCA explained on average 15%, 13%, and 25% of the ICA, MCA, and BA diameter interindividual variation, respectively. Using height instead of TCV as a surrogate of head size decreased the R-squared by 3% on average. CONCLUSION: Brain arterial diameters correlated with age, sex, TCV, and fPCA. These factors should be considered when defining abnormal diameter cutoffs across populations.

Identification of novel mutation in cathepsin C gene causing Papillon-Lefèvre Syndrome in Mexican patients.

BACKGROUND: Papillon-Lefèvre Syndrome (PLS) is a type IV genodermatosis caused by mutations in cathepsin C (CTSC), with a worldwide prevalence of 1-4 cases per million in the general population. In México, the prevalence of this syndrome is unknown, and there are few case reports. The diagnosis of twenty patients in the state of Sinaloa highlights the need to characterize this syndrome in Mexicans. METHODS: To understand the basis of PLS in Mexicans, the gene expression, enzymatic activity and mutational analysis of CTSC were assayed in nine PLS patients and their relatives. Frequencies of CTSC gene polymorphisms and HLA alleles were determined in these patients, their relatives, and the population. RESULTS: Patients showed normal CTSC gene expression, but a deep reduction (up to 85%) in enzymatic activity in comparison to unrelated healthy individuals. A novel loss-of-function mutation, c.203 T > G (p.Leu68Arg), was found in all patients, and some carried the polymorphism c.458C > T (p.Thr153Ile). Allelic frequencies in patients, relatives and controls were 88.89%, 38.24% and 0.25% for G (c.203 T > G); and 11.11%, 8.82% and 9.00% for T (c.458C > T). HLA-DRB1*11 was found significantly more frequent (P = 0.0071) in patients than controls (33.33% vs. 7.32%), with an estimated relative risk of 6.33. CONCLUSIONS: The novel loss-of function mutation of CTSC gene (c.203 T > G) found in patients correlated with their diminished enzymatic activity, and HLA-DRB1*11 was found to be associated with PLS. The study of more PLS patients may give more insights into the etiology of the disease as well as its prevalence in México.

Structural Model of Biomedical and Contextual Factors Predicting In-Hospital Mortality due to Heart Failure.

Background: Among the clinical predictors of a heart failure (HF) prognosis, different personal factors have been established in previous research, mainly age, gender, anemia, renal insufficiency and diabetes, as well as mediators (pulmonary embolism, hypertension, chronic obstructive pulmonary disease (COPD), arrhythmias and dyslipidemia). We do not know the role played by contextual and individual factors in the prediction of in-hospital mortality. Methods: The present study has added hospital and management factors (year, type of hospital, length of stay, number of diagnoses and procedures, and readmissions) in predicting exitus to establish a structural predictive model. The project was approved by the Ethics Committee of the province of Almeria. Results: A total of 529,606 subjects participated, through databases of the Spanish National Health System. A predictive model was constructed using correlation analysis (SPSS 24.0) and structural equation models (SEM) analysis (AMOS 20.0) that met the appropriate statistical values (chi-square, usually fit indices and the root-mean-square error approximation) which met the criteria of statistical significance. Individual factors, such as age, gender and chronic obstructive pulmonary disease, were found to positively predict mortality risk. Isolated contextual factors (hospitals with a greater number of beds, especially, and also the number of procedures performed, which negatively predicted the risk of death. Conclusions: It was, therefore, possible to introduce contextual variables to explain the behavior of mortality in patients with HF. The size or level of large hospital complexes, as well as procedural effort, are key contextual variables in estimating the risk of mortality in HF.

VEGF-Trap Modulates Retinal Inflammation in the Murine Oxygen-Induced Retinopathy (OIR) Model.

Anti-Vascular Endothelial Growth Factor (VEGF) agents are the first-line treatment for retinal neovascular diseases, which represent the most prevalent causes of acquired vision loss world-wide. VEGF-Trap (Aflibercept, AFL), a recombinant decoy receptor recognizing ligands of both VEGFR-1 and -2, was recently reported to be highly efficient in improving visual acuity and preserving retinal anatomy in individuals affected by diabetic macular edema. However, the precise molecular and cell biological mechanisms underlying the beneficial effects of this novel tool have yet to be elucidated. Using the mouse oxygen-induced retinopathy (OIR) model as a surrogate of retinopathies with sterile post-ischemic inflammation, such as late proliferative diabetic retinopathy (PDR), retinopathy of prematurity (ROP), and diabetic macular edema (DME), we provide evidence that AFL modulates inflammation in response to hypoxia by regulating the morphology of microglial cells, a parameter commonly used as a proxy for changes in their activation state. We show that AFL administration during the hypoxic period of OIR leads to an increased number of ramified Iba1+ microglial cells/macrophages while subsequently limiting the accumulation of these cells in particular retinal layers. Our results suggest that, beyond its well-documented beneficial effects on microvascular regeneration, AFL might exert important modulatory effects on post-ischemic retinal inflammation.

A Path Analysis Model of Self- vs. Educational-Context- Regulation as Combined Predictors of Well-Being in Spanish College Students.

Previous literature has established the importance of personal and contextual factors in college students' trajectories. Following the Self- vs. External-Regulation Behavior Theory (2021) and the 3P Biggs Model, the present study aimed at analyzing a structural linear model that validates the joint effect of self-regulation, educational context, age, and gender (as personal and contextual presage variables) with other meta-abilities, such as coping strategies, resilience, and positivity (process variables), and specific well-being outcomes, such as flourishing and health (product variables). A sample of 1310 Spanish college students was analyzed, aged 17 to 25, and a cross-sectional study with an ex post facto design was performed. Association and structural equation modeling (SEM) was performed using SPSS software (v.26) and AMOS (v.23). Results show that individual and contextual factors have an important role in the acquisition of psychological competencies in young adults. Self-regulation was proven to be an important meta-ability that predicts personal well-being and behavioral health outcomes. Complementarily, educational context was shown to be an external predictor of other skills, such as problem-focused strategies, and positive outcomes such as flourishing and behavioral health. Practical implications and limitations are discussed.

Validation of the Child and Youth Resilience Measure-28 (CYRM-28) among Spanish youth.

Objectives: This article presents a validation study of the 28-item Child and Youth Resilience Measure (CYRM-28). The sample contained 365 Spanish youth ages between 15 to 21, from Navarre (Spain), all of them enrolled in Initial Vocational Qualification Programs. Method: The CYRM-28 was administered to students from 27 secondary schools in the province of Navarre. Confirmatory analyses were conducted. Results: The structure of the original scale was confirmed, as well as acceptable psychometric properties. Discussion: Findings add support to the CYRM-28 as a reliable and valid self-report instrument that measures three components of resilience processes in the lives of youth with complex needs. The CYRM-28 shows adequate psychometric properties, the CFA presents indices of goodness and fit (Chi-squared = 60,170, df = 17, p < .001; CFI = .960, TLI = .934, IFI = .961, RFI = .911 and NFI = .946; RMSEA = .084). Conclusion: Advanced statistical modeling yielded evidence that the scale, originally developed for use in several countries, can be used to assess resilience in Spanish youth.

Gene expression profile of the murine ischemic retina and its response to Aflibercept (VEGF-Trap).

Ischemic retinal dystrophies are leading causes of acquired vision loss. Although the dysregulated expression of the hypoxia-responsive VEGF-A is a major driver of ischemic retinopathies, implication of additional VEGF-family members in their pathogenesis has led to the development of multivalent anti-angiogenic tools. Designed as a decoy receptor for all ligands of VEGFR1 and VEGFR2, Aflibercept is a potent anti-angiogenic agent. Notwithstanding, the molecular mechanisms mediating Aflibercept's efficacy remain only partially understood. Here, we used the oxygen-induced retinopathy (OIR) mouse as a model system of pathological retinal vascularization to investigate the transcriptional response of the murine retina to hypoxia and of the OIR retina to Aflibercept. While OIR severely impaired transcriptional changes normally ensuing during retinal development, analysis of gene expression patterns hinted at alterations in leukocyte recruitment during the recovery phase of the OIR protocol. Moreover, the levels of Angiopoietin-2, a major player in the progression of diabetic retinopathy, were elevated in OIR tissues and consistently downregulated by Aflibercept. Notably, GO term, KEGG pathway enrichment, and expression dynamics analyses revealed that, beyond regulating angiogenic processes, Aflibercept also modulated inflammation and supported synaptic transmission. Altogether, our findings delineate novel mechanisms potentially underlying Aflibercept's efficacy against ischemic retinopathies.

Automated methods for cell type annotation on scRNA-seq data.

The advent of single-cell sequencing started a new era of transcriptomic and genomic research, advancing our knowledge of the cellular heterogeneity and dynamics. Cell type annotation is a crucial step in analyzing single-cell RNA sequencing data, yet manual annotation is time-consuming and partially subjective. As an alternative, tools have been developed for automatic cell type identification. Different strategies have emerged to ultimately associate gene expression profiles of single cells with a cell type either by using curated marker gene databases, correlating reference expression data, or transferring labels by supervised classification. In this review, we present an overview of the available tools and the underlying approaches to perform automated cell type annotations on scRNA-seq data.

A comprehensive library of human transcription factors for cell fate engineering.

Human pluripotent stem cells (hPSCs) offer an unprecedented opportunity to model diverse cell types and tissues. To enable systematic exploration of the programming landscape mediated by transcription factors (TFs), we present the Human TFome, a comprehensive library containing 1,564 TF genes and 1,732 TF splice isoforms. By screening the library in three hPSC lines, we discovered 290 TFs, including 241 that were previously unreported, that induce differentiation in 4 days without alteration of external soluble or biomechanical cues. We used four of the hits to program hPSCs into neurons, fibroblasts, oligodendrocytes and vascular endothelial-like cells that have molecular and functional similarity to primary cells. Our cell-autonomous approach enabled parallel programming of hPSCs into multiple cell types simultaneously. We also demonstrated orthogonal programming by including oligodendrocyte-inducible hPSCs with unmodified hPSCs to generate cerebral organoids, which expedited in situ myelination. Large-scale combinatorial screening of the Human TFome will complement other strategies for cell engineering based on developmental biology and computational systems biology.

Clinical significance of occult cerebrospinal fluid involvement assessed by flow cytometry in non-Hodgkin's lymphoma patients at high risk of central nervous system disease in the rituximab era.

BACKGROUND AND AIM: Flow cytometry (FCM) analysis of cerebrospinal fluid (CSF) is more sensitive than conventional cytology (CC) for diagnosis of lymphomatous meningeosis, but the clinical significance of occult central nervous system (CNS) disease (positive FCM with negative CC) remains unknown. PATIENTS AND METHODS: CSF samples from 105 patients with newly diagnosed aggressive lymphomas at high risk of CNS involvement were prospectively studied by both CC and FCM, and results were correlated with cumulative incidence of CNS relapse and overall survival (OS). Patients were divided into three groups: 1) patients without CNS involvement (CC-/FCM-; n=83); 2) individuals with occult CNS disease (FCM+/CC-; n=15); and 3) cases with CNS disease (CC+/FCM+; n=7). RESULTS: Six cases showed CNS relapse or progression: two in Group 1 (2.4%), two in Group 2 (13%) and two in Group 3 (28.5%) (Group 2 vs. 1, P=0.04; Group 3 vs. 1, P<0.001). Patients from Groups 2 (P=0.05) and 3 (P<0.001) also showed a higher cumulative incidence of CNS relapse than those from Group 1. Significant differences were observed in OS between FCM-/CC- and FCM+/CC+ cases (P=0.02), while patients with occult CNS disease (FCM+/CC-) displayed intermediate OS rates, although differences did not reach statistical significance. CONCLUSIONS: The presence of occult CNS involvement at diagnosis in patients with NHL at high risk of CNS disease is associated with a higher probability of CNS relapse.

Assessing self-regulated learning in early childhood education: Difficulties, needs, and prospects.

Self-regulated learning is one of the main processes being investigated today within developmental and educational psychology; however, the research has come up against a number of challenges for which no satisfactory response has been found, and which are impeding progress in the field. These challenges are two-fold: one part is methodological, as the process of self-regulation must be evaluated at the very moment in which it occurs, and the other part is developmental, as these processes have not been fully assessed in children under the age of 6 years. This article gives a broad overview of these challenges, as well as prospects for future solutions which are beginning to take shape.

[Perception of the teaching-learning process and academic achievement in diverse instructional contexts of Higher Education]. / Percepción del proceso de enseñanza-aprendizaje y rendimiento académico en diferentes contextos instruccionales de la Educación Superior.

In Higher Education, performance and Teaching-Learning (T-L) contexts are highly current concerns. Based on the DEDEPRO model, interdependence can be established between instructional contexts and levels of performance as they relate to the T-L process. Partitipants were 2020 pupils from two Spanish universities. Measurements of both variables were used in a quasi-experimental and correlational design. The univariate and causal analyses showed the effect of context on the T-L process and on performance; thus, the interdependent relationships between the latter and perception of the T-L process. Partial interaction effects also appeared, as well as a causal model of academic performance. Results are discussed and implications for the ECTS (European Credit Transfer System) are analyzed.

Costochondral graft with green-stick fracture used in reconstruction of the mandibular condyle: experience in 13 clinical cases.

Since its publication in 1920 by Gillies, costochondral grafts have been used by surgeons to replace and injured mandibular condyle and to reconstruct the temporomandibular joint. This procedure is currently applied in cases of congenital dysplasia, developmental defects, temporomandibular ankylosis, neoplastic disease, osteoarthritis and post-traumatic dysfunction. Over the years, various procedures for the reconstruction with this type of graft have been described. In 1989, Mosby and Hiatt described a technique for setting the graft securely, reducing the space between the graft and the mandibular area. In 1998, Monje and Martín-Granizo developed a variation of this method, enabling a precise adaptation of the costochondral graft to the remaining mandibular ramus. The aim of this study is to evaluate the functional and anatomic results of the costochondral graft treatment by green-stick fracture for reconstruction of the TMJ in the 10 years following the description of this technique. We carry out a retrospective study of thirteen cases of temporomandibular pathology (tumors, ankylosis and hypoplasia) treated during a period of ten years from 1998 to 2008. In all these cases, the technique described by Monje and Martín-Granizo was used: removal of the sixth rib, fixation to a titanium mini-plate using screws, making an internal corticotomy in order to obtain a green-stick fracture of the outer cortex, providing adequate adaptation of the graft to the mandibular ramus. The graft was then set in place, attaching it with titanium screws. This technique was successful in achieving optimal ossification, a good interincisal opening and satisfactory cosmetic results. In conclusion, according to our experience, the green-stick fracture for the adaptation of costochondral grafts to the remaining mandibular ramus has presented outstanding results in the surgical treatment of temporomandibular pathology.

Metastasis of renal clear-cell carcinoma to the oral mucosa, an atypical location.

The majority of cases of metastatic tumors involve the mandible and some the maxilla but they are considerably less common in intraoral soft tissues. In addition, the primary tumor is known in the majority of cases; although in one-third of such cases, metastasis is the first clinical manifestation. The most common primary tumors metastasizing to the mouth are lung carcinoma in men and breast carcinoma in women. An oral metastasis implies a serious prognosis, as in the majority of patients there is multiple organ involvement at the time of diagnosis. We present the case of a 52-year old patient with renal pathology who came to the emergency room due to a rapidly increasing gingival tumor. With the provisional clinical diagnosis of a pyogenic granuloma,the tumor was excised. Subsequent anatomopathological analysis revealed a tumor metastasis compatible with clear-cell carcinoma, and its renal origin was confirmed by means of immunohistochemical techniques.

[Personal self-regulation and perceived maladjusted school behaviors]. / Autorregulación personal y percepción de los comportamientos escolares desadaptativos.

The purpose of this study is to confirm the extent to which subjects' ability to self-regulate, during mid-adolescence, influences their perception of maladjustment problems. The sample comprised 888 adolescents between 12 and 17 years of age. The study followed an inferential methodology, using two instruments, a Spanish version of the Personal Self-regulation Questionnaire (2003, 2007) and the Cuestionario de Problemas de Desadaptación Escolar [Questionnaire for the Assessment of School Maladjustment Problems] (2007) to measure the variables of interest. Results from the inferential analyses (ANOVAS) suggest that the degree of personal self-regulation is interdependent with respect to perceived maladjustment and relational problems at school. Results and implications for future research are discussed.

Challenges in microRNAs' targetome prediction and validation.

MicroRNAs (miRNAs) are small RNA molecules with important roles in post-transcriptional regulation of gene expression. In recent years, the predicted number of miRNAs has skyrocketed, largely as a consequence of high-throughput sequencing technologies becoming ubiquitous. This dramatic increase in miRNA candidates poses multiple challenges in terms of data deposition, curation, and validation. Although multiple databases containing miRNA annotations and targets have been developed, ensuring data quality by validating miRNA-target interactions requires the efforts of the research community. In order to generate databases containing biologically active miRNAs, it is imperative to overcome a multitude of hurdles, including restricted miRNA expression patterns, distinct miRNA biogenesis machineries, and divergent miRNA-mRNA interaction dynamics. In the present review, we discuss recent advances and limitations in miRNA prediction, identification, and validation. Lastly, we focus on the most enriched neuronal miRNA, miR-124, and its gene regulatory network in human neurons, which has been revealed using a combined computational and experimental approach.

Retinal miRNA Functions in Health and Disease.

The health and function of our visual system relies on accurate gene expression. While many genetic mutations are associated with visual impairment and blindness, we are just beginning to understand the complex interplay between gene regulation and retinal pathologies. MicroRNAs (miRNAs), a class of non-coding RNAs, are important regulators of gene expression that exert their function through post-transcriptional silencing of complementary mRNA targets. According to recent transcriptomic analyses, certain miRNA species are expressed in all retinal cell types, while others are cell type-specific. As miRNAs play important roles in homeostasis, cellular function, and survival of differentiated retinal cell types, their dysregulation is associated with retinal degenerative diseases. Thus, advancing our understanding of the genetic networks modulated by miRNAs is central to harnessing their potential as therapeutic agents to overcome visual impairment. In this review, we summarize the role of distinct miRNAs in specific retinal cell types, the current knowledge on their implication in inherited retinal disorders, and their potential as therapeutic agents.