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1.
BMC Biol ; 20(1): 17, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027047

RESUMO

BACKGROUND: Cellular prion protein (PrPC) is a cell surface GPI-anchored protein, usually known for its role in the pathogenesis of human and animal prionopathies. However, increasing knowledge about the participation of PrPC in prion pathogenesis contrasts with puzzling data regarding its natural physiological role. PrPC is expressed in a number of tissues, including at high levels in the nervous system, especially in neurons and glial cells, and while previous studies have established a neuroprotective role, conflicting evidence for a synaptic function has revealed both reduced and enhanced long-term potentiation, and variable observations on memory, learning, and behavior. Such evidence has been confounded by the absence of an appropriate knock-out mouse model to dissect the biological relevance of PrPC, with some functions recently shown to be misattributed to PrPC due to the presence of genetic artifacts in mouse models. Here we elucidate the role of PrPC in the hippocampal circuitry and its related functions, such as learning and memory, using a recently available strictly co-isogenic Prnp0/0 mouse model (PrnpZH3/ZH3). RESULTS: We performed behavioral and operant conditioning tests to evaluate memory and learning capabilities, with results showing decreased motility, impaired operant conditioning learning, and anxiety-related behavior in PrnpZH3/ZH3 animals. We also carried in vivo electrophysiological recordings on CA3-CA1 synapses in living behaving mice and monitored spontaneous neuronal firing and network formation in primary neuronal cultures of PrnpZH3/ZH3 vs wildtype mice. PrPC absence enhanced susceptibility to high-intensity stimulations and kainate-induced seizures. However, long-term potentiation (LTP) was not enhanced in the PrnpZH3/ZH3 hippocampus. In addition, we observed a delay in neuronal maturation and network formation in PrnpZH3/ZH3 cultures. CONCLUSION: Our results demonstrate that PrPC promotes neuronal network formation and connectivity. PrPC mediates synaptic function and protects the synapse from excitotoxic insults. Its deletion may underlie an epileptogenic-susceptible brain that fails to perform highly cognitive-demanding tasks such as associative learning and anxiety-like behaviors.


Assuntos
Proteínas Priônicas , Príons , Animais , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Camundongos , Camundongos Knockout , Proteínas Priônicas/metabolismo , Príons/metabolismo
2.
Neuropathol Appl Neurobiol ; 46(7): 654-672, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32255227

RESUMO

AIMS: Most individuals with AD neuropathological changes have co-morbidities which have an impact on the integrity of the WM. This study analyses oligodendrocyte and myelin markers in the frontal WM in a series of AD cases without clinical or pathological co-morbidities. METHODS: From a consecutive autopsy series, 206 cases had neuropathological changes of AD; among them, only 33 were AD without co-morbidities. WM alterations were first evaluated in coronal sections of the frontal lobe in every case. Then, RT-qPCR and immunohistochemistry were carried out in the frontal WM of AD cases without co-morbidities to analyse the expression of selected oligodendrocyte and myelin markers. RESULTS: WM demyelination was more marked in AD with co-morbidities when compared with AD cases without co-morbidities. Regarding the later, mRNA expression levels of MBP, PLP1, CNP, MAG, MAL, MOG and MOBP were preserved at stages I-II/0-A when compared with middle-aged (MA) individuals, but significantly decreased at stages III-IV/0-C. This was accompanied by reduced expression of NG2 and PDGFRA mRNA, reduced numbers of NG2-, Olig2- and HDAC2-immunoreactive cells and reduced glucose transporter immunoreactivity. Partial recovery of some of these markers occurred at stages V-VI/B-C. CONCLUSIONS: The present observations demonstrate that co-morbidities have an impact on WM integrity in the elderly and in AD, and that early alterations in oligodendrocytes and transcription of genes linked to myelin proteins in WM occur in AD cases without co-morbidities. These are followed by partial recovery attempts at advanced stages. These observations suggest that oligodendrocytopathy is part of AD.


Assuntos
Doença de Alzheimer/patologia , Proteínas da Mielina/metabolismo , Oligodendroglia/patologia , Substância Branca/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Feminino , Lobo Frontal/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas da Mielina/genética , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Oligodendroglia/metabolismo
3.
Neuropathol Appl Neurobiol ; 46(3): 240-254, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31216593

RESUMO

AIMS: In the search for blood-based biomarkers of neurodegenerative diseases, we characterized the concentration of total prion protein (t-PrP) in the plasma of neurodegenerative dementias. We aimed to assess its accuracy in this differential diagnostic context. METHODS: Plasma t-PrP was measured in 520 individuals including healthy controls (HC) and patients diagnosed with neurological disease control (ND), Alzheimer's disease (AD), sporadic Creutzfeldt-Jakob disease (sCJD), frontotemporal dementia (FTD), Lewy body dementia (LBD) and vascular dementia (VaD). Additionally, t-PrP was quantified in genetic prion diseases and iatrogenic CJD. The accuracy of t-PrP discriminating the diagnostic groups was evaluated and correlated with demographic, genetic and clinical data in prion diseases. Markers of blood-brain barrier impairment were investigated in sCJD brains. RESULTS: Compared to HC and ND, elevated plasma t-PrP concentrations were detected in sCJD, followed by FTD, AD, VaD and LBD. In sCJD, t-PrP was associated neither with age nor sex, but with codon 129 PRNP genotype. Plasma t-PrP concentrations correlated with cerebrospinal fluid (CSF) markers of neuro-axonal damage, but not with CSF t-PrP. In genetic prion diseases, plasma t-PrP was elevated in all type of mutations investigated. In sCJD brain tissue, extravasation of immunoglobulin G and the presence of swollen astrocytic end-feet around the vessels suggested leakage of blood-brain barrier as a potential source of increased plasma t-PrP. CONCLUSIONS: Plasma t-PrP is elevated in prion diseases regardless of aetiology. This pilot study opens the possibility to consider plasma t-PrP as a promising blood-based biomarker in the diagnostic of prion disease.


Assuntos
Biomarcadores/sangue , Demência/diagnóstico , Doenças Neurodegenerativas/diagnóstico , Doenças Priônicas/diagnóstico , Proteínas Priônicas/sangue , Adulto , Idoso , Demência/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/sangue , Doenças Priônicas/sangue
4.
Proc Biol Sci ; 286(1896): 20182900, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30963931

RESUMO

Studies testing linguistic laws outside language have provided important insights into the organization of biological systems. For example, patterns consistent with Zipf's law of abbreviation (which predicts a negative relationship between word length and frequency of use) have been found in the vocal and non-vocal behaviour of a range of animals, and patterns consistent with Menzerath's law (according to which longer sequences are made up of shorter constituents) have been found in primate vocal sequences, and in genes, proteins and genomes. Both laws have been linked to compression-the information theoretic principle of minimizing code length. Here, we present the first test of these laws in animal gestural communication. We initially did not find the negative relationship between gesture duration and frequency of use predicted by Zipf's law of abbreviation, but this relationship was seen in specific subsets of the repertoire. Furthermore, a pattern opposite to that predicted was seen in one subset of gestures-whole body signals. We found a negative correlation between number and mean duration of gestures in sequences, in line with Menzerath's law. These results provide the first evidence that compression underpins animal gestural communication, and highlight an important commonality between primate gesturing and language.


Assuntos
Comunicação Animal , Gestos , Pan troglodytes/psicologia , Animais , Feminino , Linguística , Masculino , Uganda
5.
Proc Natl Acad Sci U S A ; 113(19): E2750-8, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27091968

RESUMO

Identifying universal principles underpinning diverse natural systems is a key goal of the life sciences. A powerful approach in addressing this goal has been to test whether patterns consistent with linguistic laws are found in nonhuman animals. Menzerath's law is a linguistic law that states that, the larger the construct, the smaller the size of its constituents. Here, to our knowledge, we present the first evidence that Menzerath's law holds in the vocal communication of a nonhuman species. We show that, in vocal sequences of wild male geladas (Theropithecus gelada), construct size (sequence size in number of calls) is negatively correlated with constituent size (duration of calls). Call duration does not vary significantly with position in the sequence, but call sequence composition does change with sequence size and most call types are abbreviated in larger sequences. We also find that intercall intervals follow the same relationship with sequence size as do calls. Finally, we provide formal mathematical support for the idea that Menzerath's law reflects compression-the principle of minimizing the expected length of a code. Our findings suggest that a common principle underpins human and gelada vocal communication, highlighting the value of exploring the applicability of linguistic laws in vocal systems outside the realm of language.


Assuntos
Algoritmos , Linguística , Modelos Biológicos , Espectrografia do Som/métodos , Theropithecus/fisiologia , Vocalização Animal/fisiologia , Animais , Masculino , Fatores Sexuais , Medida da Produção da Fala/métodos
6.
Am J Gastroenterol ; 113(3): 396-403, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29460920

RESUMO

OBJECTIVES: The long-term safety of exposure to anti-tumor necrosis factor (anti-TNFα) drugs during pregnancy has received little attention. We aimed to compare the relative risk of severe infections in children of mothers with inflammatory bowel disease (IBD) who were exposed to anti-TNFα drugs in utero with that of children who were not exposed to the drugs. METHODS: Retrospective multicenter cohort study. Exposed cohort: children from mothers with IBD receiving anti-TNFα medication (with or without thiopurines) at any time during pregnancy or during the 3 months before conception. Non-exposed cohort: children from mothers with IBD not treated with anti-TNFα agents or thiopurines at any time during pregnancy or the 3 months before conception. The cumulative incidence of severe infections after birth was estimated using Kaplan-Meier curves, which were compared using the log-rank test. Cox-regression analysis was performed to identify potential predictive factors for severe infections in the offspring. RESULTS: The study population comprised 841 children, of whom 388 (46%) had been exposed to anti-TNFα agents. Median follow-up after delivery was 47 months in the exposed group and 68 months in the non-exposed group. Both univariate and multivariate analysis showed the incidence rate of severe infections to be similar in non-exposed and exposed children (1.6% vs. 2.8% per person-year, hazard ratio 1.2 (95% confidence interval 0.8-1.8)). In the multivariate analysis, preterm delivery was the only variable associated with a higher risk of severe infection (2.5% (1.5-4.3)). CONCLUSIONS: In utero exposure to anti-TNFα drugs does not seem to be associated with increased short-term or long-term risk of severe infections in children.


Assuntos
Antirreumáticos/uso terapêutico , Infecções/epidemiologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Nascimento Prematuro/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab/uso terapêutico , Adulto , Estudos de Casos e Controles , Certolizumab Pegol/uso terapêutico , Pré-Escolar , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Infliximab/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Gravidez , Modelos de Riscos Proporcionais , Estudos Retrospectivos
7.
Br J Dermatol ; 178(1): 198-206, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28733979

RESUMO

BACKGROUND: Naevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by developmental alterations and multiple basal cell carcinomas. Mutations in PTCH1, which encodes a membrane receptor for Sonic Hedgehog, are associated with the development of the disease. Most of them produce a truncated protein, which is unable to suppress Smoothened protein and continuously activates the downstream pathway. OBJECTIVES: We aimed to characterize 22 unrelated Spanish patients with NBCCS, the largest cohort with Gorlin syndrome reported to date in Spain. METHODS: Genomic analysis of PTCH1 was performed in patients with NBCCS and controls, and mutations were analysed using bioinformatics tools. RESULTS: We report for the first time two young patients, one each with uterus didelphys and ganglioneuroma, within the context of NBCCS. One patient showing a severe phenotype of the disease had developed basal cell carcinomas since childhood. Sanger sequencing of PTCH1 in this cohort identified 17 novel truncating mutations (11 frameshift, five nonsense and one mutation affecting an exon-intron splice site) and two novel missense mutations that were predicted to be pathogenic. The patients showed great clinical variability and inconsistent genotype-phenotype correlation, as seen in relatives carrying similar mutations. CONCLUSIONS: This study contributes to increase the pool of clinical manifestations of NBCCS, as well as increasing the number of pathogenic mutations identified in PTCH1 predisposing to the condition. The inconsistencies found between phenotype and genotype suggest the involvement of other modifying factors, genetic, epigenetic or environmental.


Assuntos
Síndrome do Nevo Basocelular/genética , Mutação/genética , Receptor Patched-1/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Síndrome do Nevo Basocelular/epidemiologia , Síndrome do Nevo Basocelular/patologia , Criança , Predisposição Genética para Doença/genética , Genótipo , Humanos , Pessoa de Meia-Idade , Fenótipo , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Espanha/epidemiologia , Adulto Jovem
8.
Biochim Biophys Acta Biomembr ; 1859(9 Pt B): 1604-1614, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28527668

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting millions of patients worldwide. Previous studies have demonstrated alterations in the lipid composition of lipid extracts from plasma and brain samples of AD patients. However, there is no consensus regarding the qualitative and quantitative changes of lipids in brains from AD patients. In addition, the recent developments in imaging mass spectrometry methods are leading to a new stage in the in situ analysis of lipid species in brain tissue slices from human postmortem samples. The present study uses the matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS), permitting the direct anatomical analysis of lipids in postmortem brain sections from AD patients, which are compared with the intensity of the lipid signal in samples from matched subjects with no neurological diseases. The frontal cortex samples from AD patients were classified in three groups based on Braak's histochemical criteria, ranging from non-cognitively impaired patients to those severely affected. The main results indicate a depletion of different sulfatide lipid species from the earliest stages of the disease in both white and gray matter areas of the frontal cortex. Therefore, the decrease in sulfatides in cortical areas could be considered as a marker of the disease, but may also indicate neurochemical modifications related to the pathogenesis of the disease. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.


Assuntos
Doença de Alzheimer/metabolismo , Lobo Frontal/química , Lipídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Sulfoglicoesfingolipídeos/análise
9.
Neuropathol Appl Neurobiol ; 43(5): 373-392, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28117912

RESUMO

AIMS: The present study analyses molecular characteristics of the locus coeruleus (LC) and projections to the amygdala and hippocampus at asymptomatic early and middle Braak stages of neurofibrillary tangle (NFT) pathology. METHODS: Immunohistochemistry, whole-transcriptome arrays and RT-qPCR in LC and western blotting in hippocampus and amygdala in a cohort of asymptomatic individuals at stages I-IV of NFT pathology were used. RESULTS: NFTs in the LC increased in parallel with colocalized expression of tau kinases, increased neuroketal adducts and decreased superoxide dismutase 1 in neurons with hyperphosphorylated tau and decreased voltage-dependent anion channel in neurons containing truncated tau were found. These were accompanied by increased microglia and AIF1, CD68, PTGS2, IL1ß, IL6 and TNF-α gene expression. Whole-transcriptome arrays revealed upregulation of genes coding for proteins associated with heat shock protein binding and genes associated with ATP metabolism and downregulation of genes coding for DNA-binding proteins and members of the small nucleolar RNAs family, at stage IV when compared with stage I. Tyrosine hydroxylase (TH) immunoreactivity was preserved in neurons of the LC, but decreased TH and increased α2A adrenergic receptor protein levels were found in the hippocampus and the amygdala. CONCLUSIONS: Complex alteration of several metabolic pathways occurs in the LC accompanying NFT formation at early and middle asymptomatic stages of NFT pathology. Dopaminergic/noradrenergic denervation and increased expression of α2A adrenergic receptor in the hippocampus and amygdala occur at first stage of NFT pathology, suggesting compensatory activation in the face of decreased adrenergic input occurring before clinical evidence of cognitive impairment and depression.


Assuntos
Locus Cerúleo/metabolismo , Locus Cerúleo/patologia , Emaranhados Neurofibrilares/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Hum Mol Genet ; 22(16): 3296-305, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23604518

RESUMO

X-linked adrenoleukodystrophy (X-ALD) is an inherited metabolic disorder of the nervous system characterized by axonopathy in spinal cords and/or cerebral demyelination, adrenal insufficiency and accumulation of very long-chain fatty acids (VLCFAs) in plasma and tissues. The disease is caused by malfunction of the ABCD1 gene, which encodes a peroxisomal transporter of VLCFAs or VLCFA-CoA. In the mouse, Abcd1 loss causes late onset axonal degeneration in the spinal cord, associated with locomotor disability resembling the most common phenotype in patients, adrenomyeloneuropathy. We have formerly shown that an excess of the VLCFA C26:0 induces oxidative damage, which underlies the axonal degeneration exhibited by the Abcd1(-) mice. In the present study, we sought to investigate the noxious effects of C26:0 on mitochondria function. Our data indicate that in X-ALD patients' fibroblasts, excess of C26:0 generates mtDNA oxidation and specifically impairs oxidative phosphorylation (OXPHOS) triggering mitochondrial ROS production from electron transport chain complexes. This correlates with impaired complex V phosphorylative activity, as visualized by high-resolution respirometry on spinal cord slices of Abcd1(-) mice. Further, we identified a marked oxidation of key OXPHOS system subunits in Abcd1(-) mouse spinal cords at presymptomatic stages. Altogether, our results illustrate some of the mechanistic intricacies by which the excess of a fatty acid targeted to peroxisomes activates a deleterious process of oxidative damage to mitochondria, leading to a multifaceted dysfunction of this organelle. These findings may be of relevance for patient management while unveiling novel therapeutic targets for X-ALD.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Adrenoleucodistrofia/metabolismo , Ácidos Graxos/farmacologia , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Peroxissomos/metabolismo , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Animais , Encéfalo/metabolismo , Células Cultivadas , DNA Mitocondrial , Fibroblastos/metabolismo , Radicais Livres/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/genética , Oxirredução , Estresse Oxidativo , Medula Espinal/metabolismo
11.
J Neural Transm (Vienna) ; 122(7): 941-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25113170

RESUMO

Human post-mortem brain tissue, mostly provided by brain banks, is precious because most human neurodegenerative diseases are restricted in their complete forms to human beings. However, the agonal state, post-mortem delay between death and tissue processing, variable vulnerability of chromatin, RNAs, proteins and metabolites can compromise the usability of the tissue material. Such factors must be considered and assessed in every experimental approach. The use of controls for comparative purposes to analyze diseased cases is crucial as the basic conditions of controls must be the same as those encountered in problem cases. Age, gender, region, hemisphere, and clear characterisation of objective neuropathological changes (e.g., Alzheimer's disease stages of Braak and Braak) in matching controls and problem cases must be considered in every study, and data must be clearly specified when presenting materials and methods in publications. Additional care must be taken regarding atypical neurodegenerative alterations, concomitant pathologies, and systemic diseases, together with drug consumption and treatments. The absence of neurological and mental symptoms and signs, although a sine qua non condition, is not sufficient to match control and problem cases for research.


Assuntos
Envelhecimento/patologia , Encéfalo/patologia , Doenças Neurodegenerativas/patologia , Bancos de Tecidos , Fatores Etários , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Mudanças Depois da Morte , Fatores Sexuais , Fatores de Tempo
12.
J Neural Transm (Vienna) ; 122(7): 1069-76, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25596843

RESUMO

The role of neuroinflammation in the pathogenesis of neurodegenerative diseases has become more evident in recent years. Research on the etiology and pathogenesis of sporadic Alzheimer's disease (AD) has focused on the role of chemokines such as CX3CL1, on the triggering receptors expressed by myeloid cells (TREMs), especially TREM2, and on the transcription factor/nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPARγ). Here we analyzed the expression levels of CX3CL1, TREM2, and PPARγ in tissue homogenates from human brain regions that have different degrees of vulnerability to neuropathological AD-related changes to obtain insights into the pathogenesis and progression of AD. We found that CX3CL1 and TREM2, two genes related to neuroinflammation, are more highly expressed in brain regions with pronounced vulnerability to AD-related changes, such as the hippocampus, and that the expression levels reflect the course of the disease, whereas regions with low vulnerability to AD, seemed generally less affected by neuroinflammation. Furthermore, our results support previous findings of significantly higher CX3CL1 plasma levels in patients with mild to moderate AD than in patients with severe AD. Thus, CX3CL1 should be considered as promising additional marker for the early diagnosis of AD and underlines once more, the involvement of the neuroinflammation in the pathogenesis of this neurodegenerative disease.


Assuntos
Doença de Alzheimer , Encéfalo/metabolismo , Quimiocinas CXC/genética , Expressão Gênica/fisiologia , Glicoproteínas de Membrana/genética , PPAR gama/genética , Receptores Imunológicos/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Análise de Variância , Encéfalo/patologia , Estudos de Casos e Controles , Quimiocinas CXC/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , PPAR gama/metabolismo , RNA Mensageiro , Receptores Imunológicos/metabolismo
13.
Stat Appl Genet Mol Biol ; 13(6): 633-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25503672

RESUMO

Menzerath's law, the tendency of Z (the mean size of the parts) to decrease as X (the number of parts) increases, is found in language, music and genomes. Recently, it has been argued that the presence of the law in genomes is an inevitable consequence of the fact that Z=Y/X, which would imply that Z scales with X as Z ∼ 1/X. That scaling is a very particular case of Menzerath-Altmann law that has been rejected by means of a correlation test between X and Y in genomes, being X the number of chromosomes of a species, Y its genome size in bases and Z the mean chromosome size. Here we review the statistical foundations of that test and consider three non-parametric tests based upon different correlation metrics and one parametric test to evaluate if Z ∼ 1/X in genomes. The most powerful test is a new non-parametric one based upon the correlation ratio, which is able to reject Z ∼ 1/X in nine out of 11 taxonomic groups and detect a borderline group. Rather than a fact, Z ∼ 1/X is a baseline that real genomes do not meet. The view of Menzerath-Altmann law as inevitable is seriously flawed.


Assuntos
Algoritmos , Modelos Estatísticos
14.
Artigo em Inglês | MEDLINE | ID: mdl-38821379

RESUMO

INTRODUCTION: Hemorrhoidal pathology is the most frequent proctological problem with a prevalence of 44% of the adult population. The most effective treatment is surgery but it also has the highest postoperative pain rate with moderate to severe pain rates of 30-40% during the first 24-48 hours. Here lies the importance of seeking measures to improve this situation, such as the pudendal nerve block with local anesthetic. However, the variability of the pudendal nerve sometimes makes its blockade ineffective and for this reason nerve location methods are sought to achieve a higher rate of success. The main aim of the study is to compare pain in the immediate postoperative period (24 h) after hemorrhoidectomy in patients with pudendal nerve block guided by anatomical references and guided by neurostimulation. METHODS: The present project proposes the performance of a single-center, triple-blind, randomized clinical trial of efficacy, carried out under conditions of routine clinical practice. Patients over 18 years old with hemorrhoids refractory to medical treatment, symptomatic grade III-IV and grade II hemorrhoids that do not respond to conservative procedures in a third level hospital in Spain and that are subsidiaries of surgery in major ambulatory surgery will be included. Demographic variables, variables on hemorrhoidal pathology, details of surgery, verbal numeric pain scale in the preoperative period and surgical complications will be collected. RESULTS: Not avaliable until the end of the study. CONCLUSIONS: The pudendal nerve block guided by anatomical landmarks has been shown to be useful in postoperative pain control after hemorrhoidectomy although the use of the neurostimulator has not been well studied and we believe it may improve outcom.

15.
Neuropathol Appl Neurobiol ; 39(2): 166-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22471883

RESUMO

AIMS: Frontotemporal lobar degeneration with Pick bodies (Pick's disease) is characterized by the presence of tau immunoreactive spherical structures in the cytoplasm of neurones. In view of confusion about the molecular pathology of Pick's disease, we aimed to evaluate the spectrum of tau pathology and concomitant neurodegeneration-associated protein depositions in the characteristically affected hippocampus. METHODS: We evaluated immunoreactivity (IR) for tau (AT8, 3R, 4R), α-synuclein, TDP43, p62, and ubiquitin in the hippocampus, entorhinal and temporal cortex in 66 archival cases diagnosed neuropathologically as Pick's disease. RESULTS: Mean age at death was 68.2 years (range 49-96). Fifty-two (79%) brains showed 3R immunoreactive spherical inclusions in the granule cells of the dentate gyrus. These typical cases presented mainly with the behavioural variant of frontotemporal dementia, followed by progressive aphasia, mixed syndromes or early memory disturbance. α-Synuclein IR was seen only in occasional spherical tau-positive inclusions, TDP-43 IR was absent, and 4R IR was present only as neurofibrillary tangles in pyramidal neurones. Aß IR was observed in 16 cases; however, the overall level of Alzheimer's disease-related alterations was mainly low or intermediate (n = 3). Furthermore, we identified six cases with unclassifiable tauopathy. CONCLUSIONS: (i) Pick's disease may occur also in elderly patients and is characterized by a relatively uniform pathology with 3R tau inclusions particularly in the granule cells of dentate gyrus; (ii) even minor deviation from these morphological criteria suggests a different disorder; and (iii) immunohistological revision of archival cases expands the spectrum of tauopathies that require further classification.


Assuntos
Hipocampo/metabolismo , Hipocampo/patologia , Doença de Pick/metabolismo , Doença de Pick/patologia , Tauopatias/metabolismo , Tauopatias/patologia , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Pick/classificação , Tauopatias/classificação
16.
Biomacromolecules ; 14(10): 3570-80, 2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-24004423

RESUMO

Poly(propylene imine) (PPI) glycodendrimers are promising candidates as drug carriers and antiamyloidogenic and antiprionic agents. In this study the anti-ß-amyloid capacity of PPI glycodendrimers of the fourth and fifth generations was investigated in vitro and in vivo. We assessed distinct PPI glycodendrimers including G4mDS and G5mDS, with electroneutral maltose shell, and G4mOS and G4m-IIIOS, with cationic maltose or maltotriose shell. Our results show that in vitro PPI maltose dendrimers reduce the toxicity of Aß(1-42). However, only the electroneutral maltose dendrimers G4mDS and G5mDS reduce the toxicity of Alzheimer's disease brain extracts in SH-SY5Y neuroblastoma cells. PPI maltose dendrimers with electroneutral or cationic surface penetrate the cytoplasm of cultured cells, and they reach the brain when administered intranasally. Both cationic G4mOS and electroneutral G4mDS are able to modify the total burden of ß-amyloid in APP/PS1 mice. The studied dendrimers did not reverse memory impairment in APP/PS1 mice following chronic administration; moreover, cationic G4mOS caused cognitive decline in nontransgenic mice. In spite of the capacity of G4mDS and G4mOS to cross the blood-brain barrier and modulate Aß aggregation in APP/PS1 mice, further studies are needed to learn how to reduce the harmful effects of maltose dendrimers in vivo.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/metabolismo , Dendrímeros/farmacologia , Glicoconjugados/farmacologia , Polipropilenos/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Administração Intranasal , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros/administração & dosagem , Dendrímeros/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glicoconjugados/administração & dosagem , Glicoconjugados/química , Humanos , Masculino , Maltose/química , Camundongos , Camundongos Transgênicos , Tamanho da Partícula , Polipropilenos/administração & dosagem , Polipropilenos/química , Proteínas Serina-Treonina Quinases/genética , Relação Estrutura-Atividade , Propriedades de Superfície , Células Tumorais Cultivadas
17.
ArXiv ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37873006

RESUMO

Linguistic laws, the common statistical patterns of human language, have been investigated by quantitative linguists for nearly a century. Recently, biologists from a range of disciplines have started to explore the prevalence of these laws beyond language, finding patterns consistent with linguistic laws across multiple levels of biological organisation, from molecular (genomes, genes, and proteins) to organismal (animal behaviour) to ecological (populations and ecosystems). We propose a new conceptual framework for the study of linguistic laws in biology, comprising and integrating distinct levels of analysis, from description to prediction to theory building. Adopting this framework will provide critical new insights into the fundamental rules of organisation underpinning natural systems, unifying linguistic laws and core theory in biology.

18.
Sci Total Environ ; 864: 161131, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36566864

RESUMO

In this work, we have studied the main species involved in determining total dissolved nitrogen (TDN) in water samples for accommodating a variety of quantitation methodologies to portable instruments and with the goal to achieve in situ analysis. The rise of water eutrophication is becoming an ecological problem in the world and TDN contributes markedly to this. Traditionally the several forms of DN are measured in the laboratory using conventional instrumentation from grab samples, but their analysis in place and in real time is a current demand. Inorganic nitrogen: NO3-, NO2- and NH4+, and organic nitrogen, such as amino nitrogen were tested here. For nitrate that presents native UV absorption suitable for direct water analysis, a portable optical fiber probe was compared with benchtop equipment and an in place analyzer. For nitrate, nitrite and ammonium, in situ solid devices that deliver reagents needed were tested and water color was measured by a smartphone coupled with a miniaturized optical fiber spectrometer and a miniaturized spectrometer or from images obtained and their RGB components. Amino nitrogen of some aromatic aminoacids with native fluorescence was followed by a portable optical fiber probe. Organic amino nitrogen and ammonium were determined by a portable luminometer and luminol supported in a measurement tube. Moreover, a portable miniaturized liquid chromatograph was shown suitable for monitoring priority nitrogen environmental pollutants. All options provided suitable results in comparison with lab estimations and were useful for evaluating if the legislation is fulfilled for the variety of tested waters. A discussion about the several portable options proposed for in place analysis, in function of the legislated determinations needed for each type of water was carried out.

19.
Neurobiol Dis ; 46(3): 508-26, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22737710

RESUMO

Parkinson disease (PD) is a systemic disease with variegated non-motor deficits and neurological symptoms, including impaired olfaction, autonomic failure, cognitive impairment and psychiatric symptoms, in addition to the classical motor symptoms. Many non-motor symptoms appear before or in parallel with motor deficits and then worsen with disease progression. Although there is a relationship, albeit not causal, between motor symptoms and the presence of Lewy bodies (LBs) and neurites filled with abnormal α-synuclein, other neurological alterations are independent of the amount of α-synuclein inclusions in neurons and neurites, thereby indicating that different mechanisms probably converge in the degenerative process. This may apply to complex alterations interfering with olfactory and autonomic nervous systemfunctions, emotions, sleep regulation, and behavioral, cognitive and mental performance. Involvement of the cerebral cortex leading to impaired behavior and cognition is related to several convergent altered factors including: a. dopaminergic, noradrenergic, serotoninergic and cholinergic cortical innervation; b. synapses; c. cortical metabolism; d. mitochondrial function and energy production; e. oxidative damage; f. transcription; g. protein expression; h. lipid composition; and i. ubiquitin­proteasome system and autophagy, among others. This complex situation indicates that multiple subcellular failure in selected cell populations is difficult to reconcilewith a reductionistic scenario of a single causative cascade of events leading to non-motor symptoms in PD. Furthermore, these alterationsmay appear at early stages of the disease and may precede the appearance of substantial irreversible cell loss by years. These observations have important implications in the design of therapeutic approaches geared to prevention and treatment of PD.


Assuntos
Química Encefálica/fisiologia , Doença de Parkinson/metabolismo , Tonsila do Cerebelo/patologia , Tonsila do Cerebelo/fisiopatologia , Encéfalo/patologia , Química Encefálica/genética , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Progressão da Doença , Humanos , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/fisiopatologia , Transtornos Mentais/etiologia , Transtornos Mentais/fisiopatologia , Transtornos do Olfato/etiologia , Transtornos do Olfato/fisiopatologia , Doença de Parkinson/genética , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Disautonomias Primárias/etiologia , Disautonomias Primárias/fisiopatologia , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/fisiopatologia
20.
Neuropathol Appl Neurobiol ; 38(2): 153-61, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21726270

RESUMO

BACKGROUND: In definite Creutzfeldt-Jakob disease (CJD), morphological and immunohistochemical patterns are useful to identify molecular subtypes. Severe cerebellar pathology and hippocampal involvement helps to identify VV subtypes. The rare VV1 variant (<1%), more frequent in young individuals, is additionally characterized by the presence of ballooned neurones in affected areas. In 1985, Cartier et al. described a family cluster of three individuals with an ataxic CJD form, showing, in addition to severe cerebellar and hippocampal involvement, the presence of frequent Hirano bodies (HB) in CA1 pyramidal neurones. HB are frequently found in aged individuals with Alzheimer pathology although they are not a specific finding. AIMS AND METHODS: In this study, we evaluated the presence of HB in hippocampi of 54 genetically and molecularly characterized CJD cases, aiming to elucidate whether additional morphological features could be helpful to point to molecular subtypes. RESULTS: We identified nine cases (four VV1, one out of three MV2K, three out of six MV2K+2C and one MV carrying a 96-base pair insertion) with abundant, partly bizarre and clustered HB in CA1 sector, not observed in other subtypes. The presence of HB was independent of hippocampal involvement by the disease itself. CONCLUSIONS: Clusters of abundant HB might be found in rare CJD subtypes such as VV1, MV2K/MV2K+2C and some genetic cases. In addition to histopathological and PrP immunohistochemical deposition patterns, their presence might be a useful additional morphologic feature that could point to the molecular subtype, especially when genetic and/or Western blot analyses are not available.


Assuntos
Encéfalo/patologia , Síndrome de Creutzfeldt-Jakob/classificação , Síndrome de Creutzfeldt-Jakob/patologia , Hipocampo/patologia , Proteínas 14-3-3/líquido cefalorraquidiano , Adulto , Fatores Etários , Idoso , Western Blotting , Encéfalo/metabolismo , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas PrPSc/metabolismo
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