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1.
NPJ Parkinsons Dis ; 10(1): 84, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615089

RESUMO

Sex differences permeate many aspects of dementia with Lewy bodies (DLB), yet sex differences in patterns of neurodegeneration in DLB remain largely unexplored. Here, we test whether grey matter networks differ between sexes in DLB and compare these findings to sex differences in healthy controls. In this cross-sectional study, we analysed clinical and neuroimaging data of patients with DLB and cognitively healthy controls matched for age and sex. Grey matter networks were constructed by pairwise correlations between 58 regional volumes after correction for age, intracranial volume, and centre. Network properties were compared between sexes and diagnostic groups. Additional analyses were conducted on w-scored data to identify DLB-specific sex differences. Data from 119 (68.7 ± 8.4 years) men and 45 women (69.9 ± 9.1 years) with DLB, and 164 healthy controls were included in this study. Networks of men had a lower nodal strength compared to women. In comparison to healthy women, the grey matter networks of healthy men showed a higher global efficiency, modularity, and fewer modules. None of the network measures showed significant sex differences in DLB. Comparing DLB patients with healthy controls revealed global differences in women and more local differences in men. Modular analyses showed a more distinct demarcation between cortical and subcortical regions in men compared with women. While topologies of grey matter networks differed between sexes in healthy controls, those sex differences were diluted in DLB patients. These findings suggest a disease-driven convergence of neurodegenerative patterns in women and men with DLB, which may inform precision medicine in DLB.

2.
Alzheimers Dement ; 20(3): 1815-1826, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38131463

RESUMO

INTRODUCTION: Sex influences neurodegeneration, but it has been poorly investigated in dementia with Lewy bodies (DLB). We investigated sex differences in brain atrophy in DLB using magnetic resonance imaging (MRI). METHODS: We included 436 patients from the European-DLB consortium and the Mayo Clinic. Sex differences and sex-by-age interactions were assessed through visual atrophy rating scales (n = 327; 73 ± 8 years, 62% males) and automated estimations of regional gray matter volume and cortical thickness (n = 165; 69 ± 9 years, 72% males). RESULTS: We found a higher likelihood of frontal atrophy and smaller volumes in six cortical regions in males and thinner olfactory cortices in females. There were significant sex-by-age interactions in volume (six regions) and cortical thickness (seven regions) across the entire cortex. DISCUSSION: We demonstrate that males have more widespread cortical atrophy at younger ages, but differences tend to disappear with increasing age, with males and females converging around the age of 75. HIGHLIGHTS: Male DLB patients had higher odds for frontal atrophy on radiological visual rating scales. Male DLB patients displayed a widespread pattern of cortical gray matter alterations on automated methods. Sex differences in gray matter measures in DLB tended to disappear with increasing age.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Humanos , Masculino , Feminino , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/patologia , Doença de Alzheimer/patologia , Caracteres Sexuais , Córtex Cerebral/patologia , Atrofia/patologia , Imageamento por Ressonância Magnética
3.
Res Sq ; 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36778448

RESUMO

Objectives: Sex differences permeate many aspects of dementia with Lewy bodies (DLB), including epidemiology, pathogenesis, disease progression, and symptom manifestation. However, less is known about potential sex differences in patterns of neurodegeneration in DLB. Here, we test whether grey matter networks also differ between female and male DLB patients. To assess the specificity of these sex differences to DLB, we additionally investigate sex differences in healthy controls (HCs). Methods: A total of 119 (68.7 ± 8.4 years) male and 45 female (69.9 ± 9.1 years) DLB patients from three European centres and the Mayo Clinic were included in this study. Additionally, we included 119 male and 45 female age-matched HCs from the Mayo Clinic. Grey matter volumes of 58 cortical, subcortical, cerebellar, and pontine brain regions derived from structural magnetic resonance images were corrected for age, intracranial volume, and centre. Sex-specific grey matter networks for DLB patients and HCs were constructed by correlating each pair of brain regions. Network properties of the correlation matrices were compared between sexes and groups. Additional analyses were conducted on W-scored data to identify DLB-specific findings. Results: Networks of male HCs and male DLB patients were characterised by a lower nodal strength compared to their respective female counterparts. In comparison to female HCs, the grey matter networks of male HCs showed a higher global efficiency, modularity, and a lower number of modules. None of the global and nodal network measures showed significant sex differences in DLB. Conclusions: The disappearance of sex differences in the structural grey matter networks of DLB patients compared to HCs may indicate a sex-dependent network vulnerability to the alpha-synuclein pathology in DLB. Future studies might investigate whether the differences in structural network measures are associated with differences in cognitive scores and clinical symptoms between the sexes.

4.
EMBO Mol Med ; 15(3): e14837, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36789546

RESUMO

Multiple sulfatase deficiency (MSD, MIM #272200) results from pathogenic variants in the SUMF1 gene that impair proper function of the formylglycine-generating enzyme (FGE). FGE is essential for the posttranslational activation of cellular sulfatases. MSD patients display reduced or absent sulfatase activities and, as a result, clinical signs of single sulfatase disorders in a unique combination. Up to date therapeutic options for MSD are limited and mostly palliative. We performed a screen of FDA-approved drugs using immortalized MSD patient fibroblasts. Recovery of arylsulfatase A activity served as the primary readout. Subsequent analysis confirmed that treatment of primary MSD fibroblasts with tazarotene and bexarotene, two retinoids, led to a correction of MSD pathophysiology. Upon treatment, sulfatase activities increased in a dose- and time-dependent manner, reduced glycosaminoglycan content decreased and lysosomal position and size normalized. Treatment of MSD patient derived induced pluripotent stem cells (iPSC) differentiated into neuronal progenitor cells (NPC) resulted in a positive treatment response. Tazarotene and bexarotene act to ultimately increase the stability of FGE variants. The results lay the basis for future research on the development of a first therapeutic option for MSD patients.


Assuntos
Doença da Deficiência de Múltiplas Sulfatases , Humanos , Doença da Deficiência de Múltiplas Sulfatases/diagnóstico , Doença da Deficiência de Múltiplas Sulfatases/genética , Doença da Deficiência de Múltiplas Sulfatases/patologia , Bexaroteno , Avaliação Pré-Clínica de Medicamentos , Sulfatases/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre
5.
Mov Disord ; 38(1): 4-15, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36253921

RESUMO

Studies on dementia with Lewy bodies (DLB) have mainly focused on the degeneration of distinct cortical and subcortical regions related to the deposition of Lewy bodies. In view of the proposed trans-synaptic spread of the α-synuclein pathology, investigating the disease only in this segregated fashion would be detrimental to our understanding of its progression. In this systematic review, we summarize findings on structural and functional brain connectivity in DLB, as connectivity measures may offer better insights on how the brain is affected by the spread of the pathology. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched Web of Science, PubMed, and SCOPUS for relevant articles published up to November 1, 2021. Of 1215 identified records, we selected and systematically reviewed 53 articles that compared connectivity features between patients with DLB and healthy controls. Structural and functional magnetic resonance imaging, positron emission tomography, single-positron emission computer tomography, and electroencephalography assessments of patients revealed widespread abnormalities within and across brain networks in DLB. Frontoparietal, default mode, and visual networks and their connections to other brain regions featured the most consistent disruptions, which were also associated with core clinical features and cognitive impairments. Furthermore, graph theoretical measures revealed disease-related decreases in local and global network efficiency. This systematic review shows that structural and functional connectivity characteristics in DLB may be particularly valuable at early stages, before overt brain atrophy can be observed. This knowledge may help improve the diagnosis and prognosis in DLB as well as pinpoint targets for future disease-modifying treatments. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/patologia , Corpos de Lewy/patologia , Encéfalo/patologia , Eletroencefalografia , Tomografia por Emissão de Pósitrons , Doença de Alzheimer/patologia
6.
Neuroimage Rep ; 3(1)2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38606311

RESUMO

Language is an essential higher cognitive function in humans and is often affected by psychiatric and neurological disorders. Objective measures like the verbal fluency test are often used to determine language dysfunction. Recent applications of computational approaches broaden insights into language-related functions. In addition, individuals diagnosed with a psychiatric or neurological disorder also often report subjective difficulties in language-related functions. Therefore, we investigated the association between objective and subjective measures of language functioning, on the one hand, and inter-individual structural variations in language-related brain areas, on the other hand. We performed a Latent Semantic analysis (LSA) on a semantic verbal fluency task in 101 healthy adult participants. To investigate if these objective measures are associated with a subjective one, we examined assessed subjective natural tendency of interest in language-related activity with a study-specific questionnaire. Lastly, a voxel-based brain morphometry (VBM) was conducted to reveal associations between objective (LSA) measures and structural changes in language-related brain areas. We found a positive correlation between the LSA measure cosine similarity and the subjective interest in language. Furthermore, we found that higher cosine similarity corresponds to higher gray matter volume in the right cerebellum. The results suggest that people with higher interests in language access semantic knowledge in a more organized way exhibited by higher cosine similarity and have larger grey matter volume in the right cerebellum, when compared to people with lower interests. In conclusion, we demonstrate that there is inter-individual diverseness of accessing the semantic knowledge space and that it is associated with subjective language interests as well as structural differences in the right cerebellum.

7.
Neuroscience ; 479: 140-156, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34687795

RESUMO

Patients with schizophrenia present with various symptoms related to different domains. Abnormalities of auditory and visual perception are parts of a more general problem. Nevertheless, the relationship between the lifetime history of auditory verbal hallucination (AVH), one of the most prevalent symptoms in schizophrenia, and visuospatial deficits remains unclear. This study aimed to investigate differences in hemispheric involvement and visuospatial processing between healthy controls (HCs) and schizophrenia patients with and without AVHs. HCs (N = 20), schizophrenia patients with AVH (AVH group, N = 16), and schizophrenia patients without hallucinations (NH group, N = 10) participated in a 4-choice reaction task with lateralized stimuli. An event-related potential (ERP)-microstate approach was used to analyze ERP differences between the conditions and groups. The schizophrenia patients without hallucinations had slower responses than the HCs. An early visual N1 contralateral to stimulation side was prominent in all groups of participants but with decreased amplitude in the patients with schizophrenia, especially in the AVH group over the right hemisphere. The amplitude of P3b, a cognitive evaluation component, was also decreased in schizophrenia. Compared to AVH and HC groups, the patients in the NH group had altered microstate patterns: P3b was replaced by a novelty component, P3a. Although the difference between both patient groups was only based on the presence of AVHs, our findings indicated that patients had specific visuospatial deficits associated with a lifetime history of hallucinations: patients with AVHs showed early visual component alterations in the right hemisphere, and those without AVHs had more prominent visuospatial impairment.


Assuntos
Esquizofrenia , Potenciais Evocados , Alucinações , Humanos , Imageamento por Ressonância Magnética , Esquizofrenia/complicações , Percepção Visual
8.
Biochem J ; 478(17): 3221-3237, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34405855

RESUMO

The lysosomal degradation of heparan sulfate is mediated by the concerted action of nine different enzymes. Within this degradation pathway, Arylsulfatase G (ARSG) is critical for removing 3-O-sulfate from glucosamine, and mutations in ARSG are causative for Usher syndrome type IV. We developed a specific ARSG enzyme assay using sulfated monosaccharide substrates, which reflect derivatives of its natural substrates. These sulfated compounds were incubated with ARSG, and resulting products were analyzed by reversed-phase HPLC after chemical addition of the fluorescent dyes 2-aminoacridone or 2-aminobenzoic acid, respectively. We applied the assay to further characterize ARSG regarding its hydrolytic specificity against 3-O-sulfated monosaccharides containing additional sulfate-groups and N-acetylation. The application of recombinant ARSG and cells overexpressing ARSG as well as isolated lysosomes from wild-type and Arsg knockout mice validated the utility of our assay. We further exploited the assay to determine the sequential action of the different sulfatases involved in the lysosomal catabolism of 3-O-sulfated glucosamine residues of heparan sulfate. Our results confirm and extend the characterization of the substrate specificity of ARSG and help to determine the sequential order of the lysosomal catabolic breakdown of (3-O-)sulfated heparan sulfate.


Assuntos
Arilsulfatases/metabolismo , Heparitina Sulfato/análogos & derivados , Heparitina Sulfato/metabolismo , Lisossomos/metabolismo , Sulfatos/metabolismo , Acetilação , Animais , Arilsulfatases/genética , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Glucosamina/análogos & derivados , Glucosamina/metabolismo , Humanos , Camundongos , Camundongos Knockout , Especificidade por Substrato , Transfecção
9.
Bioconjug Chem ; 32(6): 1167-1174, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34060308

RESUMO

Multiple, site-specific protein conjugation is increasingly attractive for the generation of antibody-drug conjugates (ADCs). As it is important to control the number and position of cargoes in an ADC, position-selective generation of reactive sites in the protein of interest is required. Formylglycine (FGly) residues are generated by enzymatic conversion of cysteine residues embedded in a certain amino acid sequence motif with a formylglycine-generating enzyme (FGE). The addition of copper ions increases FGE activity leading to the conversion of cysteines within less readily accepted sequences. With this tuned enzyme activity, it is possible to address two different recognition sequences using two aerobic formylglycine-generating enzymes. We demonstrate an improved and facile strategy for the functionalization of a DARPin (designed ankyrin repeat protein) and the single-chain antibody scFv425-Fc, both directed against the epidermal growth factor receptor (EGFR). The single-chain antibody was conjugated with monomethyl auristatin E (MMAE) and carboxyfluorescein (CF) and successfully tested for receptor binding, internalization, and cytotoxicity in cell culture, respectively.


Assuntos
Enzimas/metabolismo , Glicina/análogos & derivados , Imunoconjugados/química , Imunoconjugados/metabolismo , Aerobiose , Repetição de Anquirina , Cobre/química , Fluoresceínas/química , Glicina/metabolismo , Oligopeptídeos/química
10.
Brain Sci ; 11(4)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33805063

RESUMO

Slow-wave sleep (SWS) has been shown to promote long-term consolidation of episodic memories in hippocampo-neocortical networks. Previous research has aimed to modulate cortical sleep slow-waves and spindles to facilitate episodic memory consolidation. Here, we instead aimed to modulate hippocampal activity during slow-wave sleep using transcranial direct current stimulation in 18 healthy humans. A pair-associate episodic memory task was used to evaluate sleep-dependent memory consolidation with face-occupation stimuli. Pre- and post-nap retrieval was assessed as a measure of memory performance. Anodal stimulation with 2 mA was applied bilaterally over the lateral temporal cortex, motivated by its particularly extensive connections to the hippocampus. The participants slept in a magnetic resonance (MR)-simulator during the recordings to test the feasibility for a future MR-study. We used a sham-controlled, double-blind, counterbalanced randomized, within-subject crossover design. We show that stimulation vs. sham significantly increased slow-wave density and the temporal coupling of fast spindles and slow-waves. While retention of episodic memories across sleep was not affected across the entire sample of participants, it was impaired in participants with below-average pre-sleep memory performance. Hence, bi-temporal anodal direct current stimulation applied during sleep enhanced sleep parameters that are typically involved in memory consolidation, but it failed to improve memory consolidation and even tended to impair consolidation in poor learners. These findings suggest that artificially enhancing memory-related sleep parameters to improve memory consolidation can actually backfire in those participants who are in most need of memory improvement.

11.
Neurosci Biobehav Rev ; 124: 54-62, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33482243

RESUMO

Noninvasive brain stimulation methods such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) are promising add-on treatments for a number of psychiatric conditions. Yet, some of the initial excitement is wearing off. Randomized controlled trials (RCT) have found inconsistent results. This inconsistency is suspected to be the consequence of variation in treatment effects and solvable by identifying responders in RCTs and individualizing treatment. However, is there enough evidence from RCTs that patients respond differently to treatment? This question can be addressed by comparing the variability in the active stimulation group with the variability in the sham group. We searched MEDLINE/PubMed and included all double-blinded, sham-controlled RCTs and crossover trials that used TMS or tDCS in adults with a unipolar or bipolar depression, bipolar disorder, schizophrenia spectrum disorder, or obsessive compulsive disorder. In accordance with the PRISMA guidelines to ensure data quality and validity, we extracted a measure of variability of the primary outcome. A total of 130 studies with 5748 patients were considered in the analysis. We calculated variance-weighted variability ratios for each comparison of active stimulation vs sham and entered them into a random-effects model. We hypothesized that treatment effect variability in TMS or tDCS would be reflected by increased variability after active compared with sham stimulation, or in other words, a variability ratio greater than one. Across diagnoses, we found only a minimal increase in variability after active stimulation compared with sham that did not reach statistical significance (variability ratio = 1.03; 95% CI, 0.97, 1.08, P = 0.358). In conclusion, this study found little evidence for treatment effect variability in brain stimulation, suggesting that the need for personalized or stratified medicine is still an open question.


Assuntos
Esquizofrenia , Estimulação Transcraniana por Corrente Contínua , Adulto , Análise de Variância , Encéfalo , Humanos , Esquizofrenia/terapia , Estimulação Magnética Transcraniana , Resultado do Tratamento
12.
Clin Psychol Psychother ; 28(4): 852-861, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33283948

RESUMO

The increasing prevalence of stress-related disorders such as burnout urges the need for specialized treatment approaches. Programmes combining psychotherapy and regenerative interventions emerge to be the most successful. However, evaluated therapy programmes are scarce and usually involve subjective symptom quantification without consideration of physiologic parameters. The aim of the present exploratory, single-group study was the multimodal investigation of the effectiveness of a specialized holistic therapy programme by assessing symptoms and biological markers of chronic stress. Seventy-one in-patients (39 men/32 women; age 46.8 ± 9.9 years) of a specialized burnout ward with the additional diagnosis of burnout (Z73.0) in conjunction with a main diagnosis of depressive disorder (F32 or F33) according to the International Classification of Diseases (ICD)-10 were included in the study. In addition to symptomatology, the stress-responsive biomarkers heart rate variability (HRV) and serum brain-derived neurotrophic factor (BDNF) were measured in patients at admittance to and discharge from the burnout ward applying a 6-week specialized treatment programme. At discharge, patients showed a significant reduction of symptom burden and a significant increase in serum BDNF, while HRV remained unchanged. The findings implicate that the therapy programme may have beneficial effects on symptomatology and neuroplasticity of patients with burnout. As therapy was often supplemented by psychopharmacological treatment, a relevant influence of antidepressant medication especially on BDNF has to be considered.


Assuntos
Esgotamento Psicológico/psicologia , Esgotamento Psicológico/terapia , Psicoterapia , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Psychiatry Res Neuroimaging ; 306: 111175, 2020 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-32919867
15.
Front Psychiatry ; 11: 836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973580

RESUMO

Despite being a commonly used protocol to treat major depressive disorder (MDD), the underlying mechanism of repetitive transcranial magnetic stimulation (rTMS) on dorsolateral prefrontal cortex (DLPFC) remains unclear. In the current study, we investigated the resting-state fMRI data of 100 healthy subjects by exploring three overlapping functional networks associated with the psychopathologically MDD-related areas (the nucleus accumbens, amygdala, and ventromedial prefrontal cortex). Our results showed that these networks converged at the bilateral DLPFC, which suggested that rTMS over DLPFC might improve MDD by remotely modulating the MDD-related areas synergistically. Additionally, they functionally converged at the DMPFC and bilateral insula which are known to be associated with MDD. These two areas could also be potential targets for rTMS treatment. Dynamic causal modelling (DCM) and Granger causality analysis (GCA) revealed that all pairwise connections among bilateral DLPFC, DMPFC, bilateral insula, and three psychopathologically MDD-related areas contained significant causality. The DCM results also suggested that most of the functional interactions between MDD-related areas and bilateral DLPFC, DMPFC, and bilateral insula can predominantly be explained by the effective connectivity from the psychopathologically MDD-related areas to the rTMS stimulation sites. Finally, we found the conventional functional connectivity to be a more representative measure to obtain connectivity parameters compared to GCA and DCM analysis. Our research helped inspecting the convergence of the functional networks related to a psychiatry disorder. The results identified potential targets for brain stimulation treatment and contributed to the optimization of patient-specific brain stimulation protocols.

16.
Biochem J ; 477(17): 3433-3451, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32856704

RESUMO

Mucopolysaccharidoses comprise a group of rare metabolic diseases, in which the lysosomal degradation of glycosaminoglycans (GAGs) is impaired due to genetically inherited defects of lysosomal enzymes involved in GAG catabolism. The resulting intralysosomal accumulation of GAG-derived metabolites consequently manifests in neurological symptoms and also peripheral abnormalities in various tissues like liver, kidney, spleen and bone. As each GAG consists of differently sulfated disaccharide units, it needs a specific, but also partly overlapping set of lysosomal enzymes to accomplish their complete degradation. Recently, we identified and characterized the lysosomal enzyme arylsulfatase K (Arsk) exhibiting glucuronate-2-sulfatase activity as needed for the degradation of heparan sulfate (HS), chondroitin sulfate (CS) and dermatan sulfate (DS). In the present study, we investigated the physiological relevance of Arsk by means of a constitutive Arsk knockout mouse model. A complete lack of glucuronate desulfation was demonstrated by a specific enzyme activity assay. Arsk-deficient mice show, in an organ-specific manner, a moderate accumulation of HS and CS metabolites characterized by 2-O-sulfated glucuronate moieties at their non-reducing ends. Pathophysiological studies reflect a rather mild phenotype including behavioral changes. Interestingly, no prominent lysosomal storage pathology like bone abnormalities were detected. Our results from the Arsk mouse model suggest a new although mild form of mucopolysacharidose (MPS), which we designate MPS type IIB.


Assuntos
Arilsulfatases/metabolismo , Sulfatos de Condroitina/metabolismo , Heparitina Sulfato/metabolismo , Mucopolissacaridoses/metabolismo , Animais , Arilsulfatases/genética , Sulfatos de Condroitina/genética , Ativação Enzimática , Heparitina Sulfato/genética , Camundongos , Camundongos Knockout , Mucopolissacaridoses/genética
17.
Chembiochem ; 21(24): 3580-3593, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-32767537

RESUMO

Formylglycine-generating enzymes specifically oxidize cysteine within the consensus sequence CxPxR to Cα -formylglycine (FGly). This noncanonical electrophilic amino acid can subsequently be addressed selectively by bioorthogonal hydrazino-iso-Pictet-Spengler (HIPS) or Knoevenagel ligation to attach payloads like fluorophores or drugs to proteins to obtain a defined payload-to-protein ratio. However, the disadvantages of these conjugation techniques include the need for a large excess of conjugation building block, comparably low reaction rates and limited stability of FGly-containing proteins. Therefore, functionalized clickable HIPS and tandem Knoevenagel building blocks were synthesized, conjugated to small proteins (DARPins) and subsequently linked to strained alkyne-containing payloads for protein labeling. This procedure allowed the selective bioconjugation of one or two DBCO-carrying payloads with nearly stoichiometric amounts at low concentrations. Furthermore, an azide-modified tandem Knoevenagel building block enabled the synthesis of branched PEG linkers and the conjugation of two fluorophores, resulting in an improved signal-to-noise ratio in live-cell fluorescence-imaging experiments targeting the EGF receptor.


Assuntos
Azidas/química , Reagentes de Ligações Cruzadas/química , Receptores ErbB/análise , Corantes Fluorescentes/química , Glicina/análogos & derivados , Reagentes de Ligações Cruzadas/síntese química , Corantes Fluorescentes/síntese química , Glicina/química , Humanos , Estrutura Molecular , Imagem Óptica , Células Tumorais Cultivadas
18.
J Inherit Metab Dis ; 43(6): 1298-1309, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32749716

RESUMO

Multiple sulfatase deficiency (MSD) is an ultra-rare neurodegenerative disorder caused by pathogenic variants in SUMF1. This gene encodes formylglycine-generating enzyme (FGE), a protein required for sulfatase activation. The clinical course of MSD results from additive effect of each sulfatase deficiency, including metachromatic leukodystrophy (MLD), several mucopolysaccharidoses (MPS II, IIIA, IIID, IIIE, IVA, VI), chondrodysplasia punctata, and X-linked ichthyosis. While it is known that affected individuals demonstrate a complex and severe phenotype, the genotype-phenotype relationship and detailed clinical course is unknown. We report on 35 cases enrolled in our retrospective natural history study, n = 32 with detailed histories. Neurologic function was longitudinally assessed with retrospective scales. Biochemical and computational modeling of novel SUMF1 variants was performed. Genotypes were classified based on predicted functional change, and each individual was assigned a genotype severity score. The median age at symptom onset was 0.25 years; median age at diagnosis was 2.7 years; and median age at death was 13 years. All individuals demonstrated developmental delay, and only a subset of individuals attained ambulation and verbal communication. All subjects experienced an accumulating systemic symptom burden. Earlier age at symptom onset and severe variant pathogenicity correlated with poor neurologic outcomes. Using retrospective deep phenotyping and detailed variant analysis, we defined the natural history of MSD. We found that attenuated cases can be distinguished from severe cases by age of onset, attainment of ambulation, and genotype. Results from this study can help inform prognosis and facilitate future study design.


Assuntos
Leucodistrofia Metacromática/genética , Mucopolissacaridoses/genética , Doença da Deficiência de Múltiplas Sulfatases/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Adolescente , Criança , Pré-Escolar , Feminino , Genótipo , Glicina/análogos & derivados , Glicina/genética , Glicina/metabolismo , Humanos , Lactente , Internacionalidade , Leucodistrofia Metacromática/patologia , Masculino , Mucopolissacaridoses/patologia , Doença da Deficiência de Múltiplas Sulfatases/patologia , Mutação , Fenótipo , Doenças Raras , Estudos Retrospectivos , Sulfatases/deficiência , Sulfatases/genética
19.
J Alzheimers Dis ; 76(4): 1461-1475, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32651312

RESUMO

BACKGROUND: Semantic memory impairments in semantic dementia are attributed to atrophy and functional disruption of the anterior temporal lobes. In contrast, the posterior medial temporal neurodegeneration found in Alzheimer's disease is associated with episodic memory disturbance. The two dementia subtypes share hippocampal deterioration, despite a relatively spared episodic memory in semantic dementia. OBJECTIVE: To unravel mutual and divergent functional alterations in Alzheimer's disease and semantic dementia, we assessed functional connectivity between temporal lobe regions in Alzheimer's disease (n = 16), semantic dementia (n = 23), and healthy controls (n = 17). METHODS: In an exploratory study, we used a functional parcellation of the temporal cortex to extract time series from 66 regions for correlation analysis. RESULTS: Apart from differing connections between Alzheimer's disease and semantic dementia that yielded reduced functional connectivity, we identified a common pathway between the right anterior temporal lobe and the right orbitofrontal cortex in both dementia subtypes. This disconnectivity might be related to social knowledge deficits as part of semantic memory decline. However, such interpretations are preferably made in a holistic context of disease-specific semantic impairments and functional connectivity changes. CONCLUSION: Despite a major limitation owed to unbalanced databases between study groups, this study provides a preliminary picture of the brain's functional disconnectivity in Alzheimer's disease and semantic dementia. Future studies are needed to replicate findings of a common pathway with consistent diagnostic criteria and neuropsychological evaluation, balanced designs, and matched data MRI acquisition procedures.


Assuntos
Doença de Alzheimer/patologia , Atrofia/patologia , Demência Frontotemporal/psicologia , Hipocampo/patologia , Lobo Temporal/patologia , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Transtornos da Memória/patologia , Transtornos da Memória/psicologia , Memória Episódica , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/fisiopatologia
20.
Neuroimage Clin ; 27: 102269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413810

RESUMO

The perception of faces and consequent social inferences are fundamental for interpersonal communication. While facial expression is important for interindividual communication, constitutional and acquired features are crucial for basic emotions of attraction or repulsion. An emotional bias in face processing has been shown in schizophrenia, but the neurobiological mechanisms are unclear. Studies on the interaction between face processing and the emotional state of healthy individuals may help to elucidate the pathogenesis of the paranoid syndrome in psychosis. This study addressed facial attractiveness and paranoid ideas in a non-clinical population. Using functional magnetic resonance imaging (fMRI), we investigated neural activation patterns of 99 healthy subjects during the passive perception of a dynamic presentation of faces with different attractiveness. We found that the perceived attractiveness of faces was linked to the activity of face processing and limbic regions including the fusiform gyrus, amygdala, and prefrontal areas. Paranoid beliefs interacted with perceived attractiveness in these regions resulting in a higher response range and increased activation after the presentation of unattractive faces. However, no behavioral interactions between reported subjective attractiveness and paranoid beliefs were found. The results showed that increased activation of limbic brain regions is linked to paranoid beliefs. Since similar correlations were found in clinical populations with paranoid syndromes, we suggest a dimension of emotional dysregulation ranging from subclinical paranoid beliefs to paranoid schizophrenia.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Adolescente , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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