RESUMO
Pterygium is a multifactorial disease in which UV-B is speculated to play a key role by inducing oxidative stress and phototoxic DNA damage. In search for candidate molecules that are useful for justifying the intense epithelial proliferation observed in pterygium, our attention has been focused on Insulin-like Growth Factor 2 (IGF-2), mainly detected in embryonic and fetal somatic tissues, which regulate metabolic and mitogenic functions. The binding between IGF-2 and its receptor Insulin-like Growth Factor 1 Receptor (IGF-1R) activates the PI3K-AKT pathway, which leads to the regulation of cell growth, differentiation, and the expression of specific genes. Since IGF2 is regulated by parental imprinting, in different human tumors, the IGF2 Loss of Imprinting (LOI) results in IGF-2- and IGF2-derived intronic miR-483 overexpression. Based on these activities, the purpose of this study was to investigate the overexpression of IGF-2, IGF-1R, and miR-483. Using an immunohistochemical approach, we demonstrated an intense colocalized epithelial overexpression of IGF-2 and IGF-1R in most pterygium samples (Fisher's exact test, p = 0.021). RT-qPCR gene expression analysis confirmed IGF2 upregulation and demonstrated miR-483 expression in pterygium compared to normal conjunctiva (253.2-fold and 12.47-fold, respectively). Therefore, IGF-2/IGF-1R co-expression could suggest their interplay through the two different paracrine/autocrine IGF-2 routes for signaling transfer, which would activate the PI3K/AKT signaling pathway. In this scenario, miR-483 gene family transcription might synergically reinforce IGF-2 oncogenic function through its boosting pro-proliferative and antiapoptotic activity.
Assuntos
MicroRNAs , Pterígio , Humanos , Proliferação de Células , Túnica Conjuntiva/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismoRESUMO
Alzheimer's disease (AD) is the leading cause of dementia, but the pathogenetic factors are not yet well known, and the relationships between brain and systemic biochemical derangements and disease onset and progression are unclear. We aim to focus on blood biomarkers for an accurate prognosis of the disease. We used a dataset characterized by longitudinal findings collected over the past 10 years from 90 AD patients. The dataset included 277 observations (both clinical and biochemical ones, encompassing blood analytes encompassing routine profiles for different organs, together with immunoinflammatory and oxidative markers). Subjects were grouped into four severity classes according to the Clinical Dementia Rating (CDR) Scale: mild (CDR = 0.5 and CDR = 1), moderate (CDR = 2), severe (CDR = 3) and very severe (CDR = 4 and CDR = 5). Statistical models were used for the identification of potential blood markers of AD progression. Moreover, we employed the Pathfinder tool of the Reactome database to investigate the biological pathways in which the analytes of interest could be involved. Statistical results reveal an inverse significant relation between four analytes (high-density cholesterol, total cholesterol, iron and ferritin) with AD severity. In addition, the Reactome database suggests that such analytes could be involved in pathways that are altered in AD progression. Indeed, the identified blood markers include molecules that reflect the heterogeneous pathogenetic mechanisms of AD. The combination of such blood analytes might be an early indicator of AD progression and constitute useful therapeutic targets.
Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Progressão da Doença , Biomarcadores , Índice de Gravidade de Doença , Colesterol , Testes NeuropsicológicosRESUMO
Various metals have been associated with the pathogenesis of Alzheimer's disease (AD), principally heavy metals that are environmental pollutants (such as As, Cd, Hg, and Pb) and essential metals whose homeostasis is disturbed in AD (such as Cu, Fe, and Zn). Although there is evidence of the involvement of these metals in AD, further research is needed on their mechanisms of toxicity. To further assess the involvement of heavy and essential metals in AD pathogenesis, we compared cerebrospinal fluid (CSF) AD biomarkers to macro- and microelements measured in CSF and plasma. We tested if macro- and microelements' concentrations (heavy metals (As, Cd, Hg, Ni, Pb, and Tl), essential metals (Na, Mg, K, Ca, Fe, Co, Mn, Cu, Zn, and Mo), essential non-metals (B, P, S, and Se), and other non-essential metals (Al, Ba, Li, and Sr)) are associated with CSF AD biomarkers that reflect pathological changes in the AD brain (amyloid ß1-42, total tau, phosphorylated tau isoforms, NFL, S100B, VILIP-1, YKL-40, PAPP-A, and albumin). We used inductively coupled plasma mass spectroscopy (ICP-MS) to determine macro- and microelements in CSF and plasma, and enzyme-linked immunosorbent assays (ELISA) to determine protein biomarkers of AD in CSF. This study included 193 participants (124 with AD, 50 with mild cognitive impairment, and 19 healthy controls). Simple correlation, as well as machine learning algorithms (redescription mining and principal component analysis (PCA)), demonstrated that levels of heavy metals (As, Cd, Hg, Ni, Pb, and Tl), essential metals (Ca, Co, Cu, Fe, Mg, Mn, Mo, Na, K, and Zn), and essential non-metals (P, S, and Se) are positively associated with CSF phosphorylated tau isoforms, VILIP-1, S100B, NFL, and YKL-40 in AD.
Assuntos
Doença de Alzheimer , Mercúrio , Metais Pesados , Humanos , Proteína 1 Semelhante à Quitinase-3 , Doença de Alzheimer/líquido cefalorraquidiano , Cádmio , Peptídeos beta-Amiloides , Chumbo , Metais Pesados/metabolismo , Biomarcadores/líquido cefalorraquidianoRESUMO
The climate change induced global warming, and in particular the increased frequency and intensity of heat waves, have been linked to health problems. Among them, scientific works have been reporting an increased incidence of neurological diseases, encompassing also neurodegenerative ones, such as Dementia of Alzheimer's type, Parkinson's Disease, and Motor Neuron Diseases. Although the increase in prevalence of neurodegenerative diseases is well documented by literature reports, the link between global warming and the enhanced prevalence of such diseases remains elusive. This is the main theme of our work, which aims to examine the connection between high temperature exposure and neurodegenerative diseases. Firstly, we evaluate the influence of high temperatures exposure on the pathophysiology of these disorders. Secondly, we discuss its effects on the thermoregulation, already compromised in affected patients, and its interference with processes of excitotoxicity, oxidative stress and neuroinflammation, all of them related with neurodegeneration. Finally, we investigate chronic versus acute stressors on body warming, and put forward a possible interpretation of the beneficial or detrimental effects on the brain, which is responsible for the incidence or progression of neurological disorders.
Assuntos
Mudança Climática , Aquecimento Global , Doenças Neurodegenerativas , Temperatura Alta , Humanos , Doenças Neurodegenerativas/epidemiologiaRESUMO
Stemness and apoptosis may highlight the dichotomy between regeneration and demise in the complex pathway proceeding from ontogenesis to the end of life. In the last few years, the concept has emerged that the same microRNAs (miRNAs) can be concurrently implicated in both apoptosis-related mechanisms and cell differentiation. Whether the differentiation process gives rise to the architecture of brain areas, any long-lasting perturbation of miRNA expression can be related to the occurrence of neurodevelopmental/neuropathological conditions. Moreover, as a consequence of neural stem cell (NSC) transformation to cancer stem cells (CSCs), the fine modulation of distinct miRNAs becomes necessary. This event implies controlling the expression of pro/anti-apoptotic target genes, which is crucial for the management of neural/neural crest-derived CSCs in brain tumors, neuroblastoma, and melanoma. From a translational point of view, the current progress on the emerging miRNA-based neuropathology therapeutic applications and antitumor strategies will be disclosed and their advantages and shortcomings discussed.
Assuntos
Apoptose , Diferenciação Celular , MicroRNAs/genética , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neurais/patologia , Animais , Humanos , Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/metabolismoRESUMO
While histological analysis represents a powerful tool for the classification of melanocytic lesions as benign or malignant, a clear-cut distinction between a nevus and a melanoma is sometimes a challenging step of the diagnostic process. The immunohistochemical detection of tyrosinase, cardinal melanogenic enzyme during melanocytic maturation, has often been helpful in formulating a differential diagnosis due to the peculiar staining pattern in nevocytes compared with melanoma cells. Tyrosinase distribution in nevi appears to overlap with the cytoarchitectural changes observable within these lesions, that result in epidermal or superficial dermal nevocytes being larger and strongly expressing melanocytic differentiation antigens, such as tyrosinase, compared with deeper dermal nevus cells. Our study aimed to evaluate the immunohistochemical expression pattern of tyrosinase in different histological types of acquired dysplastic melanocytic nevi, including junctional, compound, and intradermal nevi. Moreover, to estimate whether in nevocytes the expression of tyrosinase was associated with their differentiation state, we investigated the expression of two recognized markers of pluripotency, CD34 and nestin. In all examined nevi, our analysis revealed a remarkable immunoreactivity for tyrosinase in junctional and superficial dermal nevocytes and a decreasing gradient of staining in dermal nevocytes, up to become negative in deeper dermis. Meanwhile, junctional and dermal nevocytes were lacking in CD34 protein. Furthermore, nestin immunostaining showed an opposite distribution compared with tyrosinase, leading us to look into the tyrosinase/nestin expression pattern in melanocytic nevus as a tool to better understand the final stages of differentiation of melanocyte precursors toward their ultimate anatomical site into the epidermis.
Assuntos
Diferenciação Celular , Melanócitos/química , Melanócitos/patologia , Monofenol Mono-Oxigenase/análise , Nestina/análise , Nevo Pigmentado/química , Nevo Pigmentado/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanócitos/metabolismo , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/biossíntese , Nestina/biossíntese , Nevo Pigmentado/metabolismo , Adulto JovemRESUMO
MicroRNAs, also called miRNAs or simply miR-, represent a unique class of non-coding RNAs that have gained exponential interest during recent years because of their determinant involvement in regulating the expression of several genes. Despite the increasing number of mature miRNAs recognized in the human species, only a limited proportion is engaged in the ontogeny of the central nervous system (CNS). miRNAs also play a pivotal role during the transition of normal neural stem cells (NSCs) into tumor-forming NSCs. More specifically, extensive studies have identified some shared miRNAs between NSCs and neural cancer stem cells (CSCs), namely miR-7, -124, -125, -181 and miR-9, -10, -130. In the context of NSCs, miRNAs are intercalated from embryonic stages throughout the differentiation pathway in order to achieve mature neuronal lineages. Within CSCs, under a different cellular context, miRNAs perform tumor suppressive or oncogenic functions that govern the homeostasis of brain tumors. This review will draw attention to the most characterizing studies dealing with miRNAs engaged in neurogenesis and in the tumoral neural stem cell context, offering the reader insight into the power of next generation miRNA-targeted therapies against brain malignances.
Assuntos
MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular/genética , Perfilação da Expressão Gênica , Humanos , Células-Tronco Neoplásicas/patologia , Neurogênese/genética , TranscriptomaRESUMO
Purpose: Telocytes (TCs) are peculiar interstitial cells, characterized by their typical elongated and interconnected processes called telopodes. TCs are supposed to contribute to maintain tissue homeostasis but also to be involved in the pathophysiology of many disorders. The aim of the study was to identify TCs in pterygium, a chronic condition of bulbar conjunctiva, and to examine possible differences in TCs in terms of immunophenotype and/or localization between pterygium and normal conjunctiva, to evaluate the possible involvement of TCs in pathogenesis of pterygium. Methods: The analysis of the immunophenotype of TCs was performed on a group of 40 formalin-fixed and paraffin-embedded primary pterygium and ten bulbar conjunctiva samples. We examined with immunohistochemistry the expression of 11 commercially available antibodies (PDGFRα, CD34, c-kit, nestin, vimentin, α-SMA, laminin, S100, VEGF, CD133, and CD31) and with double immunofluorescence the concomitant expression of PDGFRα and CD34, and PDGFRα and nestin. In addition, we performed an ultrastructural study with transmission electron microscopy (TEM) on a group of five pterygium and three conjunctiva biopsy specimens. Results: TCs, ultrastructurally identified according to their "moniliform" prolongations, were localized underneath the epithelium along the basement membrane, around the vessels, and near the nerves and scattered in the stroma. In contrast, TCs, as fibroblasts, were almost absent in the fibrotic areas. In pterygium and normal conjunctiva, the TCs shared the same distribution pattern, except a marked TC hyperplasia detected in pterygium. Moreover, in pterygium, the immunohistochemical analysis of TCs showed a strong immunoreactivity to PDGFRα, CD34, and nestin. This result was confirmed with double immunofluorescence labeling, revealing that in pterygium stromal TCs always showed a PDGFRα+/nestin+ and PDGFRα+/CD34+ immunophenotype. Furthermore, moderate staining to vimentin and VEGF was detected, but only a small number of cells were weakly immunoreactive to laminin and S100. Only adventitial TCs of the perivascular sheaths exhibited strong immunoreactivity to α-SMA. Conversely, despite showing mild immunoreactivity to PDGFRα and CD34, the TCs in normal conjunctiva did not show any immunoreactivity to nestin and VEGF. Moreover, in pterygium and conjunctiva, the TCs were always negative for c-kit. Conclusions: Because of the distribution and immunophenotype, TCs in pterygium may represent a subpopulation of relatively immature cells with regenerative potential. In addition, the expression of nestin may suggest possible involvement of TCs as active players in the regeneration of ultraviolet-damaged stroma and vascular remodeling. The fibrotic transformation in the cicatricial area may stand for a breakdown of the regenerative process.
Assuntos
Túnica Conjuntiva/anormalidades , Imunofenotipagem/métodos , Pterígio/genética , Telócitos/classificação , Telócitos/metabolismo , Antígeno AC133/genética , Antígeno AC133/metabolismo , Actinas/genética , Actinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Túnica Conjuntiva/cirurgia , Feminino , Formaldeído , Expressão Gênica , Humanos , Imuno-Histoquímica , Laminina/genética , Laminina/metabolismo , Masculino , Pessoa de Meia-Idade , Nestina/genética , Nestina/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pterígio/metabolismo , Pterígio/patologia , Pterígio/cirurgia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas S100/genética , Proteínas S100/metabolismo , Telócitos/patologia , Fixação de Tecidos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vimentina/genética , Vimentina/metabolismoRESUMO
Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome characterized by initial predominant visuoperceptual deficits followed by a progressive decline in other cognitive functions. This syndrome has not been as thoroughly described as other dementias, particularly from a neuropsychological evolution perspective with only a few studies describing the evolution of its cognitive progression. In this investigation we review the literature on this rare condition and we perform a 7-year neuropsychological and neuroradiological follow-up of a 64-year-old man with PCA. The subject's deficits initially appeared in his visuoperceptual skills with later affectation appearing in language and other cognitive functions, this being coherent with the patient's parieto-temporal atrophy evolution.
Assuntos
Encefalopatias/complicações , Córtex Cerebral/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Transtornos da Percepção/etiologia , Atrofia/complicações , Atrofia/diagnóstico por imagem , Encefalopatias/genética , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/genética , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Transtornos da Percepção/genética , Percepção Visual/fisiologiaRESUMO
Multiple sclerosis is a demyelinating inflammatory disease that affects the central nervous system. Its etiology is the result of a complex interaction between genetic and environmental factors that trigger a deregulated immune response, with the resulting inflammation and neuronal/axonal degeneration. Neuroinflammation is triggered when peripheral leukocytes migrate to the central nervous system and release cytokines such as interleukins 1 and 6 (IL-1 and 6) and tumor necrosis factor (TNF), which act on dwelling cells. The innate immune system plays an important role in the onset and progression of the disease by identifying molecular patterns associated with pathogens and damage, which modulate effector and regulatory functions of the cells where they are expressed, in order to direct the specific immune response. Th17 cells favor the disruption of the blood-brain barrier, which enables the migration of leukocytes to the central nervous system and the triggering of the inflammatory cascade; the Th1 profile (IL-1, IL-6) collaborates to perpetuate it. B-cell function is to produce antibodies and cytokines (IL-6, IL-12 and TFN). Knowledge on multiple sclerosis pathophysiology will enable the development of new therapeutic options that impact on natural history of the disease and its prognosis.
La esclerosis múltiple es una enfermedad inflamatoria desmielinizante que afecta el sistema nervioso central. Su etiología es el resultado de una compleja interacción entre factores genéticos y ambientales que desencadenan una respuesta inmune desregulada, con la consiguiente inflamación y degeneración neuronal/axonal. La neuroinflamación se desencadena cuando los leucocitos periféricos migran al sistema nervioso central y liberan citocinas como interleucinas 1 y 6 (IL-1, IL-6) y factor de necrosis tumoral (TNF), que actúan sobre células residentes del mismo. El sistema inmune innato desempeña un papel importante en el inicio y progresión de la enfermedad, mediante la identificación de patrones moleculares asociados con patógenos y daño, que modulan las funciones efectoras y reguladoras de las células donde se expresan, para dirigir la respuesta inmune específica. Las células Th17 favorecen la disrupción de la barrera hematoencefálica, que permite la migración de leucocitos al sistema nervioso central y desencadena la cascada de la inflamación; el perfil Th1 (IL-1, IL-6) colabora para perpetuarla. La función de las células B es la producción de anticuerpos y citocinas (IL-6, IL-12 y TFN). Conocer la fisiopatología de la esclerosis múltiple permitirá desarrollar nuevas opciones terapéuticas que impacten en la historia natural de la enfermedad y su pronóstico.
Assuntos
Citocinas/imunologia , Inflamação/fisiopatologia , Esclerose Múltipla/fisiopatologia , Animais , Barreira Hematoencefálica/metabolismo , Movimento Celular/fisiologia , Progressão da Doença , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Leucócitos/metabolismo , Esclerose Múltipla/imunologia , Prognóstico , Células Th17/imunologiaRESUMO
Epithelial-mesenchymal transition (EMT) has been suggested to have a driving role in the acquisition of a metastatic potential by melanoma cells. Important hallmarks of EMT include both E-cadherin downregulation and increased expression of N-cadherin. This switch in distinct classes of adhesion molecules leads melanoma cells to lose contact with adjacent keratinocytes and interact instead with stromal fibroblasts and endothelial cells, thus promoting dermal and vascular melanoma invasion. Consequently, tumor cells migrate to distant host tissues and establish metastases. A key regulator in the induction of EMT in melanoma is the Notch1 signaling pathway that, when activated, is prompt to upregulate N-cadherin expression. By means of this strategy, melanoma cells gain enhanced survival, proliferation and invasion properties, driving the tumor toward a more aggressive phenotype. On the basis of these statements, the present study aimed to investigate the possible association between N-cadherin and Notch1 presence in primary cutaneous melanomas and lymph node metastases. Our results from immunohistochemical analysis confirmed a positive correlation between N-cadherin and Notch1 presence in the same tumor samples. Moreover, this study highlighted that a concomitant high expression of N-cadherin and Notch1, both in primary lesions and in lymph node metastases, predicts an adverse clinical outcome in melanoma patients. Therefore, N-cadherin and Notch1 co-presence can be monitored as a predictive factor in early- and advanced-stage melanomas and open additional therapeutic targets for the restraint of melanoma metastasis.
Assuntos
Caderinas/análise , Transição Epitelial-Mesenquimal , Melanoma/química , Receptor Notch1/análise , Neoplasias Cutâneas/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Caderinas/biossíntese , Criança , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/diagnóstico , Melanoma/metabolismo , Pessoa de Meia-Idade , Receptor Notch1/biossíntese , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo , Adulto JovemRESUMO
BACKGROUND: Imbalance of gamma aminobutyric acid (GABA) and related modulators has been implicated as an important factor in the pathogenesis of amyotrophic lateral sclerosis (ALS), which is also known as motor neuron disease (MND). In this context, the role and mechanism of action of gabapentin and baclofen have been extensively investigated, although with conflicting results. This is the first systematic review to assess clinical trials of GABA modulators for the treatment of ALS. OBJECTIVES: To examine the efficacy of gabapentin, baclofen, or other GABA modulators in delaying the progression of ALS, and to evaluate adverse effects of these interventions SEARCH METHODS: On 16 August 2016, we searched the Cochrane Neuromuscular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL Plus, AMED, and LILACS. In addition, we checked the bibliographies of the trials found in order to identify any other trials, and contacted trial authors to identify relevant unpublished results or additional clinical trials. On 30 August 2016, we searched two clinical trials registries. SELECTION CRITERIA: Types of studies: double-blind randomized controlled trials (RCTs) or quasi-RCTsTypes of participants: adults with a diagnosis of probable or definite ALSTypes of interventions: gabapentin, baclofen, or other GABA modulators compared with placebo, no treatment, or each otherPrimary outcome: survival at one year from study enrollmentSecondary outcomes: individual rate of decline of maximum voluntary isometric contraction (MVIC), expressed as arm megascore; rate of decline of per cent predicted forced vital capacity (FVC); rate of decline of ALS Functional Rating Scale (ALSFRS); health-related quality of life; survival evaluated by pooling hazards; and adverse events DATA COLLECTION AND ANALYSIS: At least two review authors independently checked titles and abstracts identified by the searches. The review authors obtained and independently analyzed original individual participant data from each included study; additional review authors and the Cochrane Neuromuscular Managing Editor checked the outcome data. Two authors independently assessed the risk of bias in included studies. Data collection and analysis: At least two review authors independently checked titles and abstracts identified by the searches. The review authors obtained and independently analyzed original individual participant data from each included study; additional review authors and the Cochrane Neuromuscular Managing Editor checked the outcome data. Two authors independently assessed the risk of bias in included studies. MAIN RESULTS: We identified two double-blind RCTs of gabapentin treatment in ALS for inclusion in this review. We found no eligible RCTs of baclofen or other GABA modulators. The selected studies were phase II and phase III trials, which lasted six and nine months, respectively. They were highly comparable because both were comparisons of oral gabapentin and placebo, performed by the same investigators. The trials enrolled 355 participants with ALS: 80 in the gabapentin group and 72 in the placebo group in the first (phase II) trial and 101 in the gabapentin group and 102 in the placebo group in the second (phase III) trial. Neither trial was long enough to report survival at one year, which was our primary outcome. We found little or no difference in estimated one-year survival between the treated group and the placebo group (78% versus 77%, P = 0.63 by log-rank test; high-quality evidence). We also found little or no difference in the rate of decline of MVIC expressed as arm megascore, or rate of FVC decline (high-quality evidence). One trial investigated monthly decline in the ALSFRS and quality of life measured using the 12-Item Short Form Survey (SF-12) and found little or no difference between groups (moderate-quality evidence). The trials reported similar adverse events. Complaints that were clearly elevated in those taking gabapentin, based on analyses of the combined data, were light-headedness, drowsiness, and limb swelling (high-quality evidence). Fatigue and falls occurred more frequently with gabapentin than with placebo in one trial, but when we combined the data for fatigue from both trials, there was no clear difference between the groups. We assessed the overall risk of bias in the included trials as low. AUTHORS' CONCLUSIONS: According to high-quality evidence, gabapentin is not effective in treating ALS. It does not extend survival, slow the rate of decline of muscle strength, respiratory function and, based on moderate-quality evidence, probably does not improve quality of life or slow monthly decline in the ALSFRS. Other GABA modulators have not been studied in randomized trials.
Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , GABAérgicos/uso terapêutico , Ácido gama-Aminobutírico/uso terapêutico , Adulto , Esclerose Lateral Amiotrófica/mortalidade , Baclofeno/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , GABAérgicos/efeitos adversos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Ácido gama-Aminobutírico/efeitos adversosRESUMO
Insulin-like peptides (ILPs) play highly conserved roles in development and physiology. Most animal genomes encode multiple ILPs. Here we identify mechanisms for how the forty Caenorhabditis elegans ILPs coordinate diverse processes, including development, reproduction, longevity and several specific stress responses. Our systematic studies identify an ILP-based combinatorial code for these phenotypes characterized by substantial functional specificity and diversity rather than global redundancy. Notably, we show that ILPs regulate each other transcriptionally, uncovering an ILP-to-ILP regulatory network that underlies the combinatorial phenotypic coding by the ILP family. Extensive analyses of genetic interactions among ILPs reveal how their signals are integrated. A combined analysis of these functional and regulatory ILP interactions identifies local genetic circuits that act in parallel and interact by crosstalk, feedback and compensation. This organization provides emergent mechanisms for phenotypic specificity and graded regulation for the combinatorial phenotypic coding we observe. Our findings also provide insights into how large hormonal networks regulate diverse traits.
Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Insulina/genética , Receptor de Insulina/genética , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Redes Reguladoras de Genes , Insulina/metabolismo , Longevidade/genética , Fenótipo , Receptor de Insulina/metabolismo , Transdução de Sinais/genética , Somatomedinas/genética , Somatomedinas/metabolismoRESUMO
Quantitative imaging has become a vital technique in biological discovery and clinical diagnostics; a plethora of tools have recently been developed to enable new and accelerated forms of biological investigation. Increasingly, the capacity for high-throughput experimentation provided by new imaging modalities, contrast techniques, microscopy tools, microfluidics and computer controlled systems shifts the experimental bottleneck from the level of physical manipulation and raw data collection to automated recognition and data processing. Yet, despite their broad importance, image analysis solutions to address these needs have been narrowly tailored. Here, we present a generalizable formulation for autonomous identification of specific biological structures that is applicable for many problems. The process flow architecture we present here utilizes standard image processing techniques and the multi-tiered application of classification models such as support vector machines (SVM). These low-level functions are readily available in a large array of image processing software packages and programming languages. Our framework is thus both easy to implement at the modular level and provides specific high-level architecture to guide the solution of more complicated image-processing problems. We demonstrate the utility of the classification routine by developing two specific classifiers as a toolset for automation and cell identification in the model organism Caenorhabditis elegans. To serve a common need for automated high-resolution imaging and behavior applications in the C. elegans research community, we contribute a ready-to-use classifier for the identification of the head of the animal under bright field imaging. Furthermore, we extend our framework to address the pervasive problem of cell-specific identification under fluorescent imaging, which is critical for biological investigation in multicellular organisms or tissues. Using these examples as a guide, we envision the broad utility of the framework for diverse problems across different length scales and imaging methods.
Assuntos
Caenorhabditis elegans/citologia , Rastreamento de Células/métodos , Cabeça/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Animais , Aprendizado de Máquina , Imagem Multimodal/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Previous single-case reports in posterior cortical atrophy (PCA) have shown preserved nonconscious visual recognition despite the absence of explicit recognition. In this study, we investigated three levels of visual recognition in both a female patient with PCA and a control group during the presentation of neutral, positive, and negative affective stimuli. Our results confirmed the profile of impaired explicit recognition and intact psychophysiological responses in the patient. In addition, she was able to implicitly recognize the valence and intensity of arousal of these stimuli. We suggest that implicit emotional awareness may mediates explicit and psychophysiological recognition in PCA.
Assuntos
Córtex Cerebral/patologia , Emoções/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Nível de Alerta , Atrofia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
Carbonyl groups are known to form covalent adducts with endogenous proteins, but so far, their nematicidal mechanism of action of has been overlooked. The nematicidal activity of ten lactones was tested in vitro against the root knot nematodes Meloidogyne incognita and Meloidogynearenaria. In particular, the saturated lactones α-methylene-γ-butyrolactone or tulipaline A (1) and γ-butyrolactone (3) were active against M. incognita with an EC50/48h of 19.3±10.0 and 40.0±16.2mg/L respectively. Moreover the α, ß-unsaturated lactone 5,6-dihydro-2H-pyran-2-one (2) exhibited the strongest nematicidal activity against the two species with EC50/48h 14.5±5.3 and 21.2±9.7mg/L respectively. Here we propose that the toxic effects of lactones and aldehydes on M.incognita and M. arenaria might be a consequence of their vacuolar-type H(+)-ATPase (V-ATPase) inhibition activity; in fact α-methylene-γ-butyrolactone (1) and salicylaldehyde (12) produced an increased pH in lysosomal-like organelles on HeLa human cell line and this alteration was most likely related to a V-ATPase impairment.
Assuntos
4-Butirolactona/análogos & derivados , Antinematódeos/farmacologia , Proteínas de Helminto/antagonistas & inibidores , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Aldeídos/química , Aldeídos/farmacologia , Animais , Antinematódeos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HeLa , Proteínas de Helminto/metabolismo , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Lactonas/química , Lactonas/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Microscopia de Fluorescência , Estrutura Molecular , Organelas/efeitos dos fármacos , Organelas/metabolismo , Especificidade da Espécie , Relação Estrutura-Atividade , Tylenchoidea/classificação , Tylenchoidea/efeitos dos fármacos , Tylenchoidea/enzimologia , ATPases Vacuolares Próton-Translocadoras/metabolismoRESUMO
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons responsible for unintended or uncontrollable movements. Mutations in the leucine-rich repeat kinase 2 locus contribute to genetic forms of PD. The fruit fly Drosophila melanogaster carrying this mutation (LRRK2-Dm) is an in vivo model of PD that develops motor impairment and stands for an eligible non-mammalian paradigm to test novel therapeutic approaches. Dehydrozingerone (DHZ) is a natural phenolic compound isolated from ginger and presents anti-inflammatory, antioxidant and neuroprotective properties, making it a potential therapeutic target for PD. We administered DHZ and its C2-symmetric dimer (DHZ-DIM) at 0.5 and 1 mM for 14 and 21 days in the LRRK2-Dm, with the aim of assessing changes in rescuing motor behavior, brain dopaminergic neurons, mitochondria and synapses (T-bars). The shorter treatment with both molecules revealed efficacy at the higher dose, improving climbing behavior with a prevention of dopaminergic neuronal demise. After 21 days, a recovery of the motor disability, dopaminergic neuron loss, mitochondrial damage and T-bars failure was observed with the DHZ-DIM. Our data indicate that the DHZ-DIM exerts a more potent neuroprotective effect with respect to the monomer in LRRK2-Dm, prompting further investigation of these compounds in rodent models of PD.
Assuntos
Pessoas com Deficiência , Transtornos Motores , Fármacos Neuroprotetores , Doença de Parkinson , Estirenos , Animais , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Drosophila , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Drosophila melanogaster/genética , Neurônios Dopaminérgicos , Suplementos Nutricionais , MutaçãoRESUMO
G6PC3 deficiency is a monogenic immunometabolic disorder that causes syndromic congenital neutropenia. Patients display heterogeneous extra-hematological manifestations, contributing to delayed diagnosis. Here, we investigated the origin and functional consequence of the G6PC3 c.210delC variant found in patients of Mexican origin. Based on the shared haplotypes amongst carriers of the c.210delC mutation, we estimated that this variant originated from a founder effect in a common ancestor. Furthermore, by ancestry analysis, we concluded that it originated in the indigenous Mexican population. At the protein level, we showed that this frameshift mutation leads to an aberrant protein expression in overexpression and patient-derived cells. G6PC3 pathology is driven by the intracellular accumulation of the metabolite 1,5-anhydroglucitol-6-phosphate (1,5-AG6P) that inhibits glycolysis. We characterized how the variant c.210delC impacts glycolysis by performing extracellular flux assays on patient-derived cells. When treated with 1,5-anhydroglucitol (1,5-AG), the precursor to 1,5-AG6P, patient-derived cells exhibited markedly reduced engagement of glycolysis. Finally, we compared the clinical presentation of patients with the mutation c.210delC and all other G6PC3 deficient patients reported in the literature to date, and we found that c.210delC carriers display all prominent clinical features observed in prior G6PC3 deficient patients. In conclusion, G6PC3 c.210delC is a loss-of-function mutation that arose from a founder effect in the indigenous Mexican population. These findings may facilitate the diagnosis of additional patients in this geographical area. Moreover, the in vitro 1,5-AG-dependent functional assay used in our study could be employed to assess the pathogenicity of additional G6PC3 variants.
RESUMO
Background: G6PC3 deficiency is a rare genetic disorder that causes syndromic congenital neutropenia. It is driven by the intracellular accumulation of a metabolite named 1,5-anhydroglucitol-6-phosphate (1,5-AG6P) that inhibits glycolysis. Patients display heterogeneous extra-hematological manifestations, contributing to delayed diagnosis. Objective: The G6PC3 c.210delC variant has been identified in patients of Mexican origin. We set out to study the origin and functional consequence of this mutation. Furthermore, we sought to characterize the clinical phenotypes caused by it. Methods: Using whole-genome sequencing data, we conducted haplotype analysis to estimate the age of this allele and traced its ancestral origin. We examined how this mutation affected G6PC3 protein expression and performed extracellular flux assays on patient-derived cells to characterize how this mutation impacts glycolysis. Finally, we compared the clinical presentations of patients with the c.210delC mutation relative to other G6PC3 deficient patients published to date. Results: Based on the length of haplotypes shared amongst ten carriers of the G6PC3 c.210delC mutation, we estimated that this variant originated in a common ancestor of indigenous American origin. The mutation causes a frameshift that introduces a premature stop codon, leading to a complete loss of G6PC3 protein expression. When treated with 1,5-anhydroglucitol (1,5-AG), the precursor to 1,5-AG6P, patient-derived cells exhibited markedly reduced engagement of glycolysis. Clinically, c.210delC carriers display all the clinical features of syndromic severe congenital neutropenia type 4 observed in prior reports of G6PC3 deficiency. Conclusion: The G6PC3 c.210delC is a loss-of-function mutation that arose from a founder effect in the indigenous Mexican population. These findings may facilitate the diagnosis of additional patients in this geographical area. Moreover, the in vitro 1,5-AG-dependent functional assay used in our study could be employed to assess the pathogenicity of additional G6PC3 variants.