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1.
ArXiv ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39279835

RESUMEN

Intracorporeal needle-based therapeutic ultrasound (NBTU) is a minimally invasive option for intervening in malignant brain tumors, commonly used in thermal ablation procedures. This technique is suitable for both primary and metastatic cancers, utilizing a high-frequency alternating electric field (up to 10 MHz) to excite a piezoelectric transducer. The resulting rapid deformation of the transducer produces an acoustic wave that propagates through tissue, leading to localized high-temperature heating at the target tumor site and inducing rapid cell death. To optimize the design of NBTU transducers for thermal dose delivery during treatment, numerical modeling of the acoustic pressure field generated by the deforming piezoelectric transducer is frequently employed. The bioheat transfer process generated by the input pressure field is used to track the thermal propagation of the applicator over time. Magnetic resonance thermal imaging (MRTI) can be used to experimentally validate these models. Validation results using MRTI demonstrated the feasibility of this model, showing a consistent thermal propagation pattern. However, a thermal damage isodose map is more advantageous for evaluating therapeutic efficacy. To achieve a more accurate simulation based on the actual brain tissue environment, a new finite element method (FEM) simulation with enhanced damage evaluation capabilities was conducted. The results showed that the highest temperature and ablated volume differed between experimental and simulation results by 2.1884°C (3.71%) and 0.0631 cm3 (5.74%), respectively. The lowest Pearson correlation coefficient (PCC) for peak temperature was 0.7117, and the lowest Dice coefficient for the ablated area was 0.7021, indicating a good agreement in accuracy between simulation and experiment.

2.
Autophagy ; : 1-19, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265983

RESUMEN

Uveal melanoma (UM) is an aggressive intraocular malignancy derived from melanocytes in the uvea tract of the eye. Up to 50% of patients with UM develop distant metastases which is usually fatal within one year; preventing metastases is therefore essential. Metabolic reprogramming plays a critical role in UM progression and metastasis. However, the metabolic phenotype of UM cells in the hypoxic tumor is not well understood. Here, we report that hypoxia-induced BNIP3 reprograms tumor cell metabolism, promoting their survival and metastasis. In response to hypoxia, BNIP3-mediated mitophagy alleviates mitochondrial dysfunction and enhances mitochondrial oxidative phosphorylation (OXPHOS) while simultaneously reducing mitochondrial reactive oxygen species (mtROS) production. This, in turn, impairs HIF1A/HIF-1α protein stability and inhibits glycolysis. Inhibition of mitophagy significantly suppresses BNIP3-induced UM progression and metastasis in vitro and in vivo. Collectively, these observations demonstrate a novel mechanism whereby BNIP3 promotes UM metabolic reprogramming and malignant progression by mediating hypoxia-induced mitophagy and suggest that BNIP3 could be an important therapeutic target to prevent metastasis in patients with UM.Abbreviations: AOD: average optical density; BNIP3: BCL2/adenovirus E1B interacting protein 3; CQ: chloroquine; CoCl2: cobalt chloride; GEPIA: Gene Expression Profiling Interactive Analysis; HIF1A: hypoxia inducible factor 1, alpha subunit; IHC: immunohistochemistry; mtROS: mitochondrial reactive oxygen species; NAC: N-acetylcysteine; OCR: oxygen consumption rate; OXPHOS: oxidative phosphorylation; ROS: reactive oxygen species; TCGA: The Cancer Genome Atlas; UM: uveal melanoma.

3.
Case Rep Rheumatol ; 2024: 2043012, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161396

RESUMEN

Giant cell arteritis (GCA) is a chronic granulomatous vasculitis of medium and large arteries leading to cranial and extracranial manifestations. Temporal artery biopsy is considered the gold standard; however, its sensitivity is low at 47%. We report a unique case of Bing-Neel Syndrome (BNS) presenting as biopsy-proven GCA. BNS is a rare complication (1%) of Waldenstrom Macroglobulinemia (WM), which results from infiltration of lymph plasmacytoid cells and plasma cells into the central nervous system. A 77-year-old female with a past medical history of glaucoma, hypertension, diabetes, and chronic ocular ischemic syndrome in her right eye presented with progressive left eye vision loss for 5 days. Fundoscopic examination was notable for pseudophakic pseudopallor but no optic disc edema. Intraocular pressure was >40 and normalized after acetazolamide. The patient was started on pulse dose steroids by her neuro-ophthalmologist. She was discharged home on 60 mg of prednisone. At follow up with her neuro-ophthalmologist, new dot blot hemorrhages in the left eye were noted and she was readmitted for pulse dose of intravenous methylprednisolone. Temporal artery biopsy was consistent with GCA spectrum. Work up revealed paraproteinemia and subsequent bone marrow biopsy demonstrated WM. The patient was treated for her WM and her ophthalmic complications stabilized.

4.
Development ; 151(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39007366

RESUMEN

Many tissue-specific adult stem cell lineages maintain a balance between proliferation and differentiation. Here, we study how the H3K4me3 methyltransferase Set1 regulates early-stage male germ cells in Drosophila. Early-stage germline-specific knockdown of Set1 results in temporally progressive defects, arising as germ cell loss and developing into overpopulated early-stage germ cells. These germline defects also impact the niche architecture and cyst stem cell lineage non-cell-autonomously. Additionally, wild-type Set1, but not the catalytically inactive Set1, rescues the Set1 knockdown phenotypes, highlighting the functional importance of the methyltransferase activity of Set1. Further, RNA-sequencing experiments reveal key signaling pathway components, such as the JAK-STAT pathway gene Stat92E and the BMP pathway gene Mad, which are upregulated upon Set1 knockdown. Genetic interaction assays support the functional relationships between Set1 and JAK-STAT or BMP pathways, as both Stat92E and Mad mutations suppress the Set1 knockdown phenotypes. These findings enhance our understanding of the balance between proliferation and differentiation in an adult stem cell lineage. The phenotype of germ cell loss followed by over-proliferation when inhibiting a histone methyltransferase also raises concerns about using their inhibitors in cancer therapy.


Asunto(s)
Diferenciación Celular , Proteínas de Drosophila , Drosophila melanogaster , Células Germinativas , N-Metiltransferasa de Histona-Lisina , Transducción de Señal , Animales , Masculino , Diferenciación Celular/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Transducción de Señal/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Células Germinativas/metabolismo , Células Germinativas/citología , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Células Madre/metabolismo , Células Madre/citología , Factores de Transcripción STAT/metabolismo , Factores de Transcripción STAT/genética , Quinasas Janus/metabolismo , Quinasas Janus/genética , Proliferación Celular/genética , Linaje de la Célula/genética , Regulación del Desarrollo de la Expresión Génica
5.
Bioessays ; 46(9): e2400133, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38990084

RESUMEN

The vertebrate retina is a tractable system for studying control of cell neurogenesis and cell fate specification. During embryonic development, retinal neurogenesis is under strict temporal regulation, with cell types generated in fixed but overlapping temporal intervals. The temporal sequence and relative numbers of retinal cell types generated during development are robust and show minimal experience-dependent variation. In many cold-blooded vertebrates, acute retinal injury induces a different form of neurogenesis, where Müller glia reprogram into retinal progenitor-like cells that selectively regenerate retinal neurons lost to injury. The extent to which the molecular mechanisms controlling developmental and injury-induced neurogenesis resemble one another has long been unclear. However, a recent study in zebrafish has shed new light on this question, using single-cell multiomic analysis to show that selective loss of different retinal cell types induces the formation of fate-restricted Müller glia-derived progenitors that differ both from one another and from progenitors in developing retina. Here, we discuss the broader implications of these findings, and their possible therapeutic relevance.


Asunto(s)
Neurogénesis , Retina , Pez Cebra , Animales , Células Ependimogliales/metabolismo , Células Ependimogliales/citología , Células Ependimogliales/fisiología , Humanos , Regeneración/fisiología , Diferenciación Celular , Neuroglía/metabolismo , Neuroglía/fisiología
6.
Development ; 151(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39007397

RESUMEN

Many genes are known to regulate retinal regeneration after widespread tissue damage. Conversely, genes controlling regeneration after limited cell loss, as per degenerative diseases, are undefined. As stem/progenitor cell responses scale to injury levels, understanding how the extent and specificity of cell loss impact regenerative processes is important. Here, transgenic zebrafish enabling selective retinal ganglion cell (RGC) ablation were used to identify genes that regulate RGC regeneration. A single cell multiomics-informed screen of 100 genes identified seven knockouts that inhibited and 11 that promoted RGC regeneration. Surprisingly, 35 out of 36 genes known and/or implicated as being required for regeneration after widespread retinal damage were not required for RGC regeneration. The loss of seven even enhanced regeneration kinetics, including the proneural factors neurog1, olig2 and ascl1a. Mechanistic analyses revealed that ascl1a disruption increased the propensity of progenitor cells to produce RGCs, i.e. increased 'fate bias'. These data demonstrate plasticity in the mechanism through which Müller glia convert to a stem-like state and context specificity in how genes function during regeneration. Increased understanding of how the regeneration of disease-relevant cell types is specifically controlled will support the development of disease-tailored regenerative therapeutics.


Asunto(s)
Animales Modificados Genéticamente , Células Ganglionares de la Retina , Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/genética , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/fisiología , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Regeneración Nerviosa/genética , Regeneración Nerviosa/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Sistemas CRISPR-Cas/genética , Regeneración/genética , Regeneración/fisiología , Retina/metabolismo , Retina/citología , Células Madre/metabolismo , Células Madre/citología , Factores de Transcripción
7.
Nano Lett ; 24(25): 7757-7763, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38874303

RESUMEN

Terahertz scattering scanning near-field optical microscopy is a robust spectral detection technique with a nanoscale resolution. However, there are still major challenges in investigating the heterogeneity of cell membrane components in individual cells. Here, we present a novel and comprehensive analytical approach for detecting and investigating heterogeneity in cell membrane components at the single-cell level. In comparison to the resolution of the topographical atomic force microscopy image, the spatial resolution of the terahertz near-field amplitude image is 3 times that of the former. This ultrafine resolution enables the compositional distribution in the cell membrane, such as the distribution of extracellular vesicles, to be finely characterized. Furthermore, via extraction of the near-field absorption images at specific frequencies, the visualization and compositional difference analysis of cell membrane components can be presented in detail. These findings have significant implications for the intuitive and visual analysis of cell development and disease evolutionary pathways.


Asunto(s)
Membrana Celular , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Membrana Celular/química , Humanos , Imágen por Terahertz/métodos , Microscopía de Fuerza Atómica/métodos , Vesículas Extracelulares/química
8.
Front Pharmacol ; 15: 1372401, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38803441

RESUMEN

Objective: Bendamustine was approved for treating chronic lymphocytic leukemia and indolent B-cell non-Hodgkin lymphoma. Despite its therapeutic benefits, the long-term safety of bendamustine in a large population remains inadequately understood. This study evaluates the adverse events (AEs) associated with bendamustine, using a real-world pharmacovigilance database to support its clinical application. Methods: We conducted a post-marketing risk analysis to assess the association between bendamustine and its AEs. Data were extracted from the US FDA's Adverse Event Reporting System (FAERS), covering the period from January 2017 to September 2023. The characteristics of bendamustine-associated AEs and the onset time were further analyzed. Statistical analysis was performed using MYSQL 8.0, Navicat Premium 15, Microsoft EXCEL 2016, and Minitab 21.0. Results: 9,461,874 reports were collected from the FAERS database, 9,131 identified bendamustine as the "primary suspected" drug. We identified 331 significant disproportionality preferred terms (PTs). Common AEs included pyrexia, neutropenia, infusion site reaction, progressive multifocal leukoencephalopathy (PML), injection site vasculitis, and pneumonia-all documented on bendamustine's label. Notably, 16 unexpected and significant AEs were discovered, including hypogammaglobulinemia, which is concerning due to its potential to increase infection susceptibility following bendamustine treatment. Other significant findings were anaphylactic reactions, PML, and cutaneous malignancies, suggesting updates to the drug's label may be necessary. Physicians should monitor for neurological and skin changes in patients and discontinue treatment if PML is suspected. Moreover, the median onset time for bendamustine-associated AEs was 13 days, with an interquartile range [IQR] of 0-59 days, predominantly occurring on the first day post-initiation. The ß of bendamustine-related AEs suggested risk reduction over time. Conclusion: Our study uncovered some potential pharmacovigilance signals for bendamustine, providing important insights for its safe and effective clinical use.

9.
Clin Case Rep ; 12(5): e8847, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38770416

RESUMEN

Key Clinical Message: Unlike most cases, the lesions were localized to the dorsum of the hand, lacked pruritus (itching), and did not exhibit "sperm-like blood vessels," which are typically pathognomonic to classical MF. Abstract: The study presents a rare case involving a 44-year-old woman who developed a skin condition on the base of her left thumb. Initially misdiagnosed as pigmented purpura, the need for further investigation arose to determine the nature of the condition accurately. The medical evaluation encompassed a comprehensive analysis of the patient's skin ailment. A series of diagnostic examinations were conducted to ascertain the underlying cause. Although routine blood tests yielded unremarkable results, the distinct characteristics of the rash prompted a more thorough investigation. Subsequent assessment revealed that the skin condition was not pigmented purpura, as initially presumed, but rather a manifestation of cutaneous T-cell lymphoma (CTCL) known as mycosis fungoides (MF). MF is an infrequent lymphoma predominantly affecting individuals aged 45-65, exhibiting a male-to-female sex ratio of 2:1. The annual incidence of MF ranges from 0.3 to 0.96 cases per 100,000 individuals. The woman's skin exhibited discrete patches adorned with colored dots, progressively thickening and pigmentation. Notably, the absence of pruritus did not dispel suspicion. This case underscores the significance of accurately diagnosing uncommon dermatological disorders to facilitate appropriate medical intervention. The unique appearance of the rash and its distinctive features, despite normal blood results, enabled the identification of MF. The patient's treatment encompassed a combination of steroids and narrowband UV therapy. Vigilance, continued research, and heightened awareness are paramount for early intervention and improved patient outcomes. Such efforts contribute to an enhanced understanding of the complexities of this condition.

10.
Am J Ophthalmol ; 266: 10-16, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38615831

RESUMEN

PURPOSE: To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC). DESIGN: Retrospective clinical cohort study. METHODS: This study included 12 unilateral RB eyes treated with IAC (RB tumor), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including the foveal avascular zone (FAZ) area, macular and peripapillary superficial vessel density (SVD), and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the 3 groups was conducted, and the correlations among the parameters were analyzed. RESULTS: Among the 3 cohorts, the foveal retinal thickness, SVD, DVD, ChT, TCA, LA, SA, and CVI were significantly lower in RB tumor compared to RB fellow and the control eyes (all P < .01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA. CONCLUSIONS: The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. There were no measurable changes in the contralateral eyes.


Asunto(s)
Coroides , Angiografía con Fluoresceína , Infusiones Intraarteriales , Melfalán , Microvasos , Neoplasias de la Retina , Vasos Retinianos , Retinoblastoma , Tomografía de Coherencia Óptica , Humanos , Retinoblastoma/tratamiento farmacológico , Neoplasias de la Retina/tratamiento farmacológico , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Coroides/irrigación sanguínea , Masculino , Femenino , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/efectos de los fármacos , Angiografía con Fluoresceína/métodos , Preescolar , Melfalán/administración & dosificación , Microvasos/efectos de los fármacos , Lactante , Niño , Antineoplásicos Alquilantes/administración & dosificación , Densidad Microvascular , Agudeza Visual/fisiología
11.
Br J Ophthalmol ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499321

RESUMEN

AIMS: To describe the clinical features, multimodal imaging, treatments and natural course of acute spontaneous vortex vein occlusion. METHODS: Clinical data were collected on nine patients with acute vortex vein occlusion. The symptoms and signs, multimodal imaging, treatments and follow-up results were summarised. RESULTS: Six patients (66.7%) were men and three (33.3%) were women. The mean age was 47.8±15.4 years. Patients were initially misdiagnosed as having choroidal tumour (66.7%), scleritis (22.2%) and peripheral exudative haemorrhagic chorioretinopathy (11.1%). The related clinical characteristics included choroidal pseudo-tumour (100%), anterior segment injection (88.9%), acute ocular pain (77.8%), transient blurred vision (66.7%) and subsequent scleral icterus (66.7%). Six patients (66.7%) experienced a definite Valsalva manoeuvre prior to the onset. In acute phase, ultrasonography showed a low-to-medium reflective lesion without inside blood flow signal (mean thickness, 2.7±0.6 mm). Swept-source optical coherence tomography angiography (SS-OCTA) demonstrated the dilated vortex veins and ampulla with suprachoroidal haemorrhage and exudation. Indocyanine green angiography (ICGA) demonstrated choroidal circulation abnormalities in the affected quadrant. MRI showed a well-defined mass with enhancement. The main treatment was medical observation (44.5%). The choroidal pseudo-tumour spontaneously resolved with a mean course of 4.1±1.9 weeks. CONCLUSIONS: Acute vortex vein occlusion is a rare condition and initial misdiagnosis is not uncommon. It is mainly identified as an evanescent choroidal pseudo-tumour with acute pain, red eye and blurred vision. Widefield ICGA and SS-OCTA can offer valuable diagnostic clues. Medical observation may be a treatment option.

12.
Nat Commun ; 15(1): 2206, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467611

RESUMEN

Previous studies of neuronal survival have primarily focused on identifying intrinsic mechanisms controlling the process. This study explored how intercellular communication contributes to retinal ganglion cell (RGC) survival following optic nerve crush based on single-cell RNA-seq analysis. We observed transcriptomic changes in retinal cells in response to the injury, with astrocytes and Müller glia having the most interactions with RGCs. By comparing RGC subclasses characterized by distinct resilience to cell death, we found that the high-survival RGCs tend to have more ligand-receptor interactions with neighboring cells. We identified 47 interactions stronger in high-survival RGCs, likely mediating neuroprotective effects. We validated one identified target, the µ-opioid receptor (Oprm1), to be neuroprotective in three retinal injury models. Although the endogenous Oprm1 is preferentially expressed in intrinsically photosensitive RGCs, its neuroprotective effect can be transferred to other subclasses by pan-RGC overexpression of Oprm1. Lastly, manipulating the Oprm1 activity improved visual functions in mice.


Asunto(s)
Fármacos Neuroprotectores , Traumatismos del Nervio Óptico , Animales , Ratones , Comunicación Celular , Muerte Celular , Supervivencia Celular , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/metabolismo , Nervio Óptico/metabolismo , Traumatismos del Nervio Óptico/metabolismo , Células Ganglionares de la Retina/fisiología
13.
bioRxiv ; 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38405894

RESUMEN

Many cell types come from tissue-specific adult stem cells that maintain the balance between proliferation and differentiation. Here, we study how the H3K4me3 methyltransferase, Set1, regulates early-stage male germ cell proliferation and differentiation in Drosophila. Early-stage germline-specific knockdown of set1 results in a temporally progressed defects, arising as germ cell loss and developing to overpopulated early-stage germ cells. These germline defects also impact the niche architecture and cyst stem cell lineage in a non-cell-autonomous manner. Additionally, wild-type Set1, but not the catalytically inactive Set1, could rescue the set1 knockdown phenotypes, highlighting the functional importance of the methyl-transferase activity of the Set1 enzyme. Further, RNA-seq experiments reveal key signaling pathway components, such as the JAK-STAT pathway gene stat92E and the BMP pathway gene mad, that are upregulated upon set1 knockdown. Genetic interaction assays support the functional relationships between set1 and JAK-STAT or BMP pathways, as mutations of both the stat92E and mad genes suppress the set1 knockdown phenotypes. These findings enhance our understanding of the balance between proliferation and differentiation in an adult stem cell lineage. The germ cell loss followed by over-proliferation phenotypes when inhibiting a histone methyl-transferase raise concerns about using their inhibitors in cancer therapy.

14.
World Neurosurg ; 183: e761-e771, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211812

RESUMEN

BACKGROUND: Stroke presentation secondary to a cardiac myxoma thromboembolism is rare in the pediatric population. Because of such rarity, the reported cases in the literature are primarily case reports. Additionally, general pediatric stroke management lacks evidence-based guidelines because of its low incidence and lack of clinical trials. In pediatric strokes identified from a cardiac myxoma, the incidence favors boys with the classical presentation of unilateral weakness and aphasia. We present a pediatric patient who presented with strokelike symptoms secondary to an intracranial embolus from a previously undiagnosed cardiac myxoma. METHODS: We performed a systematic review by searching PubMed, Google Scholar, Web of Science, and Embase databases for cases of pediatric myxoma causing stroke (n = 2431) and identified 19 reported uses of surgical management in treating pediatric patients who present with stroke symptoms secondary to a cardiac myxoma thromboembolism. RESULTS: The most common imaging modality was magnetic resonance imaging in 42% of cases, computed tomography in 36.8%, followed by computed tomography angiography in 31.6% of cases. Of these 19 children treated with procedures, 36.8% of pediatric patients aged between 4 and 14 years underwent neurosurgery (n = 7). CONCLUSIONS: We describe an urgent mechanical thrombectomy and share preoperative and postoperative images and pathology slides confirming a stroke from myxoma origin. We provide added insight in the safe use of mechanical thrombectomy as treatment for pediatric strokes secondary to a thromboembolism.


Asunto(s)
Neoplasias Cardíacas , Embolia Intracraneal , Mixoma , Accidente Cerebrovascular , Trombectomía , Humanos , Mixoma/complicaciones , Mixoma/cirugía , Mixoma/diagnóstico por imagen , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/cirugía , Neoplasias Cardíacas/diagnóstico por imagen , Trombectomía/métodos , Niño , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/diagnóstico por imagen , Embolia Intracraneal/etiología , Embolia Intracraneal/cirugía , Embolia Intracraneal/diagnóstico por imagen , Masculino , Adolescente , Preescolar , Femenino
15.
bioRxiv ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-37886472

RESUMEN

Schlemm's canal (SC) is central in intraocular pressure regulation but requires much characterization. It has distinct inner and outer walls, each composed of Schlemm's canal endothelial cells (SECs) with different morphologies and functions. Recent transcriptomic studies of the anterior segment added important knowledge, but were limited in power by SEC numbers or did not focus on SC. To gain a more comprehensive understanding of SC biology, we performed bulk RNA sequencing on C57BL/6J SC, blood vessel, and lymphatic endothelial cells from limbal tissue (~4500 SECs). We also analyzed mouse limbal tissues by single-cell and single-nucleus RNA sequencing (C57BL/6J and 129/Sj strains), successfully sequencing 903 individual SECs. Together, these datasets confirm that SC has molecular characteristics of both blood and lymphatic endothelia with a lymphatic phenotype predominating. SECs are enriched in pathways that regulate cell-cell junction formation pointing to the importance of junctions in determining SC fluid permeability. Importantly, and for the first time, our analyses characterize 3 molecular classes of SECs, molecularly distinguishing inner wall from outer wall SECs and discovering two inner wall cell states that likely result from local environmental differences. Further, and based on ligand and receptor expression patterns, we document key interactions between SECs and cells of the adjacent trabecular meshwork (TM) drainage tissue. Also, we present cell type expression for a collection of human glaucoma genes. These data provide a new molecular foundation that will enable the functional dissection of key homeostatic processes mediated by SECs as well as the development of new glaucoma therapeutics.

16.
J Clin Invest ; 134(3)2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38015636

RESUMEN

Current treatments for neurodegenerative diseases and neural injuries face major challenges, primarily due to the diminished regenerative capacity of neurons in the mammalian CNS as they mature. Here, we investigated the role of Ezh2, a histone methyltransferase, in regulating mammalian axon regeneration. We found that Ezh2 declined in the mouse nervous system during maturation but was upregulated in adult dorsal root ganglion neurons following peripheral nerve injury to facilitate spontaneous axon regeneration. In addition, overexpression of Ezh2 in retinal ganglion cells in the CNS promoted optic nerve regeneration via both histone methylation-dependent and -independent mechanisms. Further investigation revealed that Ezh2 fostered axon regeneration by orchestrating the transcriptional silencing of genes governing synaptic function and those inhibiting axon regeneration, while concurrently activating various factors that support axon regeneration. Notably, we demonstrated that GABA transporter 2, encoded by Slc6a13, acted downstream of Ezh2 to control axon regeneration. Overall, our study underscores the potential of modulating chromatin accessibility as a promising strategy for promoting CNS axon regeneration.


Asunto(s)
Axones , Traumatismos del Nervio Óptico , Animales , Ratones , Axones/metabolismo , Ganglios Espinales/metabolismo , Mamíferos , Regeneración Nerviosa/genética , Traumatismos del Nervio Óptico/genética , Traumatismos del Nervio Óptico/metabolismo , Células Ganglionares de la Retina/metabolismo
17.
J Comp Neurol ; 532(2): e25552, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37916792

RESUMEN

Early postnatal brain development involves complex interactions among maturing neurons and glial cells that drive tissue organization. We previously analyzed gene expression in tissue from the mouse medial nucleus of the trapezoid body (MNTB) during the first postnatal week to study changes that surround rapid growth of the large calyx of Held (CH) nerve terminal. Here, we present genes that show significant changes in gene expression level during the second postnatal week, a developmental timeframe that brackets the onset of airborne sound stimulation and the early stages of myelination. Gene Ontology analysis revealed that many of these genes are related to the myelination process. Further investigation of these genes using a previously published cell type-specific bulk RNA-Seq data set in cortex and our own single-cell RNA-Seq data set in the MNTB revealed enrichment of these genes in the oligodendrocyte lineage (OL) cells. Combining the postnatal day (P)6-P14 microarray gene expression data with the previously published P0-P6 data provided fine temporal resolution to investigate the initiation and subsequent waves of gene expression related to OL cell maturation and the process of myelination. Many genes showed increasing expression levels between P2 and P6 in patterns that reflect OL cell maturation. Correspondingly, the first myelin proteins were detected by P4. Using a complementary, developmental series of electron microscopy 3D image volumes, we analyzed the temporal progression of axon wrapping and myelination in the MNTB. By employing a combination of established ultrastructural criteria to classify reconstructed early postnatal glial cells in the 3D volumes, we demonstrated for the first time that astrocytes within the mouse MNTB extensively wrap the axons of the growing CH terminal prior to OL cell wrapping and compaction of myelin. Our data revealed significant expression of several myelin genes and enrichment of multiple genes associated with lipid metabolism in astrocytes, which may subserve axon wrapping in addition to myelin formation. The transition from axon wrapping by astrocytes to OL cells occurs rapidly between P4 and P9 and identifies a potential new role of astrocytes in priming calyceal axons for subsequent myelination.


Asunto(s)
Astrocitos , Vaina de Mielina , Animales , Ratones , Axones/ultraestructura , Oligodendroglía/fisiología , Tronco Encefálico/fisiología
18.
Br J Ophthalmol ; 108(4): 566-570, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36997291

RESUMEN

AIMS: To describe the clinical features, imaging characteristics, histopathology, treatment and outcomes of intraocular medulloepithelioma. METHODS: Medical records of 11 patients with clinically or histopathologically confirmed medulloepithelioma were retrieved and reviewed. Clinical features, diagnostic challenges, imaging characteristics, management, histopathology and prognosis were assessed. RESULTS: The median age of the patients at initial diagnosis was 4 years, with the most common manifestations being leukocoria (five eyes), loss of vision (four eyes), ocular pain (one eye) and ophthalmic screening (one eye). The clinical signs include a grey-white ciliary body lesion, cataract or lens subluxation, secondary glaucoma and evident cysts. The ultrasound biomicroscopy (UBM) imaging most commonly displays ciliary body mass with intratumoural cysts (nine eyes). Three patients underwent surgery for cataract or glaucoma while the tumours were incidentally found. Two of the three patients managed by eye preserve treatments eventually required enucleation because of local tumour recurrence or phthisis. One patient treated with intra-arterial chemotherapy and cryotherapy had successful tumour regression and globe salvage. CONCLUSIONS: Initial misdiagnosis, delay in diagnosis and subsequent misdirected management is not uncommon in medulloepithelioma. The presence of multiple cysts in the tumour and retrolental neoplastic cyclitic membrane detected by UBM can offer certain information. Selective intra-arterial melphalan may prevent further tumour growth, but longer follow-up is necessary until treatment efficacy is fully evaluated.


Asunto(s)
Catarata , Quistes , Glaucoma , Enfermedades del Iris , Tumores Neuroectodérmicos Primitivos , Neoplasias de la Úvea , Humanos , Preescolar , Cuerpo Ciliar/diagnóstico por imagen , Cuerpo Ciliar/patología , Neoplasias de la Úvea/patología , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagen , Tumores Neuroectodérmicos Primitivos/terapia , Catarata/complicaciones , Glaucoma/diagnóstico , Glaucoma/terapia , Glaucoma/complicaciones
19.
Oncol Rep ; 51(2)2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38099424

RESUMEN

Uveal melanoma (UM) is the most common intraocular malignant tumor in adults, with a lack of effective treatment for metastasis and a poor prognosis. Stimulator of interferon genes (STING, also known as TMEM173) plays an important role in tumor development by regulating cell proliferation, metastasis and other cellular processes. However, the function of STING in UM remains unclear and requires further investigation. The present study analyzed the expression status of STING to elucidate the mechanisms underlying UM. The correlation between STING and the prognosis of UM was evaluated based on UM RNA­seq data and clinical information extracted from The Cancer Genome Atlas database. Quantification of STING in UM cell lines and tissues was performed using the Wes Separation protein immunoassay. The effects of STING on the proliferation, migration and invasion of UM cells were investigated using Cell Counting Kit­8, Transwell and wound healing experiments. Survival analysis demonstrated that high levels of STING in UM tissues indicated a poor prognosis. The expression of STING in UM tissues was higher than that in the choroid membranes. Furthermore, it was found that downregulation of STING expression in UM cells suppressed migration and invasion, whereas overexpression of STING significantly promoted migration and invasion. Notably, STING had no significant effect on UM cell proliferation. It was also identified that STING positively upregulated the phosphorylation of p38 mitogen­activated protein kinase (p38­MAPK) in UM cells, enhancing cell migration and invasion, which the p38­MAPK inhibitor SB203580 reversed. Finally, the results of the present study demonstrated that high STING expression in UM indicates a poor prognosis. STING was revealed to promote the migration and invasion of UM cells through p38­MAPK signaling.


Asunto(s)
Melanoma , Neoplasias de la Úvea , Adulto , Humanos , Línea Celular Tumoral , Melanoma/patología , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/metabolismo , Neoplasias de la Úvea/patología , Sistema de Señalización de MAP Quinasas/genética , Proliferación Celular/genética
20.
bioRxiv ; 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38045256

RESUMEN

Many genes are known to regulate retinal regeneration following widespread tissue damage. Conversely, genes controlling regeneration following limited retinal cell loss, akin to disease conditions, are undefined. Combining a novel retinal ganglion cell (RGC) ablation-based glaucoma model, single cell omics, and rapid CRISPR/Cas9-based knockout methods to screen 100 genes, we identified 18 effectors of RGC regeneration kinetics. Surprisingly, 32 of 33 previously known/implicated regulators of retinal tissue regeneration were not required for RGC replacement; 7 knockouts accelerated regeneration, including sox2, olig2, and ascl1a . Mechanistic analyses revealed loss of ascl1a increased "fate bias", the propensity of progenitors to produce RGCs. These data demonstrate plasticity and context-specificity in how genes function to control regeneration, insights that could help to advance disease-tailored therapeutics for replacing lost retinal cells. One sentence summary: We discovered eighteen genes that regulate the regeneration of retinal ganglion cells in zebrafish.

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