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1.
Cell ; 186(26): 5739-5750.e17, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38070510

RESUMO

Conscious perception is greatly diminished during sleep, but the underlying circuit mechanism is poorly understood. We show that cortical ignition-a brain process shown to be associated with conscious awareness in humans and non-human primates-is strongly suppressed during non-rapid-eye-movement (NREM) sleep in mice due to reduced cholinergic modulation and rapid inhibition of cortical responses. Brain-wide functional ultrasound imaging and cell-type-specific calcium imaging combined with optogenetics showed that activity propagation from visual to frontal cortex is markedly reduced during NREM sleep due to strong inhibition of frontal pyramidal neurons. Chemogenetic activation and inactivation of basal forebrain cholinergic neurons powerfully increased and decreased visual-to-frontal activity propagation, respectively. Furthermore, although multiple subtypes of dendrite-targeting GABAergic interneurons in the frontal cortex are more active during wakefulness, soma-targeting parvalbumin-expressing interneurons are more active during sleep. Chemogenetic manipulation of parvalbumin interneurons showed that sleep/wake-dependent cortical ignition is strongly modulated by perisomatic inhibition of pyramidal neurons.


Assuntos
Eletroencefalografia , Parvalbuminas , Sono , Animais , Camundongos , Neurônios Colinérgicos/fisiologia , Lobo Frontal/metabolismo , Parvalbuminas/metabolismo , Sono/fisiologia , Vigília/fisiologia
2.
Diabetes Obes Metab ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171569

RESUMO

AIM: We aimed to investigate the long-term impact of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on thyroid function, cardiovascular health, renal outcomes and adverse events in individuals with obesity and without type 2 diabetes (T2D). MATERIALS AND METHODS: In this observational cohort study, we used propensity score matching to construct comparable cohorts of individuals with obesity and without T2D who were new to GLP-1 RA treatment and those who did not receive glucose-lowering medications. In total, 3,729,925 individuals with obesity were selected from the TriNetX Global Network, with an index event between 1 January 2016 and 31 March 2024. The primary outcomes were safety, cardiovascular, thyroid and clinical biochemical profile outcomes occurring within 5 years following the index event. RESULTS: After propensity score matching, the study included 12,123 individuals in each group. GLP-1 RA treatment was associated with a significantly lower risk of all-cause mortality (hazard ratio 0.23; 95% confidence interval 0.15-0.34) and several cardiovascular complications, including ischaemic heart disease, heart failure, arrhythmias, hypertension, stroke and atrial fibrillation (all p < 0.05). GLP-1 RAs were also associated with a lower risk of acute kidney injury and allergic reactions. These protective effects were consistent across various subgroups and regions. CONCLUSIONS: In this large observational study, GLP-1 RAs showed long-term protective effects on cardiovascular health, renal outcomes and adverse events in individuals with obesity and without T2D. Our findings suggest that GLP-1 RAs may offer a comprehensive approach to managing obesity and its related comorbidities, potentially improving overall health and survival in this population.

3.
Cereb Cortex ; 33(3): 622-633, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35253853

RESUMO

The social brain hypothesis posits that a disproportionate encephalization in primates enabled to adapt behavior to a social context. Also, it has been proposed that phylogenetically recent brain areas are disproportionally affected by neurodegeneration. Using structural and functional magnetic resonance imaging, the present study investigates brain-behavior associations and neural integrity of hyperspecialized and domain-general cortical social brain areas in behavioral variant frontotemporal dementia (bvFTD). The results revealed that both structure and function of hyperspecialized social areas in the middle portion of the superior temporal sulcus (STS) are compromised in bvFTD, while no deterioration was observed in domain general social areas in the posterior STS. While the structural findings adhered to an anterior-posterior gradient, the functional group differences only occurred in the hyperspecialized locations. Activity in specialized regions was associated with structural integrity of the amygdala and with social deficits in bvFTD. In conclusion, the results are in line with the paleo-neurology hypothesis positing that neurodegeneration primarily hits cortical areas showing increased specialization, but also with the compatible alternative explanation that anterior STS regions degenerate earlier, based on stronger connections to and trans-neuronal spreading from regions affected early in bvFTD.


Assuntos
Demência Frontotemporal , Humanos , Demência Frontotemporal/patologia , Encéfalo , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico , Testes Neuropsicológicos
4.
Diabetes Obes Metab ; 25(10): 2928-2936, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37455666

RESUMO

AIMS: To analyse the genome-wide association study (GWAS) data of patients with type 1 diabetes mellitus (T1D) in order to develop a risk score for the genetic effects on T1D risk and age at diagnosis in the Taiwanese population. MATERIALS AND METHODS: We selected 610 patients with T1D and 2511 healthy individuals from an electronic medical record database of more than 300 000 individuals with genetic information, analysed their GWAS data, and developed a polygenic risk score (PRS). RESULTS: The PRS, based on 149 selected single-nucleotide polymorphisms, could effectively predict T1D risk. A PRS increase was associated with increased T1D risk (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.72-2.55). Moreover, a 1-unit increase in standardized T1D PRS decreased the age at diagnosis by 0.74 years. Combined PRS and human leukocyte antigen (HLA) DQA1*03:02-DQA1*05:01 genotypes could accurately predict T1D risk. In multivariable models, HLA variants and PRS were independent risk factors for T1D risk (OR 3.76 [95% CI 1.54-9.16] and 1.71 [95% CI 1.37-2.13] for HLA DQA1*03:02-DQA1*05:01 and PRS, respectively). In a limited study population of those aged ≤18 years, PRS remained significantly associated with T1D risk. The association between T1D PRS and age at diagnosis was more obvious among males and patients aged ≤18 years. CONCLUSIONS: Polygenic risk score and HLA variations enable personalized risk estimates, enhance newborn screening efficiency for ketoacidosis prevention, and addresses the gap in data on T1D prediction in isolated Asian populations.


Assuntos
Diabetes Mellitus Tipo 1 , Masculino , Recém-Nascido , Humanos , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Fatores de Risco , Medição de Risco
5.
Int J Mol Sci ; 22(4)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572095

RESUMO

Long non-coding RNA steroid receptor RNA activators (LncRNA SRAs) are implicated in the ß-cell destruction of Type 1 diabetes mellitus (T1D), but functional association remains poorly understood. Here, we aimed to verify the role of LncRNA SRA regulation in ß-cells. LncRNA SRAs were highly expressed in plasma samples and peripheral blood mononuclear cells (PBMCs) from T1D patients. LncRNA SRA was strongly upregulated by high-glucose treatment. LncRNA SRA acts as a microRNA (miR)-146b sponge through direct sequence-structure interactions. Silencing of lncRNA SRA increased the functional genes of Tregs, resulting in metabolic reprogramming, such as decreased lactate levels, repressed lactate dehydrogenase A (LDHA)/phosphorylated LDHA (pLDHA at Tyr10) expression, decreased reactive oxygen species (ROS) production, increased ATP production, and finally, decreased ß-cell apoptosis in vitro. There was a positive association between lactate level and hemoglobin A1c (HbA1c) level in the plasma from patients with T1D. Recombinant human interleukin (IL)-2 treatment repressed lncRNA SRA expression and activity in ß-cells. Higher levels of lncRNA-SRA/lactate in the plasma are associated with poor regulation in T1D patients. LncRNA SRA contributed to T1D pathogenesis through the inhibition of miR-146b in ß-cells, with activating signaling transduction of interleukin-1 receptor-associated kinase 1 (IRAK1)/LDHA/pLDHA. Taken together, LncRNA SRA plays a critical role in the function of ß-cells.


Assuntos
Proteínas de Transporte/genética , Diabetes Mellitus Tipo 1/patologia , Células Secretoras de Insulina/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Adolescente , Antagomirs/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Retroalimentação Fisiológica/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Hemoglobinas Glicadas/análise , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Quinases Associadas a Receptores de Interleucina-1/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Masculino , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , RNA Longo não Codificante/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
6.
Eur J Neurosci ; 52(5): 3470-3484, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32618060

RESUMO

The human amygdala is considered a key region for successful emotion recognition. We recently reported that temporal lobe surgery (TLS), including resection of the amygdala, does not affect emotion recognition performance (Journal of Neuroscience, 2018, 38, 9263). In the present study, we investigate the neural basis of this preserved function at the network level. We use generalized psychophysiological interaction and graph theory indices to investigate network level characteristics of the emotion recognition network in TLS patients and healthy controls. Based on conflicting emotion processing theories, we anticipated two possible outcomes: a substantial increase of the non-amygdalar connections of the emotion recognition network to compensate functionally for the loss of the amygdala, in line with basic emotion theory versus only minor changes in network level properties as predicted by psychological construction theory. We defined the emotion recognition network in the total sample and investigated group differences on five network level indices (i.e. characteristic path length, global efficiency, clustering coefficient, local efficiency and small-worldness). The results did not reveal a significant increase in the left or right temporal lobectomy group (compared to the control group) in any of the graph measures, indicating that preserved behavioural emotion recognition in TLS is not associated with a massive connectivity increase between non-amygdalar nodes at network level. We conclude that the emotion recognition network is robust and functionally able to compensate for structural damage without substantial global reorganization, in line with a psychological construction theory.


Assuntos
Mapeamento Encefálico , Epilepsia do Lobo Temporal , Tonsila do Cerebelo/cirurgia , Emoções , Humanos , Imageamento por Ressonância Magnética , Lobo Temporal/cirurgia
7.
Molecules ; 25(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31940978

RESUMO

Two effective molecularly imprinted polymers for the adsorption of alpha-lipoic acid (ALA) were synthesized by the cross-linking of chitosan with epichlorohydrin (ECH) and glutaraldehyde (GLU), respectively, in the presence of ALA as template molecules. Investigations on the molar ratios of ALA and chitosan (-NH2) in the preparation of chitosan molecularly imprinted polymers (MIPs) were carried out with a factor of ALA rebinding capabilities. The surface morphology and chemical properties of the polymers were characterized. The optimized MIPs crosslinked by ECH (MIPs-ECH) and MIPs crosslinked by GLU (MIPs-GLU) had adsorption capabilities of 12.09 mg/g and 19.72 mg/g for ALA, respectively. The adsorption behaviors of two kinds of chitosan MIPs including adsorption kinetics and isotherms were investigated in detail. Adsorption and kinetic binding experiments showed that the prepared MIPs-ECH and MIPs-GLU had selective adsorption and excellent affinity for ALA. In addition, the possible binding models between ALA and chitosan oligosaccharide were predicted by molecular dynamics simulation.


Assuntos
Quitosana/química , Impressão Molecular , Ácido Tióctico/química , Adsorção
8.
J Neurosci ; 38(43): 9263-9274, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30228228

RESUMO

Humans with amygdalar lesions show proportional reductions of the emotional response to facial expressions in the fusiform face area as well as deficits in emotion recognition from facial expressions. While processing of bodily expressions shares many similarities with facial expressions, there is no substantial evidence that lesions of the amygdala result in similar behavioral and neural sequelae. We combined behavioral assessment with functional neuroimaging in a group of male and female humans with unilateral anterior temporal lobe (ATL) resections, including the amygdala (right: n = 10; left: n = 10) and 12 matched controls. The objective was to assess whether the amygdala is crucial for the recognition of body expressions and for modulatory effects on distant areas during perception of body expressions. The behavioral results revealed normal performance in both patient groups on emotion categorization of body expressions. The neuroimaging results showed that ATL patients displayed no enhanced activations in right fusiform body area and left extrastriate body area and that left ATL patients additionally displayed no enhanced activations in right posterior superior temporal sulcus and right extrastriate body area, respectively. Multivoxel pattern analysis revealed altered categorization capacity between emotional and neutral stimuli in right posterior superior temporal sulcus in right ATL patients. In addition, we also found emotional enhancement in frontal, parietal, occipital, and cingulate regions in controls. Together, our data show that the amygdala and ATLs are not necessary for recognition of dynamic body expressions, but suggest that amygdala lesions affect body emotion processing in distant brain areas.SIGNIFICANCE STATEMENT For humans, information from emotional expressions of others is crucial to support social interactions. The majority of emotion studies has focused on facial expressions; however, in daily life, we also use information from body postures and body movement. Visual processing of body expressions relies on a brain network, including body-specific visual areas and visuomotor areas. Even though the importance of the amygdala and its modulatory effects on distant brain regions have been documented, it remains unclear whether the amygdala plays a crucial role in emotional body processing. By combining behavioral and neuroimaging data in patients with amygdalar lesions, we provide further evidence for its modulatory effect on distant areas during the perception of body expressions.


Assuntos
Lobectomia Temporal Anterior/tendências , Emoções/fisiologia , Cinésica , Estimulação Luminosa/métodos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/psicologia , Epilepsia Resistente a Medicamentos/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/cirurgia
9.
Environ Toxicol ; 34(2): 179-187, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30387921

RESUMO

LncRNA transcripts have been emerged as gene regulators through transcriptional and posttranscriptional regulation. Monosodium urate monohydrate (MSU) elicits inflammatory response and a critical regulator of bone erosion in gout. The aim of this study is to clarify the pro-osteogenic role of LncRNA in MSU-induced osteoclast differentiation. We performed microarray analysis to identify stage specific expressions of LncRNA and mRNA during osteoclast differentiation in RAW264.7 cells. Among the 314 pairs of LncRNA-mRNA coexpressed patterns in the osteoclast lineage, 22 pairs revealed to have inflammatory function. Importantly, LncRNA-Jak3 and Jak3 co-expression patterns were significantly upregulated in the osteoclasts. In specific, Jak3 contributes to MSU-induced osteoclasts differentiation by positively regulating expression of the osteoclast factor, nuclear factor of activated T-cells 1 (Nfatc1). Mechanistically, LncRNA-Jak3-mediated Nfatc1 activation upregulated cathepsin K (Ctsk) expressions. LncRNA-Jak3 knockdown abolished formation of MSU-induced mature osteoclasts. In addition, we found that gout patients showed increased levels of LncRNA-Jak3 in the mononuclear cells. Our data demonstrate that the critical functional role of LncRNA-Jak3 in osteoclast differentiation via Jak3/Nfatc1/Ctsk axis. Finally, characterization of these regulatory networks is likely to reveal novel drug targets and opportunities for therapeutic intervention in bone erosion.


Assuntos
Catepsina K/genética , Diferenciação Celular/efeitos dos fármacos , Janus Quinase 3/genética , Fatores de Transcrição NFATC/genética , Osteoclastos/efeitos dos fármacos , RNA Longo não Codificante/genética , Ácido Úrico/toxicidade , Animais , Diferenciação Celular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Gota/metabolismo , Células HEK293 , Humanos , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Células RAW 264.7 , Ácido Úrico/metabolismo
10.
Neuroimage ; 172: 250-262, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29339312

RESUMO

Psychological construction models of emotion state that emotions are variable concepts constructed by fundamental psychological processes, whereas according to basic emotion theory, emotions cannot be divided into more fundamental units and each basic emotion is represented by a unique and innate neural circuitry. In a previous study, we found evidence for the psychological construction account by showing that several brain regions were commonly activated when perceiving different emotions (i.e. a general emotion network). Moreover, this set of brain regions included areas associated with core affect, conceptualization and executive control, as predicted by psychological construction models. Here we investigate directed functional brain connectivity in the same dataset to address two questions: 1) is there a common pathway within the general emotion network for the perception of different emotions and 2) if so, does this common pathway contain information to distinguish between different emotions? We used generalized psychophysiological interactions and information flow indices to examine the connectivity within the general emotion network. The results revealed a general emotion pathway that connects neural nodes involved in core affect, conceptualization, language and executive control. Perception of different emotions could not be accurately classified based on the connectivity patterns from the nodes of the general emotion pathway. Successful classification was achieved when connections outside the general emotion pathway were included. We propose that the general emotion pathway functions as a common pathway within the general emotion network and is involved in shared basic psychological processes across emotions. However, additional connections within the general emotion network are required to classify different emotions, consistent with a constructionist account.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Rede Nervosa/fisiologia , Adulto , Mapeamento Encefálico/métodos , Imagem Ecoplanar/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Modelos Teóricos , Psicofisiologia , Adulto Jovem
11.
Regul Toxicol Pharmacol ; 97: 152-162, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29909271

RESUMO

The presence of pesticide residues in fruit has been of extensive concern worldwide. In this paper, pesticide residues in peach samples in China and their dietary exposure risks for the Chinese general population and children were evaluated. Thirty-nine different pesticides were detected, and 92.3% of samples contained one or more pesticide residues. The most frequently detected pesticide was carbendazim with a detection rate of 60.6%. Residues for eight pesticides in 3.2% of the samples exceeded their MRLs with the highest exceedance of 345%. The results demonstrated that the chronic dietary risks were extremely low for both the general population and children in China. Acute risks from carbendazim, chlorpyrifos, cyhalothrin, cypermethrin, pyridaben and triazophos exposures for children and triazophos for the general population exceeded the acceptable level in the worst case scenario. Only %ARfD of triazophos exceeded 100 when intakes were calculated at the 97.5th percentile of residue level distribution. The risk scoring scheme showed nine pesticides that were considered to pose a higher risk. Different use suggestions for the 39 detected pesticides were proposed to protect the health of consumers. More strictly controlled management of banned pesticides and those suggested for gradually diminished use until banned is highly recommended.


Assuntos
Dieta , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , China , Dieta/efeitos adversos , Frutas/química , Humanos , Resíduos de Praguicidas/efeitos adversos , Medição de Risco , Inquéritos e Questionários
12.
Magn Reson Med ; 77(2): 592-602, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26834053

RESUMO

PURPOSE: To test whether susceptibility imaging can detect microvenous oxygen saturation changes, induced by hyperoxia, in the rat brain. METHODS: A three-dimensional gradient-echo with a flow compensation sequence was used to acquire T2*-weighted images of rat brains during hyperoxia and normoxia. Quantitative susceptibility mapping (QSM) and QSM-based microvenous oxygenation venography were computed from gradient-echo (GRE) phase images and compared between the two conditions. Pulse oxygen saturation (SpO2 ) in the cortex was examined and compared with venous oxygen saturation (SvO2 ) estimated by QSM. Oxygen saturation change calculated by a conventional Δ R2* map was also compared with the ΔSvO2 estimated by QSM. RESULTS: Susceptibilities of five venous and tissue regions were quantified separately by QSM. Venous susceptibility was reduced by nearly 10%, with an SvO2 shift of 10% during hyperoxia. A hyperoxic effect, confirmed by SpO2 measurement, resulted in an SvO2 increase in the cortex. The ΔSvO2 between hyperoxia and normoxia was consistent with what was estimated by the Δ R2* map in five regions. CONCLUSION: These findings suggest that a quantitative susceptibility map is a promising technique for SvO2 measurement. This method may be useful for quantitatively investigating oxygenation-dependent functional MRI studies. Magn Reson Med 77:592-602, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Assuntos
Encéfalo/metabolismo , Veias Cerebrais/metabolismo , Hiperóxia/metabolismo , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Oximetria/métodos , Oxigênio/metabolismo , Algoritmos , Animais , Encéfalo/diagnóstico por imagem , Hiperóxia/diagnóstico por imagem , Aumento da Imagem/métodos , Masculino , Imagem Molecular/métodos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Hum Brain Mapp ; 36(10): 4184-201, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26219630

RESUMO

Whether neuroimaging findings support discriminable neural correlates of emotion categories is a longstanding controversy. Two recent meta-analyses arrived at opposite conclusions, with one supporting (Vytal and Hamann []: J Cogn Neurosci 22:2864-2885) and the other opposing this proposition (Lindquist et al. []: Behav Brain Sci 35:121-143). To obtain direct evidence regarding this issue, we compared activations for four emotions within a single fMRI design. Angry, happy, fearful, sad and neutral stimuli were presented as dynamic body expressions. In addition, observers categorized motion morphs between neutral and emotional stimuli in a behavioral experiment to determine their relative sensitivities. Brain-behavior correlations revealed a large brain network that was identical for all four tested emotions. This network consisted predominantly of regions located within the default mode network and the salience network. Despite showing brain-behavior correlations for all emotions, muli-voxel pattern analyses indicated that several nodes of this emotion general network contained information capable of discriminating between individual emotions. However, significant discrimination was not limited to the emotional network, but was also observed in several regions within the action observation network. Taken together, our results favor the position that one common emotional brain network supports the visual processing and discrimination of emotional stimuli.


Assuntos
Emoções , Percepção Social , Adulto , Expressão Facial , Feminino , Humanos , Individualidade , Cinésica , Imageamento por Ressonância Magnética , Masculino , Movimento (Física) , Rede Nervosa/fisiologia , Observação , Máquina de Vetores de Suporte , Adulto Jovem
14.
Int J Mol Sci ; 16(8): 18328-47, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26262607

RESUMO

Chitosan is widely used in molecular imprinting technology (MIT) as a functional monomer or supporting matrix because of its low cost and high contents of amino and hydroxyl functional groups. The various excellent properties of chitosan, which include nontoxicity, biodegradability, biocompatibility, and attractive physical and mechanical performances, make chitosan a promising alternative to conventional functional monomers. Recently, chitosan molecularly-imprinted polymers have gained considerable attention and showed significant potential in many fields, such as curbing environmental pollution, medicine, protein separation and identification, and chiral-compound separation. These extensive applications are due to the polymers' desired selectivity, physical robustness, and thermal stability, as well as their low cost and easy preparation. Cross-linkers, which fix the functional groups of chitosan around imprinted molecules, play an important role in chitosan molecularly-imprinted polymers. This review summarizes the important cross-linkers of chitosan molecularly-imprinted polymers and illustrates the cross-linking mechanism of chitosan and cross-linkers based on the two glucosamine units. Finally, some significant attempts to further develop the application of chitosan in MIT are proposed.


Assuntos
Quitosana/química , Reagentes de Ligações Cruzadas/química , Impressão Molecular/métodos , Polímeros/química
15.
J Magn Reson Imaging ; 39(5): 1118-25, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24027126

RESUMO

PURPOSE: To investigate what extent brain regions are continuously interacting during resting-state, independent component analyses (ICA) was applied to analyze resting-state functional MRI (RS-fMRI) data. According to the analyzed results, it was surprisingly found that low frequency fluctuations (LFFs), which belong to the 1/f signal (a signal with power spectrum whose power spectral density is inversely proportional to the frequency), have been classified into groups using ICA; furthermore, the spatial distributions of these groups within the brain were found to resemble the spatial distributions of different networks, which manifests that the signal characteristics of RS LFFs are distinct across networks. In our work, we applied the 1/f model in the fractal analyses to further investigate this distinction. MATERIALS AND METHODS: Twenty healthy participants got involved in this study. They were scanned to acquire the RS-fMRI data. The acquired data were first processed with ICA to obtain the networks of the resting brain. Afterward, the blood-oxygenation level dependent (BOLD) signals of these networks were processed with the fractal analyses for obtaining the fractal parameter α. RESULTS: α was found to significantly vary across networks, which reveals that the fractal characteristic of LFFs differs across networks. According to prior literatures, this difference could be brought by the discrepancy of hemodynamic response amplitude (HRA) between networks. Hence, in our work, we also performed the computational simulation to discover the relationship between α and HRA. Based on the simulation results, HRA is highly linear-correlated with the fractal characteristics of LFFs which is revealed by α. CONCLUSION: Our results support that the origin of RS-fMRI signals contains arterial fluctuations. Hence, in addition to the commonly used method such as synchrony analysis and power spectral analysis, another approach, the fractal analysis, is suggested for acquiring the information of hemodynamic responses by means of RS-fMRI data.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Fractais , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Descanso/fisiologia , Sensibilidade e Especificidade , Adulto Jovem
16.
Food Chem X ; 22: 101498, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38911915

RESUMO

A thermally stable co-delivery system for lactoferrin (LF) and iron(II) was developed to address iron deficiency anemia. Complexes were formed between LF, succinylated sodium caseinate (S.NaCas) and FeSO4 with high yield (∼85%). LF-S.NaCas-Fe complexes achieved loading capacities for iron(II) between 2.5 and 12 mg g-1and LF loading capacities between 250 and 690 mg g-1, depending upon initial Fe2+ concentrations and LF ratios. The LF-S.NaCas complex mixtures appeared as smooth cubic particles in SEM, and gradually aggregated to amorphous particles as th iron(II) concentration increased due to iron-facilitated cross-linking. The complexation significantly improved LF thermal stability and addressed the poor solubility of iron(II) under neutral pH. After thermal treatment (95 °C, 5 min), the rehydrated complexes retained 68%-90% LF, with <10% iron(II) release. Circular dichroism spectra showed the secondary structure of the complexed LF was well retained during thermal treatment. This thermally stable system showed great potential in LF thermal protection and iron(II) fortification.

17.
In Vivo ; 38(1): 437-444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38148059

RESUMO

BACKGROUND/AIM: Acid sphingomyelinase deficiency (ASMD) is a rare lysosomal storage disorder characterized by sphingomyelin accumulation causing progressive lung disease, respiratory failure, and death. PATIENTS AND METHODS: This retrospective observational study used the TriNetX database of electronic health records for 15,108 patients with ASMD from 2000-2020. After exclusions, 8,980 individuals were followed for 10 or 20 years. Outcomes included incidence and prevalence of respiratory disorders. Associations of age, sex and race were assessed. RESULTS: Nearly all respiratory outcomes increased significantly over 20 versus 10 years. Other respiratory disorders, specified respiratory disorders and secondary pulmonary hypertension exhibited the greatest increases, reflecting progressive lung damage in ASMD. While outcomes were poor overall, older age, male sex, and racial minority status associated with greater risks, indicating differences in disease progression or care. CONCLUSION: This study confirms the progressive nature of ASMD and need for close monitoring and treatment of pulmonary complications to reduce long-term morbidity and mortality. Genetic testing enabling diagnosis even for milder, adult-onset forms is critical to optimize outcomes.


Assuntos
Doença de Niemann-Pick Tipo A , Doenças de Niemann-Pick , Adulto , Humanos , Masculino , Seguimentos , Esfingomielina Fosfodiesterase/genética , Doença de Niemann-Pick Tipo A/diagnóstico , Doença de Niemann-Pick Tipo A/genética , Pulmão
18.
Orphanet J Rare Dis ; 19(1): 144, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575988

RESUMO

BACKGROUND: Osteoporosis and its primary complication, fragility fractures, contribute to substantial global morbidity and mortality. Gaucher disease (GD) is caused by glucocerebrosidase (GBA1) deficiency, leading to skeletal complications. This study aimed to investigate the impact of the GBA1 gene on osteoporosis progression in GD patients and the specific populations. METHODS: We selected 8115 patients with osteoporosis (T-score ≤ - 2.5) and 55,942 healthy individuals (T-score > - 1) from a clinical database (N = 95,223). Monocytes from GD patients were evaluated in relation to endoplasmic reticulum (ER) stress, inflammasome activation, and osteoclastogenesis. An in vitro model of GD patient's cells treated with adeno-associated virus 9 (AAV9)-GBA1 to assess GBA1 enzyme activity, chitotriosidase activity, ER stress, and osteoclast differentiation. Longitudinal dual-energy X-ray absorptiometry (DXA) data tracking bone density in patients with Gaucher disease (GD) undergoing enzyme replacement therapy (ERT) over an extended period. RESULTS: The GBA1 gene variant rs11264345 was significantly associated [P < 0.002, Odds Ratio (OR) = 1.06] with an increased risk of bone disease. Upregulation of Calnexin, NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and Apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) was positively associated with osteoclastogenesis in patients with GD. In vitro AAV9-GBA1 treatment of GD patient cells led to enhanced GBA1 enzyme activity, reduced chitotriosidase activity, diminished ER stress, and decreased osteoclast differentiation. Long-term bone density data suggests that initiating ERT earlier in GD leads to greater improvements in bone density. CONCLUSIONS: Elevated ER stress and inflammasome activation are indicative of osteoporosis development, suggesting the need for clinical monitoring of patients with GD. Furthermore, disease-associated variant in the GBA1 gene may constitute a risk factor predisposing specific populations to osteoporosis.


Assuntos
Doença de Gaucher , Osteoporose , Humanos , Densidade Óssea/genética , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/uso terapêutico , Inflamassomos , Osteoporose/genética , Osteoporose/tratamento farmacológico
19.
J Control Release ; 373: 385-398, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38972640

RESUMO

Lipid nanoparticle-mediated co-delivery of siRNA and small molecule holds a great potential to treat metabolic dysfunction-associated steatotic liver disease (MASLD). However, targeted delivery of therapeutics to hepatocytes remains challenging. Taking the advantage of rising low density lipoprotein receptor/very-low density lipoprotein receptor (LDLR/VLDR) levels in MASLD, the biological fate of dinonylamine-ethylene glycol chlorophosphate-1-nonanol (DNNA-COP-NA) based lipid nanoparticles (LNPs) was oriented to liver tissues via apolipoprotein E (ApoE)-LDLR/VLDLR pathway. We then adopted a three-round screening strategy to optimize the formulation with both high potency and selectivity to deliver siRNA-HIF-1α (siHIF1α) and silibinin (SLB) payloads to hepatocytes. The optimized SLB/siHIF1α-LNPs mediates great siRNA delivery and transfection of hepatocytes. In high fat diet (HFD)- and carbon tetrachloride (CCl4)-induced mouse models of MASLD, SLB/siHIF1α-LNPs enabled the silencing of hypoxia inducible factor-1α (HIF-1α), a therapeutic target primarily expressed by hepatocytes, leading to significantly reduced inflammation and liver fibrosis synergized with SLB. Moreover, it is demonstrated the hepatocyte-targeting delivery of SLB/siHIF1α-LNPs has the potential to restore the immune homeostasis by modulating the population of Tregs and cytotoxic T cells in spleen. This proof-of-concept study enable siRNA and small molecule co-delivery to hepatocytes through intrinsic variation of targeting receptors for MASLD therapy.


Assuntos
Hepatócitos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Camundongos Endogâmicos C57BL , Nanopartículas , RNA Interferente Pequeno , Silibina , Animais , Silibina/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Hepatócitos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Humanos , Dieta Hiperlipídica/efeitos adversos , Lipídeos/química , Tetracloreto de Carbono , Camundongos , Fígado Gorduroso , Fígado/metabolismo
20.
Nat Commun ; 15(1): 42, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168091

RESUMO

To curb viral epidemics and pandemics, antiviral drugs are needed with activity against entire genera or families of viruses. Here, we develop a cell-based multiplex antiviral assay for high-throughput screening against multiple viruses at once, as demonstrated by using three distantly related orthoflaviviruses: dengue, Japanese encephalitis and yellow fever virus. Each virus is tagged with a distinct fluorescent protein, enabling individual monitoring in cell culture through high-content imaging. Specific antisera and small-molecule inhibitors are employed to validate that multiplexing approach yields comparable inhibition profiles to single-virus infection assays. To facilitate downstream analysis, a kernel is developed to deconvolute and reduce the multidimensional quantitative data to three cartesian coordinates. The methodology is applicable to viruses from different families as exemplified by co-infections with chikungunya, parainfluenza and Bunyamwera viruses. The multiplex approach is expected to facilitate the discovery of broader-spectrum antivirals, as shown in a pilot screen of approximately 1200 drug-like small-molecules.


Assuntos
Viroses , Vírus , Humanos , Antivirais/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Técnicas de Cultura de Células , Replicação Viral
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