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1.
Cell Tissue Bank ; 22(3): 505-509, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33523332

RESUMEN

Research in neuroscience relies heavily upon postmortem human brain tissue. Cerebellar granular layer autolysis (GLA) is a surrogate marker for the quality of such tissue and suitability for molecular analysis. GLA is associated with reduced brain tissue pH. The aim of this study was to assess correlation of GLA with premortem systemic acid-base status. This is a retrospective study in which 62 consecutive adult autopsy cases were included. Sections of cerebellum were reviewed microscopically for presence of GLA. Autolysis was graded as negative, grade 1, grade 2, and grade 3. Medical records were reviewed for arterial blood gas analysis. Postmortem interval was recorded. 23 of 62 cases showed GLA. Of the 23 patients with autolysis, 22 were acidotic and 1 was alkalotic. Of these 23 cases, 15 had metabolic acidosis, 4 had respiratory acidosis, 3 had combined acidosis and 1 had respiratory alkalosis. There was no statistically significant difference in postmortem interval between the two groups. 10 cases with grade 3 autolysis had mean pH of 7.13, 7 cases with grade 2 autolysis had mean pH of 7.23 and in 6 cases with grade 1 autolysis the mean pH was 7.2. Overall, the mean pH in patients with GLA was 7.19, and in the non-autolytic cases the mean pH was 7.28 (P < 0.05). There was no correlation between the degree of acidosis and severity of autolysis. GLA is associated with premortem systemic acidosis, and premortem systemic alkalosis is associated with the absence of GLA. Premortem acid-base status may serve as an additional quality indicator for assessment of tissue for research.


Asunto(s)
Encéfalo , Cerebelo , Adulto , Autólisis , Autopsia , Humanos , Concentración de Iones de Hidrógeno , Estudios Retrospectivos
2.
Compr Rev Food Sci Food Saf ; 19(4): 2110-2138, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33337103

RESUMEN

There is a need to develop food processing technologies with enhanced antimicrobial capacity against foodborne pathogens. While considering the challenges of adequate inactivation of pathogenic microorganisms in different food matrices, the emerging technologies are also expected to be sustainable and have a minimum impact on food quality and nutrients. Synergistic combinations of food processing technologies and food-grade compounds have a great potential to address these needs. During these combined treatments, food processes directly or indirectly interact with added chemicals, intensifying the overall antimicrobial effect. This review provides an overview of the combinations of different thermal or nonthermal processes with a variety of food-grade compounds that show synergistic antimicrobial effect against pathogenic microorganisms in foods and model systems. Further, we summarize the underlying mechanisms for representative combined treatments that are responsible for the enhanced microbial inactivation. Finally, regulatory issues and challenges for further development and technical transfer of these new approaches at the industrial level are also discussed.


Asunto(s)
Manipulación de Alimentos/métodos , Microbiología de Alimentos/métodos , Conservantes de Alimentos , Calidad de los Alimentos , Viabilidad Microbiana
3.
Pediatr Neurosurg ; 53(1): 59-63, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29131126

RESUMEN

Diffuse midline glioma, H3-K27M mutant (DMG-K27M) is a newly described, molecularly distinct infiltrative glioma that almost exclusively arises in midline CNS structures, including the brain stem, especially the pons, as well as the thalamus and spinal cord with rare examples seen in the cerebellum, third ventricle, and hypothalamus. To our knowledge, only 1 case of a molecularly confirmed DMG-K27M arising in the pineal region has been previously reported. We present the second occurrence of a tissue-confirmed DMG-K27M of the pineal region, which, to our knowledge, is the first case reported in a child and the first case with documented preoperative MRI. This case, in addition to a prior report described in an adult, defines the lower end of a broad age range of DMG-K27M onset (12-65 years) and establishes the pineal gland as a bona fide site of origin for this newly codified midline glioma.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagen , Glioma/genética , Mutación/genética , Glándula Pineal/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Niño , Femenino , Glioma/cirugía , Humanos , Glándula Pineal/cirugía
5.
Arch Pathol Lab Med ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38452801

RESUMEN

CONTEXT.­: Autopsies performed on COVID-19 patients have provided critical information about SARS-CoV-2's tropism, mechanisms of tissue injury, and the spectrum of disease. OBJECTIVE.­: To provide an updated database of postmortem disease in COVID-19 patients, assess relationships among clinical and pathologic variables, evaluate the accuracy of death certification, and correlate disease variables to causes of death. DESIGN.­: The 272 postmortem examinations reported in this paper were submitted by 14 pathologists from 9 medical or forensic institutions across the United States. The study spans the eras of the 3 principal COVID-19 strains and incorporates surveyed demographic, clinical, and postmortem data from decedents infected with SARS-CoV-2, including primary and contributing causes of death. It is the largest database of its kind to date. RESULTS.­: Demographics of the decedents reported here correspond well to national statistics. Primary causes of death as determined by autopsy and official death certificates were significantly correlated. When specifically cited disease conditions found at autopsy were correlated with COVID-19 versus non-COVID-19 death, only lung findings characteristic of SARS-CoV-2 infection or the absence of lung findings were significantly associated. CONCLUSIONS.­: Changes in hospitalization and disease likely stem from longer lifespans after COVID-19 diagnosis and alteration in treatment approaches. Although Omicron variants preferentially replicate in the upper airways, autopsied patients who died of COVID-19 in that time period showed the same lung damage as earlier decedents. Most importantly, findings suggest that there are still unelucidated risk factors for death from COVID-19 including possibly genetic susceptibility.

6.
Nat Commun ; 15(1): 6707, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112464

RESUMEN

Sacituzumab Govitecan (SG) is an antibody-drug conjugate that has demonstrated efficacy in patients with TROP-2 expressing epithelial cancers. In a xenograft model of intracranial breast cancer, SG inhibited tumor growth and increased mouse survival. We conducted a prospective window-of-opportunity trial (NCT03995706) at the University of Texas Health Science Center at San Antonio to examine the intra-tumoral concentrations and intracranial activity of SG in patients undergoing craniotomy for breast cancer with brain metastases (BCBM) or recurrent glioblastoma (rGBM). We enrolled 25 patients aged ≥18 years diagnosed with BCBM and rGBM to receive a single intravenous dose of SG at 10 mg/kg given one day before resection and continued on days 1 and 8 of 21-day cycles following recovery. The PFS was 8 months and 2 months for BCBM and rGBM cohorts, respectively. The OS was 35.2 months and 9.5 months, respectively. Grade≥3 AE included neutropenia (28%), hypokalemia (8%), seizure (8%), thromboembolic event (8%), urinary tract infection (8%) and muscle weakness of the lower limb (8%). In post-surgical tissue, the median total SN-38 was 249.8 ng/g for BCBM and 104.5 ng/g for rGBM, thus fulfilling the primary endpoint. Biomarker analysis suggests delivery of payload by direct release at target site and that hypoxic changes do not drive indirect release. Secondary endpoint of OS was 35.2 months for the BCBM cohort and 9.5 months for rGBM. Non-planned exploratory endpoint of ORR was 38% for BCBM and 29%, respectively. Exploratory endpoint of Trop-2 expression was observed in 100% of BCBM and 78% of rGBM tumors. In conclusion, SG was found to be well tolerated with adequate penetration into intracranial tumors and promising preliminary activity within the CNS. Trial Registration: Trial (NCT03995706) enrolled at Clinical Trials.gov as Neuro/Sacituzumab Govitecan/Breast Brain Metastasis/Glioblastoma/Ph 0: https://clinicaltrials.gov/study/NCT03995706?cond=NCT03995706 .


Asunto(s)
Anticuerpos Monoclonales Humanizados , Neoplasias Encefálicas , Neoplasias de la Mama , Glioblastoma , Inmunoconjugados , Recurrencia Local de Neoplasia , Humanos , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Persona de Mediana Edad , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Adulto , Anciano , Inmunoconjugados/uso terapéutico , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Estudios Prospectivos , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Antígenos de Neoplasias/metabolismo , Moléculas de Adhesión Celular/metabolismo
7.
Neuro Oncol ; 25(3): 459-470, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35862252

RESUMEN

BACKGROUND: The loss of neurogenic tumor suppressor microRNAs miR-124, miR-128, and miR-137 is associated with glioblastoma's undifferentiated state. Most of their impact comes via the repression of a network of oncogenic transcription factors. We conducted a high-throughput functional siRNA screen in glioblastoma cells and identify E74 like ETS transcription factor 4 (ELF4) as the leading contributor to oncogenic phenotypes. METHODS: In vitro and in vivo assays were used to assess ELF4 impact on cancer phenotypes. We characterized ELF4's mechanism of action via genomic and lipidomic analyses. A MAPK reporter assay verified ELF4's impact on MAPK signaling, and qRT-PCR and western blotting were used to corroborate ELF4 regulatory role on most relevant target genes. RESULTS: ELF4 knockdown resulted in significant proliferation delay and apoptosis in GBM cells and long-term growth delay and morphological changes in glioma stem cells (GSCs). Transcriptomic analyses revealed that ELF4 controls two interlinked pathways: 1) Receptor tyrosine kinase signaling and 2) Lipid dynamics. ELF4 modulation directly affected receptor tyrosine kinase (RTK) signaling, as mitogen-activated protein kinase (MAPK) activity was dependent upon ELF4 levels. Furthermore, shotgun lipidomics revealed that ELF4 depletion disrupted several phospholipid classes, highlighting ELF4's importance in lipid homeostasis. CONCLUSIONS: We found that ELF4 is critical for the GBM cell identity by controlling genes of two dependent pathways: RTK signaling (SRC, PTK2B, and TNK2) and lipid dynamics (LRP1, APOE, ABCA7, PLA2G6, and PITPNM2). Our data suggest that targeting these two pathways simultaneously may be therapeutically beneficial to GBM patients.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , MicroARNs , Humanos , Factores de Transcripción/genética , Glioblastoma/patología , MicroARNs/genética , Proteínas Tirosina Quinasas Receptoras/genética , Regulación Neoplásica de la Expresión Génica , Lípidos , Proliferación Celular , Línea Celular Tumoral , Neoplasias Encefálicas/patología , Proteínas de Unión al ADN/genética , Proteínas Tirosina Quinasas/metabolismo
8.
Neuro Oncol ; 25(7): 1249-1261, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-36652263

RESUMEN

BACKGROUND: Efficient DNA repair in response to standard chemo and radiation therapies often contributes to glioblastoma (GBM) therapy resistance. Understanding the mechanisms of therapy resistance and identifying the drugs that enhance the therapeutic efficacy of standard therapies may extend the survival of GBM patients. In this study, we investigated the role of KDM1A/LSD1 in DNA double-strand break (DSB) repair and a combination of KDM1A inhibitor and temozolomide (TMZ) in vitro and in vivo using patient-derived glioma stem cells (GSCs). METHODS: Brain bioavailability of the KDM1A inhibitor (NCD38) was established using LS-MS/MS. The effect of a combination of KDM1A knockdown or inhibition with TMZ was studied using cell viability and self-renewal assays. Mechanistic studies were conducted using CUT&Tag-seq, RNA-seq, RT-qPCR, western blot, homologous recombination (HR) and non-homologous end joining (NHEJ) reporter, immunofluorescence, and comet assays. Orthotopic murine models were used to study efficacy in vivo. RESULTS: TCGA analysis showed KDM1A is highly expressed in TMZ-treated GBM patients. Knockdown or knockout or inhibition of KDM1A enhanced TMZ efficacy in reducing the viability and self-renewal of GSCs. Pharmacokinetic studies established that NCD38 readily crosses the blood-brain barrier. CUT&Tag-seq studies showed that KDM1A is enriched at the promoters of DNA repair genes and RNA-seq studies confirmed that KDM1A inhibition reduced their expression. Knockdown or inhibition of KDM1A attenuated HR and NHEJ-mediated DNA repair capacity and enhanced TMZ-mediated DNA damage. A combination of KDM1A knockdown or inhibition and TMZ treatment significantly enhanced the survival of tumor-bearing mice. CONCLUSIONS: Our results provide evidence that KDM1A inhibition sensitizes GBM to TMZ via attenuation of DNA DSB repair pathways.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Animales , Ratones , Temozolomida/farmacología , Temozolomida/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Lisina/genética , Lisina/farmacología , Lisina/uso terapéutico , Roturas del ADN de Doble Cadena , Espectrometría de Masas en Tándem , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Reparación del ADN , ADN/farmacología , ADN/uso terapéutico , Histona Demetilasas/genética , Histona Demetilasas/farmacología , Histona Demetilasas/uso terapéutico , Resistencia a Antineoplásicos , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Elife ; 122023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-37266578

RESUMEN

In embryonal rhabdomyosarcoma (ERMS) and generally in sarcomas, the role of wild-type and loss- or gain-of-function TP53 mutations remains largely undefined. Eliminating mutant or restoring wild-type p53 is challenging; nevertheless, understanding p53 variant effects on tumorigenesis remains central to realizing better treatment outcomes. In ERMS, >70% of patients retain wild-type TP53, yet mutations when present are associated with worse prognosis. Employing a kRASG12D-driven ERMS tumor model and tp53 null (tp53-/-) zebrafish, we define wild-type and patient-specific TP53 mutant effects on tumorigenesis. We demonstrate that tp53 is a major suppressor of tumorigenesis, where tp53 loss expands tumor initiation from <35% to >97% of animals. Characterizing three patient-specific alleles reveals that TP53C176F partially retains wild-type p53 apoptotic activity that can be exploited, whereas TP53P153Δ and TP53Y220C encode two structurally related proteins with gain-of-function effects that predispose to head musculature ERMS. TP53P153Δ unexpectedly also predisposes to hedgehog-expressing medulloblastomas in the kRASG12D-driven ERMS-model.


Asunto(s)
Neoplasias Cerebelosas , Rabdomiosarcoma Embrionario , Animales , Carcinogénesis , Mutación , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Rabdomiosarcoma Embrionario/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
10.
Medicine (Baltimore) ; 101(9): e28806, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35244038

RESUMEN

RATIONALE: Epstein-Barr virus-associated smooth muscle tumors (EBV-SMT) are rare, virally-induced malignancies that occur almost exclusively in immunocompromised individuals. We report a very rare case of a dura-based EBV-SMT with superimposed local cryptococcal infection. PATIENT CONCERNS: An adult male with a history of untreated acquired immunodeficiency syndrome presented to our hospital with worsening headaches, diarrhea, and diffuse myalgias. DIAGNOSES: Blood cultures were positive for methicillin-resistant Staphylococcus aureus and Cryptococcus neoformans serum antigen. Magnetic resonance imaging revealed 2 adjacent enhancing masses in the right temporal lobe, perilesional edema, and mass effect of the right lateral ventricle. Histological examination and immunohistochemical stains of the surgical specimen were consistent with EBV-SMT. Cryptococcus organisms were identified within the neoplasm. INTERVENTIONS: The patient underwent complete tumor resection, received an extended course of amphotericin and flucytosine, and was restarted on antiretroviral therapy. OUTCOMES: The patient was discharged from the hospital with no focal neurological deficits. LESSONS: Epstein-Barr virus associated smooth muscle tumors are rare malignancies that occur in immunocompromised patients. Prognosis is largely dependent on immune reconstitution and treatment of concomitant infections.


Asunto(s)
Cryptococcus neoformans/aislamiento & purificación , Infecciones por Virus de Epstein-Barr/patología , Herpesvirus Humano 4/aislamiento & purificación , Imagen por Resonancia Magnética/métodos , Tumor de Músculo Liso/patología , Sobreinfección , Lóbulo Temporal/diagnóstico por imagen , Adulto , Anfotericina B/uso terapéutico , Terapia Antirretroviral Altamente Activa , Infecciones por Virus de Epstein-Barr/complicaciones , Flucitosina/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Herpesvirus Humano 4/genética , Humanos , Huésped Inmunocomprometido , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Oportunistas , Tumor de Músculo Liso/virología
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