RESUMEN
Current knowledge of the evolution of the postcranial skeleton in the genus Homo is hampered by a geographically and chronologically scattered fossil record. Here we present a complete characterization of the postcranium of the middle Pleistocene paleodeme from the Sima de los Huesos (SH) and its paleobiological implications. The SH hominins show the following: (i) wide bodies, a plesiomorphic character in the genus Homo inherited from their early hominin ancestors; (ii) statures that can be found in modern human middle-latitude populations that first appeared 1.6-1.5 Mya; and (iii) large femoral heads in some individuals, a trait that first appeared during the middle Pleistocene in Africa and Europe. The intrapopulational size variation in SH shows that the level of dimorphism was similar to modern humans (MH), but the SH hominins were less encephalized than Neandertals. SH shares many postcranial anatomical features with Neandertals. Although most of these features appear to be either plesiomorphic retentions or are of uncertain phylogenetic polarity, a few represent Neandertal apomorphies. Nevertheless, the full suite of Neandertal-derived features is not yet present in the SH population. The postcranial evidence is consistent with the hypothesis based on the cranial morphology that the SH hominins are a sister group to the later Neandertals. Comparison of the SH postcranial skeleton to other hominins suggests that the evolution of the postcranium occurred in a mosaic mode, both at a general and at a detailed level.
Asunto(s)
Fósiles , Cráneo/anatomía & histología , Animales , Estatura , Tamaño Corporal , Huesos/anatomía & histología , Hominidae/anatomía & histología , Humanos , Hombre de Neandertal/anatomía & histología , Paleontología , Filogenia , Dinámica Poblacional , EspañaRESUMEN
Dry eye disease is one of the most frequent pathological events that take place in the course of the graft versus host disease (GVHD), and is the main cause of deterioration in quality of life for patients. Thus, demonstration of dry eye signs in murine models of oGVHD is crucial for the validation of these models for the study of the disease. Given the increasing evidence that tear osmolarity is an important player of dry eye disease, our purpose in this study was to validate the use of a reliable method to assess tear osmolarity in mice: the electrical impedance method. Then, we wanted to test its utility with an oGVHD model. Tear volume assessment was also performed, using the phenol red thread test. We found differences in tear osmolarity in mice that received a transplant with cells from bone marrow and spleen (the GVHD group) when compared with mice that only received bone marrow cells (the BM group) at day 7 (362 ± 8 mOsm/l and 345 ± 9 mOsm/l respectively; P < 0.01) and day 21 (348 ± 19 mOsm/l vs. 326 ± 15 mOsm/l; P < 0.05). We found also differences in tear volume at day 14 (2.30 ± 0.61 mm in oGVHD group and 2.89 ± 0.62 mm in BM group; P = 0.06) and at day 21 (2.10 ± 0.30 mm in oGVHD group and 2.89 ± 0.32 mm in BM group; P < 0.01). Besides this, we observed reduction in epithelial thickness between the GVHD and BM groups (37.0 ± 6.2 µm and 43.6 ± 3.3 µm respectively; P < 0.05). These data show the usefulness of the electrical impedance method to measure tear osmolarity in mice. We can also conclude that this oGVHD model mimics the tear film alterations found in human dry eye disease, what contributes to give relevance to this model for the study of GVHD.
Asunto(s)
Síndromes de Ojo Seco/diagnóstico , Epitelio Corneal/metabolismo , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Lágrimas/metabolismo , Animales , Modelos Animales de Enfermedad , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/metabolismo , Epitelio Corneal/patología , Enfermedad Injerto contra Huésped/complicaciones , Enfermedad Injerto contra Huésped/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Concentración OsmolarRESUMEN
Oligodendrocytes are the myelinating cells in the central nervous system. In birds and mammals, the oligodendrocyte progenitor cells (OPCs) originate in the preoptic area (POA) of the hypothalamus. However, it remains unclear in other vertebrates such as fish. Thus, we have studied the early progression of OPCs during zebrafish visual morphogenesis from 2 days post fertilization (dpf) until 11 dpf using the olig2:EGFP transgenic line; and we have analyzed the differential expression of transcription factors involved in oligodendrocyte differentiation: Sox2 (using immunohistochemistry) and Sox10 (using the transgenic line sox10:tagRFP). The first OPCs (olig2:EGFP/Sox2) were found at 2 dpf in the POA. From 3 dpf onwards, these olig2:EGFP/Sox2 cells migrate to the optic chiasm, where they invade the optic nerve (ON), extending toward the retina. At 5 dpf, olig2:EGFP/Sox2 cells in the ON also colocalize with sox10:tagRFP. When olig2:EGFP cells differentiate and present more projections, they become positive only for sox10:tagRFP. olig2:EGFP/sox10: tagRFP cells ensheath the ON by 5 dpf when they also become positive for a myelin marker, based on the mbpa:tagRFPt transgenic line. We also found olig2:EGFP cells in other regions of the visual system. In the central retina at 2 dpf, they are positive for Sox2 but later become restricted to the proliferative germinal zone without this marker. In the ventricular areas of the optic tectum, olig2:EGFP cells present Sox2 but arborized ones sox10:tagRFP instead. Our data matches with other models, where OPCs are specified in the POA and migrate to the ON through the optic chiasm.
Asunto(s)
Oligodendroglía , Pez Cebra , Animales , Pez Cebra/metabolismo , Diferenciación Celular/fisiología , Factor de Transcripción 2 de los Oligodendrocitos/metabolismo , Oligodendroglía/metabolismo , Animales Modificados Genéticamente , Vaina de Mielina/fisiología , Factores de Transcripción SOXE/genética , Factores de Transcripción SOXE/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , MamíferosRESUMEN
Zebrafish (Danio rerio) present continuous growth and regenerate many parts of their body after an injury. Fish oligodendrocytes, microglia and astrocytes support the formation of new connections producing effective regeneration of the central nervous system after a lesion. To understand the role of oligodendrocytes and the signals that mediate regeneration, we use the well-established optic nerve (ON) crush model. We also used sox10 fluorescent transgenic lines to label fully differentiated oligodendrocytes. To quench the effect of reactive oxygen species (ROS), we used the endogenous antioxidant melatonin. Using these tools, we measured ROS production by flow cytometry and explored the regeneration of the optic tectum (OT), the response of oligodendrocytes and their mitochondria by confocal microscopy and Western blot. ROS are produced by oligodendrocytes 3 h after injury and JNK activity is triggered. Concomitantly, there is a decrease in the number of fully differentiated oligodendrocytes in the OT and in their mitochondrial population. By 24 h, oligodendrocytes partially recover. Exposure to melatonin blocks the changes observed in these oligodendrocytes at 3 h and increases their number and their mitochondrial populations after 24 h. Melatonin also blocks JNK upregulation and induces aberrant neuronal differentiation in the OT. In conclusion, a proper balance of ROS is necessary during visual system regeneration and exposure to melatonin has a detrimental impact.
RESUMEN
OBJECTIVES: To evaluate the impact of a quality-of-care improvement program implemented in emergency departments (EDs) in a Spanish autonomous community with the aim of reducing the use of unrecommended drugs when treating infants for acute bronchiolitis. MATERIAL AND METHODS: Before-after quasi-experimental intervention study. We retrospectively included infants aged 12 months or less who were treated for acute bronchiolitis in 24 Spanish national health system hospital EDs in December during 2 epidemic periods: in 2018, before implementing the program, and in 2019, after implementation. Data collected included epidemiologic information, clinical and care details, and clinical course. The program consisted of providing informative material and training sessions before the epidemic period started. RESULTS: A total of 7717 episodes (4007 in 2018 and 2710 in 2019) were identified. Epidemiologic and clinical characteristics did not differ between the 2 periods. ED use of the following treatments decreased between the 2 periods: salbutamol, from 29.4% (95% CI, 28.8%-30.8%) in 2018 to 10.6% (95% CI, 9.6%-11.6%) in 2019; epinephrine from 6.0% (95% CI, 5.3%-6.8%) to 0.9% (95% CI, 0.7%-1.3%); and hypertonic saline solution fell from 8.2% (95% CI, 7.3%-9.1%) to 2.1% (95% CI, 1.7%-2.6%) (P.001, all comparisons). Prescriptions for salbutamol on discharge fell from 38.7% (95% CI, 36.9%-40.4%) to 10.6% (95% CI, 9.6%-11.6%) (P.001). Admissions and readmissions did not change, and the median time (interquartile range) spent in the ED fell from 81 (44-138) minutes to 66 (37-127) minutes (P.001). CONCLUSION: The quality-of-care improvement initiative was able to decrease the number of unrecommended therapeutic interventions for acute bronchiolitis. However, we identified great variations between EDs, suggesting that training and assessment of impact should continue.
OBJETIVO: Evaluar el impacto de una iniciativa de mejora realizada en los servicios de urgencias (SU) de una comunidad autónoma para reducir el uso de fármacos no recomendados en lactantes con bronquiolitis aguda (BA). METODO: Estudio cuasi-experimental analítico del tipo "antes y después de una intervención". Se incluyeron de forma retrospectiva todas las BA en niños # 12 meses atendidas en los SU de 24 hospitales públicos durante el mes de diciembre de dos periodos epidémicos: 2018 (preintervención) y 2019 (postintervención). Se recogieron variables epidemiológicas, clínicas, asistenciales y evolutivas. La intervención consistió en difundir material informativo y realizar actividades formativas previas al periodo epidémico. RESULTADOS: Se incluyeron 7.717 episodios (2018: 4.007 y 2019: 3.710). No existieron diferencias en las características epidemiológicas y clínicas. El empleo de salbutamol en los SU descendió del 29,4% [intervalo de confianza del 95% (IC 95%): 28,8-30,8] en 2018 al 10,6% (IC 95%: 9,6-11,6) en 2019 (p 0,001), el de adrenalina del 6,0% (IC 95%: 5,3-6,8) al 0,9% (IC 95%: 0,7-1,3) y el de suero salino hipertónico del 8,2% (IC 95%: 7,3-9,1) al 2,1% (IC 95%: 1,7-2,6) (p 0,001). La prescripción al alta de salbutamol se redujo del 38,7% (IC 95%: 36,9-40,4) al 10,6% (IC 95%: 9,6-11,6) (p 0,001). La tasa de ingreso y la tasa de readmisión no cambiaron y la mediana de tiempo de estancia en los SU se redujo 81 minutos [rango intercuartil (RIC) 44-138] a 66 (RIQ: 37-127) (p 0,001). CONCLUSIONES: La iniciativa de mejora ha conseguido disminuir la tasa de intervenciones terapéuticas no indicadas en BA. Sin embargo, existe una gran variabilidad entre los diferentes SU por lo que la estrategia y la medición de su impacto deben mantenerse en el tiempo.
Asunto(s)
Bronquiolitis , Humanos , Lactante , Estudios Retrospectivos , Enfermedad Aguda , Bronquiolitis/tratamiento farmacológico , Servicio de Urgencia en Hospital , Albuterol/uso terapéuticoRESUMEN
Apicobasal polarity is a hallmark of retinal pigment epithelium cells and is required to perform their functions; however, the precise roles of the different proteins that execute polarity are still poorly understood. Here, we have studied the expression and location of Scribble, the core member of the polarity basal protein complex in epithelial-derived cells, in human and mouse RPE cells in both control and pathological conditions. We found that Scribble specifically localizes at the basolateral membrane of mouse and human RPE cells. In addition, we observed an increase in the expression of Scribble during human RPE development in culture, while it acquires a well-defined basolateral pattern as this process is completed. Finally, the expression and location of Scribble were analyzed in human RPE cells in experimental conditions that mimic the toxic environment suffered by these cells during AMD development and found an increase in Scribble expression in cells that develop a pathological phenotype, suggesting that the protein could be altered in cells under stress conditions, as occurs in AMD. Together, our results demonstrate, for the first time, that Scribble is expressed in both human and mouse RPE and is localized at the basolateral membrane in mature cells. Furthermore, Scribble shows impaired expression and location in RPE cells in pathological conditions, suggesting a possible role for this protein in the development of pathologies, such as AMD.
RESUMEN
Doublecortin (DCX) is a microtubule associated protein, essential for correct central nervous system development and lamination in the mammalian cortex. It has been demonstrated to be expressed in developing-but not in mature-neurons. The teleost visual system is an ideal model to study mechanisms of adult neurogenesis due to its continuous life-long growth. Here, we report immunohistochemical, in silico, and western blot analysis to detect the DCX protein in the visual system of teleost fish. We clearly determined the expression of DCX in newly generated cells in the retina of the cichlid fish Astatotilapia burtoni, but not in the cyprinid fish Danio rerio. Here, we show that DCX is not associated with migrating cells but could be related to axonal growth. This work brings to light the high conservation of DCX sequences between different evolutionary groups, which make it an ideal marker for maturing neurons in various species. The results from different techniques corroborate the absence of DCX expression in zebrafish. In A. burtoni, DCX is very useful for identifying new neurons in the transition zone of the retina. In addition, this marker can be applied to follow axons from maturing neurons through the neural fiber layer, optic nerve head, and optic nerve.
RESUMEN
INTRODUCTION: Resistance to antibiotics is a growing problem with repercussions on the choice of first-line treatment in urinary tract infection (UTI) in childhood. OBJECTIVES: To know the current pattern of antibiotic susceptibility/resistance of the most frequent germs that cause UTI in our healthcare area. Secondary objective is to know the evolution of these patterns over time. PATIENTS AND METHODS: A cross-sectional retrospective study of UTI episodes in a first-level hospital in two periods: 1st January 2008-31th December 2010 and 1st January 2017-31th December 2019 through a review of medical records, recording the following variables: Age, sex, fever, hospital admission, uropathy/bladder dysfunction, antibiotic prophylaxis. RESULTS: First period: 174 UTI episodes (156 patients); Second period: 266 UTI episodes (218 patients). The most frequently isolated germ was E. coli, but in patients with uropathy or bladder dysfunction, the percentage of different germs is greater. A significant increase in resistance to amoxicillin/clavulanate (from 12.2 to 24%) is observed between both periods, it remains stable and in an acceptable range for gentamicin, cotrimoxazole and slightly increases to first-generation cephalosporins. In patients with uropathy/bladder dysfunction, resistance to all these antibiotics is significantly increased. CONCLUSIONS: The increased resistance of the most frequent uropathogens in the UTI of the pediatric population of our healthcare area to amoxicillin/clavulanate makes it unsuitable as empirical therapy. First-generation cephalosporins are an adequate alternative in patients without risk factors.
Asunto(s)
Pediatría , Infecciones Urinarias , Niño , Humanos , Escherichia coli , Estudios Transversales , Estudios Retrospectivos , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/etiología , Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Antibacterianos/uso terapéutico , Cefalosporinas/uso terapéutico , Hospitales , Farmacorresistencia BacterianaRESUMEN
In this work, we used the pcd (Purkinje cell degeneration) mutant mouse with a slow temporal progression of photoreceptor degeneration in order to analyze the structural and functional modifications in the neuronal populations of the outer and inner retina. Retinal immunocytochemistry and functional electroretinography were performed on the pcd/pcd mutant mice and control wild type animals of the C57/DBA strain at 45, 90, 180 and 270 post-natal days. Immunohistochemical studies were performed for a series of protein markers: calbindin, calretinin, PKCα, bassoon, synapsin, syntaxin and islet1. Full field electroretinography recordings were performed on control and dystrophic mice. Rod and mixed responses, and oscillatory potentials, were recorded in dark adapted conditions; cone and flicker responses were recorded under light adaptation. Our results show significant structural modifications in the photoreceptor populations and neurons of the inner retina. Changes in cell morphology affect mainly to the bipolar cells, which gradually lose their dendritic tufts. The electroretinography records reveal that in the pcd retinas the rod and cone systems show a reduction in the amplitude of the electrical signals. This decrease progresses slowly with the passage of time, although for the most advanced stage of photoreceptor degeneration considered, 270 post-natal days, it is still possible to record light induced responses. We conclude that pcd mice experience a loss of retinal function in correlation with the loss of photoreceptors with age, and significant changes in retinal synaptic processes.
Asunto(s)
Modelos Animales de Enfermedad , Células Fotorreceptoras de Vertebrados/patología , Células de Purkinje/patología , Retina/fisiopatología , Distrofias Retinianas/patología , Células Ganglionares de la Retina/patología , Animales , Biomarcadores/metabolismo , Adaptación a la Oscuridad , Electrorretinografía , Femenino , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Mutantes , Estimulación Luminosa , Reacción en Cadena de la PolimerasaRESUMEN
Apicobasal polarity is essential for epithelial cell function, yet the roles of different proteins in its completion is not fully understood. Here, we have studied the role of the polarity protein, CRB2, in human retinal pigment epithelial (RPE) cells during polarization in vitro, and in mature murine RPE cells in vivo. After establishing a simplified protocol for the culture of human fetal RPE cells, we studied the temporal sequence of the expression and localization of polarity and cell junction proteins during polarization in these epithelial cells. We found that CRB2 plays a key role in tight junction maintenance as well as in cell cycle arrest. In addition, our studies in vivo show that the knockdown of CRB2 in the RPE affects to the distribution of different apical polarity proteins and results in perturbed retinal homeostasis, manifested by the invasion of activated microglial cells into the subretinal space. Together our results demonstrate that CRB2 is a key protein for the development and maintenance of a polarized epithelium.
RESUMEN
The transcription factor Prox1 acts in rodent retinogenesis, at least in promoting cell cycle withdrawal and horizontal cell production. In the mature retina, this protein is detected at the inner nuclear layer of all vertebrate groups. We have made a neurochemical characterisation of Prox1(+) cell types in two different vertebrate groups: mammals and fish. As well as Prox1(+) horizontal cells, we have observed Prox1(+)/PKC-alpha(+) rod bipolar cells in mouse and cone ON and mixed b bipolar cells in goldfish. In mouse, only some CB(+) and CR(+) amacrine cells are Prox1(+) and the TH(+) and CR(+) amacrine cells are Prox1(-). However, in goldfish all CR(+) amacrine cells and TH(+) interplexiform cells are Prox1(+) and in the GCL displaced amacrine cells are also Prox1(+). Besides its expression in different interneuron subpopulations, we demonstrate, for the first time, the presence of Prox1 in the GS(+) and CRALBP(+) Müller cells in the retina of adult mammals and in developing and mature retina of fish. The presence of Prox1 in these cells appears to be related to survival or maintenance of their phenotype. We also demonstrate that in fish, where retinal formation persists into adulthood, Prox1 is expressed in dividing PCNA(+) cells at the peripheral growing zone, in rod progenitors at the inner and outer nuclear layers as well as in early progenitors during a retinal regeneration process after cryo-lesion of the peripheral growing zone. Therefore, Prox1 functions in vertebrate retinogenesis may be more complex than previously expected.
Asunto(s)
Células Amacrinas/metabolismo , Proteínas de Homeodominio/metabolismo , Neuroglía/metabolismo , Células Bipolares de la Retina/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Células Madre/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Recuento de Células , Técnica del Anticuerpo Fluorescente Indirecta , Carpa Dorada , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos C57BL , Pez CebraRESUMEN
INTRODUCTION: Data concerning the use of peripherally inserted central catheters (PICC) for the administration of intravenous (IV) antimicrobials in the acute care setting is scarce. METHODS: We performed a single-center retrospective case-control study (1:1). Case subjects were defined as patients who received IV antimicrobial treatment through a PICC line placed and maintained by specifically trained nurses (PICC group). Control subjects were defined as patients who received antimicrobial therapy by a peripheral or a central venous catheter (CVC) (control group). Control subjects were matched by type of antimicrobial, causative microorganism of the infection that was being treated and duration of treatment. An event leading to undesired catheter removal (ELUCR) was defined as any circumstance which lead to the removal of the indwelling catheter other than the completion of the scheduled course of antimicrobial therapy. RESULTS: The study included 50 patients in each group. The total follow-up time was 1376 catheter-days for the PICC group and 1362 catheter-days for the control group. We observed a significantly lower incidence of ELUCR in the PICC group (0.2 versus 7.7 events per 100 catheter-days; P<0.001). When the incidence of ELUCR was analyzed according to the duration of indwelling catheterisation for each type of catheter (divided into one-week intervals), differences between both groups were also significant (P-values≤0.001 for the first three weeks of treatment). During the second week of IV treatment, only one patient in the PICC group (2.1%) developed an ELUCR compared to 19 (38.8%) in the control group (P<0.001). CONCLUSIONS: A PICC placed and maintained by a dedicated nursing team is an excellent alternative to peripheral venous catheters or CVCs for administrating antimicrobial therapy for both short and long periods of treatment.
Asunto(s)
Antiinfecciosos , Cateterismo Venoso Central , Catéteres Venosos Centrales , Antiinfecciosos/administración & dosificación , Estudios de Casos y Controles , Cateterismo Periférico , Humanos , Estudios RetrospectivosRESUMEN
The visual system of teleost fish shows growth and regeneration capacities during the entire animal's life. Thus, the visual system of adult fish serves as a model for studying neurogenesis in the vertebrate central nervous system (CNS). Our study focused on the expression pattern of Sox2 in the fish visual system. Sox2 is a transcription factor known for its function in keeping stem cell properties, and as a regulator of cell fate during development, especially in the visual system. We used two different fish species: Astatotilapia burtoni and Danio rerio. In the visual system of fish, we identified Sox2 positive cells in the stem cell niche in the peripheral retina, in Müller cells and amacrine cells in the differentiated retina, and glial cells in the optic nerve (ON). We did not observe hardly any Sox2 expression in the optic nerve head (ONH). In the ON, Sox2 positive glial cells were lining the fascicles of new axons. Taking together, the broad spectrum of Sox2 expression indicates that this protein has different functions in the CNS of adult vertebrates. The results suggest that Sox2 has functions associated with the pathway of new axons from the retina. To understand the variety of cell types and subtypes and their plasticity potential in the visual system of fish will be essential to comprehend the growing and regenerating CNS in adult vertebrates.
Asunto(s)
Cíclidos/metabolismo , Proteínas de Peces/metabolismo , Nervio Óptico/metabolismo , Retina/metabolismo , Factores de Transcripción SOX/metabolismo , Proteínas de Pez Cebra/metabolismo , Células Amacrinas/metabolismo , Animales , Células Ependimogliales/metabolismo , Neurogénesis , Neuroglía/metabolismo , Neuronas/metabolismo , Vías Visuales/metabolismo , Pez Cebra/metabolismoRESUMEN
PURPOSE: To evaluate the therapeutic effect of subconjunctival injection of human mesenchymal stromal cells (hMSCs) in the cornea of mice with graft versus host disease (GVHD). METHODS: GVHD was induced in mice after hematopoietic stem cell transplantation (HSCT) between MHC-mismatched mouse strains. Subconjunctival injection of hMSCs was applied at day 10 post-HSCT. Infiltration of CD3+ cells in the cornea and epithelial alterations were analyzed by immunofluorescence. Tear was assessed using the PRT test and TearLab Osmolarity System. qPCR was used to evaluate changes in cytokines, Pax6 and Sprr1b expression. To evaluate the effect of irradiation, we analyzed the expression of these genes in TBI mice. RESULTS: Immune cell invasion occurs in mice with GVHD, as shown by the presence of CD3+ cells in the cornea. Interestingly, eyes treated with hMSC did not present CD3+ cells. Tear osmolarity was increased in GVHD eyes, but not in treated eyes. TNFa expression was highly increased in all corneas except in Control and treated eyes. Pax6 in corneal epithelium showed a similar pattern in GVHD and Control mice, and its gene expression was enhanced in GVHD corneas. In contrast, Pax6 was reduced in GVHD + MSC corneas. We also found an increase in SPRR1B staining in GVHD eyes that was lower in GVHD + MSC mice, demonstrating that corneal keratinization is less frequent after treatment with hMSC. CONCLUSIONS: The treatment with hMSCs by subconjunctival injection is effective in reducing corneal inflammation and squamous metaplasia in ocular GVHD (oGVHD). Local treatment with hMSCs is a promising strategy for oGVHD.
Asunto(s)
Córnea/patología , Trasplante de Córnea/efectos adversos , Enfermedad Injerto contra Huésped/cirugía , Trasplante de Células Madre Hematopoyéticas/métodos , Lágrimas/metabolismo , Animales , Diferenciación Celular , Conjuntiva , Córnea/metabolismo , Enfermedades de la Córnea/cirugía , Modelos Animales de Enfermedad , Femenino , Enfermedad Injerto contra Huésped/metabolismo , Enfermedad Injerto contra Huésped/patología , Inyecciones , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Resultado del TratamientoRESUMEN
Acquisition of cell polarization is essential for the performance of crucial functions, like a successful secretion and appropriate cell signaling in many tissues, and it depends on the correct functioning of polarity proteins, including the Crumbs complex. The CRB proteins, CRB1, CRB2 and CRB3, identified in mammals, are expressed in epithelial-derived tissues like brain, kidney and retina. CRB2 has a ubiquitous expression and has been detected in embryonic brain tissue; but currently there is no data regarding its localization in the adult brain. In our study, we characterized the presence of CRB2 in adult mice brain, where it is particularly enriched in cortex, hippocampus, hypothalamus and cerebellum. Double immunofluorescence analysis confirmed that CRB2 is a neuron-specific protein, present in both soma and projections where colocalizes with certain populations of exocytic and endocytic vesicles and with other members of the Crumbs complex. Finally, in the cortex of CRB1rd8 mutant mice that contain a mutation in the Crb1 gene generating a truncated CRB1 protein, there is an abnormal increase in the expression levels of the CRB2 protein which suggests a possible compensatory mechanism for the malfunction of CRB1 in this mutant background.
Asunto(s)
Encéfalo/metabolismo , Polaridad Celular/genética , Proteínas de la Membrana/genética , Neuronas/metabolismo , Animales , Cerebelo/metabolismo , Células Epiteliales/patología , Regulación de la Expresión Génica/genética , Hipocampo/metabolismo , Hipotálamo/metabolismo , Ratones , Mutación , Neuronas/patología , Transducción de Señal/genéticaRESUMEN
We analyzed the modifications of the retinal neurons in a heterozygous mutant small eye mouse, the Sey(Dey). This mouse presents a mutation in chromosome 2 which affects the gene Pax6 and other nearby genes, such as the Wt1 gene and the gene of the Reticulocalbin. The eyes of these animals do not have lenses and their retinas present important morphological alterations: in the anterior portion they are joined to the cornea, they are found detached from the pigment epithelium, they present folds that form rosettes in some zones and alteration of the lamination can be observed. The partial loss of the genes affected does not prevent the formation of the different layers of the retina, but does affect its thickness, principally of the plexiform layers; moreover, the internal limiting membrane is found disorganized. All the neuronal populations are present in the retina of these animals and express the same neurochemical markers as the control animals, but the number of Pax6(+) cells is notably reduced. In these retinas a marked disorganization of the distribution of the dendrites and axons is observed and a notable reduction in the axons of ganglion cells. These results suggest that, although it does not appear determinant in the differentiation of the distinct neuronal types of the retina, the partial lack of genes of the heterozygotes +/Sey(Dey) provokes important morphological and neurochemical modifications in the cytoarchitecture of the retina.
Asunto(s)
Anomalías del Ojo/patología , Proteínas del Ojo/genética , Regulación del Desarrollo de la Expresión Génica/genética , Proteínas de Homeodominio/genética , Mutación/genética , Neuronas/patología , Factores de Transcripción Paired Box/genética , Proteínas Represoras/genética , Retina/anomalías , Animales , Axones/metabolismo , Axones/patología , Biomarcadores/metabolismo , Calbindina 2 , Calbindinas , Proteínas de Unión al Calcio/genética , Diferenciación Celular/genética , Dendritas/metabolismo , Dendritas/patología , Modelos Animales de Enfermedad , Anomalías del Ojo/metabolismo , Anomalías del Ojo/fisiopatología , Femenino , Masculino , Ratones , Ratones Mutantes Neurológicos , Neuronas/metabolismo , Factor de Transcripción PAX6 , Parvalbúminas/genética , Proteína Quinasa C-alfa/genética , Retina/metabolismo , Retina/fisiopatología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Proteína G de Unión al Calcio S100/genética , Tirosina 3-Monooxigenasa/genética , Proteínas WT1/genéticaRESUMEN
The mammalian central nervous system (CNS) is unable to regenerate. In contrast, the CNS of fish, including the visual system, is able to regenerate after damage. Moreover, the fish visual system grows continuously throughout the life of the animal, and it is therefore an excellent model to analyze processes of myelination and re-myelination after an injury. Here we analyze Sox10+ oligodendrocytes in the goldfish retina and optic nerve in controls and after two kinds of injuries: cryolesion of the peripheral growing zone and crushing of the optic nerve. We also analyze changes in a major component of myelin, myelin basic protein (MBP), as a marker for myelinated axons. Our results show that Sox10+ oligodendrocytes are located in the retinal nerve fiber layer and along the whole length of the optic nerve. MBP was found to occupy a similar location, although its loose appearance in the retina differed from the highly organized MBP+ axon bundles in the optic nerve. After optic nerve crushing, the number of Sox10+ cells decreased in the crushed area and in the optic nerve head. Consistent with this, myelination was highly reduced in both areas. In contrast, after cryolesion we did not find changes in the Sox10+ population, although we did detect some MBP- degenerating areas. We show that these modifications in Sox10+ oligodendrocytes are consistent with their role in oligodendrocyte identity, maintenance and survival, and we propose the optic nerve head as an excellent area for research aimed at better understanding of de- and remyelination processes.
Asunto(s)
Disco Óptico/metabolismo , Retina/metabolismo , Factores de Transcripción SOXE/metabolismo , Animales , Proliferación Celular , Carpa Dorada , Oligodendroglía/metabolismo , Disco Óptico/patología , Retina/patologíaRESUMEN
The CRB proteins CRB1, CRB2 and CRB3 are members of the cell polarity complex Crumbs in mammals that together with Scribble and Par complexes stablish the polarity of a variety of cell types. Although many members of the Crumbs complex proteins are expressed in the retinal pigment epithelium (RPE), and even though the mRNA of CRB2 has been detected in ARPE-19 cells and in the RPE/Choroid, to date no CRB protein has yet been found in this tissue. To investigate this possibility, we generated an antibody that specifically recognize the mouse CRB2 protein, and we demonstrate the expression of CRB2 in mouse RPE. Confocal analysis shows that CRB2 is restricted to the apicolateral membrane of RPE cells, and more precisely, in the tight junctions. Our study identified CRB2 as the member of the CRB protein family that is present together with the rest of the components of the Crumbs complex in the RPE apico-lateral cell membrane. Considering that the functions of CRB proteins are decisive in the establishment and maintenance of cell-cell junctions in several epithelial-derived cell types, we believe that these findings are a relevant starting point for unraveling the functions that CRB2 might perform in the RPE.
Asunto(s)
Expresión Génica , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Uniones Adherentes/metabolismo , Animales , Membrana Celular/metabolismo , Glicoproteínas de Membrana , Ratones , Transporte de ProteínasRESUMEN
Clinical trials have assessed the use of human bone marrow stromal cells (hBMSCs) for the treatment of immune-related disorders such as graft-versus-host disease (GVHD). In the current study, we show that GFP(+)-transduced hBMSCs generated from bone marrow migrate and differentiate into corneal tissue after subconjunctival injection in mice. Interestingly, these hBMSCs display morphological features of epithelial, stromal, and endothelial cells and appear at different layers and with different morphologies depending on their position within the epithelium. Furthermore, these cells display ultrastructural properties, such as bundles of intermediate filaments, interdigitations, and desmosomes with GFP(-) cells, which confirms their differentiation into corneal tissues. GFP(+)-transduced hBMSCs were injected at different time points into the right eye of lethally irradiated mice undergoing bone marrow transplantation, which developed ocular GVHD (oGVHD). Remarkably, hBMSCs massively migrate to corneal tissues after subconjunctival injection. Both macroscopic and histopathological examination showed minimal or no evidence of GVHD in the right eye, while the left eye, where no hBMSCs were injected, displayed features of GVHD. Thus, in the current study, we confirm that hBMSCs may induce their therapeutic effect at least in part by differentiation and regeneration of damaged tissues in the host. Our results provide experimental evidence that hBMSCs represent a potential cellular therapy to attenuate oGVHD.
Asunto(s)
Células de la Médula Ósea/citología , Córnea/citología , Trasplante de Córnea/efectos adversos , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Adulto , Animales , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Enfermedad Injerto contra Huésped/terapia , Proteínas Fluorescentes Verdes , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Persona de Mediana EdadRESUMEN
This study demonstrates the peculiarities of the glial organization of the optic nerve head (ONH) of a fish, the tench (Tinca tinca), by using immunohistochemistry and electron microscopy. We employed antibodies specific for the macroglial cells: glutamine synthetase (GS), glial fibrillary acidic protein (GFAP), and S100. We also used the N518 antibody to label the new ganglion cells' axons, which are continuously added to the fish retina, and the anti-proliferating cell nuclear antigen (PCNA) antibody to specifically locate dividing cells. We demonstrate a specific regional adaptation of the GS-S100-positive Müller cells' vitreal processes around the optic disc, strongly labeled with the anti-GFAP antibody. In direct contact with these Müller cells' vitreal processes, there are S100-positive astrocytes and S100-negative cells ultrastructurally identified as microglial cells. Moreover, a population of PCNA-positive cells, characterized as glioblasts, forms the limit between the retina and the optic nerve in a region homologous to the Kuhnt intermediary tissue of mammals. Finally, in the intraocular portion of the optic nerve there are differentiating oligodendrocytes arranged in rows. Both the glioblasts and the rows of developing cells could serve as a pool of glial elements for the continuous growth of the visual system.