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1.
Hippocampus ; 34(5): 241-260, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38415962

RESUMO

The medial temporal lobe (MTL) cortex, located adjacent to the hippocampus, is crucial for memory and prone to the accumulation of certain neuropathologies such as Alzheimer's disease neurofibrillary tau tangles. The MTL cortex is composed of several subregions which differ in their functional and cytoarchitectonic features. As neuroanatomical schools rely on different cytoarchitectonic definitions of these subregions, it is unclear to what extent their delineations of MTL cortex subregions overlap. Here, we provide an overview of cytoarchitectonic definitions of the entorhinal and parahippocampal cortices as well as Brodmann areas (BA) 35 and 36, as provided by four neuroanatomists from different laboratories, aiming to identify the rationale for overlapping and diverging delineations. Nissl-stained series were acquired from the temporal lobes of three human specimens (two right and one left hemisphere). Slices (50 µm thick) were prepared perpendicular to the long axis of the hippocampus spanning the entire longitudinal extent of the MTL cortex. Four neuroanatomists annotated MTL cortex subregions on digitized slices spaced 5 mm apart (pixel size 0.4 µm at 20× magnification). Parcellations, terminology, and border placement were compared among neuroanatomists. Cytoarchitectonic features of each subregion are described in detail. Qualitative analysis of the annotations showed higher agreement in the definitions of the entorhinal cortex and BA35, while the definitions of BA36 and the parahippocampal cortex exhibited less overlap among neuroanatomists. The degree of overlap of cytoarchitectonic definitions was partially reflected in the neuroanatomists' agreement on the respective delineations. Lower agreement in annotations was observed in transitional zones between structures where seminal cytoarchitectonic features are expressed less saliently. The results highlight that definitions and parcellations of the MTL cortex differ among neuroanatomical schools and thereby increase understanding of why these differences may arise. This work sets a crucial foundation to further advance anatomically-informed neuroimaging research on the human MTL cortex.


Assuntos
Lobo Temporal , Humanos , Lobo Temporal/patologia , Neuroanatomia/métodos , Masculino , Giro Para-Hipocampal/patologia , Giro Para-Hipocampal/diagnóstico por imagem , Feminino , Idoso , Córtex Entorrinal/patologia , Córtex Entorrinal/anatomia & histologia , Laboratórios , Idoso de 80 Anos ou mais
2.
bioRxiv ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37292729

RESUMO

The medial temporal lobe (MTL) cortex, located adjacent to the hippocampus, is crucial for memory and prone to the accumulation of certain neuropathologies such as Alzheimer's disease neurofibrillary tau tangles. The MTL cortex is composed of several subregions which differ in their functional and cytoarchitectonic features. As neuroanatomical schools rely on different cytoarchitectonic definitions of these subregions, it is unclear to what extent their delineations of MTL cortex subregions overlap. Here, we provide an overview of cytoarchitectonic definitions of the cortices that make up the parahippocampal gyrus (entorhinal and parahippocampal cortices) and the adjacent Brodmann areas (BA) 35 and 36, as provided by four neuroanatomists from different laboratories, aiming to identify the rationale for overlapping and diverging delineations. Nissl-stained series were acquired from the temporal lobes of three human specimens (two right and one left hemisphere). Slices (50 µm thick) were prepared perpendicular to the long axis of the hippocampus spanning the entire longitudinal extent of the MTL cortex. Four neuroanatomists annotated MTL cortex subregions on digitized (20X resolution) slices with 5 mm spacing. Parcellations, terminology, and border placement were compared among neuroanatomists. Cytoarchitectonic features of each subregion are described in detail. Qualitative analysis of the annotations showed higher agreement in the definitions of the entorhinal cortex and BA35, while definitions of BA36 and the parahippocampal cortex exhibited less overlap among neuroanatomists. The degree of overlap of cytoarchitectonic definitions was partially reflected in the neuroanatomists' agreement on the respective delineations. Lower agreement in annotations was observed in transitional zones between structures where seminal cytoarchitectonic features are expressed more gradually. The results highlight that definitions and parcellations of the MTL cortex differ among neuroanatomical schools and thereby increase understanding of why these differences may arise. This work sets a crucial foundation to further advance anatomically-informed human neuroimaging research on the MTL cortex.

3.
Front Pain Res (Lausanne) ; 4: 1223932, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745801

RESUMO

Background: Disorders of the Gut-Brain Interaction (DGBIs) account for 50% of pediatric gastrointestinal (GI) consultations. Children with DGBIs have worse quality of life (QoL) than those with organic GI disorders such as inflammatory bowel disease and gastroesophageal reflux disease. Pediatric DGBIs patients, especially those with chronic abdominal pain (AP), have impaired QoL and increased psychological distress in the form of anxiety and depression. Percutaneous Electrical Nerve Field Stimulation (PENFS) therapy has been shown to be effective in improving symptoms and functioning in children with DGBIs. The treatment's impact on these patients' QoL is unknown. Methods: This prospective study evaluated changes in QoL, gastrointestinal symptoms, functional disability, somatization, global health, anxiety, and depression in patients aged 11-18 years who received PENFS therapy (IB-stim, NeurAxis, Versailles, IN) for treatment of pain related DGBIs, once a week for four consecutive weeks. Results: This study included 31 patients with an average age of 15.7 years (SD = 2); 80.6% were female. After PENFS therapy, patients reported significant reductions in abdominal pain, nausea severity, functional disability, somatization, and anxiety from baseline to week 4 (p < 0.05). Parents reported significant improvement in their child's QoL regarding physical function, psychosocial function, and generic core scale scores (p < 0.05). Parents also noted reduced abdominal pain, functional disability, and somatization. Average scores on the Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health scale significantly improved based on both patient and parent reports (p < 0.05). Our patients' QoL was significantly lower than healthy controls at baseline and after treatment (p < 0.05). Conclusion: Our research demonstrates that PENFS significantly enhances the QoL of children suffering from pain-related DGBIs, in addition to improvement in GI symptoms, daily functioning, somatization, global health, and psychological comorbidities. These findings demonstrate the effectiveness of PENFS and its potential to alleviate the suffering of countless children.

4.
J Psychosom Res ; 168: 111212, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36963165

RESUMO

OBJECTIVE: To investigate the relationship between history of anti-inflammatory medication use and delirium risk, as well as long-term mortality. METHODS: In this retrospective cohort study, subjects recruited between January 2016 and March 2020 were analyzed. Information about anti-inflammatory medication use history including aspirin, NSAIDs, glucosamine, and other anti-inflammatory drugs, was collected. Logistic regression analysis investigated the relationship between anti-inflammatory medications and delirium. Log-rank analysis and cox proportional hazards model investigated the relationship between anti-inflammatory medications and one-year mortality. RESULTS: The data from 1274 subjects were analyzed. The prevalence of delirium was significantly lower in subjects with NSAIDs usage (23.0%) than in those without NSAIDs usage (35.0%) (p < 0.001). Logistic regression analysis controlling for age, sex, dementia status, and hospitalization department showed that the risk of delirium tended to be reduced by a history of NSAIDs use (OR, 0.76 [95% CI, 0.55 to 1.03]). The one-year mortality in the subjects with NSAIDs (survival rate, 0.879 [95% CI, 0.845 to 0.906]) was significantly lower than in the subjects without NSAIDs (survival rate, 0.776 [95% CI, 0.746 to 0.803]) (p < 0.001). A history of NSAIDs use associated with the decreased risk of one-year mortality even after adjustment for age, sex, Charlson Comorbidity Index, delirium status, and hospitalization department (HR, 0.70 [95% CI, 0.51 to 0.96]). CONCLUSION: This study suggested that NSAIDs usage was associated with decreased delirium prevalence and lower one-year mortality. The potential benefit of NSAIDs on delirium risk and mortality were shown.


Assuntos
Anti-Inflamatórios não Esteroides , Delírio , Humanos , Estudos Retrospectivos , Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/uso terapêutico , Modelos de Riscos Proporcionais , Delírio/epidemiologia , Delírio/complicações
5.
Aging (Albany NY) ; 15(3): 601-616, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36734879

RESUMO

BACKGROUND: Metformin, a commonly prescribed anti-diabetic medication, has repeatedly been shown to hinder aging in pre-clinical models and to be associated with lower mortality for humans. It is, however, not well understood how metformin can potentially prolong lifespan from a biological standpoint. We hypothesized that metformin's potential mechanism of action for longevity is through its epigenetic modifications. METHODS: To test our hypothesis, we conducted a post-hoc analysis of available genome-wide DNA methylation (DNAm) data obtained from whole blood collected from inpatients with and without a history of metformin use. We assessed the methylation profile of 171 patients (first run) and only among 63 diabetic patients (second run) and compared the DNAm rates between metformin users and nonusers. RESULTS: Enrichment analysis from the Kyoto Encyclopedia of Genes and Genome (KEGG) showed pathways relevant to metformin's mechanism of action, such as longevity, AMPK, and inflammatory pathways. We also identified several pathways related to delirium whose risk factor is aging. Moreover, top hits from the Gene Ontology (GO) included HIF-1α pathways. However, no individual CpG site showed genome-wide statistical significance (p < 5E-08). CONCLUSION: This study may elucidate metformin's potential role in longevity through epigenetic modifications and other possible mechanisms of action.


Assuntos
Longevidade , Metformina , Humanos , Longevidade/genética , Metformina/farmacologia , Metformina/uso terapêutico , Metilação de DNA , Envelhecimento/genética , Epigênese Genética , DNA
6.
Aging (Albany NY) ; 14(22): 8927-8943, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36399107

RESUMO

PURPOSE: Metformin has been reported to improve age-related disorders, including dementia, and to lower mortality. This study was conducted to investigate whether metformin use lower delirium risk, as well as long-term mortality. METHODS: In this retrospective cohort study, previously recruited 1,404 subjects were analyzed. The relationship between metformin use and delirium, and the relationship between metformin use and 3-year mortality were investigated. MAIN FINDINGS: 242 subjects were categorized into a type 2 diabetes mellitus (DM)-without-metformin group, and 264 subjects were categorized into a DM-with-metformin group. Prevalence of delirium was 36.0% in the DM-without-metformin group, and 29.2% in the DM-with-metformin group. A history of metformin use reduced the risk of delirium in patients with DM (OR, 0.50 [95% CI, 0.32 to 0.79]) after controlling for confounding factors. The 3-year mortality in the DM-without-metformin group (survival rate, 0.595 [95% CI, 0.512 to 0.669]) was higher than in the DM-with-metformin group (survival rate, 0.695 [95% CI, 0.604 to 0.770]) (p=0.035). A history of metformin use decreased the risk of 3-year mortality after adjustment for confounding factors (HR, 0.69 [95% CI, 0.48 to 0.98]). CONCLUSIONS: Metformin use may lower the risk of delirium and mortality in DM patients.


Assuntos
Delírio , Diabetes Mellitus Tipo 2 , Metformina , Humanos , Metformina/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Estudos Retrospectivos , Delírio/epidemiologia , Delírio/prevenção & controle , Fatores de Risco
7.
Neuroimage ; 262: 119584, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007822

RESUMO

The thalamus is a central integration structure in the brain, receiving and distributing information among the cerebral cortex, subcortical structures, and the peripheral nervous system. Prior studies clearly show that the thalamus atrophies in cognitively unimpaired aging. However, the thalamus is comprised of multiple nuclei involved in a wide range of functions, and the age-related atrophy of individual thalamic nuclei remains unknown. Using a recently developed automated method of identifying thalamic nuclei (3T or 7T MRI with white-matter-nulled MPRAGE contrast and THOMAS segmentation) and a cross-sectional design, we evaluated the age-related atrophy rate for 10 thalamic nuclei (AV, CM, VA, VLA, VLP, VPL, pulvinar, LGN, MGN, MD) and an epithalamic nucleus (habenula). We also used T1-weighted images with the FreeSurfer SAMSEG segmentation method to identify and measure age-related atrophy for 11 extra-thalamic structures (cerebral cortex, cerebral white matter, cerebellar cortex, cerebellar white matter, amygdala, hippocampus, caudate, putamen, nucleus accumbens, pallidum, and lateral ventricle). In 198 cognitively unimpaired participants with ages spanning 20-88 years, we found that the whole thalamus atrophied at a rate of 0.45% per year, and that thalamic nuclei had widely varying age-related atrophy rates, ranging from 0.06% to 1.18% per year. A functional grouping analysis revealed that the thalamic nuclei involved in cognitive (AV, MD; 0.53% atrophy per year), visual (LGN, pulvinar; 0.62% atrophy per year), and auditory/vestibular (MGN; 0.64% atrophy per year) functions atrophied at significantly higher rates than those involved in motor (VA, VLA, VLP, and CM; 0.37% atrophy per year) and somatosensory (VPL; 0.32% atrophy per year) functions. A proximity-to-CSF analysis showed that the group of thalamic nuclei situated immediately adjacent to CSF atrophied at a significantly greater atrophy rate (0.59% atrophy per year) than that of the group of nuclei located farther from CSF (0.36% atrophy per year), supporting a growing hypothesis that CSF-mediated factors contribute to neurodegeneration. We did not find any significant hemispheric differences in these rates of change for thalamic nuclei. Only the CM thalamic nucleus showed a sex-specific difference in atrophy rates, atrophying at a greater rate in male versus female participants. Roughly half of the thalamic nuclei showed greater atrophy than all extra-thalamic structures examined (0% to 0.54% per year). These results show the value of white-matter-nulled MPRAGE imaging and THOMAS segmentation for measuring distinct thalamic nuclei and for characterizing the high and heterogeneous atrophy rates of the thalamus and its nuclei across the adult lifespan. Collectively, these methods and results advance our understanding of the role of thalamic substructures in neurocognitive and disease-related changes that occur with aging.


Assuntos
Núcleos Talâmicos , Tálamo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Atrofia/patologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Núcleos Talâmicos/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/patologia , Adulto Jovem
8.
Neurobiol Aging ; 112: 151-160, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35182842

RESUMO

The entorhinal cortex is the site of some of the earliest pathological changes in Alzheimer's disease, including neuronal, synaptic and volumetric loss. Specifically, the lateral entorhinal cortex shows significant accumulation of tau neurofibrillary tangles in the amnestic mild cognitive impairment (aMCI) phase of Alzheimer's disease. Although decreased entorhinal cortex activation has been observed in patients with aMCI in the context of impaired memory function, it remains unclear if functional changes in the entorhinal cortex can be localized to the lateral or medial entorhinal cortex. To assess subregion specific changes in the lateral and medial entorhinal cortex, patients with aMCI and healthy aged-matched control participants underwent high-resolution structural and functional magnetic resonance imaging. Patients with aMCI showed significantly reduced volume, and decreased activation localized to the lateral entorhinal cortex but not the medial entorhinal cortex. These results show that structural and functional changes associated with impaired memory function differentially engage the lateral entorhinal cortex in patients with aMCI, consistent with the locus of early disease related pathology.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/patologia , Humanos , Imageamento por Ressonância Magnética , Transtornos da Memória/patologia
9.
Front Oncol ; 12: 966441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36741704

RESUMO

Anti-estrogens or aromatase inhibitors in combination with cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors are the current standard of care for estrogen receptor-positive (ER+) Her-2 negative metastatic breast cancer. Although these combination therapies prolong progression-free survival compared to endocrine therapy alone, the growth-arrested state of residual tumor cells is clearly transient. Tumor cells that escape what might be considered a dormant or quiescent state and regain proliferative capacity often acquire resistance to further therapies. Our studies are based upon the observation that breast tumor cells arrested by Fulvestrant + Palbociclib enter into states of both autophagy and senescence from which a subpopulation ultimately escapes, potentially contributing to recurrent disease. Autophagy inhibition utilizing pharmacologic or genetic approaches only moderately enhanced the response to Fulvestrant + Palbociclib in ER+ MCF-7 breast tumor cells, slightly delaying proliferative recovery. In contrast, the BET inhibitor/degrader, ARV-825, prolonged the growth arrested state in both p53 wild type MCF-7 cells and p53 mutant T-47D cells and significantly delayed proliferative recovery. In addition, ARV-825 added after the Fulvestrant + Palbociclib combination promoted apoptosis and demonstrated efficacy in resistant RB deficient cell lines. These studies indicate that administration of BET inhibitors/degraders, which are currently being investigated in multiple clinical trials, may potentially improve standard of care therapy in metastatic ER+ breast cancer patients and may further prolong progression-free survival.

10.
Ophthalmol Glaucoma ; 5(2): 188-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34389508

RESUMO

PURPOSE: To assess the accuracy and efficacy of deep learning models, specifically convolutional neural networks (CNNs), to identify glaucoma medication bottles. DESIGN: Algorithm development for predicting ophthalmic medication bottles using a large mobile image-based dataset. PARTICIPANTS: A total of 3750 mobile images of 5 ophthalmic medication bottles were included: brimonidine tartrate, dorzolamide-timolol, latanoprost, prednisolone acetate, and moxifloxacin. METHODS: Seven CNN models were initially pretrained on a large-scale image database and subsequently retrained to classify 5 commonly prescribed topical ophthalmic medications using a training dataset of 2250 mobile-phone captured images. The retrained CNN models' accuracies were compared using k-fold cross-validation (k = 10). The top 2 performing CNN models were then embedded into separate iOS apps and evaluated using 1500 mobile images not included in the training dataset. MAIN OUTCOME MEASURES: Prediction accuracy, image processing time. RESULTS: Of the 7 CNN architectures, MobileNet v2 yielded the highest k-fold cross-validation accuracy of 0.974 (95% confidence interval [CI], 0.966-0.980) and the shortest average image processing time at 3.45 (95% CI, 3.13-3.77) sec/image. ResNet V2 had the second highest accuracy of 0.961 (95% CI, 0.952-0.969). When the 2 app-embedded CNNs were compared, in terms of accuracy, MobileNet V2, with an image prediction accuracy of 0.86 (95% CI, 0.84-0.88), was significantly greater than ResNet V2, 0.68 (95% CI, 0.66-0.71) (Table 1). Sensitivities and specificities varied between medications (Table 1). There was no significant difference in average imaging processing time, 0.32 (95% CI, 0.28-0.36) sec/image and 0.31 (95% CI, 0.29-0.33) sec/image for MobileNet V2 and ResNet V2, respectively. Information on beta-testing of the iOS app can be found here: https://lin.hs.uci.edu/research/. CONCLUSIONS: We have retrained MobileNet V2 to accurately identify ophthalmic medication bottles and demonstrated that this neural network can operate in a smartphone environment. This work serves as a proof-of-concept for the production of a CNN-based smartphone application to empower patients by decreasing risk for error.


Assuntos
Aprendizado Profundo , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Smartphone
11.
J Med Internet Res ; 23(10): e25777, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34668872

RESUMO

BACKGROUND: Integrated community case management (CCM) has led to reductions in child mortality in Malawi resulting from illnesses such as malaria, pneumonia, and diarrhea. However, adherence to CCM guidelines is often poor, potentially leading to inappropriate clinical decisions and poor outcomes. We determined the impact of an e-CCM app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi. OBJECTIVE: We determined the impact of an electronic version of a smartphone-based CCM (e-CCM) app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi. METHODS: We used a stepped-wedge, cluster-randomized trial to compare paper-based CCM (control) with and without the use of an e-CCM app on smartphones from November 2016 to February 2017. A total of 102 village clinics from 2 districts in northern Malawi were assigned to 1 of 6 clusters, which were randomized on the sequencing of the crossover from the control phase to the intervention phase as well as the duration of exposure in each phase. Children aged ≥2 months to <5 years who presented with acute illness were enrolled consecutively by health surveillance assistants. The primary outcome of urgent referrals to higher-level facilities was evaluated by using multilevel mixed effects models. A logistic regression model with the random effects of the cluster and the fixed effects for each step was fitted. The adjustment for potential confounders included baseline factors, such as patient age, sex, and the geographical location of the village clinics. Calendar time was adjusted for in the analysis. RESULTS: A total of 6965 children were recruited-49.11% (3421/6965) in the control phase and 50.88% (3544/6965) in the intervention phase. After adjusting for calendar time, children in the intervention phase were more likely to be urgently referred to a higher-level health facility than children in the control phase (odds ratio [OR] 2.02, 95% CI 1.27-3.23; P=.003). Overall, children in the intervention arm had lower odds of attending a repeat health surveillance assistant consultation (OR 0.45, 95% CI 0.34-0.59; P<.001) or being admitted to a hospital (OR 0.75, 95% CI 0.62-0.90; P=.002), but after adjusting for time, these differences were not significant (P=.07 for consultation; P=.30 for hospital admission). CONCLUSIONS: The addition of e-CCM decision support by using smartphones led to a greater proportion of children being referred to higher-level facilities, with no apparent increase in hospital admissions or repeat consultations in village clinics. Our findings provide support for the implementation of e-CCM tools in Malawi and other low- and middle-income countries with a need for ongoing assessments of effectiveness and integration with national digital health strategies. TRIAL REGISTRATION: ClinicalTrials.gov NCT02763345; https://clinicaltrials.gov/ct2/show/NCT02763345.


Assuntos
Administração de Caso , Smartphone , Criança , Hospitalização , Humanos , Malaui , Encaminhamento e Consulta
12.
Learn Mem ; 28(7): 239-247, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34131055

RESUMO

There has been considerable focus on investigating age-related memory changes in cognitively healthy older adults, in the absence of neurodegenerative disorders. Previous studies have reported age-related domain-specific changes in older adults, showing increased difficulty encoding and processing object information but minimal to no impairment in processing spatial information compared with younger adults. However, few of these studies have examined age-related changes in the encoding of concurrently presented object and spatial stimuli, specifically the integration of both spatial and nonspatial (object) information. To more closely resemble real-life memory encoding and the integration of both spatial and nonspatial information, the current study developed a new experimental paradigm with novel environments that allowed for the placement of different objects in different positions within the environment. The results show that older adults have decreased performance in recognizing changes of the object position within the spatial context but no significant differences in recognizing changes in the identity of the object within the spatial context compared with younger adults. These findings suggest there may be potential age-related differences in the mechanisms underlying the representations of complex environments and furthermore, the integration of spatial and nonspatial information may be differentially processed relative to independent and isolated representations of object and spatial information.


Assuntos
Envelhecimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção Espacial/fisiologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Eur J Pain ; 25(6): 1367-1380, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33675555

RESUMO

BACKGROUND: Although paclitaxel is an effective chemotherapeutic agent used to treat multiple types of cancer (e.g. breast, ovarian, neck and lung), it also elicits paclitaxel-induced peripheral neuropathy (PIPN), which represents a major dose-limiting side effect of this drug. METHODS: As the endogenously produced N-acylethanolamine, palmitoylethanolamide (PEA), reverses paclitaxel-induced mechanical hypersensitivity in mice, the main goals of this study were to examine if paclitaxel affects levels of endogenous PEA in the spinal cord of mice and whether exogenous administration of PEA provides protection from the occurrence of paclitaxel-induced mechanical hypersensitivity. We further examined whether inhibition of N-acylethanolamine-hydrolysing acid amidase (NAAA), a hydrolytic PEA enzyme, would offer protection in mouse model of PIPN. RESULTS: Paclitaxel reduced PEA levels in the spinal cord, suggesting that dysregulation of this lipid signalling system may contribute to PIPN. Consistent with this idea, repeated administration of PEA partially prevented the paclitaxel-induced mechanical hypersensitivity. We next evaluated whether the selective NAAA inhibitor, AM9053, would prevent paclitaxel-induced mechanical hypersensitivity in mice. Acute administration of AM9053 dose-dependently reversed mechanical hypersensitivity through a PPAR-α mechanism, whereas repeated administration of AM9053 fully prevented the development of PIPN, without any evidence of tolerance. Moreover, AM9053 produced a conditioned place preference in paclitaxel-treated mice, but not in control mice. This pattern of findings suggests a lack of intrinsic rewarding effects, but a reduction in the pain aversiveness induced by paclitaxel. Finally, AM9053 did not alter paclitaxel-induced cytotoxicity in lung tumour cells. CONCLUSIONS: Collectively, these studies suggest that NAAA represents a promising target to treat and prevent PIPN. SIGNIFICANCE: The present study demonstrates that the chemotherapeutic paclitaxel alters PEA levels in the spinal cord, whereas repeated exogenous PEA administration moderately alleviates PIPN in mice. Additionally, targeting NAAA, PEA's hydrolysing enzyme with a selective compound AM9053 reverses and prevents the PIPN via the PPAR-α mechanism. Overall, the data suggest that selective NAAA inhibitors denote promising future therapeutics to mitigate and prevent PIPN.


Assuntos
Paclitaxel , Doenças do Sistema Nervoso Periférico , Amidoidrolases , Animais , Etanolaminas , Camundongos , PPAR alfa , Paclitaxel/toxicidade
14.
Brain Behav Immun ; 93: 172-185, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33434562

RESUMO

BACKGROUND AND PURPOSE: Paclitaxel, a widely used anti-cancer drug, is frequently associated with prolonged and severe peripheral neuropathies (PIPN), associated with neuroinflammation. Currently, PIPN effective treatments are lacking. Peroxisome Proliferator-Activated Receptor-α (PPAR-⍺) can modulate inflammatory responses. Thus, the use of PPAR-⍺ agonists, such as fibrates (fenofibrate and choline-fenofibrate), currently used in dyslipidemia treatment, could represent an interesting therapeutic approach in PIPN. EXPERIMENTAL APPROACH: Our studies tested the efficacy of fenofibrate (150 mg/kg, daily, i.p.) and choline fenofibrate (60 mg/kg daily, p.o.) in reversing and preventing the development of PIPN (paclitaxel: 8 mg/kg, i.p., every other day for 4 days) in male and female C57BL/6J mice. Mechanical and cold hypersensitivity, conditioned place preference, sensory nerve action potential (SNAP), as well as the expression of PPAR-⍺, TNF-⍺, IL-1ß and IL-6 mRNA were evaluated. KEY RESULTS: While fenofibrate treatment partially reversed and prevented the development of mechanical hypersensitivity, this was completely reversed and prevented by choline-fenofibrate. Both fibrates were able to completely reverse and prevent cold hypersensitivity induced by paclitaxel. The reduction of SNAP amplitude induced by paclitaxel was also reversed by both fenofibrate and choline-fenofibrate. Our results indicate that suppression of paclitaxel-induced hypersensitivity by fibrates involves the regulation of PPAR-⍺ expression and decrease neuroinflammation in DRG. Finally, the co-treatment of Paclitaxel and fenofibric acid (fibrates active metabolite) was tested on different cancer cell lines, no decrease in the antitumoral effect of paclitaxel was observed. CONCLUSIONS AND IMPLICATIONS: Taken together, our results show for the first time the therapeutic potential (prevention and reversal) of fibrates in PIPN and opens to a potential pharmacological repurposing of these drugs.


Assuntos
PPAR alfa , Doenças do Sistema Nervoso Periférico , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Paclitaxel , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico
15.
Neurology ; 96(10): e1470-e1481, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33408146

RESUMO

OBJECTIVE: To determine whether memory tasks with demonstrated sensitivity to hippocampal function can detect variance related to preclinical Alzheimer disease (AD) biomarkers, we examined associations between performance in 3 memory tasks and CSF ß-amyloid (Aß)42/Aß40 and phosopho-tau181 (p-tau181) in cognitively unimpaired older adults (CU). METHODS: CU enrolled in the Stanford Aging and Memory Study (n = 153; age 68.78 ± 5.81 years; 94 female) completed a lumbar puncture and memory assessments. CSF Aß42, Aß40, and p-tau181 were measured with the automated Lumipulse G system in a single-batch analysis. Episodic memory was assayed using a standardized delayed recall composite, paired associate (word-picture) cued recall, and a mnemonic discrimination task that involves discrimination between studied "target" objects, novel "foil" objects, and perceptually similar "lure" objects. Analyses examined cross-sectional relationships among memory performance, age, and CSF measures, controlling for sex and education. RESULTS: Age and lower Aß42/Aß40 were independently associated with elevated p-tau181. Age, Aß42/Aß40, and p-tau181 were each associated with (1) poorer associative memory and (2) diminished improvement in mnemonic discrimination performance across levels of decreased task difficulty (i.e., target-lure similarity). P-tau mediated the effect of Aß42/Aß40 on memory. Relationships between CSF proteins and delayed recall were similar but nonsignificant. CSF Aß42 was not significantly associated with p-tau181 or memory. CONCLUSIONS: Tests designed to tax hippocampal function are sensitive to subtle individual differences in memory among CU and correlate with early AD-associated biomarker changes in CSF. These tests may offer utility for identifying CU with preclinical AD pathology.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Hipocampo/fisiopatologia , Transtornos da Memória/líquido cefalorraquidiano , Transtornos da Memória/psicologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Aprendizagem por Associação , Estudos Transversais , Sinais (Psicologia) , Discriminação Psicológica , Feminino , Humanos , Masculino , Memória , Transtornos da Memória/fisiopatologia , Memória Episódica , Rememoração Mental , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fragmentos de Peptídeos/líquido cefalorraquidiano , Desempenho Psicomotor , Proteínas tau/líquido cefalorraquidiano
16.
Br J Psychiatry ; : 1-8, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35049468

RESUMO

BACKGROUND: We have developed the bispectral electroencephalography (BSEEG) method for detection of delirium and prediction of poor outcomes. AIMS: To improve the BSEEG method by introducing a new EEG device. METHOD: In a prospective cohort study, EEG data were obtained and BSEEG scores were calculated. BSEEG scores were filtered on the basis of standard deviation (s.d.) values to exclude signals with high noise. Both non-filtered and s.d.-filtered BSEEG scores were analysed. BSEEG scores were compared with the results of three delirium screening scales: the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU), the Delirium Rating Scale-Revised-98 (DRS) and the Delirium Observation Screening Scale (DOSS). Additionally, the 365-day mortalities and the length of stay (LOS) in the hospital were analysed. RESULTS: We enrolled 279 elderly participants and obtained 620 BSEEG recordings; 142 participants were categorised as BSEEG-positive, reflecting slower EEG activity. BSEEG scores were higher in the CAM-ICU-positive group than in the CAM-ICU-negative group. There were significant correlations between BSEEG scores and scores on the DRS and the DOSS. The mortality rate of the BSEEG-positive group was significantly higher than that of the BSEEG-negative group. The LOS of the BSEEG-positive group was longer compared with that of the BSEEG-negative group. BSEEG scores after s.d. filtering showed stronger correlations with delirium screening scores and more significant prediction of mortality. CONCLUSIONS: We confirmed the usefulness of the BSEEG method for detection of delirium and of delirium severity, and prediction of patient outcomes with a new EEG device.

17.
Alzheimers Dement (Amst) ; 12(1): e12043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32775595

RESUMO

INTRODUCTION: Recent studies have suggested that sex confers a differential risk in the incidence and prevalence of Alzheimer's disease (AD) thought to be the result of the increased lifespan of women compared to men. However, other factors may contribute to risk beyond the effect of increased lifespan. METHODS: This study examined the role of sex in hippocampal hyperactivity localized to the dentate gyrus (DG)/CA3 subregion of the hippocampus and associated episodic memory impairment, considered a characteristic feature of AD in patients with amnestic mild cognitive impairment (aMCI). RESULTS: While participants with aMCI showed decreased memory performance and increased activation in the DG/CA3 when compared to controls, no significant sex-related differences in performance or activation were observed. DISCUSSION: Although other factors may contribute to sex differences in the prevalence of AD these findings show that no sex differences are observed in hippocampal dysfunction characteristic of the aMCI phase of AD.

18.
Cancers (Basel) ; 13(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383736

RESUMO

BACKGROUND: Paclitaxel-induced peripheral neuropathy (PIPN) is a major adverse effect of this chemotherapeutic agent that is used in the treatment of a number of solid malignancies. PIPN leads notably to burning pain, cold and mechanical allodynia. PIPN is thought to be a consequence of alterations of mitochondrial function, hyperexcitability of neurons, nerve fiber loss, oxidative stress and neuroinflammation in dorsal root ganglia (DRG) and spinal cord (SC). Therefore, reducing neuroinflammation could potentially attenuate neuropathy symptoms. Peroxisome proliferator-activated receptor-α (PPAR-α) nuclear receptors that modulate inflammatory responses can be targeted by non-selective agonists, such as fenofibrate, which is used in the treatment of dyslipidemia. METHODS: Our studies tested the efficacy of a fenofibrate diet (0.2% and 0.4%) in preventing the development of PIPN. Paclitaxel (8 mg/kg) was administered via 4 intraperitoneal (i.p.) injections in C57BL/6J mice (both male and female). Mechanical and cold hypersensitivity, wheel running activity, sensory nerve action potential (SNAP), sciatic nerve histology, intra-epidermal fibers, as well as the expression of PPAR-α and neuroinflammation were evaluated in DRG and SC. RESULTS: Fenofibrate in the diet partially prevented the development of mechanical hypersensitivity but completely prevented cold hypersensitivity and the decrease in wheel running activity induced by paclitaxel. The reduction in SNAP amplitude induced by paclitaxel was also prevented by fenofibrate. Our results indicate that suppression of paclitaxel-induced pain by fenofibrate involves the regulation of PPAR-α expression through reduction in neuroinflammation. Finally, co-administration of paclitaxel and the active metabolite of fenofibrate (fenofibric acid) did not interfere with the suppression of tumor cell growth or clonogenicity by paclitaxel in ovarian and breast cancer cell lines. CONCLUSIONS: Taken together, our results show the therapeutic potential of fenofibrate in the prevention of PIPN development.

19.
Malawi Med J ; 31(3): 177-183, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31839886

RESUMO

Background: The global health community and funding agencies are currently engaged in ensuring that worthwhile research-based programmes are sustainable. Despite its importance, few studies have analysed the sustainability of global health interventions. In this paper, we aim to explore barriers and facilitators for the wider implementation and sustainability of a mobile health (mHealth) intervention (Supporting LIFE Community Case Management programme) in Malawi, Africa. Methods: Between January and March 2017, a qualitative approach was used to carry out and analyse 13 in-depth semi-structured interviews with key stakeholders across all levels of healthcare provision in Malawi to explore their perceptions with regards to the implementation and sustainability of the mHealth programme. Data were analysed thematically by two reviewers. Results: Overall, our analysis found that the programme was successful in achieving its goals. However, there are many challenges to the wider implementation and sustainability of this programme, including the absence of monetary resources, limited visibility outside the healthcare sector, the lack of integration with community-based and nationwide programmes, services and information and communication technologies, and the limited local capacity in relation to the maintenance, further development, and management. Conclusions: Future developments should be aligned with the strategic goals and interests of the Ministry of Health and engage with national and international stakeholders to develop shared goals and strategies for nationwide scale-up. These developments should also focus on building local capacity by educating trainers and ensuring that training methods and guidelines are appropriately accredited based on national policies. Our findings provide a framework for a variety of stakeholders who are engaged in sustaining mHealth programmes in resource-poor settings and can be used to develop an evidence-based policy for the utilization of technology for healthcare delivery across developing countries.


Assuntos
Administração de Caso/organização & administração , Atenção à Saúde/organização & administração , Avaliação de Programas e Projetos de Saúde , Telemedicina/organização & administração , Participação da Comunidade , Atenção à Saúde/métodos , Humanos , Entrevistas como Assunto , Malaui , Pesquisa Qualitativa
20.
Sci Rep ; 9(1): 10669, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337818

RESUMO

The process of mitochondrial fission-fusion has been implicated in diverse neuronal roles including neuronal survival, axon degeneration, and axon regeneration. However, whether increased fission or fusion is beneficial for neuronal health and/or axonal growth is not entirely clear, and is likely situational and cell type-dependent. In searching for mitochondrial fission-fusion regulating proteins for improving axonal growth within the visual system, we uncover that mitochondrial fission process 1,18 kDa (MTP18/MTFP1), a pro-fission protein within the CNS, is critical to maintaining mitochondrial size and volume under normal and injury conditions, in retinal ganglion cells (RGCs). We demonstrate that MTP18's expression is regulated by transcription factors involved in axonal growth, Kruppel-like factor (KLF) transcription factors-7 and -9, and that knockdown of MTP18 promotes axon growth. This investigation exposes MTP18's previously unexplored role in regulating mitochondrial fission, implicates MTP18 as a downstream component of axon regenerative signaling, and ultimately lays the groundwork for investigations on the therapeutic efficacy of MTP18 expression suppression during CNS axon degenerative events.


Assuntos
Axônios/metabolismo , Proteínas de Membrana/metabolismo , Dinâmica Mitocondrial/fisiologia , Proteínas Mitocondriais/metabolismo , Regeneração Nervosa/fisiologia , Neurônios/metabolismo , Animais , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Compressão Nervosa , Crescimento Neuronal/fisiologia , Traumatismos do Nervo Óptico/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
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