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1.
Hum Pathol ; 152: 105636, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39127354

RESUMEN

Tumors with pathogenic DICER1 mutation are rare and encompass sporadic or hereditary benign, intermediate and malignant tumors. DICER1-associated sarcomas are heterogeneous; however, the prototypical ones in the GYN-tract include embryonal rhabdomyosarcoma, adenosarcoma and moderately to poorly differentiated Sertoli-Leydig tumor. In this report, we present three unique uterine sarcomas with DICER1 mutation and remarkable diffuse round/spindle cell morphology. The tumors occurred in cervix (n = 1), and uterine corpus (n = 2). The patient ages were 30, 37 and 59 years with tumor size of 8.8, 10 and 8.6 cm, respectively. Morphologically all three tumors were characterized by distinct spindle/round cell morphology and various amounts of neuroectodermal differentiation (yolk sac-like tubules, blastomatous areas and rosette formation). Other morphologic features of DICER1-sarcoma reported in the literature including cambium layer, focal or diffuse anaplasia, solid and cystic architecture, and chondroid/osteoid areas were absent. All three sarcomas were positive for SALL4 and had variable neuroendocrine marker expression. Whole genome methylation analysis was performed on one of the uterine sarcomas, which clustered the tumor with embryonal tumor with multilayered rosettes. Follow up information was available on all three cases. Two patients were alive with no evidence of disease 13 and 14 months post operation, while one patient had imaging evidence of local recurrence 4 months post operation. In summary, we describe three unique DICER1-sarcomas and expand the phenotypic spectrum of this emerging entity, particularly with GYN-tract origin.

2.
Vet Pathol ; : 3009858241269877, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140425

RESUMEN

Rosettes and pseudorosettes are morphologic cell arrangements found in many neuroepithelial neoplasms in human medicine, including embryonal nervous system tumors (neuroblastoma, medulloblastoma, pineoblastoma, and retinoblastoma), non-embryonal nervous system tumors (ependymoma, astrocytoma, oligodendroglioma, and choroid plexus tumors), and other extraneural neuroepithelial neoplasms. Although these structures are also described in neuroepithelial neoplasms of domestic animals, their frequency is still poorly characterized or inconsistently documented in veterinary medicine. Furthermore, rosettes and pseudorosettes need to be interpreted with caution and within a clinical and pathologic context and should not be solely relied upon for diagnostic confirmation of a particular neoplasm. Here, we review the morphologic features and frequency of the most common types of rosettes and pseudorosettes described in neuroepithelial neoplasms of domestic animals, focusing primarily on those occurring in the nervous system and closely associated tissues.

3.
J Pak Med Assoc ; 74(7): 1370-1373, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39028075

RESUMEN

Olfactory neuroblastoma is a rare malignant tumour arising from the olfactory nerve and extending into the nasal cavity. In this case report, the case of a 42-year-old male is presented. The patient had a two-month history of progressive nasal blockage and episodes of epistaxis. No complaint of anosmia or facial pain was reported. All the necessary examinations were performed. Upon investigation, the CT scan and MRI showed a polypoid mass involving the right maxillary sinus, eroding the medial wall and expanding into the osteo-meatal complex. The diagnosis of olfactory neuroblastoma was confirmed through histopathological examination and further validated by immunohistochemistry as it was positive for synaptophysin, chromogranin, gamma enolase, and neurofilament. On staging, the tumour was Kadish B. The mass was excised by lateral rhinotomy. The patient was kept on radiotherapy and was free from recurrence upon follow-up 10 months later. It was concluded that based on the analysis of findings related to olfactory neuroblastomas, clinicians should contemplate the possibility of an ONB when radiographic images depict a dumbbell-shaped mass within the nasal cavity, accompanied by peritumoural cysts. Using a multimodal treatment approach is advisable.


Asunto(s)
Estesioneuroblastoma Olfatorio , Cavidad Nasal , Neoplasias Nasales , Humanos , Masculino , Adulto , Neoplasias Nasales/diagnóstico , Neoplasias Nasales/patología , Estesioneuroblastoma Olfatorio/diagnóstico , Estesioneuroblastoma Olfatorio/patología , Estesioneuroblastoma Olfatorio/diagnóstico por imagen , Cavidad Nasal/patología , Cavidad Nasal/diagnóstico por imagen , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
4.
Pathologica ; 116(3): 170-175, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38979591

RESUMEN

Embryonal tumors with multilayered rosettes (ETMR) are highly aggressive and therapy-resistant pediatric central nervous system (CNS) tumors that have three histological patters: embryonal tumor with abundant neuropil and true rosettes, ependymoblastoma, and medulloepithelioma. We present a case of ETMR in an 18-year-old woman with DICER1 syndrome. This report confirms the important role of DNA-methylation analysis in the classification of CNS embryonal tumors and the importance of investigating somatic and germline DICER1 mutations in all CNS embryonal tumors.


Asunto(s)
ARN Helicasas DEAD-box , Neoplasias de Células Germinales y Embrionarias , Ribonucleasa III , Humanos , Femenino , Ribonucleasa III/genética , ARN Helicasas DEAD-box/genética , Adolescente , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/patología , Metilación de ADN
5.
Childs Nerv Syst ; 40(9): 2685-2696, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38802706

RESUMEN

PURPOSE: Genetic mutations stand as pivotal factors leading to the occurrence of embryonal tumor with multilayered rosettes (ETMR). This study aims to identify improved treatment approaches by unraveling the genetic drivers and immune infiltration in ETMR. METHODS: Two siblings with ETMR, treated at the General Hospital of Ningxia Medical University, were enrolled. Diagnosis involved MRI, Hematoxylin and Eosin (HE), and immunohistochemical (IHC) staining. Differentially expressed genes (DEGs) in ETMR were identified using GSE122077 and GSE14296 datasets. GO and KEGG analyses were used to determine ETMR-related pathways. Whole exome sequencing (WES) was utilized to annotate genetic variations in ETMR. Core genes, identified by protein-protein interaction (PPI), formed a diagnostic model evaluated by Logistic Regression. Single-sample Gene Set Enrichment Analysis (ssGSEA) assessed immune infiltration in ETMR, examining correlations between immune cells and core genes. RESULTS: Two siblings were diagnosed with ETMR. In ETMR, 135 DEGs were identified, of which 25 genes were annotated with 28 mutation sites. Moreover, ETMR-related pathways included cell cycle, synaptic functions, and neurodegeneration. Three ETMR-related core genes (ALB, PSMD1, and PAK2) were screened by protein-protein interaction (PPI). The diagnostic model constructed using these genes demonstrated an AUC value of 0.901 (95% CI: 0.811-0.991) in the training set, indicating accurate predictions in ETMR. Enhanced ssGSEA scores for 16 immune cells in ETMR tissues suggested a strong immune response. CONCLUSION: This study identifies diagnostic models associated with three core variant genes (ALB, PSMD1, PAK2) and enhanced immune cell activity in ETMR. It reveals crucial genetic features and significant immune responses in ETMR.


Asunto(s)
Mutación , Neoplasias de Células Germinales y Embrionarias , Humanos , Mutación/genética , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/inmunología , Masculino , Femenino , Niño , Secuenciación del Exoma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Hermanos
6.
Neuro Oncol ; 26(5): 935-949, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38158710

RESUMEN

BACKGROUND: Embryonal tumors with multilayered rosettes (ETMR) are rare malignant embryonal brain tumors. The prognosis of ETMR is poor and novel therapeutic approaches are desperately needed. Comprehension of ETMR tumor biology is currently based on only few previous molecular studies, which mainly focused on the analyses of nucleic acids. In this study, we explored integrated ETMR proteomics. METHODS: Using mass spectrometry, proteome data were acquired from 16 ETMR and the ETMR cell line BT183. Proteome data were integrated with case-matched global DNA methylation data, publicly available transcriptome data, and proteome data of further embryonal and pediatric brain tumors. RESULTS: Proteome-based cluster analyses grouped ETMR samples according to histomorphology, separating neuropil-rich tumors with neuronal signatures from primitive tumors with signatures relating to stemness and chromosome organization. Integrated proteomics showcased that ETMR and BT183 cells harbor proteasome regulatory proteins in abundance, implicating their strong dependency on the proteasome machinery to safeguard proteostasis. Indeed, in vitro assays using BT183 highlighted that ETMR tumor cells are highly vulnerable toward treatment with the CNS penetrant proteasome inhibitor Marizomib. CONCLUSIONS: In summary, histomorphology stipulates the proteome signatures of ETMR, and proteasome regulatory proteins are pervasively abundant in these tumors. As validated in vitro, proteasome inhibition poses a promising therapeutic option in ETMR.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de Células Germinales y Embrionarias , Complejo de la Endopetidasa Proteasomal , Proteómica , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteómica/métodos , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Proteoma/metabolismo , Proteoma/análisis , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Inhibidores de Proteasoma/farmacología , Metilación de ADN
7.
Plants (Basel) ; 12(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38068625

RESUMEN

The art of the Achaemenid Empire flourished in Ancient Persia from the 6th to 4th centuries BCE, and featured stone-carved monumental structures adorned with recurring zoological and floral patterns. Such representations clearly had a symbolic meaning intimately connected to religious expression and the will of deities. Considering the lack of any comprehensive analysis of botanical features, we investigate the recurring plant patterns and the variety of plants depicted. An analysis of the documentation referring mainly to monuments in the two main capitals of Darius I, Persepolis and Susa, showed the presence of certain repetitive elements, such as the so-called rosettes (composed variously of Asteraceae capitula and Nymphaea flowers), palms (Phoenix dactylifera, the tree of life), pines, flowers or bunches and metamorphic elements. Some plants are described in this paper for the first time in the context of Persian iconography, such as Mandragora officinalis in offering scenes as a symbol of fertility and protection against evil spirits, Pinus brutia var. eldarica as a symbol of immortality and elevation to the gods, and the capitula of Matricaria/Leucanthemum as solar symbols. Further interesting elements include cf. Myrtus communis in some crowns and probably cf. Ephedra sp. in offering scenes. Achaemenid art was deeply influenced by the Zoroastrian religion of ancient Persia with its great attention to nature as well as by the nearby civilizations of the Mesopotamian area and Egypt. Most elements were also associated with psychotropic or medicinal attributes, which contributed to their position as symbols of power.

8.
Dermatol Reports ; 15(3): 9696, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37908606

RESUMEN

Granuloma faciale (GF) is a rare benign chronic inflammatory dermatosis often difficult to distinguish clinically from other diseases, both inflammatory and neoplastic. Dermoscopy can be a helpful diagnostic tool and indeed several dermoscopic criteria observed in GF have been described in literature. We present two patients affected by GF in which we have observed rosettes.

9.
Neuropathology ; 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37920133

RESUMEN

Embryonal tumors with multilayered rosettes (ETMRs) are aggressive central nervous system (CNS) tumors that usually occur in young children. Here, we describe the first incidence of ETMR in an adult patient that also originated in the novel location of the internal auditory canal (IAC). The 36-year-old patient initially presented with unsteadiness, diplopia, and tinnitus. The tumor in the IAC was discovered on brain magnetic resonance imaging, and gross total resection was performed followed by pathological and molecular diagnosis. The patient received whole brain and spinal cord radiotherapy after an intracranial recurrence and adjuvant chemotherapy consisting of four cycles of ifosfamide, cisplatin, and etoposide. Progression was rapid; however, the patient survived for 22 months after diagnosis before succumbing to the disease. Molecular investigation revealed a DICER1 mutation at exon 25, and methylation classification categorized the tumor as ETMR, non-C19MC-altered. This case underscores the diverse possible presentations of ETMR, DICER1-mutated and the importance of molecular techniques to characterize and promptly treat atypical ETMR.

11.
Front Cell Dev Biol ; 11: 1134091, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37635866

RESUMEN

Neural rosettes develop from the self-organization of differentiating human pluripotent stem cells. This process mimics the emergence of the embryonic central nervous system primordium, i.e., the neural tube, whose formation is under close investigation as errors during such process result in severe diseases like spina bifida and anencephaly. While neural tube formation is recognized as an example of self-organization, we still do not understand the fundamental mechanisms guiding the process. Here, we discuss the different theoretical frameworks that have been proposed to explain self-organization in morphogenesis. We show that an explanation based exclusively on stem cell differentiation cannot describe the emergence of spatial organization, and an explanation based on patterning models cannot explain how different groups of cells can collectively migrate and produce the mechanical transformations required to generate the neural tube. We conclude that neural rosette development is a relevant experimental 2D in-vitro model of morphogenesis because it is a multi-scale self-organization process that involves both cell differentiation and tissue development. Ultimately, to understand rosette formation, we first need to fully understand the complex interplay between growth, migration, cytoarchitecture organization, and cell type evolution.

12.
EMBO Rep ; 24(9): e57181, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37522754

RESUMEN

Hepatocytes form bile canaliculi that dynamically respond to the signalling activity of bile acids and bile flow. Little is known about their responses to intraluminal pressure. During embryonic development, hepatocytes assemble apical bulkheads that increase the canalicular resistance to intraluminal pressure. Here, we investigate whether they also protect bile canaliculi against elevated pressure upon impaired bile flow in adult liver. Apical bulkheads accumulate upon bile flow obstruction in mouse models and patients with primary sclerosing cholangitis (PSC). Their loss under these conditions leads to abnormally dilated canaliculi, resembling liver cell rosettes described in other hepatic diseases. 3D reconstruction reveals that these structures are sections of cysts and tubes formed by hepatocytes. Mathematical modelling establishes that they positively correlate with canalicular pressure and occur in early PSC stages. Using primary hepatocytes and 3D organoids, we demonstrate that excessive canalicular pressure causes the loss of apical bulkheads and formation of rosettes. Our results suggest that apical bulkheads are a protective mechanism of hepatocytes against impaired bile flow, highlighting the role of canalicular pressure in liver diseases.


Asunto(s)
Bilis , Hepatopatías , Ratones , Animales , Hígado , Canalículos Biliares , Hepatocitos
13.
Adv Exp Med Biol ; 1405: 225-252, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37452940

RESUMEN

The 2016 WHO classification of tumors of the central nervous system affected importantly the group of CNS embryonal tumors. Molecular analysis on methylome, genome, and transcriptome levels allowed better classification, identification of specific molecular hallmarks of the different subtypes of CNS embryonal tumors, and their more precise diagnosis. Routine application of appropriate molecular testing and standardized reporting are of pivotal importance for adequate prognosis and treatment, but also for epidemiology studies and search for efficient targeted therapies. As a result of this approach, the term primitive neuroectodermal tumor-PNET was removed and a new clinic-pathological entity was introduced-Embryonal tumor with multilayered rosettes (ETMR). The group of CNS embryonal tumors include also medulloblastoma, medulloepithelioma, CNS neuroblastoma, CNS ganglioneuroblastoma, atypical teratoid/rhabdoid tumor (ATRT) and their subtypes. This chapter will focus mainly on ETMR and ATRT. Embryonal tumors with multilayered rosettes and the atypical teratoid/rhabdoid tumors are undifferentiated or poorly differentiated tumors of the nervous system that originate from primitive brain cells, develop exclusively in childhood or adolescence, and are characterized by a high degree of malignancy, aggressive evolution and a tendency to metastasize to the cerebrospinal fluid. Their clinical presentation is similar to other malignant, intracranial, neoplastic lesions and depends mainly on the localization of the tumor, the rise of the intracranial pressure, and eventually the obstruction of the cerebrospinal fluid pathways. The MRI image characteristics of these tumors are largely overlappingintra-axial, hypercellular, heterogeneous tumors, frequently with intratumoral necrosis and/or hemorrhages. Treatment options for ETMR and ATRT are very restricted. Surgery can seldom achieve radical excision. The rarity of the disease hampers the establishment of a chemotherapy protocol and the usual age of the patients limits severely the application of radiotherapy as a therapeutic option. Consequently, the prognosis of these undifferentiated, malignant, aggressive tumors remains dismal with a 5-year survival between 0 and 30%.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Neoplasias Cerebelosas , Neoplasias de Células Germinales y Embrionarias , Tumores Neuroectodérmicos Primitivos , Tumor Rabdoide , Adolescente , Humanos , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/genética , Tumor Rabdoide/terapia , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/terapia , Neoplasias de Células Germinales y Embrionarias/diagnóstico , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/terapia , Neoplasias Encefálicas/patología , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/patología
14.
Adv Exp Med Biol ; 1405: 405-420, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37452947

RESUMEN

Embryonal tumors (ETs) of the central nervous system (CNS) comprise a large heterogeneous group of highly malignant tumors that predominantly affect children and adolescents. Currently, the neoplasms classified as ET are the medulloblastoma (MB), embryonal tumors with multilayered rosettes (ETMR), medulloepithelioma (ME), CNS neuroblastoma (NB), CNS ganglioneuroblastoma (GNB), atypical teratoid/rhabdoid tumors (AT/RT), and CNS embryonal tumors with rhabdoid features. All these tumors are classified as malignant-grade IV neoplasms, and the prognosis of patients with these neoplasms is very poor. Currently, except for the histological classification of MB, the recently utilized WHO classification accepts a novel molecular classification of MBs into four distinct molecular subgroups: wingless/integrated (WNT)-activated, sonic hedgehog (Shh), and the numerical Group3 and Group 4. The combination of both histological and genetic classifications has substantial prognostic significance, and patients are categorized as low risk with over 90% survival, the standard risk with 75-90% survival, high risk with 50-75% survival, and very high risk with survival rate lower than 50%. Children under three years are predominantly affected by AT/RT and represent about 20% of all CNS tumors in this age group. AT/RT is typically located in the posterior fossa (mainly in cerebellopontine angle) in 50-60% of the cases. The pathogenesis of this neoplasm is strongly associated with loss of function of the SMARCB1 (INI1, hSNF5) gene located at the 22q11.23 chromosome, or very rarely with alterations in (SMARCA4) BRG1 gene. The cells of this neoplasm resemble those of other neuronal tumors, and hence, immunochemistry markers have been utilized, such as smooth muscle actin, epithelial membrane antigen, vimentin, and lately antibodies for INI1. ETMRs are characterized by the presence of ependymoblastic rosettes formed by undifferentiated neuroepithelial cells and neuropil. The tumorigenesis of ETMRs is strongly related to the amplification of the pluripotency factor Chr19q13.41 miRNA cluster (C19MC) present in around 90% of the cases. Additionally, the expression of LIN28A is a highly sensitive and specific marker of ETMR diagnosis, as it is overexpressed in almost all cases of ETMR and is related to poor patient outcomes. The treatment of patients with ETs includes a combination of surgical resection, radiotherapy (focal or craniospinal), and chemotherapeutic agents. Currently, there is a trend to reduce the dose of craniospinal irradiation in the treatment of low-risk MBs. Novel targeted therapies are expected in the treatment of patients with MBs due to the identification of the main driver genes. Survival rates vary between ET types and their subtypes, with ganglioneuroblastoma having over 95% 5-year survival rate, while ATRT is probably linked with the worst prognosis with a 30% 5-year survival rate.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Cerebelosas , Ganglioneuroblastoma , Meduloblastoma , Neoplasias de Células Germinales y Embrionarias , Tumores Neuroectodérmicos Primitivos , Tumor Rabdoide , Neoplasias de la Médula Espinal , Niño , Adolescente , Humanos , Preescolar , Proteínas Hedgehog/metabolismo , Encéfalo/metabolismo , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/patología , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/genética , Tumor Rabdoide/terapia , Neoplasias Encefálicas/patología , ADN Helicasas/metabolismo , Proteínas Nucleares/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
15.
Virchows Arch ; 483(2): 255-260, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37270432

RESUMEN

Classic Hodgkin lymphoma (CHL) harbors a small number of Hodgkin-Reed-Sternberg (HRS) cells scattered among numerous lymphocytes. HRS cells are surrounded by distinct CD4+ T cells in a rosette-like manner. These CD4+ T cell rosettes play an important role in the tumor microenvironment (TME) of CHL. To elucidate the interaction between HRS cells and CD4+ T cell rosettes, we completed digital spatial profiling to compare the gene expression profiles of CD4+ T cell rosettes and other CD4+ T cells separated from the HRS cells. Immune checkpoint molecules including OX40, programed cell death-1 (PD-1), and cytotoxic T lymphocyte associated protein 4 (CTLA-4) expression was higher in CD4+ T cell rosettes compared to other CD4+ T cells. Immunohistochemistry confirmed variable PD-1, CTLA-4, and OX40 expression in the CD4+ T cell rosettes. This study introduced a new pathological approach to study the CHL TME, and provided deeper insight into CD4+ T cells in CHL.


Asunto(s)
Enfermedad de Hodgkin , Humanos , Enfermedad de Hodgkin/patología , Linfocitos T/metabolismo , Antígeno CTLA-4 , Receptor de Muerte Celular Programada 1/metabolismo , Células de Reed-Sternberg/metabolismo , Linfocitos T CD4-Positivos , Microambiente Tumoral
16.
Materials (Basel) ; 16(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37176186

RESUMEN

Natural convection is present in all liquid alloys whereas forced convection may be applied as the method to improve material properties. To understand the effect of forced convection, the solidification in simple cylindrical samples was studied using a rotating magnetic field with a low cooling rate and low temperature gradient. The composition of Al-Si-Fe alloys was chosen to enable independent growth or joint growth of occurring α-Al, ß-Al5FeSi, δ-AlFeSi_T4 phases and Si crystals and analysis of structure modifications. Stirring produced rosettes instead of equiaxed dendrites, which altered the secondary dendrite arm spacing and the specific surface of α-Al and also modified ß-Al5FeSi. The melt flow caused a modification of iron rich δ-AlFeSi_T4 phases and gathered them inside the sample of the ß/Si alloy, where δ together with Si were the first precipitating phases. The separation of δ and ß phases and Si crystals was found by their joint growth along the monovariant line. A reduction in the amount of Si crystals and the formation of a thin Si-rich layer outside the sample was observed in the hypereutectic alloy. The separation and reduction in iron-rich phases may play a role in the removal of Fe from Al-Si alloys, and the control of Si may be applied in materials for the solar photovoltaic industry.

17.
Cancer Rep (Hoboken) ; 6(5): e1812, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36965133

RESUMEN

BACKGROUND: Embryonal tumor with multilayered rosettes (ETMR) is a deadly grade IV pediatric brain tumor. Despite an intensive multimodal treatment approach that includes surgical resection, high-dose chemotherapy, and radiotherapy, the progression-free survival at 5 years is less than 30%. CASE: We report a case of long-term survival in a 5-month old female with a large mass in the posterior fossa, diagnosed as ETMR, which subsequently underwent treatment-induced maturation. Prior to chemotherapy, histopathology revealed an abundance of highly proliferative, undifferentiated cells and multilayered rosette structures. Conversely, post-treatment histopathology revealed cell populations that differentiated into neuronal and ganglionic phenotypes. At 5-year follow-up, the patient remains progression-free. CONCLUSION: This finding contributes to the few reports to date of post-treatment differentiation/maturation of ETMR cell populations, with an implication for less cytotoxic therapeutic interventions aimed at differentiation.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Neoplasias de Células Germinales y Embrionarias , Tumores Neuroectodérmicos Primitivos , Humanos , Femenino , Neoplasias de Células Germinales y Embrionarias/terapia , Neoplasias Encefálicas/patología , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/patología , Tumores Neuroectodérmicos Primitivos/terapia
18.
Brain Sci ; 13(2)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36831872

RESUMEN

Transplantation of immature dopaminergic neurons or neural precursors derived from embryonic stem cells (ESCs) into the substantia nigra pars compacta (SNpc) is a potential therapeutic approach for functional restitution of the nigrostriatal pathway in Parkinson's disease (PD). However, further studies are needed to understand the effects of the local microenvironment on the transplanted cells to improve survival and specific differentiation in situ. We have previously reported that the adult SNpc sustains a neurogenic microenvironment. Non-neuralized embryoid body cells (EBCs) from mouse ESCs (mESCs) overexpressing the dopaminergic transcription factor Lmx1a gave rise to many tyrosine hydroxylase (Th+) cells in the intact and damaged adult SNpc, although only for a short-term period. Here, we extended our study by transplanting EBCs from genetically engineered naive human ESC (hESC), overexpressing the dopaminergic transcription factors LMX1A, FOXA2, and OTX2 (hESC-LFO), in the SNpc. Unexpectedly, no graft survival was observed in wild-type hESC EBCs transplants, whereas hESC-LFO EBCs showed viability in the SNpc. Interestingly, neural rosettes, a developmental hallmark of neuroepithelial tissue, emerged at 7- and 15-days post-transplantation (dpt) from the hESC-LFO EBCs. Neural rosettes expressed specification dopaminergic markers (Lmx1a, Otx2), which gave rise to several Th+ cells at 30 dpt. Our results suggest that the SNpc enables the robust initiation of neural differentiation of transplanted human EBCs prompted to differentiate toward the midbrain dopaminergic phenotype.

19.
Cells ; 11(22)2022 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-36428968

RESUMEN

Intrauterine infections during pregnancy by herpes simplex virus (HSV) can cause significant neurodevelopmental deficits in the unborn/newborn, but clinical studies of pathogenesis are challenging, and while animal models can model some aspects of disease, in vitro studies of human neural cells provide a critical platform for more mechanistic studies. We utilized a reductionist approach to model neurodevelopmental outcomes of HSV-1 infection of neural rosettes, which represent the in vitro equivalent of differentiating neural tubes. Specifically, we employed early-stage brain organoids (ES-organoids) composed of human induced pluripotent stem cells (hiPSCs)-derived neural rosettes to investigate aspects of the potential neuropathological effects induced by the HSV-1 infections on neurodevelopment. To allow for the long-term differentiation of ES-organoids, viral infections were performed in the presence of the antiviral drug acyclovir (ACV). Despite the antiviral treatment, HSV-1 infection caused organizational changes in neural rosettes, loss of structural integrity of infected ES-organoids, and neuronal alterations. The inability of ACV to prevent neurodegeneration was associated with the generation of ACV-resistant mutants during the interaction of HSV-1 with differentiating neural precursor cells (NPCs). This study models the effects of HSV-1 infection on the neuronal differentiation of NPCs and suggests that this environment may allow for accelerated development of ACV-resistance.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Células Madre Pluripotentes Inducidas , Células-Madre Neurales , Animales , Recién Nacido , Humanos , Organoides , Aciclovir/farmacología , Aciclovir/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Encéfalo
20.
Front Oncol ; 12: 1001959, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36353532

RESUMEN

Objective: Embryonal tumors with multilayered rosettes (ETMRs) are a histologically heterogeneous entity and gather embryonal tumors with abundant neuropil and true rosettes (ETANTRs), ependymoblastoma, and medulloepithelioma. ETMRs are highly aggressive and associated with poorer clinical courses. However, cases of this entity are rare, and advances in molecular genetics and therapy are minor. The purpose of our study was to retrospectively analyze the clinical, pathological features, and prognostic factors of ETMRs. Methods: Our cohort consisted of 17 patients diagnosed with ETMRs in our hospital from 2018 to 2022, and two of them were lost to follow-up. Clinical data were retrieved, and immunohistochemistry and genetic analyses were performed. Results: Among 17 cases, 16 were ETANTRs, and one was medulloepithelioma. Morphologically, tumor cells of ETANTRs could transform into anaplasia and lose the biphasic architecture during tumor progression. Immunohistochemistry of LIN28A revealed positive expression in 17 cases, and the expression of LIN28A was more intense and diffuse in the recurrent lesions than in primaries. The increased N-MYC copy numbers were detected in the primary tumor and recurrence of patient 8. Moreover, the incidence of metastatic disease was 100% in patients aged > 4 years and 18% in the younger group. For patients receiving chemotherapy, the median overall survival time was 7.4 months, while that of those who didn't receive it was 1.2 months. Nevertheless, surgical approaches, radiotherapy, age at presentation, gender, tumor location, and metastatic status were not associated with independent prognosis. Conclusion: ETANTR might not present as the typical morphologies during tumor progression, so analyses of C19MC amplification and Lin28A antibody are indispensable for diagnosing ETMRs accurately. Children aged > 4 years tend to have a higher rate of metastasis in ETMRs. Chemotherapy is the only prognostic factor for ETMRs patients with a favorable prognosis. The biological nature and clinical patterns for recurrent diseases need to be further demonstrated to predict prognosis and guide treatment.

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