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1.
Brain ; 147(6): 2169-2184, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38662500

RESUMEN

Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in 5XFAD mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissues from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2) and the excitatory NMDA and AMPA type glutamate receptors. We performed patch-clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and decreased GABAA receptor subunit expression, as well as increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced amyloid-ß pathology and cognitive deficits, could also reverse elevations of the NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with US Food and Drug Administration-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.


Asunto(s)
Enfermedad de Alzheimer , Ratones Transgénicos , Convulsiones , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Convulsiones/metabolismo , Convulsiones/fisiopatología , Ratones , Masculino , Humanos , Femenino , Pentilenotetrazol/toxicidad , Anciano , Modelos Animales de Enfermedad , Excitación Neurológica/efectos de los fármacos , Anciano de 80 o más Años
2.
Eur J Neurosci ; 59(12): 3337-3352, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38654472

RESUMEN

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is caused by a loss-of-function mutation in CDKL5 gene, encoding a serine-threonine kinase highly expressed in the brain. CDD manifests with early-onset epilepsy, autism, motor impairment and severe intellectual disability. While there are no known treatments for CDD, the use of cannabidiol has recently been introduced into clinical practice for neurodevelopmental disorders. Given the increased clinical utilization of cannabidiol, we examined its efficacy in the CDKL5R59X knock-in (R59X) mice, a CDD model based on a human mutation that exhibits both lifelong seizure susceptibility and behavioural deficits. We found that cannabidiol pre-treatment rescued the increased seizure susceptibility in response to the chemoconvulsant pentylenetetrazol (PTZ), attenuated working memory and long-term memory impairments, and rescued social deficits in adult R59X mice. To elucidate a potential mechanism, we compared the developmental hippocampal and cortical expression of common endocannabinoid (eCB) targets in R59X mice and their wild-type littermates, including cannabinoid type 1 receptor (CB1R), transient receptor potential vanilloid type 1 (TRPV1) and 2 (TRPV2), G-coupled protein receptor 55 (GPR55) and adenosine receptor 1 (A1R). Many of these eCB targets were developmentally regulated in both R59X and wild-type mice. In addition, adult R59X mice demonstrated significantly decreased expression of CB1R and TRPV1 in the hippocampus, and TRPV2 in the cortex, while TRPV1 was increased in the cortex. These findings support the potential for dysregulation of eCB signalling as a plausible mechanism and therapeutic target in CDD, given the efficacy of cannabidiol to attenuate hyperexcitability and behavioural deficits in this disorder.


Asunto(s)
Cannabidiol , Proteínas Serina-Treonina Quinasas , Convulsiones , Animales , Cannabidiol/farmacología , Convulsiones/tratamiento farmacológico , Convulsiones/genética , Convulsiones/metabolismo , Ratones , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB1/metabolismo , Síndromes Epilépticos/genética , Síndromes Epilépticos/tratamiento farmacológico , Pentilenotetrazol , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos , Modelos Animales de Enfermedad , Técnicas de Sustitución del Gen/métodos , Masculino , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Endocannabinoides/metabolismo , Conducta Animal/efectos de los fármacos , Ratones Endogámicos C57BL , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Espasmos Infantiles , Receptores de Cannabinoides
3.
Brain ; 145(1): 324-339, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-34264340

RESUMEN

The risk of seizures is 10-fold higher in patients with Alzheimer's disease than the general population, yet the mechanisms underlying this susceptibility and the effects of these seizures are poorly understood. To elucidate the proposed bidirectional relationship between Alzheimer's disease and seizures, we studied human brain samples (n = 34) from patients with Alzheimer's disease and found that those with a history of seizures (n = 14) had increased amyloid-ß and tau pathology, with upregulation of the mechanistic target of rapamycin (mTOR) pathway, compared with patients without a known history of seizures (n = 20). To establish whether seizures accelerate the progression of Alzheimer's disease, we induced chronic hyperexcitability in the five times familial Alzheimer's disease mouse model by kindling with the chemoconvulsant pentylenetetrazol and observed that the mouse model exhibited more severe seizures than the wild-type. Furthermore, kindled seizures exacerbated later cognitive impairment, Alzheimer's disease neuropathology and mTOR complex 1 activation. Finally, we demonstrated that the administration of the mTOR inhibitor rapamycin following kindled seizures rescued enhanced remote and long-term memory deficits associated with earlier kindling and prevented seizure-induced increases in Alzheimer's disease neuropathology. These data demonstrated an important link between chronic hyperexcitability and progressive Alzheimer's disease pathology and suggest a mechanism whereby rapamycin may serve as an adjunct therapy to attenuate progression of the disease.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Pentilenotetrazol/toxicidad , Convulsiones/metabolismo
4.
Epilepsy Behav ; 143: 109194, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37119576

RESUMEN

Early-life seizures can be refractory to conventional antiseizure medications (ASMs) and can also result in chronic epilepsy and long-term behavioral and cognitive deficits. Treatments targeting age-specific mechanisms contributing to epilepsy would be of clinical benefit. One such target is the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subtype of excitatory glutamate receptor, which is upregulated in the developing brain. Perampanel is a non-competitive, selective AMPAR antagonist that is FDA-approved for focal onset seizures (FOS) or primary generalized tonic-clonic seizures (PGTC) in children and adults. However, the efficacy of perampanel treatment in epilepsy patients younger than 4 years has been less documented. We thus tested the efficacy of perampanel in two early-life seizure models: (1) a rat model of hypoxia-induced neonatal seizures and (2) a mouse model of Dravet syndrome with hyperthermia-induced seizures. Pretreatment with perampanel conferred dose-dependent protection against early-life seizures in both experimental models. These findings suggest that AMPAR-mediated hyperexcitability could be involved in the pathophysiology of early-life seizures, which may be amenable to treatment with perampanel.


Asunto(s)
Epilepsia , Roedores , Ratones , Ratas , Animales , Anticonvulsivantes/efectos adversos , Resultado del Tratamiento , Epilepsia/tratamiento farmacológico , Piridonas
5.
Planta ; 256(1): 9, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35696004

RESUMEN

MAIN CONCLUSION: The present review summarizes recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics, discusses its importance in plant genomes, and highlights its chemical nature and functions. Adenine methylation is an epigenetic modification present in DNA (6mA) and RNA (m6A) that has a regulatory function in many cellular processes. This modification occurs through a reversible reaction that covalently binds a methyl group, usually at the N6 position of the purine ring. This modification carries biophysical properties that affect the stability of nucleic acids as well as their binding affinity with other molecules. DNA 6mA has been related to genome stability, gene expression, DNA replication, and repair mechanisms. Recent advances have shown that 6mA in plant genomes is related to development and stress response. In this review, we present recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics. We discuss the key elements of this modification, focusing mainly on its importance in plant genomes. Furthermore, we highlight its chemical nature and the regulatory effects that it exerts on gene expression and plant development. Finally, we emphasize the functions of 6mA in photosynthesis, stress, and flowering.


Asunto(s)
Adenina , Metilación de ADN , ADN/genética , ADN/metabolismo , Metilación de ADN/genética , Epigénesis Genética , Genoma de Planta/genética
6.
Brain ; 143(1): 191-209, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31834353

RESUMEN

Temporal lobe epilepsy represents a major cause of drug-resistant epilepsy. Cognitive impairment is a frequent comorbidity, but the mechanisms are not fully elucidated. We hypothesized that the cognitive impairment in drug-resistant temporal lobe epilepsy could be due to perturbations of amyloid and tau signalling pathways related to activation of stress kinases, similar to those observed in Alzheimer's disease. We examined these pathways, as well as amyloid-ß and tau pathologies in the hippocampus and temporal lobe cortex of drug-resistant temporal lobe epilepsy patients who underwent temporal lobe resection (n = 19), in comparison with age- and region-matched samples from neurologically normal autopsy cases (n = 22). Post-mortem temporal cortex samples from Alzheimer's disease patients (n = 9) were used as positive controls to validate many of the neurodegeneration-related antibodies. Western blot and immunohistochemical analysis of tissue from temporal lobe epilepsy cases revealed increased phosphorylation of full-length amyloid precursor protein and its associated neurotoxic cleavage product amyloid-ß*56. Pathological phosphorylation of two distinct tau species was also increased in both regions, but increases in amyloid-ß1-42 peptide, the main component of amyloid plaques, were restricted to the hippocampus. Furthermore, several major stress kinases involved in the development of Alzheimer's disease pathology were significantly activated in temporal lobe epilepsy brain samples, including the c-Jun N-terminal kinase and the protein kinase R-like endoplasmic reticulum kinase. In temporal lobe epilepsy cases, hippocampal levels of phosphorylated amyloid precursor protein, its pro-amyloidogenic processing enzyme beta-site amyloid precursor protein cleaving enzyme 1, and both total and hyperphosphorylated tau expression, correlated with impaired preoperative executive function. Our study suggests that neurodegenerative and stress-related processes common to those observed in Alzheimer's disease may contribute to cognitive impairment in drug-resistant temporal lobe epilepsy. In particular, we identified several stress pathways that may represent potential novel therapeutic targets.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Disfunción Cognitiva/patología , Epilepsia del Lóbulo Temporal/patología , Hipocampo/patología , Fragmentos de Péptidos/metabolismo , Placa Amiloide/patología , Lóbulo Temporal/patología , Proteínas tau/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/metabolismo , Autopsia , Estudios de Casos y Controles , Niño , Preescolar , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/fisiopatología , Epilepsia Refractaria/complicaciones , Epilepsia Refractaria/metabolismo , Epilepsia Refractaria/patología , Epilepsia Refractaria/cirugía , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/metabolismo , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Hipocampo/metabolismo , Hipocampo/cirugía , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Placa Amiloide/metabolismo , Lóbulo Temporal/metabolismo , Lóbulo Temporal/cirugía , Adulto Joven , eIF-2 Quinasa/metabolismo
7.
Dev Psychobiol ; 63(8): e22204, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34813102

RESUMEN

The study of emotion regulation often addresses control of negative emotion. Researchers have proposed that affective balance is an indicator of emotion regulation that incorporates the role of positive emotion in the context of negative emotional experiences. Environmental and individual factors, such as family processes and biological stress regulation, are known to shape emotion regulation. The present study investigated whether child diurnal cortisol, an indicator of biological stress regulation, moderated the association between family routines and observed affective balance. Children (N = 222; M age = 4.70 years, SD = 0.60) from low-income households provided saliva samples to measure diurnal cortisol and completed a behavioral task designed to elicit negative emotions. Affective balance was defined as the difference score between the proportion of positive and negative emotional expressions displayed during the task. A higher affective balance score indicated greater positive compared with negative emotional displays. Simple slope analyses indicated that for children with a low morning cortisol intercept, more frequent family routines were associated with more affective balance. This pattern was not observed in children with average or high morning cortisol. Positive family routines may play an important role in shaping affective balance among children with disrupted cortisol levels from low-income backgrounds.


Asunto(s)
Hidrocortisona , Saliva , Niño , Preescolar , Ritmo Circadiano/fisiología , Emociones/fisiología , Familia , Humanos , Hidrocortisona/metabolismo , Pobreza , Saliva/química , Estrés Psicológico/metabolismo
8.
Int J Obes (Lond) ; 44(3): 646-655, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31477784

RESUMEN

BACKGROUND/OBJECTIVES: Associations between overweight and altered stress biology have been reported cross-sectionally during childhood, but it is unclear whether overweight precedes altered stress biology or if altered stress biology predicts greater likelihood of overweight over time. The current longitudinal study investigates associations between overweight/obesity, salivary alpha amylase and cortisol morning intercept, diurnal slope, and reactivity to social stress in a cohort of low-income children during preschool and middle childhood. SUBJECTS/METHODS: Children were recruited through Head Start and were observed and followed into middle childhood (N = 257; M = 8.0 years). Height and weight were measured at both time points. Saliva samples were collected across the day and in response to a social challenge at both ages for alpha amylase and cortisol determination. RESULTS: Cross-lagged panel analyses indicated that overweight/obesity at preschool predicted lower morning alpha amylase (ß = -0.18, 95% CI: -0.34, -0.03; p = 0.023), lower morning cortisol (ß = -0.22, 95% CI: -0.38, -0.06; p = 0.006), lower sAA diurnal slope (ß = -0.18, 95% CI: -0.34, -0.03; p = 0.021), and lower cortisol stress reactivity (ß = -0.19, 95% CI: -0.35, -0.02; p = 0.031) in middle childhood. Lower alpha amylase reactivity at preschool was the only biological factor that predicted higher likelihood of overweight/obesity at middle childhood (ß = -0.20, 95% CI: -0.38, -0.01; p = 0.035). CONCLUSIONS: These findings suggest that overweight/obesity may be driving changes in stress biology across early-to-middle childhood, particularly in downregulation of morning levels of stress hormones, diurnal sAA slope, and cortisol reactivity to stress, rather than stress biology driving overweight/obesity.


Asunto(s)
Obesidad Infantil/epidemiología , Pobreza , Estrés Psicológico/epidemiología , Niño , Preescolar , Femenino , Humanos , Hidrocortisona/análisis , Estudios Longitudinales , Masculino , Sobrepeso/epidemiología , Saliva/química , alfa-Amilasas Salivales/análisis
9.
Adv Anat Pathol ; 27(5): 303-310, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32520749

RESUMEN

The diagnosis of primary adenocarcinoma of the urinary bladder may be challenging in routine practice. These tumors may morphologically and immunohistochemically overlap with urachal adenocarcinoma and colorectal adenocarcinoma. Further, their genetic background is poorly understood. We systematically searched the PubMed database for results of complex genetic evaluation of primary bladder adenocarcinoma subtypes. Subsequently, we designed our own series of bladder lesions. We evaluated 36 cases: 16 primary enteric-type adenocarcinomas, 7 urachal enteric adenocarcinomas, 3 primary mucinous/colloid adenocarcinomas, and 10 intestinal-type metaplasia/villous adenoma. Detailed clinical data were collected, and all cases were examined using targeted next-generation sequencing. On the basis of the literature, the first mutated gene in these tumors was reported to be KRAS in 11.3% of cases, followed by TERT promoter mutations in 28.5%. In addition to KRAS and TERT, other genes were also found to be frequently mutated in primary bladder adenocarcinoma, including TP53, PIK3CA, CTNNB1, APC, FBXW7, IDH2, and RB1. In our series, the most frequent gene mutations in primary enteric-type adenocarcinomas were as follows: TP53 (56%); BRCA2, KMT2B (both 33%); NOTCH2, KDR, ARID1B, POLE, PTEN, KRAS (all 28%); in urachal enteric adenocarcinoma they were as follows: TP53 (86%); PTEN, NOTCH (both 43%); in primary mucinous/colloid adenocarcinomas they were as follows: KRAS, GRIN2A, AURKB (all 67%); and, in intestinal-type metaplasia/villous adenoma, they were as follows: APC, PRKDC (both 60%); ROS1, ATM, KMT2D (all 50%). No specific mutational pattern was identified using cluster analysis for any of the groups. Herein, we describe the pathologic features and immunohistochemical staining patterns traditionally used in the differential diagnoses of glandular lesions of the bladder in routine surgical pathology. We outline the mutational landscape of these lesions as an aggregate of published data with additional data from our cohort. Although diagnostically not discriminatory, we document that the most common genetic alterations shared between these glandular neoplasms include TP53, APC (in the Wnt pathway), and KRAS (in the MAPK pathway) mutations.


Asunto(s)
Adenocarcinoma Mucinoso/genética , Adenocarcinoma/genética , Adenoma/genética , Neoplasias Intestinales/genética , Neoplasias de la Vejiga Urinaria/genética , Adenocarcinoma/patología , Adenocarcinoma Mucinoso/patología , Adenoma/patología , Biomarcadores de Tumor/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Intestinales/patología , Metaplasia/genética , Metaplasia/metabolismo , Neoplasias de la Vejiga Urinaria/patología
10.
Lancet ; 392(10162): 2353-2366, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30355464

RESUMEN

BACKGROUND: Based on previous findings, we hypothesised that radiotherapy to the prostate would improve overall survival in men with metastatic prostate cancer, and that the benefit would be greatest in patients with a low metastatic burden. We aimed to compare standard of care for metastatic prostate cancer, with and without radiotherapy. METHODS: We did a randomised controlled phase 3 trial at 117 hospitals in Switzerland and the UK. Eligible patients had newly diagnosed metastatic prostate cancer. We randomly allocated patients open-label in a 1:1 ratio to standard of care (control group) or standard of care and radiotherapy (radiotherapy group). Randomisation was stratified by hospital, age at randomisation, nodal involvement, WHO performance status, planned androgen deprivation therapy, planned docetaxel use (from December, 2015), and regular aspirin or non-steroidal anti-inflammatory drug use. Standard of care was lifelong androgen deprivation therapy, with up-front docetaxel permitted from December, 2015. Men allocated radiotherapy received either a daily (55 Gy in 20 fractions over 4 weeks) or weekly (36 Gy in six fractions over 6 weeks) schedule that was nominated before randomisation. The primary outcome was overall survival, measured as the number of deaths; this analysis had 90% power with a one-sided α of 2·5% for a hazard ratio (HR) of 0·75. Secondary outcomes were failure-free survival, progression-free survival, metastatic progression-free survival, prostate cancer-specific survival, and symptomatic local event-free survival. Analyses used Cox proportional hazards and flexible parametric models, adjusted for stratification factors. The primary outcome analysis was by intention to treat. Two prespecified subgroup analyses tested the effects of prostate radiotherapy by baseline metastatic burden and radiotherapy schedule. This trial is registered with ClinicalTrials.gov, number NCT00268476. FINDINGS: Between Jan 22, 2013, and Sept 2, 2016, 2061 men underwent randomisation, 1029 were allocated the control and 1032 radiotherapy. Allocated groups were balanced, with a median age of 68 years (IQR 63-73) and median amount of prostate-specific antigen of 97 ng/mL (33-315). 367 (18%) patients received early docetaxel. 1082 (52%) participants nominated the daily radiotherapy schedule before randomisation and 979 (48%) the weekly schedule. 819 (40%) men had a low metastatic burden, 1120 (54%) had a high metastatic burden, and the metastatic burden was unknown for 122 (6%). Radiotherapy improved failure-free survival (HR 0·76, 95% CI 0·68-0·84; p<0·0001) but not overall survival (0·92, 0·80-1·06; p=0·266). Radiotherapy was well tolerated, with 48 (5%) adverse events (Radiation Therapy Oncology Group grade 3-4) reported during radiotherapy and 37 (4%) after radiotherapy. The proportion reporting at least one severe adverse event (Common Terminology Criteria for Adverse Events grade 3 or worse) was similar by treatment group in the safety population (398 [38%] with control and 380 [39%] with radiotherapy). INTERPRETATION: Radiotherapy to the prostate did not improve overall survival for unselected patients with newly diagnosed metastatic prostate cancer. FUNDING: Cancer Research UK, UK Medical Research Council, Swiss Group for Clinical Cancer Research, Astellas, Clovis Oncology, Janssen, Novartis, Pfizer, and Sanofi-Aventis.


Asunto(s)
Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Anciano , Antineoplásicos/uso terapéutico , Supervivencia sin Enfermedad , Docetaxel/uso terapéutico , Hormona Liberadora de Gonadotropina/agonistas , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Orquiectomía , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/cirugía , Radioterapia/efectos adversos , Nivel de Atención , Análisis de Supervivencia , Resultado del Tratamiento
11.
BMC Med Genet ; 20(1): 77, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31064326

RESUMEN

BACKGROUND: Mitochondrial respiratory chain consists of five complexes encoded by nuclear and mitochondrial genomes. Mitochondrial aminoacyl-tRNA synthetases are key enzymes in the synthesis of such complexes. Bi-allelic variants of VARS2, a nuclear gene encoding for valyl-tRNA (Val-tRNA) synthetase, are associated to several forms of mitochondrial encephalopathies or cardiomyoencephalopathies. Among these, the rare homozygous c.1100C > T (p.Thr367Ile) mutation variably presents with progressive developmental delay, axial hypotonia, limbs spasticity, drug-resistant epilepsy leading, in some cases, to premature death. Yet only six cases, of which three are siblings, harbouring this homozygous mutation have been described worldwide. CASE PRESENTATION: Hereby, we report two additional cases of two non-related young girls from Sardinia, born from non-consanguineous and healthy parents, carrying the aforesaid homozygous VARS2 variant. At onset both the patients presented with worsening psychomotor delay, muscle hypotonia and brisk tendon reflexes. Standard genetic tests were normal, as well as metabolic investigations. Brain MRI showed unspecific progressive abnormalities, such as corpus callosum hypoplasia (patient A) and cerebellar atrophy (patient A and B). Diagnosis was reached by adopting massive parallel next generation sequencing. Notably clinical phenotype of the first patient appears to be milder compared to previous known cases. The second patient eventually developed refractory epilepsy and currently presents with severe global impairment. Because no specific treatment is available as yet, both patients are treated with supporting antioxidant compounds along with symptomatic therapies. CONCLUSIONS: Given the paucity of clinical data about this very rare mitochondrial encephalopathy, our report might contribute to broaden the phenotypic spectrum of the disorder. Moreover, noteworthy, three out of five pedigrees so far described belong to the Northern Sardinia ethnicity.


Asunto(s)
Antígenos HLA/genética , Encefalomiopatías Mitocondriales/genética , Valina-ARNt Ligasa/genética , Niño , Preescolar , Electroencefalografía , Femenino , Homocigoto , Humanos , Imagen por Resonancia Magnética , Encefalomiopatías Mitocondriales/diagnóstico por imagen , Encefalomiopatías Mitocondriales/fisiopatología , Mutación , Fenotipo
12.
Ann Neurol ; 83(2): 311-327, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29331082

RESUMEN

OBJECTIVE: Temporal lobe epilepsy (TLE) is a chronic epilepsy syndrome defined by seizures and progressive neurological disabilities, including cognitive impairments, anxiety, and depression. Here, human TLE specimens were investigated focusing on the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) and complex 2 (mTORC2) activities in the brain, given that both pathways may represent unique targets for treatment. METHODS: Surgically resected hippocampal and temporal lobe samples from therapy-resistant TLE patients were analyzed by western blotting to quantify the expression of established mTORC1 and mTORC2 activity markers and upstream or downstream signaling pathways involving the two complexes. Histological and immunohistochemical techniques were used to assess hippocampal and neocortical structural abnormalities and cell-specific expression of individual biomarkers. Samples from patients with focal cortical dysplasia (FCD) type II served as positive controls. RESULTS: We found significantly increased expression of phospho-mTOR (Ser2448), phospho-S6 (Ser235/236), phospho-S6 (Ser240/244), and phospho-Akt (Ser473) in TLE samples compared to controls, consistent with activation of both mTORC1 and mTORC2. Our work identified the phosphoinositide 3-kinase and Ras/extracellular signal-regulated kinase signaling pathways as potential mTORC1 and mTORC2 upstream activators. In addition, we found that overactive mTORC2 signaling was accompanied by induction of two protein kinase B-dependent prosurvival pathways, as evidenced by increased inhibitory phosphorylation of forkhead box class O3a (Ser253) and glycogen synthase kinase 3 beta (Ser9). INTERPRETATION: Our data demonstrate that mTOR signaling is significantly dysregulated in human TLE, offering new targets for pharmacological interventions. Specifically, clinically available drugs that suppress mTORC1 without compromising mTOR2 signaling, such as rapamycin and its analogs, may represent a new group of antiepileptogenic agents in TLE patients. Ann Neurol 2018;83:311-327.


Asunto(s)
Epilepsia del Lóbulo Temporal/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Transducción de Señal/fisiología , Adulto , Encéfalo/metabolismo , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Serina-Treonina Quinasas TOR/metabolismo , Adulto Joven
13.
Histopathology ; 75(2): 174-184, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30895640

RESUMEN

AIM: To describe a group of distinct low-grade oncocytic renal tumours that demonstrate CD117 negative/cytokeratin (CK) 7-positive immunoprofile. METHODS AND RESULTS: We identified 28 such tumours from four large renal tumour archives. We performed immunohistochemistry for: CK7, CD117, PAX8, CD10, AMACR, e-cadherin, CK20, CA9, AE1/AE3, vimentin, BerEP4, MOC31, CK5/6, p63, HMB45, melan A, CD15 and FH. In 14 cases we performed array CGH, with a successful result in nine cases. Median patient age was 66 years (range 49-78 years) with a male-to-female ratio of 1:1.8. Median tumour size was 3 cm (range 1.1-13.5 cm). All were single tumours, solid and tan-brown, without a syndromic association. On microscopy, all cases showed solid and compact nested growth. There were frequent areas of oedematous stroma with loosely arranged cells. The tumour cells had oncocytic cytoplasm with uniformly round to oval nuclei, but without significant irregularities, and showed only focal perinuclear halos. Negative CD117 and positive CK7 reactivity were present in all cases (in two cases there was focal and very weak CD117 reactivity). Uniform reactivity was found for PAX8, AE1/AE3, e-cadherin, BerEP4 and MOC31. Negative stains included CA9, CK20, vimentin, CK5/6, p63, HMB45, Melan A and CD15. CD10 and AMACR were either negative or focally positive; FH was retained. On array CGH, there were frequent deletions at 19p13.3 (seven of nine), 1p36.33 (five of nine) and 19q13.11 (four of nine); disomic status was found in two of nine cases. On follow-up (mean 31.8 months, range 1-118), all patients were alive with no disease progression. CONCLUSION: Low-grade oncocytic tumours that are CD117-negative/CK7-positive demonstrate consistent and readily recognisable morphology, immunoprofile and indolent behaviour.


Asunto(s)
Adenoma Oxifílico/patología , Neoplasias Renales/patología , Anciano , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Queratina-7/análisis , Queratina-7/biosíntesis , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-kit/análisis , Proteínas Proto-Oncogénicas c-kit/biosíntesis
14.
Radiographics ; 39(2): 307-318, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30681901

RESUMEN

Full-field digital mammography (FFDM), the standard of care for breast cancer screening, has some limitations. With the advent of digital breast tomosynthesis (DBT), improvements including decreased recall rates and increased cancer detection rates have been observed. The quasi-three-dimensional capability of DBT reduces breast tissue overlap, a significant limitation of FFDM. However, early studies demonstrate that a few cancers detected at FFDM may not be diagnosed at DBT-only screening, and lesions with calcifications as the dominant feature may look less suspicious at DBT or not be visible at all. These findings support the use of combined FFDM and DBT protocols to optimize screening performance. However, this combination would approximately double the patient's radiation exposure. The development of computer algorithms that generate two-dimensional synthesized mammography (SM) views from DBT has improved calcification conspicuity and sensitivity. Therefore, SM may substitute for FFDM in screening protocols, reducing radiation exposure. DBT plus SM demonstrates significantly better performance than that of FFDM alone, although there are reports of missed malignant calcifications. Thus, some centers continue to perform FFDM with DBT. Use of DBT in breast imaging has also necessitated the development of DBT-guided biopsy. DBT-guided biopsy may have a higher success rate than that of stereotactic biopsy, with a shorter procedure time. While DBT brings substantial improvements to breast cancer imaging, it is important to be aware of its strengths and limitations regarding detection of calcifications. This article reviews the imaging appearance of breast calcifications at DBT, discusses calcification biopsy techniques, and provides an overview of the current literature. Online supplemental material is available for this article. ©RSNA, 2019 An earlier incorrect version of this article appeared online. This article was corrected on February 13, 2019.


Asunto(s)
Biopsia/métodos , Enfermedades de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Mamografía , Mama/patología , Enfermedades de la Mama/patología , Neoplasias de la Mama/patología , Diagnóstico Diferencial , Detección Precoz del Cáncer , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Mamografía/métodos , Sensibilidad y Especificidad
15.
Mycoses ; 62(3): 252-260, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30565742

RESUMEN

Invasive fungal infections (IFI) of the Central Nervous System (IFI-CNS) and Paranasal Sinuses (IFI-PS) are rare, life-threatening infections in haematologic patients, and their management remains a challenge despite the availability of new diagnostic techniques and novel antifungal agents. In addition, analyses of large cohorts of patients focusing on these rare IFI are still lacking. Between January 2010 and December 2016, 89 consecutive cases of Proven (53) or Probable (36) IFI-CNS (71/89) and IFI-PS (18/89) were collected in 34 haematological centres. The median age was 40 years (range 5-79); acute leukaemia was the most common underlying disease (69%) and 29% of cases received a previous allogeneic stem cell transplant. Aspergillus spp. were the most common pathogens (69%), followed by mucormycetes (22%), Cryptococcus spp. (4%) and Fusarium spp. (2%). The lung was the primary focus of fungal infection (48% of cases). The nervous system biopsy was performed in 10% of IFI-CNS, and a sinus biopsy was performed in 56% of IFI-PS (P = 0.03). The Galactomannan test on cerebrospinal fluid has been performed in 42% of IFI-CNS (30/71), and it was positive in 67%. Eighty-four pts received a first-line antifungal therapy with Amphotericine B in 58% of cases, Voriconazole in 31% and both in 11%. Moreover, 58% of patients received 2 or more lines of therapy and 38% were treated with a combination of 2 or more antifungal drugs. The median duration of antifungal therapy was 60 days (range 5-835). A surgical intervention was performed in 26% of cases but only 10% of IFI-CNS underwent neurosurgical intervention. The overall response rate to antifungal therapy (complete or partial response) was 57%, and 1-year overall survival was 32% without significant differences between IFI-CNS and IFI-PS. The overall mortality was 69% but the IFI attributable mortality was 33%. Mortality of IFI-CNS/PS remains high but, compared to previous historical data, it seems to be reduced probably due to the availability of newer antifungal drugs. The results arising from this large contemporary cohort of cases may allow a more effective diagnostic and therapeutic management of these very rare IFI complications in haematologic patients.


Asunto(s)
Antifúngicos/uso terapéutico , Infecciones Fúngicas del Sistema Nervioso Central/epidemiología , Desbridamiento , Hongos/clasificación , Hongos/aislamiento & purificación , Neoplasias Hematológicas/complicaciones , Sinusitis/epidemiología , Adolescente , Adulto , Anciano , Infecciones Fúngicas del Sistema Nervioso Central/microbiología , Infecciones Fúngicas del Sistema Nervioso Central/terapia , Líquido Cefalorraquídeo/microbiología , Niño , Preescolar , Estudios Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Senos Paranasales/microbiología , Sinusitis/microbiología , Sinusitis/terapia , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
16.
Breast Cancer Res Treat ; 172(2): 487-496, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30140962

RESUMEN

PURPOSE: Breast fibroglandular tissue (FGT), as visualized on a mammogram (mammographic density, MD), is one of the strongest known risk factors for breast cancer. FGT is also visible on breast MRI, and increased background parenchymal enhancement (BPE) in the FGT has been identified as potentially a major breast cancer risk factor. The aim of this exploratory study was to examine the biologic basis of BPE. METHODS: We examined the unaffected contra-lateral breast of 80 breast cancer patients undergoing a prophylactic mastectomy before any treatment other than surgery of their breast cancer. BPE was classified on the BI-RADS scale (minimal/mild/moderate/marked). Slides were stained for microvessel density (MVD), CD34 (another measure of endothelial density), glandular tissue within the FGT and VEGF. Spearman correlations were used to evaluate the associations between BPE and these pathologic variables. RESULTS: In pre-menopausal patients, BPE was highly correlated with MVD, CD34 and glandular concentration within the FGT, and the pathologic variables were themselves highly correlated. The expression of VEGF was effectively confined to terminal duct lobular unit (TDLU) epithelium. The same relationships of the four pathologic variables with BPE were seen in post-menopausal patients, but the relationships were much weaker and not statistically significant. CONCLUSION: The strong correlation of BPE and MVD together with the high correlation of MVD with glandular concentration seen in pre-menopausal patients indicates that increased breast cancer risk associated with BPE in pre-menopausal women is likely to result from its association with increased concentration of glandular tissue in the FGT. The effective confinement of VEGF expression to the TDLUs shows that the signal for MVD growth arises directly from the glandular tissue. Further studies are needed to understand the basis of BPE in post-menopausal women.


Asunto(s)
Neoplasias de la Mama/patología , Mama/patología , Imagen por Resonancia Magnética , Tejido Parenquimatoso/patología , Adulto , Mama/diagnóstico por imagen , Densidad de la Mama/fisiología , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Mamografía , Persona de Mediana Edad , Tejido Parenquimatoso/diagnóstico por imagen , Factores de Riesgo
17.
BMC Genet ; 19(1): 32, 2018 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-29776332

RESUMEN

BACKGROUND: The ends of linear chromosomes, the telomeres, comprise repetitive DNA sequences in complex with proteins that protects them from being processed by the DNA repair machinery. Cancer cells need to counteract the shortening of telomere repeats during replication for their unlimited proliferation by reactivating the reverse transcriptase telomerase or by using the alternative lengthening of telomeres (ALT) pathway. The different telomere maintenance (TM) mechanisms appear to involve hundreds of proteins but their telomere repeat length related activities are only partly understood. Currently, a database that integrates information on TM relevant genes is missing. DESCRIPTION: To provide a resource for studies that dissect TM features, we here introduce the TelNet database at http://www.cancertelsys.org/telnet/ . It offers a comprehensive compilation of more than 2000 human and 1100 yeast genes linked to telomere maintenance. These genes were annotated in terms of TM mechanism, associated specific functions and orthologous genes, a TM significance score and information from peer-reviewed literature. This TM information can be retrieved via different search and view modes and evaluated for a set of genes as demonstrated for an exemplary application. CONCLUSION: TelNet supports the annotation of genes identified from bioinformatics analysis pipelines to reveal possible connections with TM networks. We anticipate that TelNet will be a helpful resource for researchers that study telomeres.


Asunto(s)
Bases de Datos Genéticas , Proteínas de Saccharomyces cerevisiae/genética , Telomerasa/genética , Homeostasis del Telómero/genética , Proteínas de Unión a Telómeros/genética , Humanos
18.
Ann Hematol ; 97(9): 1717-1726, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29705860

RESUMEN

Infections by multidrug-resistant (MDR) bacteria are a worrisome phenomenon in hematological patients. Data on the incidence of MDR colonization and related bloodstream infections (BSIs) in haematological patients are scarce. A multicentric prospective observational study was planned in 18 haematological institutions during a 6-month period. All patients showing MDR rectal colonization as well as occurrence of BSI at admission were recorded. One-hundred forty-four patients with MDR colonization were observed (6.5% of 2226 admissions). Extended spectrum beta-lactamase (ESBL)-producing (ESBL-P) enterobacteria were observed in 64/144 patients, carbapenem-resistant (CR) Gram-negative bacteria in 85/144 and vancomycin-resistant enterococci (VREs) in 9/144. Overall, 37 MDR-colonized patients (25.7%) developed at least one BSI; 23 of them (62.2%, 16% of the whole series) developed BSI by the same pathogen (MDRrel BSI), with a rate of 15.6% (10/64) for ESBL-P enterobacteria, 14.1% (12/85) for CR Gram-negative bacteria and 11.1% (1/9) for VRE. In 20/23 cases, MDRrel BSI occurred during neutropenia. After a median follow-up of 80 days, 18 patients died (12.5%). The 3-month overall survival was significantly lower for patients colonized with CR Gram-negative bacteria (83.6%) and VRE (77.8%) in comparison with those colonized with ESBL-P enterobacteria (96.8%). CR-rel BSI and the presence of a urinary catheter were independent predictors of mortality. MDR rectal colonization occurs in 6.5% of haematological inpatients and predicts a 16% probability of MDRrel BSI, particularly during neutropenia, as well as a higher probability of unfavourable outcomes in CR-rel BSIs. Tailored empiric antibiotic treatment should be decided on the basis of colonization.


Asunto(s)
Bacteriemia/epidemiología , Infecciones Bacterianas/epidemiología , Farmacorresistencia Bacteriana Múltiple , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/microbiología , Infecciones Bacterianas/sangre , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/microbiología , Infecciones Relacionadas con Catéteres/epidemiología , Niño , Preescolar , Femenino , Neoplasias Hematológicas/microbiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Arch Womens Ment Health ; 21(3): 375-382, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29168023

RESUMEN

Recent work suggests that key aspects of sensitive parenting (e.g., warmth, emotional attunement) may be shaped in part by biology, specifically the neuropeptide oxytocin. However, some studies have found that oxytocin may not act in expected ways in higher-risk populations (e.g., those with postnatal depression or borderline personality disorder). This study examined the relation between oxytocin and parenting among mothers with varying levels of early life stress. Forty low-income mothers and their 34- to 48-month-old child participated in this study. Mother-child dyads were observed in an interaction task in their home, and videos of these interactions were later coded for parenting behaviors. Mothers' oxytocin production before and after the interaction task was assessed through saliva. Mothers' early stress was assessed via the Adverse Childhood Experiences Scale (ACES; Felitti et al. Am J Prev Med 14:245-258, 1998). For mothers with low ACEs, higher oxytocin secretion was associated with more positive parenting. For mothers with high ACEs, higher oxytocin secretion was associated with lower levels of positive parenting. Oxytocin may be operating differently for mothers who experienced harsh early social environments, supporting more defensive behaviors and harsh parenting than anxiolytic and prosocial behaviors.


Asunto(s)
Relaciones Madre-Hijo/psicología , Madres/psicología , Oxitocina/metabolismo , Responsabilidad Parental/psicología , Pobreza , Saliva/química , Estrés Psicológico , Adulto , Niño , Femenino , Humanos , Acontecimientos que Cambian la Vida , Conducta Materna/psicología , Apego a Objetos , Oxitocina/análisis , Pobreza/psicología , Estrés Psicológico/psicología
20.
Dev Psychobiol ; 60(4): 364-379, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29388194

RESUMEN

Childhood poverty is hypothesized to increase risk for mental and physical health problems at least in part through dysregulation of the hypothalamic-pituitary-adrenal axis. However, less is known about the specific psychosocial stressors associated with cortisol reactivity and regulation for children living in poverty. The current study investigates negative life events, household chaos, and family conflict in preschool and middle childhood as potential predictors of cortisol regulation in low-income 7-10 year olds (N = 242; M age = 7.9 years). Participants were assessed in preschool and participated in a follow-up assessment in middle childhood, during which diurnal free cortisol and free cortisol reactivity to the Trier Social Stress Test for Children (TSST-C) were assessed. Household chaos during preschool predicted a more blunted diurnal cortisol slope in middle childhood. Greater negative life events during preschool and greater concurrent family conflict were associated with increased free cortisol reactivity in middle childhood.


Asunto(s)
Conflicto Familiar , Hidrocortisona/metabolismo , Acontecimientos que Cambian la Vida , Pobreza , Estrés Psicológico/metabolismo , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Saliva
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