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1.
Neurotoxicology ; 91: 200-210, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35643325

RESUMEN

Diethylene glycol (DEG) is an organic compound that has been found as an adulterant in consumer products as a counterfeit glycerin. Diethylene glycol is metabolized to two primary metabolites: 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA), the latter shown to accumulate in the kidney and cause dose-dependent cell necrosis. DEG poisonings are characterized predominately by acute kidney injury (AKI) but have also produced delayed neurological sequelae such as sensorimotor neuropathy. To better understand these effects, Wistar-Han rats were orally administered a water control or doses of 4 g/kg-6 g/kg DEG every 12 or 24 h for 7 days, with kidney, brain, and spinal cord tissue collected for histopathological analysis. This dosing paradigm resulted in approximately 25 % of the DEG-treated animals developing AKI and also neurotoxicity (sensorimotor dysfunction and elevated cerebrospinal fluid (CSF) protein). Kidney pathology included a severe, diffuse acute kidney tubular necrosis predominantly affecting proximal convoluted tubules. Scattered birefringent crystals consistent with calcium oxalate monohydrate were also found in the proximal tubule of animals with AKI. Demyelination in the dorsal and lateral white matter regions of the cervical, thoracic, and lumbar areas of the spinal cord of a DEG-treated animal with AKI was documented, establishing the neuropathology in DEG-treated animals that developed neurotoxicity. There were significant changes in amino acid concentrations in the CSF that may reflect the neurotoxicity of DEG, specifically glutamate and glutamine, but with no ammonia change. These studies characterized the pathologic aspects of the neurotoxicity in a DEG repeat-dose model.


Asunto(s)
Lesión Renal Aguda , Síndromes de Neurotoxicidad , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/complicaciones , Lesión Renal Aguda/metabolismo , Animales , Glicoles de Etileno , Riñón/metabolismo , Riñón/patología , Síndromes de Neurotoxicidad/patología , Ratas , Ratas Wistar
2.
Am J Ophthalmol Case Rep ; 25: 101236, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34917855

RESUMEN

PURPOSE: To underscore the importance of histopathological evaluation in cases presenting with a constellation of unusual ocular inflammation and physical findings. OBSERVATION: A 51-year-old male, presented with a chief complaint of worsening visual field loss due to droopy eyelids two months post excision of a right upper eyelid squamous cell carcinoma. His past medical history included chronic edematous facial features, chronic sinusitis, unexplained peripheral neuropathy, and worsening fatigue. Pre-blepharoplasty work-up revealed mechanical ptosis from lid edema, madarosis, a concave nasal bridge, pancytopenia, and numerous burn marks due to inadvertent injuries. Bilateral blepharoplasty was performed, and the excised tissue submitted for histopathological evaluation that revealed non-caseating granulomatous perineural inflammation with numerous acid-fast bacilli in dermal layers and nerves. These findings prompted a diagnosis of lepromatous leprosy with suspected bone marrow involvement. The source of the infection was unknown. The blepharoplasty restored his visual fields and multi-drug therapy (MDT) improved his general health and wellbeing with concomitant reductions of pancytopenia, fatigue, and facial edema. CONCLUSIONS AND IMPORTANCE: Biopsy histopathology, in patients with longstanding ocular adnexal inflammation, can facilitate diagnosis and treatment. To the authors' knowledge, this is an unusual ocular leprosy presentation and represents the first leprosy case diagnosed via blepharoplasty.

3.
BMJ Case Rep ; 14(2)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33579799

RESUMEN

Ectopic or supernumerary parathyroid tissue has been generally described in the literature in cases found during workup for parathyroid adenoma. We present two unique cases of intratracheal parathyroid gland, a rare occurrence that has not yet been described in the literature. In both cases, the masses were found incidentally and showed no clinical or laboratory evidence of hyperparathyroidism. In both cases, surveillance was chosen as the method of treatment. We present this case series to increase awareness of this potential diagnosis.


Asunto(s)
Glándulas Paratiroides/diagnóstico por imagen , Glándulas Paratiroides/fisiopatología , Neoplasias de las Paratiroides/diagnóstico , Neoplasias de las Paratiroides/fisiopatología , Neoplasias de las Paratiroides/cirugía , Tráquea/diagnóstico por imagen , Tráquea/fisiopatología , Adulto , Anciano , Femenino , Humanos , Masculino , Resultado del Tratamiento
4.
BMJ Case Rep ; 13(12)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33298488

RESUMEN

This report describes the diagnosis and treatment of a patient with a rare primary facial nerve paraganglioma as well as a review of the current literature. A 60-year-old male patient presented to our clinic with a 4-month history of left-sided progressive facial paralysis House-Brackmann V. Biopsy taken during facial nerve (FN) decompression confirmed the diagnosis of paraganglioma. The left FN was sacrificed during resection of the mass and a 12-7 jump graft, using the left greater auricular nerve, was performed with acceptable outcomes. The rarity of these tumours does not discount their clinical importance or the necessity to include them in the differential when presented with unilateral FN paralysis. Investigation should begin with CT and MRI imaging to identify and localise the potential mass. Histologic confirmation requires tissue. While surveillance imaging is occasionally an option, often complete surgical resection of the mass and sacrifice of the nerve is necessary.


Asunto(s)
Neoplasias de los Nervios Craneales/diagnóstico , Enfermedades del Nervio Facial/diagnóstico , Paraganglioma/diagnóstico , Neoplasias de los Nervios Craneales/patología , Neoplasias de los Nervios Craneales/cirugía , Enfermedades del Nervio Facial/patología , Enfermedades del Nervio Facial/cirugía , Parálisis Facial/etiología , Pérdida Auditiva Sensorineural/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Paraganglioma/patología , Paraganglioma/cirugía , Tomografía Computarizada por Rayos X
6.
BMC Cancer ; 14: 57, 2014 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-24485087

RESUMEN

BACKGROUND: The HECT family ubiquitin ligase Smurf2 regulates cell polarity, migration, division, differentiation and death, by targeting diverse substrates that are critical for receptor signaling, cytoskeleton, chromatin remodeling and transcription. Recent studies suggest that Smurf2 functions as a tumor suppressor in mice. However, no inactivating mutation of SMURF2 has been reported in human, and information about Smurf2 expression in human cancer remains limited or complicated. Here we demonstrate that Smurf2 expression is downregulated in human breast cancer tissues, especially of the triple-negative subtype, and address the mechanism of Smurf2 downregulation in triple-negative breast cancer cells. METHODS: Human breast cancer tissues (47 samples expressing estrogen receptor (ER) and 43 samples with triple-negative status) were examined by immunohistochemistry for the expression of Smurf2. Ten widely-studied human breast cancer cell lines were examined for the expression of Smurf2. Furthermore, microRNA-mediated regulation of Smurf2 was investigated in triple-negative cancer cell lines. RESULTS: Immunohistochemical analysis showed that benign mammary epithelial cells expressed high levels of Smurf2, so did cells in ductal carcinomas in situ. In contrast, invasive ductal carcinomas showed focal or diffuse decrease in Smurf2 expression, which was observed more frequently in triple-negative tumors than in ER-positive tumors. Consistently, human triple-negative breast cancer cell lines such as BT549, MDA-MB-436, DU-4475 and MDA-MB-468 cells showed significantly lower expression of Smurf2 protein, compared to ER + or HER2+ cell lines. Studies using quantitative PCR and specific microRNA inhibitors indicated that increased expression of miR-15a, miR-15b, miR-16 and miR-128 was involved in Smurf2 downregulation in those triple-negative cancer cell lines, which have mutations in the retinoblastoma (RB) gene. Forced expression of RB increased levels of Smurf2 protein with concomitant decreases in the expression of the microRNAs. CONCLUSIONS: This study provides evidence of posttranscriptional downregulation of Smurf2 in triple-negative breast cancers, and demonstrates that the loss of RB function is involved in microRNA-mediated interference with Smurf2 translation. The new link from RB inactivation to Smurf2 downregulation is likely to play a role in malignant phenotypes of triple-negative breast cancer cells.


Asunto(s)
Carcinoma Ductal de Mama/enzimología , Carcinoma Intraductal no Infiltrante/enzimología , MicroARNs/metabolismo , Proteína de Retinoblastoma/metabolismo , Neoplasias de la Mama Triple Negativas/enzimología , Ubiquitina-Proteína Ligasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/genética , Carcinoma Intraductal no Infiltrante/patología , Línea Celular Tumoral , Regulación hacia Abajo , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Mutación , Fenotipo , Interferencia de ARN , Proteína de Retinoblastoma/genética , Transducción de Señal , Transfección , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Ubiquitina-Proteína Ligasas/genética
7.
World Neurosurg ; 79(2): 313-9.e1-10, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22120298

RESUMEN

BACKGROUND: This study sought to identify genes in nontypical meningiomas with gains in copy number (CN) that correlate with earlier age of onset, an indicator of aggressiveness. METHODS: Among 94 adult patients, 91 had 105 meningiomas that were histologically confirmed. World Health Organization grades I (typical), II (atypical), and III (anaplastic) were assigned to tumors in 76, 14, and 1 patient, respectively. Brain invasion indicated that two World Health Organization grade I meningiomas were biologically atypical. DNA from 15 invasive/atypical/anaplastic meningiomas and commercial normal DNA were analyzed with multiplex ligation dependent probe amplification. The CN ratios (fold differences from normal) for 78 genes were determined. The CN ratio was defined as [tumor CN]/[normal CN] for each gene to normalize results. RESULTS: Characteristic gene losses (CN ratio < 0.75) occurred in >50% of the invasive/atypical/anaplastic meningiomas at 22q11, 1p34.2, and 1p22.1 loci. Gains (CN ratio ≥ 2.0) occurred in each tumor for 2 or more of 19 genes. Each of the 19 genes' CN ratio was ≥ 2.0 in multiple tumors, and their collective sums (up to 49.1) correlated inversely with age (r = -0.72), minus an outlier. In patients ≤ 55 versus >55 years, 5 genes (BIRC2, BRAF, MET, NRAS, and PIK3CA) individually exhibited significantly higher CN ratios (P < 0.05) or a trend for them (P < 0.09), with corrections for multiple comparisons, and their sums correlated inversely with age (r = -0.74). CONCLUSIONS: Low levels of amplification for selected oncogenes in invasive/atypical/anaplastic meningiomas were higher in younger adults, with the CN gains potentially underlying biological aggressiveness associated with early tumor development.


Asunto(s)
Amplificación de Genes/genética , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Meningioma/genética , Meningioma/patología , Oncogenes/genética , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Dosificación de Gen , Humanos , Masculino , Neoplasias Meníngeas/epidemiología , Meningioma/epidemiología , Persona de Mediana Edad , Invasividad Neoplásica , Adulto Joven
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