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1.
Nat Med ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760585

RESUMEN

Neural-tumor interactions drive glioma growth as evidenced in preclinical models, but clinical validation is limited. We present an epigenetically defined neural signature of glioblastoma that independently predicts patients' survival. We use reference signatures of neural cells to deconvolve tumor DNA and classify samples into low- or high-neural tumors. High-neural glioblastomas exhibit hypomethylated CpG sites and upregulation of genes associated with synaptic integration. Single-cell transcriptomic analysis reveals a high abundance of malignant stemcell-like cells in high-neural glioblastoma, primarily of the neural lineage. These cells are further classified as neural-progenitor-cell-like, astrocyte-like and oligodendrocyte-progenitor-like, alongside oligodendrocytes and excitatory neurons. In line with these findings, high-neural glioblastoma cells engender neuron-to-glioma synapse formation in vitro and in vivo and show an unfavorable survival after xenografting. In patients, a high-neural signature is associated with decreased overall and progression-free survival. High-neural tumors also exhibit increased functional connectivity in magnetencephalography and resting-state magnet resonance imaging and can be detected via DNA analytes and brain-derived neurotrophic factor in patients' plasma. The prognostic importance of the neural signature was further validated in patients diagnosed with diffuse midline glioma. Our study presents an epigenetically defined malignant neural signature in high-grade gliomas that is prognostically relevant. High-neural gliomas likely require a maximized surgical resection approach for improved outcomes.

2.
bioRxiv ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38798554

RESUMEN

Persistent central nervous system (CNS) immune dysregulation and consequent dysfunction of multiple neural cell types is central to the neurobiological underpinnings of a cognitive impairment syndrome that can occur following traditional cancer therapies or certain infections. Immunotherapies have revolutionized cancer care for many tumor types, but the potential long-term cognitive sequelae are incompletely understood. Here, we demonstrate in mouse models that chimeric antigen receptor (CAR) T cell therapy for both CNS and non-CNS cancers can impair cognitive function and induce a persistent CNS immune response characterized by white matter microglial reactivity and elevated cerebrospinal fluid (CSF) cytokines and chemokines. Consequently, oligodendroglial homeostasis and hippocampal neurogenesis are disrupted. Microglial depletion rescues oligodendroglial deficits and cognitive performance in a behavioral test of attention and short-term memory function. Taken together, these findings illustrate similar mechanisms underlying immunotherapy-related cognitive impairment (IRCI) and cognitive impairment following traditional cancer therapies and other immune challenges.

3.
Eur J Clin Microbiol Infect Dis ; 43(2): 249-257, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38030860

RESUMEN

PURPOSE: The objective of this multicenter study was to compare the diagnostic performance of lateral flow assay (LFA) and enzyme-linked immunosorbent assay (ELISA) to detect the Dynamiker Aspergillus Galactomannan levels in serum and bronchoalveolar lavage fluid (BALF) samples for I. METHODS: We registered 310 clinically suspected Aspergillus infection patients from December 2021 to February 2023 and classified them into subgroups as the "IA group" and "non-IA group" based on the latest EORTC/MSG guidelines. The immunoassays were analyzed by LFA and ELISA respectively. RESULTS: Galactomannan was examined using LFA, and serum and BALF samples demonstrated sensitivities of 82.57% and 89.47%, specificities of 90.76% and 92.00%, PPVs of 89.11% and 96.23%, and NPVs of 85.04% and 79.31%, respectively. Galactomannan was observed using two assays in serum and BALF samples and showed PPAs of 95.11% and 93.33%, NPAs of 89.19% and 96.30%, and TPAs of 92.47% and 94.25%, respectively. The ROC curve demonstrated that LFA had optimum diagnostic value when the index value (I value) = 0.5, the sensitivity was 84.94%, and the specificity was 90.97%. CONCLUSION: Compared to the ELISA method, the LFA has shown excellent performance for the diagnosis of IA in serum and BALF sample and can be used as an assay for the early diagnosis of patients with IA. The dynamic change in galactomannan levels may be useful for assessing treatment response.


Asunto(s)
Aspergilosis , Galactosa/análogos & derivados , Infecciones Fúngicas Invasoras , Humanos , Sensibilidad y Especificidad , Aspergilosis/diagnóstico , Aspergillus , Mananos/análisis , Líquido del Lavado Bronquioalveolar/microbiología
4.
Nature ; 623(7986): 366-374, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37914930

RESUMEN

The role of the nervous system in the regulation of cancer is increasingly appreciated. In gliomas, neuronal activity drives tumour progression through paracrine signalling factors such as neuroligin-3 and brain-derived neurotrophic factor1-3 (BDNF), and also through electrophysiologically functional neuron-to-glioma synapses mediated by AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors4,5. The consequent glioma cell membrane depolarization drives tumour proliferation4,6. In the healthy brain, activity-regulated secretion of BDNF promotes adaptive plasticity of synaptic connectivity7,8 and strength9-15. Here we show that malignant synapses exhibit similar plasticity regulated by BDNF. Signalling through the receptor tropomyosin-related kinase B16 (TrkB) to CAMKII, BDNF promotes AMPA receptor trafficking to the glioma cell membrane, resulting in increased amplitude of glutamate-evoked currents in the malignant cells. Linking plasticity of glioma synaptic strength to tumour growth, graded optogenetic control of glioma membrane potential demonstrates that greater depolarizing current amplitude promotes increased glioma proliferation. This potentiation of malignant synaptic strength shares mechanistic features with synaptic plasticity17-22 that contributes to memory and learning in the healthy brain23-26. BDNF-TrkB signalling also regulates the number of neuron-to-glioma synapses. Abrogation of activity-regulated BDNF secretion from the brain microenvironment or loss of glioma TrkB expression robustly inhibits tumour progression. Blocking TrkB genetically or pharmacologically abrogates these effects of BDNF on glioma synapses and substantially prolongs survival in xenograft models of paediatric glioblastoma and diffuse intrinsic pontine glioma. Together, these findings indicate that BDNF-TrkB signalling promotes malignant synaptic plasticity and augments tumour progression.


Asunto(s)
Adaptación Fisiológica , Glioma , Plasticidad Neuronal , Sinapsis , Animales , Niño , Humanos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proliferación Celular , Progresión de la Enfermedad , Glioma/metabolismo , Glioma/patología , Ácido Glutámico/metabolismo , Neuronas/citología , Neuronas/metabolismo , Receptor trkB/genética , Receptor trkB/metabolismo , Receptores AMPA/metabolismo , Transducción de Señal , Sinapsis/metabolismo , Microambiente Tumoral , Optogenética
5.
bioRxiv ; 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37609137

RESUMEN

Neural-tumor interactions drive glioma growth as evidenced in preclinical models, but clinical validation is nascent. We present an epigenetically defined neural signature of glioblastoma that independently affects patients' survival. We use reference signatures of neural cells to deconvolve tumor DNA and classify samples into low- or high-neural tumors. High-neural glioblastomas exhibit hypomethylated CpG sites and upregulation of genes associated with synaptic integration. Single-cell transcriptomic analysis reveals high abundance of stem cell-like malignant cells classified as oligodendrocyte precursor and neural precursor cell-like in high-neural glioblastoma. High-neural glioblastoma cells engender neuron-to-glioma synapse formation in vitro and in vivo and show an unfavorable survival after xenografting. In patients, a high-neural signature associates with decreased survival as well as increased functional connectivity and can be detected via DNA analytes and brain-derived neurotrophic factor in plasma. Our study presents an epigenetically defined malignant neural signature in high-grade gliomas that is prognostically relevant.

6.
Neuroimage ; 280: 120312, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37574120

RESUMEN

Activity-dependent myelination is a fundamental mode of brain plasticity which significantly influences network function. We recently discovered that absence seizures, which occur in multiple forms of generalized epilepsy, can induce activity-dependent myelination, which in turn promotes further progression of epilepsy. Structural alterations of myelin are likely to be widespread, given that absence seizures arise from an extensive thalamocortical network involving frontoparietal regions of the bilateral hemispheres. However, the temporal course and spatial extent of myelin plasticity is unknown, due to limitations of gold-standard histological methods such as electron microscopy (EM). In this study, we leveraged magnetization transfer and diffusion MRI for estimation of g-ratios across major white matter tracts in a mouse model of generalized epilepsy with progressive absence seizures. EM was performed on the same brains after MRI. After seizure progression, we found increased myelination (decreased g-ratios) throughout the anterior portion (genu-to-body) of the corpus callosum but not in the posterior portion (body-splenium) nor in the fornix or the internal capsule. Curves obtained from averaging g-ratio values at every longitudinal point of the corpus callosum were statistically different with p<0.001. Seizure-associated myelin differences found in the corpus callosum body with MRI were statistically significant (p = 0.0027) and were concordant with EM in the same region (p = 0.01). Notably, these differences were not detected by diffusion tensor imaging. This study reveals widespread myelin structural change that is specific to the absence seizure network. Furthermore, our findings demonstrate the potential utility and importance of MRI-based g-ratio estimation to non-invasively detect myelin plasticity.


Asunto(s)
Imagen de Difusión Tensora , Epilepsia Generalizada , Animales , Ratones , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cuerpo Calloso/patología , Convulsiones/diagnóstico por imagen
7.
Nature ; 617(7961): 599-607, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37138086

RESUMEN

Gliomas synaptically integrate into neural circuits1,2. Previous research has demonstrated bidirectional interactions between neurons and glioma cells, with neuronal activity driving glioma growth1-4 and gliomas increasing neuronal excitability2,5-8. Here we sought to determine how glioma-induced neuronal changes influence neural circuits underlying cognition and whether these interactions influence patient survival. Using intracranial brain recordings during lexical retrieval language tasks in awake humans together with site-specific tumour tissue biopsies and cell biology experiments, we find that gliomas remodel functional neural circuitry such that task-relevant neural responses activate tumour-infiltrated cortex well beyond the cortical regions that are normally recruited in the healthy brain. Site-directed biopsies from regions within the tumour that exhibit high functional connectivity between the tumour and the rest of the brain are enriched for a glioblastoma subpopulation that exhibits a distinct synaptogenic and neuronotrophic phenotype. Tumour cells from functionally connected regions secrete the synaptogenic factor thrombospondin-1, which contributes to the differential neuron-glioma interactions observed in functionally connected tumour regions compared with tumour regions with less functional connectivity. Pharmacological inhibition of thrombospondin-1 using the FDA-approved drug gabapentin decreases glioblastoma proliferation. The degree of functional connectivity between glioblastoma and the normal brain negatively affects both patient survival and performance in language tasks. These data demonstrate that high-grade gliomas functionally remodel neural circuits in the human brain, which both promotes tumour progression and impairs cognition.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Vías Nerviosas , Humanos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patología , Trombospondina 1/antagonistas & inhibidores , Gabapentina/farmacología , Gabapentina/uso terapéutico , Progresión de la Enfermedad , Cognición , Tasa de Supervivencia , Vigilia , Biopsia , Proliferación Celular/efectos de los fármacos
8.
Infect Drug Resist ; 16: 1039-1048, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36845019

RESUMEN

Purpose: To investigate whether rapid active molecular screening and infection prevention and control (IPC) interventions can reduce colonization or infection with carbapenem-resistant Enterobacterales (CRE) in a general emergency intensive care unit (EICU) without enough single-room isolation. Methods: The study was designed as a before-and-after quasi-experiment. Before the experimental period, the ward was rescheduled and the staff were trained. From May 2018 to April 2021, active screening was performed by seminested real-time fluorescent polymerase chain reaction (PCR) detection with rectal swabs from all patients on admission to the EICU, and the results were reported in 1 hour. Other IPC interventions including hand hygiene, contact precautions, patient isolation, environmental disinfection, environment surveillance, monitoring, auditing and feedback were conducted under strict supervision. The patients' clinical characteristics were collected simultaneously. Results: In this 3-year study, 630 patients were enrolled and 19.84% of the patients were initially colonized or infected with CRE as shown by active molecular screening. The average drug resistance ratio to carbapenem shown by clinical culture detection of Klebsiella pneumoniae (KPN) before the study was performed was 71.43% in EICU. The drug resistance ratio decreased significantly from 75%, 66.67% to 46.67% in the next 3 years (p<0.05) during which active screening and IPC interventions were strictly executed. While the ratio gaps between EICU and the whole hospital were narrowed from 22.81%, 21.11% to 4.64%. Patients with invasive devices, skin barrier damage, and the recent use of antibiotics on admission were found to have a higher risk of being colonized or infected with CRE (p<0.05). Conclusion: Active rapid molecular screening and other IPC interventions may significantly reduce CRE nosocomial infections even in wards without enough single-room isolation. The key to reduce the spread of CRE in the EICU is the strict execution of IPC interventions by all medical staff and healthcare workers.

9.
Infect Drug Resist ; 16: 913-921, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36814830

RESUMEN

Purpose: Matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MALDI-TOF) has recently been widely used in clinical microbiology laboratories, with the advantages of being reliable, rapid, and cost-effective. Here, we reported the performance of two MALDI-TOF MS instruments, EXS3000 (Zybio, China) and Autof ms1000 (Autobio, China), which are commonly used in clinical microbiology field. Methods: A total of 209 common clinical common isolates, including 70 gram-negative bacteria strains, 58 gram-positive bacteria strains, 33 yeast strains, 15 anaerobic bacteria strains, and 33 mold strains, and 19 mycobacterial strains were tested. All strains were identified by EXS3000 (Zybio, China) and Autof ms1000 (Autobio, China). Sequence analysis of 16S rRNA or ITS regions was used to verify all strains. Results: Current study found that species-level discrimination was found to be 191 (91.39%) and 190 (90.91%) by EXS3000 and Autof ms1000, respectively. Genus-level discrimination was 205 (98.09%) by the EXS3000 and 205 (98.09%) by the Autof ms1000, respectively. The correct results at species level of the EXS3000 were 91.43% (64/70) for gram-negative bacteria, 93.1% (54/58) for gram-positive cocci, 93.94% (31/33) for yeast, 100% (15/15) for anaerobes and 81.82% (27/33) for filamentous fungi. The correct results at species level of the Autof ms1000 were 92.86% (65/70) for gram-negative bacteria, 91.38% (53/58) for gram-positive cocci, 93.94% (31/33) for yeast, 100% (15/15) for anaerobes and 78.79% (26/33) for filamentous fungi. Conclusion: Although the results show that the EXS3000 and Autof ms1000 systems are equally good choices in terms of analytical efficiency for routine procedures, the test result of EXS3000 is slightly better than Autof ms1000. It's worth mentioning that the target plate of the EXS 3000 instrument is reusable, but the target plate of the Autof ms1000 is disposable, making the EXS3000 more effective in reducing costs.

10.
Sensors (Basel) ; 23(2)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36679780

RESUMEN

Aiming at guiding agricultural producers to harvest crops at an appropriate time and ensuring the pesticide residue does not exceed the maximum limit, the present work proposed a method of detecting pesticide residue rapidly by analyzing near-infrared microscopic images of the leaves of Shanghaiqing (Brassica rapa), a type of Chinese cabbage with computer vision technology. After image pre-processing and feature extraction, the pattern recognition methods of K nearest neighbors (KNN), naïve Bayes, support vector machine (SVM), and back propagation artificial neural network (BP-ANN) were applied to assess whether Shanghaiqing is sprayed with pesticides. The SVM method with linear or RBF kernel provides the highest recognition accuracy of 96.96% for the samples sprayed with trichlorfon at a concentration of 1 g/L. The SVM method with RBF kernel has the highest recognition accuracy of 79.16~84.37% for the samples sprayed with cypermethrin at a concentration of 0.1 g/L. The investigation on the SVM classification models built on the samples sprayed with cypermethrin at different concentrations shows that the accuracy of the models increases with the pesticide concentrations. In addition, the relationship between the concentration of the cypermethrin sprayed and the image features was established by multiple regression to estimate the initial pesticide concentration on the Shanghaiqing leaves. A pesticide degradation equation was established on the basis of the first-order kinetic equation. The time for pesticides concentration to decrease to an acceptable level can be calculated on the basis of the degradation equation and the initial pesticide concentration. The present work provides a feasible way to rapidly detect pesticide residue on Shanghaiqing by means of NIR microscopic image technique. The methodology laid out in this research can be used as a reference for the pesticide detection of other types of vegetables.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Residuos de Plaguicidas/análisis , Teorema de Bayes , Verduras/química
11.
Cell ; 185(14): 2452-2468.e16, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35768006

RESUMEN

COVID survivors frequently experience lingering neurological symptoms that resemble cancer-therapy-related cognitive impairment, a syndrome for which white matter microglial reactivity and consequent neural dysregulation is central. Here, we explored the neurobiological effects of respiratory SARS-CoV-2 infection and found white-matter-selective microglial reactivity in mice and humans. Following mild respiratory COVID in mice, persistently impaired hippocampal neurogenesis, decreased oligodendrocytes, and myelin loss were evident together with elevated CSF cytokines/chemokines including CCL11. Systemic CCL11 administration specifically caused hippocampal microglial reactivity and impaired neurogenesis. Concordantly, humans with lasting cognitive symptoms post-COVID exhibit elevated CCL11 levels. Compared with SARS-CoV-2, mild respiratory influenza in mice caused similar patterns of white-matter-selective microglial reactivity, oligodendrocyte loss, impaired neurogenesis, and elevated CCL11 at early time points, but after influenza, only elevated CCL11 and hippocampal pathology persisted. These findings illustrate similar neuropathophysiology after cancer therapy and respiratory SARS-CoV-2 infection which may contribute to cognitive impairment following even mild COVID.


Asunto(s)
COVID-19 , Gripe Humana , Neoplasias , Animales , Humanos , Gripe Humana/patología , Ratones , Microglía/patología , Vaina de Mielina , Neoplasias/patología , SARS-CoV-2
12.
Nat Neurosci ; 25(5): 596-606, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35501379

RESUMEN

Activity-dependent myelination can fine-tune neural network dynamics. Conversely, aberrant neuronal activity, as occurs in disorders of recurrent seizures (epilepsy), could promote maladaptive myelination, contributing to pathogenesis. In this study, we tested the hypothesis that activity-dependent myelination resulting from absence seizures, which manifest as frequent behavioral arrests with generalized electroencephalography (EEG) spike-wave discharges, promote thalamocortical network hypersynchrony and contribute to epilepsy progression. We found increased oligodendrogenesis and myelination specifically within the seizure network in two models of generalized epilepsy with absence seizures (Wag/Rij rats and Scn8a+/mut mice), evident only after epilepsy onset. Aberrant myelination was prevented by pharmacological seizure inhibition in Wag/Rij rats. Blocking activity-dependent myelination decreased seizure burden over time and reduced ictal synchrony as assessed by EEG coherence. These findings indicate that activity-dependent myelination driven by absence seizures contributes to epilepsy progression; maladaptive myelination may be pathogenic in some forms of epilepsy and other neurological diseases.


Asunto(s)
Epilepsia Tipo Ausencia , Epilepsia Generalizada , Animales , Modelos Animales de Enfermedad , Electroencefalografía , Epilepsia Generalizada/genética , Ratones , Canal de Sodio Activado por Voltaje NAV1.6 , Ratas , Ratas Wistar , Convulsiones
13.
bioRxiv ; 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35043113

RESUMEN

Survivors of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection frequently experience lingering neurological symptoms, including impairment in attention, concentration, speed of information processing and memory. This long-COVID cognitive syndrome shares many features with the syndrome of cancer therapy-related cognitive impairment (CRCI). Neuroinflammation, particularly microglial reactivity and consequent dysregulation of hippocampal neurogenesis and oligodendrocyte lineage cells, is central to CRCI. We hypothesized that similar cellular mechanisms may contribute to the persistent neurological symptoms associated with even mild SARS-CoV-2 respiratory infection. Here, we explored neuroinflammation caused by mild respiratory SARS-CoV-2 infection - without neuroinvasion - and effects on hippocampal neurogenesis and the oligodendroglial lineage. Using a mouse model of mild respiratory SARS-CoV-2 infection induced by intranasal SARS-CoV-2 delivery, we found white matter-selective microglial reactivity, a pattern observed in CRCI. Human brain tissue from 9 individuals with COVID-19 or SARS-CoV-2 infection exhibits the same pattern of prominent white matter-selective microglial reactivity. In mice, pro-inflammatory CSF cytokines/chemokines were elevated for at least 7-weeks post-infection; among the chemokines demonstrating persistent elevation is CCL11, which is associated with impairments in neurogenesis and cognitive function. Humans experiencing long-COVID with cognitive symptoms (48 subjects) similarly demonstrate elevated CCL11 levels compared to those with long-COVID who lack cognitive symptoms (15 subjects). Impaired hippocampal neurogenesis, decreased oligodendrocytes and myelin loss in subcortical white matter were evident at 1 week, and persisted until at least 7 weeks, following mild respiratory SARS-CoV-2 infection in mice. Taken together, the findings presented here illustrate striking similarities between neuropathophysiology after cancer therapy and after SARS-CoV-2 infection, and elucidate cellular deficits that may contribute to lasting neurological symptoms following even mild SARS-CoV-2 infection.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 260: 119802, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34004425

RESUMEN

In order to realize calibration model transfer of near infrared (NIR) spectra without standards, scale invariant feature transform (SIFT) algorithm was applied to extract characteristic spectral points of NIR spectra in this study. Three sets of spectral points were selected by SIFT from the spectra of precision detection (SPD) of a radix scutellariae sample by continuously testing the sample three times. Aiming at obtaining high consistency of the three sets, the orthogonal table L9 (34) was used to optimize the parameters of SIFT. Basing on the NIR spectra of several representative radix scutellariae samples, a series of spectral point sets were screened by SIFT with the optimized parameters. Three methods of further treating the spectral points sets to optimize the combination of the spectral points and provided three spectral point sets, which were recorded as Ui, Uu and Uur, respectively. The partial least square (PLS) calibration models for predicting baicalin content of radix scutellariae were built on whole wavelengths, Ui, Uu and Uur at different number of latent variables (nLVs), respectively. Compared with other PLS models, the models of SIFTur-PLS built on Uur, which was obtained by taking union of the firstly selected spectral point sets, then eliminating the points with high deviance of SPD and those with high correlativity from the union, are most robust and always give lower or lowest prediction errors for both master and slave samples at many nLVs. It is a good way to filter stable, highly independent and characteristic spectral points to build robust PLS calibration models by combining SIFT algorithm with standard deviance analysis of SPD and correlative analysis. The models can be directly shared by the slave instrument, without needing transfer sets, and without requiring to correct the spectra of slave instruments or spectral calibration models.

15.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117647, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31655388

RESUMEN

Basing on the wavelengths with consistent and stable spectral signals between spectrometers, wavelength combinations were screened by different methods to obtain robust and simple near infrared spectra (NIR) calibration models that can be shared by slave spectrometers directly. Firstly, the wavelength set of Usc, at which the spectral signals between spectrometers are consistent and stable, was obtained by the method of screening the wavelengths with consistent and stable signals between spectrometers (SWCSS for short). Then, the wavelength set of Uscr whose spectral responses are correlated with dependent variables strongly was selected from Usc. Basing on Uscr, the methods of uninformative variable elimination (UVE), variable importance in projection (VIP) and selectivity ratio (SR) were applied to further screen optimal wavelength sets to obtain better NIR calibration models. These sets were recorded as UscrUVE, UscrVIP and UscrSR, respectively. The NIR partial least squares (PLS) models for predicting total alkaloids content of tobacco leaves were built on the three optimal wavelength sets, and named as UscrUVE-PLS, UscrVIP-PLS, UscrSR-PLS, respectively. Both UscrUVE-PLS and UscrVIP-PLS give satisfactory prediction errors for master and slave samples, and work better than the PLS model built on the whole wavelengths (WW-PLS) after piecewise direct standardization (PDS) calibration. The results show that further optimizing wavelength combinations based on consistent and stable spectral information cannot only simplify PLS models and improve the models' efficiency, but also ensure the models' accuracy when they are transferred to slave spectrometers. Wavelength selection based on the whole wavelengths without considering spectra consistency between spectrometers can improve the performance of the calibration models on the master spectrometer but cannot ensure the prediction accuracy of the slave samples.

16.
Sci Transl Med ; 11(519)2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31748226

RESUMEN

Diffuse midline gliomas (DMGs) are universally lethal malignancies occurring chiefly during childhood and involving midline structures of the central nervous system, including thalamus, pons, and spinal cord. These molecularly related cancers are characterized by high prevalence of the histone H3K27M mutation. In search of effective therapeutic options, we examined multiple DMG cultures in sequential quantitative high-throughput screens (HTS) of 2706 approved and investigational drugs. This effort generated 19,936 single-agent dose responses that inspired a series of HTS-enabled drug combination assessments encompassing 9195 drug-drug examinations. Top combinations were validated across patient-derived cell cultures representing the major DMG genotypes. In vivo testing in patient-derived xenograft models validated the combination of the multi-histone deacetylase (HDAC) inhibitor panobinostat and the proteasome inhibitor marizomib as a promising therapeutic approach. Transcriptional and metabolomic surveys revealed substantial alterations to key metabolic processes and the cellular unfolded protein response after treatment with panobinostat and marizomib. Mitigation of drug-induced cytotoxicity and basal mitochondrial respiration with exogenous application of nicotinamide mononucleotide (NMN) or exacerbation of these phenotypes when blocking nicotinamide adenine dinucleotide (NAD+) production via nicotinamide phosphoribosyltransferase (NAMPT) inhibition demonstrated that metabolic catastrophe drives the combination-induced cytotoxicity. This study provides a comprehensive single-agent and combinatorial drug screen for DMG and identifies concomitant HDAC and proteasome inhibition as a promising therapeutic strategy that underscores underrecognized metabolic vulnerabilities in DMG.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Glioma/tratamiento farmacológico , Ensayos Analíticos de Alto Rendimiento/métodos , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias del Tronco Encefálico/tratamiento farmacológico , Muerte Celular , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Glioma/genética , Glioma/metabolismo , Humanos , Lactonas/farmacología , Lactonas/uso terapéutico , Masculino , Metabolómica , Ratones , Panobinostat/farmacología , Panobinostat/uso terapéutico , Pirroles/farmacología , Pirroles/uso terapéutico , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Transcripción Genética/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Nature ; 573(7775): 539-545, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31534222

RESUMEN

High-grade gliomas are lethal brain cancers whose progression is robustly regulated by neuronal activity. Activity-regulated release of growth factors promotes glioma growth, but this alone is insufficient to explain the effect that neuronal activity exerts on glioma progression. Here we show that neuron and glioma interactions include electrochemical communication through bona fide AMPA receptor-dependent neuron-glioma synapses. Neuronal activity also evokes non-synaptic activity-dependent potassium currents that are amplified by gap junction-mediated tumour interconnections, forming an electrically coupled network. Depolarization of glioma membranes assessed by in vivo optogenetics promotes proliferation, whereas pharmacologically or genetically blocking electrochemical signalling inhibits the growth of glioma xenografts and extends mouse survival. Emphasizing the positive feedback mechanisms by which gliomas increase neuronal excitability and thus activity-regulated glioma growth, human intraoperative electrocorticography demonstrates increased cortical excitability in the glioma-infiltrated brain. Together, these findings indicate that synaptic and electrical integration into neural circuits promotes glioma progression.


Asunto(s)
Encéfalo/fisiopatología , Sinapsis Eléctricas/patología , Fenómenos Electrofisiológicos , Glioma/fisiopatología , Animales , Encéfalo/citología , Membrana Celular/patología , Proliferación Celular , Uniones Comunicantes/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Ratones , Ratones Endogámicos NOD , Neuronas/patología , Optogenética , Potasio/metabolismo , Transmisión Sináptica , Células Tumorales Cultivadas
18.
Neuron ; 103(2): 250-265.e8, 2019 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-31122677

RESUMEN

Activity-dependent myelination is thought to contribute to adaptive neurological function. However, the mechanisms by which activity regulates myelination and the extent to which myelin plasticity contributes to non-motor cognitive functions remain incompletely understood. Using a mouse model of chemotherapy-related cognitive impairment (CRCI), we recently demonstrated that methotrexate (MTX) chemotherapy induces complex glial dysfunction for which microglial activation is central. Here, we demonstrate that remote MTX exposure blocks activity-regulated myelination. MTX decreases cortical Bdnf expression, which is restored by microglial depletion. Bdnf-TrkB signaling is a required component of activity-dependent myelination. Oligodendrocyte precursor cell (OPC)-specific TrkB deletion in chemotherapy-naive mice results in impaired cognitive behavioral performance. A small-molecule TrkB agonist rescues both myelination and cognitive impairment after MTX chemotherapy. This rescue after MTX depends on intact TrkB expression in OPCs. Taken together, these findings demonstrate a molecular mechanism required for adaptive myelination that is aberrant in CRCI due to microglial activation.


Asunto(s)
Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/patología , Inmunosupresores/uso terapéutico , Metotrexato/uso terapéutico , Vaina de Mielina/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Trastornos del Conocimiento/genética , Modelos Animales de Enfermedad , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Vaina de Mielina/patología , Vaina de Mielina/ultraestructura , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Compuestos Orgánicos/uso terapéutico , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Reconocimiento en Psicología/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Urea/análogos & derivados , Urea/metabolismo
19.
J Pharm Biomed Anal ; 170: 295-304, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-30951995

RESUMEN

Near infrared spectroscopy (NIR) was applied to discriminate the roots of salvia miltiorhiza Bunge (Danshen for short) and Salvia yunnanensis C. H. Wright (Zidanshen for short) by means of principal component analysis (PCA), improved and simplified K nearest neighbors (IS-KNN). Furthermore, an ultra-high performance liquid chromatographic (UHPLC) coupled with photodiode-array detector was developed for building fingerprints of lipophilic components of Danshen and Zidanshen, respectively. Basing on NIR information, both PCA and IS-KNN method classified the two kinds of Chinese medical herbs with 100% accuracy. The chromatographic fingerprints of the lipophilic components of Danshen and Zidanshen have 10 and 12 common peaks, respectively. Liquid chromatography coupled with mass spectroscopy (LC-MS-MS) was applied to identify these peaks. Among these, three small peaks in the fingerprints of Zidanshen are not found in Danshen, one of which was identified as α-lapachone, and the other two compounds were not yet identified; a small peak after tanshinone IIA in the fingerprints of Danshen was not found in Zidanshen, which was identified as miltirone. The two herbs have 10 common lipophilic components. The similarity between the two reference chromatograms of Zidanshen and Danshen is 0.902, but the mean similaritie between Zidanshen (or Danshen) fingerprints and its own reference chromatogram is 0.973 (or 0.976). The contents of main lipophilic components are significantly lower in Zidanshen than in Danshen (P < 0.01 or P < 0.05). The results indicate that the two Chinese medical materials are not only different in NIR spectra, but also different in species and quantities of lipophilic components. NIR spectra analysis can identify Danshen and Zidanshen rapidly and accurately. UHPLC coupled with MS analysis demonstrates the detail differences between the two herbs both in species and contents of their lipophilic components.


Asunto(s)
Raíces de Plantas/química , Salvia miltiorrhiza/química , Salvia/química , Abietanos/química , Compuestos de Azabiciclo/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Ciclooctanos/química , Medicamentos Herbarios Chinos/química , Estudios de Evaluación como Asunto , Fenantrenos/química , Piperidinas/química , Análisis de Componente Principal , Espectrometría de Masas en Tándem/métodos
20.
Acta Cir Bras ; 34(1): e20190010000007, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30785508

RESUMEN

PURPOSE: To investigate the impact of Ramipril (RAM) on the expressions of insulin-like growth factor-1 (IGF-1) and renal mesangial matrix (RMM) in rats with diabetic nephropathy (DN). METHODS: The Sprague Dawley rats were divided into normal control (NC) group (n = 12), DN group (n = 11), and DN+RAM group (n = 12). The ratio of renal weight to body weight (RBT), fasting blood glucose (FBG), HbA1c, 24-h urine protein (TPU), blood urea nitrogen (BUN), creatinine (Cr), renal pathological changes, the levels of IGF-1, fibronectin (FN), type IV collagen (Col-IV), and matrix metalloproteinases (MMP)-2 were compared among the groups. RESULTS: Compared with NC group, the RBT, FBG, HbA1c, TPU, BUN, Cr, and RMM in DN group were significantly increased (P < 0.05), the IGF-1, FN, and Col-IV were significantly upregulated (P < 0.05), while MMP was significantly downregulated (P < 0.05). Compared with DN group, the indexes except for the FBG and HbA1c in DN+RAM group were significantly improved (P < 0.05), among which IGF-1 exhibited significant positive correlation with TPU(r=0.937), FN(r=0.896) and Col-IV(r=0.871), while significant negative correlation with MMP-2 (r=-0.826) (P<0.05). CONCLUSION: RAM may protect the kidneys by suppressing IGF-1 and mitigating the accumulation of RMM.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Nefropatías Diabéticas/tratamiento farmacológico , Factor I del Crecimiento Similar a la Insulina/antagonistas & inhibidores , Células Mesangiales/efectos de los fármacos , Ramipril/farmacología , Animales , Colágeno Tipo IV/efectos de los fármacos , Colágeno Tipo IV/metabolismo , Nefropatías Diabéticas/metabolismo , Fibronectinas/efectos de los fármacos , Fibronectinas/metabolismo , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Metaloproteinasas de la Matriz/efectos de los fármacos , Metaloproteinasas de la Matriz/metabolismo , Células Mesangiales/metabolismo , Ratas , Ratas Sprague-Dawley
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