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INTRODUCTION: This study aimed to investigate the influence of the overall Alzheimer's disease (AD) genetic architecture on Down syndrome (DS) status, cognitive measures, and cerebrospinal fluid (CSF) biomarkers. METHODS: AD polygenic risk scores (PRS) were tested for association with DS-related traits. RESULTS: The AD risk PRS was associated with disease status in several cohorts of sporadic late- and early-onset and familial late-onset AD, but not in familial early-onset AD or DS. On the other hand, lower DS Mental Status Examination memory scores were associated with higher PRS, independent of intellectual disability and APOE (PRS including APOE, PRSAPOE , p = 2.84 × 10-4 ; PRS excluding APOE, PRSnonAPOE , p = 1.60 × 10-2 ). PRSAPOE exhibited significant associations with Aß42, tTau, pTau, and Aß42/40 ratio in DS. DISCUSSION: These data indicate that the AD genetic architecture influences cognitive and CSF phenotypes in DS adults, supporting common pathways that influence memory decline in both traits. HIGHLIGHTS: Examination of the polygenic risk of AD in DS presented here is the first of its kind. AD PRS influences memory aspects in DS individuals, independently of APOE genotype. These results point to an overlap between the genes and pathways that leads to AD and those that influence dementia and memory decline in the DS population. APOE ε4 is linked to DS cognitive decline, expanding cognitive insights in adults.
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Doença de Alzheimer , Disfunção Cognitiva , Síndrome de Down , Adulto , Humanos , Doença de Alzheimer/diagnóstico , Síndrome de Down/genética , Estratificação de Risco Genético , Apolipoproteínas E/genética , Fenótipo , Disfunção Cognitiva/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Cognição , Transtornos da Memória , Peptídeos beta-Amiloides/líquido cefalorraquidianoRESUMO
INTRODUCTION: Almost all individuals with Down syndrome (DS) will develop neuropathological features of Alzheimer's disease (AD). Understanding AD biomarker trajectories is necessary for DS-specific clinical interventions and interpretation of drug-related changes in the disease trajectory. METHODS: A total of 177 adults with DS from the Alzheimer's Biomarker Consortium-Down Syndrome (ABC-DS) underwent positron emission tomography (PET) and MR imaging. Amyloid-beta (Aß) trajectories were modeled to provide individual-level estimates of Aß-positive (A+) chronicity, which were compared against longitudinal tau change. RESULTS: Elevated tau was observed in all NFT regions following A+ and longitudinal tau increased with respect to A+ chronicity. Tau increases in NFT regions I-III was observed 0-2.5 years following A+. Nearly all A+ individuals had tau increases in the medial temporal lobe. DISCUSSION: These findings highlight the rapid accumulation of amyloid and early onset of tau relative to amyloid in DS and provide a strategy for temporally characterizing AD neuropathology progression that is specific to the DS population and independent of chronological age. HIGHLIGHTS: Longitudinal amyloid trajectories reveal rapid Aß accumulation in Down syndrome NFT stage tau was strongly associated with A+ chronicity Early longitudinal tau increases were observed 2.5-5 years after reaching A.
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Doença de Alzheimer , Síndrome de Down , Adulto , Humanos , Síndrome de Down/complicações , Proteínas tau , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Amiloide , Tomografia por Emissão de Pósitrons/métodos , BiomarcadoresRESUMO
Prior authorization criteria for Federal Drug Administration (FDA) approved immunotherapeutics, among the class of anti-amyloid monoclonal antibodies (mAbs), established by state drug formulary committees, are tailored for adults with late-onset Alzheimer's disease. This overlooks adults with Down syndrome (DS), who often experience dementia at a younger age and with different diagnostic assessment outcomes. This exclusion may deny DS adults access to potential disease-modifying treatments. To address this issue, an international expert panel convened to establish adaptations of prescribing criteria suitable for DS patients and parameters for access to Centers for Medicare & Medicaid Services (CMS) registries. The panel proposed mitigating disparities by modifying CMS and payer criteria to account for younger onset age, using alternative language and assessment instruments validated for cognitive decline in the DS population. The panel also recommended enhancing prescribing clinicians' diagnostic capabilities for DS and initiated awareness-raising activities within healthcare organizations. These efforts facilitated discussions with federal officials, aimed at achieving equity in access to anti-amyloid immunotherapeutics, with implications for national authorities worldwide evaluating these and other new disease-modifying therapeutics for Alzheimer's disease.
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Síndrome de Down , Humanos , Estados Unidos , Doença de Alzheimer/tratamento farmacológico , Adulto , Anticorpos Monoclonais/uso terapêutico , Imunoterapia/métodosRESUMO
Down's syndrome is associated with pathological ageing and a propensity for early-onset Alzheimer's disease. The early symptoms of dementia in people with Down's syndrome may reflect frontal lobe vulnerability to amyloid deposition. Auditory predictive processes rely on the bilateral auditory cortices with the recruitment of frontal cortices and appear to be impaired in pathologies characterized by compromised frontal lobe. Hence, auditory predictive processes were investigated to assess Down's syndrome pathology and its relationship with pathological ageing. An auditory electroencephalography (EEG) global-local paradigm was presented to the participants, in which oddball stimuli could either violate local or higher level global rules. We characterised predictive processes in individuals with Down's syndrome and their relationship with pathological ageing, with a focus on the EEG event-related potential called Mismatch Negativity (MMN) and the P300. In Down's syndrome, we also evaluated the EEG components as predictor of cognitive decline 1 year later. We found that predictive processes of detection of auditory violations are overall preserved in Down's syndrome but also that the amplitude of the MMN to local deviancies decreases with age. However, the 1-year follow-up of Down's syndrome found that none of the ERPs measures predicted subsequent cognitive decline. The present study provides a novel characterization of electrophysiological markers of local and global predictive processes in Down's syndrome.
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Doença de Alzheimer , Síndrome de Down , Adulto , Humanos , Síndrome de Down/diagnóstico , Síndrome de Down/patologia , Síndrome de Down/psicologia , Envelhecimento , EletroencefalografiaRESUMO
INTRODUCTION: Adults with Down syndrome (DS) are predisposed to Alzheimer's disease (AD) and reveal early amyloid beta (Aß) pathology in the brain. Positron emission tomography (PET) provides an in vivo measure of Aß throughout the AD continuum. Due to the high prevalence of AD in DS, there is need for longitudinal imaging studies of Aß to better characterize the natural history of Aß accumulation, which will aid in the staging of this population for clinical trials aimed at AD treatment and prevention. METHODS: Adults with DS (N = 79; Mean age (SD) = 42.7 (7.28) years) underwent longitudinal [C-11]Pittsburgh compound B (PiB) PET. Global Aß burden was quantified using the amyloid load metric (AßL). Modeled PiB images were generated from the longitudinal AßL data to visualize which regions are most susceptible to Aß accumulation in DS. AßL change was evaluated across Aß(-), Aß-converter, and Aß(+) groups to assess longitudinal Aß trajectories during different stages of AD-pathology progression. AßL change values were used to identify Aß-accumulators within the Aß(-) group prior to reaching the Aß(+) threshold (previously reported as 20 AßL) which would have resulted in an Aß-converter classification. With knowledge of trajectories of Aß(-) accumulators, a new cutoff of Aß(+) was derived to better identify subthreshold Aß accumulation in DS. Estimated sample sizes necessary to detect a 25% reduction in annual Aß change with 80% power (alpha 0.01) were determined for different groups of Aß-status. RESULTS: Modeled PiB images revealed the striatum, parietal cortex and precuneus as the regions with earliest detected Aß accumulation in DS. The Aß(-) group had a mean AßL change of 0.38 (0.58) AßL/year, while the Aß-converter and Aß(+) groups had change of 2.26 (0.66) and 3.16 (1.34) AßL/year, respectively. Within the Aß(-) group, Aß-accumulators showed no significant difference in AßL change values when compared to Aß-converter and Aß(+) groups. An Aß(+) cutoff for subthreshold Aß accumulation was derived as 13.3 AßL. The estimated sample size necessary to detect a 25% reduction in Aß was 79 for Aß(-) accumulators and 59 for the Aß-converter/Aß(+) group in DS. CONCLUSION: Longitudinal AßL changes were capable of distinguishing Aß accumulators from non-accumulators in DS. Longitudinal imaging allowed for identification of subthreshold Aß accumulation in DS during the earliest stages of AD-pathology progression. Detection of active Aß deposition evidenced by subthreshold accumulation with longitudinal imaging can identify DS individuals at risk for AD development at an earlier stage.
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Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagem , Síndrome de Down/complicações , Síndrome de Down/diagnóstico por imagem , Adulto , Doença de Alzheimer/etiologia , Doença de Alzheimer/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Progressão da Doença , Síndrome de Down/patologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Tomografia por Emissão de PósitronsRESUMO
BACKGROUND: Alzheimer's disease and its complications are the leading cause of death in adults with Down syndrome. Studies have assessed Alzheimer's disease in individuals with Down syndrome, but the natural history of biomarker changes in Down syndrome has not been established. We characterised the order and timing of changes in biomarkers of Alzheimer's disease in a population of adults with Down syndrome. METHODS: We did a dual-centre cross-sectional study of adults with Down syndrome recruited through a population-based health plan in Barcelona (Spain) and through services for people with intellectual disabilities in Cambridge (UK). Cognitive impairment in participants with Down syndrome was classified with the Cambridge Cognitive Examination for Older Adults with Down Syndrome (CAMCOG-DS). Only participants with mild or moderate disability were included who had at least one of the following Alzheimer's disease measures: apolipoprotein E allele carrier status; plasma concentrations of amyloid ß peptides 1-42 and 1-40 and their ratio (Aß1-42/1-40), total tau protein, and neurofilament light chain (NFL); tau phosphorylated at threonine 181 (p-tau), and NFL in cerebrospinal fluid (CSF); and one or more of PET with 18F-fluorodeoxyglucose, PET with amyloid tracers, and MRI. Cognitively healthy euploid controls aged up to 75 years who had no biomarker abnormalities were recruited from the Sant Pau Initiative on Neurodegeneration. We used a first-order locally estimated scatterplot smoothing curve to determine the order and age at onset of the biomarker changes, and the lowest ages at the divergence with 95% CIs are also reported where appropriate. FINDINGS: Between Feb 1, 2013, and June 28, 2019 (Barcelona), and between June 1, 2009, and Dec 31, 2014 (Cambridge), we included 388 participants with Down syndrome (257 [66%] asymptomatic, 48 [12%] with prodromal Alzheimer's disease, and 83 [21%] with Alzheimer's disease dementia) and 242 euploid controls. CSF Aß1-42/1-40 and plasma NFL values changed in individuals with Down syndrome as early as the third decade of life, and amyloid PET uptake changed in the fourth decade. 18F-fluorodeoxyglucose PET and CSF p-tau changes occurred later in the fourth decade of life, followed by hippocampal atrophy and changes in cognition in the fifth decade of life. Prodromal Alzheimer's disease was diagnosed at a median age of 50·2 years (IQR 47·5-54·1), and Alzheimer's disease dementia at 53·7 years (49·5-57·2). Symptomatic Alzheimer's disease prevalence increased with age in individuals with Down syndrome, reaching 90-100% in the seventh decade of life. INTERPRETATION: Alzheimer's disease in individuals with Down syndrome has a long preclinical phase in which biomarkers follow a predictable order of changes over more than two decades. The similarities with sporadic and autosomal dominant Alzheimer's disease and the prevalence of Down syndrome make this population a suitable target for Alzheimer's disease preventive treatments. FUNDING: Instituto de Salud Carlos III, Fundació Bancaria La Caixa, Fundació La Marató de TV3, Medical Research Council, and National Institutes of Health.
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Doença de Alzheimer/metabolismo , Biomarcadores/sangue , Síndrome de Down/complicações , Adulto , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Peptídeos beta-Amiloides/metabolismo , Amiloidose/diagnóstico por imagem , Amiloidose/patologia , Apolipoproteínas E/metabolismo , Estudos de Casos e Controles , Disfunção Cognitiva/psicologia , Estudos Transversais , Síndrome de Down/epidemiologia , Síndrome de Down/mortalidade , Síndrome de Down/psicologia , Fluordesoxiglucose F18/administração & dosagem , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons/métodos , Prevalência , Espanha/epidemiologia , Reino Unido/epidemiologia , Proteínas tau/metabolismoRESUMO
Improved medical care of individuals with Down syndrome (DS) has led to an increase in life expectancy to over the age of 60 years. In conjunction, there has been an increase in age-related co-occurring conditions including Alzheimer's disease (AD). Understanding the factors that underlie symptom and age of clinical presentation of dementia in people with DS may provide insights into the mechanisms of sporadic and DS-associated AD (DS-AD). In March 2019, the Alzheimer's Association, Global Down Syndrome Foundation and the LuMind IDSC Foundation partnered to convene a workshop to explore the state of the research on the intersection of AD and DS research; to identify research gaps and unmet needs; and to consider how best to advance the field. This article provides a summary of discussions, including noting areas of emerging science and discovery, considerations for future studies, and identifying open gaps in our understanding for future focus.
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Doença de Alzheimer/complicações , Síndrome de Down/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Síndrome de Down/metabolismo , HumanosRESUMO
Down's syndrome is a chromosomal disorder that invariably results in both intellectual disability and Alzheimer's disease neuropathology. However, only a limited number of studies to date have investigated intrinsic brain network organisation in people with Down's syndrome, none of which addressed the links between functional connectivity and Alzheimer's disease. In this cross-sectional study, we employed 11 C-Pittsburgh Compound-B (PiB) positron emission tomography in order to group participants with Down's syndrome based on the presence of fibrillar beta-amyloid neuropathology. We also acquired resting state functional magnetic resonance imaging data to interrogate the connectivity of the default mode network; a large-scale system with demonstrated links to Alzheimer's disease. The results revealed widespread positive connectivity of the default mode network in people with Down's syndrome (n = 34, ages 30-55, median age = 43.5) and a stark lack of anti-correlation. However, in contrast to typically developing controls (n = 20, ages 30-55, median age = 43.5), the Down's syndrome group also showed significantly weaker connections in localised frontal and posterior brain regions. Notably, while a comparison of the PiB-negative Down's syndrome group (n = 19, ages 30-48, median age = 41.0) to controls suggested that alterations in default mode connectivity to frontal brain regions are related to atypical development, a comparison of the PiB-positive (n = 15, ages 39-55, median age = 48.0) and PiB-negative Down's syndrome groups indicated that aberrant connectivity in posterior cortices is associated with the presence of Alzheimer's disease neuropathology. Such distinct profiles of altered connectivity not only further our understanding of the brain physiology that underlies these two inherently linked conditions but may also potentially provide a biomarker for future studies of neurodegeneration in people with Down's syndrome.
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Doença de Alzheimer/fisiopatologia , Conectoma , Síndrome de Down/fisiopatologia , Adulto , Doença de Alzheimer/diagnóstico por imagem , Amiloide , Compostos de Anilina , Radioisótopos de Carbono , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Estudos Transversais , Síndrome de Down/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , TiazóisRESUMO
Adults with Down syndrome (DS) are at a very high risk of developing early onset Alzheimer's disease (AD) due to trisomy of chromosome 21. AD is preceded by a prolonged prodromal "pre-clinical" phase presenting with clinical features that do not fulfil the diagnostic criteria for AD. It is important to clinically characterise this prodromal stage to help early detection of the disease as neuropathology of AD is almost universal by the fifth decade in DS. There is a lack of knowledge of the trajectory of decline associated with the onset of dementia in this population and early signs may be overlooked or misdiagnosed, negatively affecting the quality of life of those affected and the use of early pharmacological or psychosocial interventions. The objective of this systematic review is to evaluate the published literature on longitudinal data in order to identify the cognitive and behavioural changes occurring during the prodromal and early stages of AD in this population. Fifteen peer-reviewed articles met the inclusion criteria, including a total number of 831 participants, with the duration between baseline and follow up varying from 1 year to 47 years. Results suggest that, compared to the general population for which short-term (episodic) memory loss is the most common indicator associated with the onset of AD, in people with DS, executive dysfunction and Behavioural and Psychological Symptoms of Dementia (BPSD) are commonly observed during pre-clinical and early stages and may precede memory loss. The review highlights the importance of using a broad spectrum of assessments in the context of heterogeneity of symptoms. Theoretical and practical implications are discussed, as well as the need for further research.
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Demência/diagnóstico , Demência/etiologia , Síndrome de Down/complicações , Diagnóstico Precoce , Humanos , Estudos Longitudinais , Testes NeuropsicológicosRESUMO
INTRODUCTION: Adults with Down syndrome (DS) invariably develop Alzheimer's disease (AD) neuropathology. Understanding amyloid deposition in DS can yield crucial information about disease pathogenesis. METHODS: Forty-nine adults with DS aged 25-65 underwent positron emission tomography with Pittsburgh compound-B (PIB). Regional PIB binding was assessed with respect to age, clinical, and cognitive status. RESULTS: Abnormal PIB binding became evident from 39 years, first in striatum followed by rostral prefrontal-cingulo-parietal regions, then caudal frontal, rostral temporal, primary sensorimotor and occipital, and finally parahippocampal cortex, thalamus, and amygdala. PIB binding was related to age, diagnostic status, and cognitive function. DISCUSSION: PIB binding in DS, first appearing in striatum, began around age 40 and was strongly associated with dementia and cognitive decline. The absence of a substantial time lag between amyloid accumulation and cognitive decline contrasts to sporadic/familial AD and suggests this population's suitability for an amyloid primary prevention trial.
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Amiloide/metabolismo , Córtex Cerebral/metabolismo , Síndrome de Down/patologia , Adulto , Fatores Etários , Doença de Alzheimer/epidemiologia , Peptídeos beta-Amiloides/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Compostos RadiofarmacêuticosRESUMO
The Plasmodium is responsible for malaria which poses a major health threat, globally. This study is based on the estimation of the relative abundance of mosquitoes, and finding out the correlations of meteorological parameters (temperature, humidity and rainfall) with the abundance of mosquitoes. In addition, this study also focused on the use of nested PCR (species-specific nucleotide sequences of 18S rRNA genes) to explore the Plasmodium spp. in female Anopheles. In the current study, the percentage relative abundance of Culex mosquitoes was 57.65% and Anopheles 42.34% among the study areas. In addition, the highest number of mosquitoes was found in March in district Mandi Bahauddin at 21 °C (Tmax = 27, Tmin = 15) average temperature, 69% average relative humidity and 131 mm rainfall, and these climatic factors were found to affect the abundance of the mosquitoes, directly or indirectly. Molecular analysis showed that overall, 41.3% of the female Anopheles pools were positive for genus Plasmodium. Among species, the prevalence of Plasmodium (P.) vivax (78.1%) was significantly higher than P. falciparum (21.9%). This study will be helpful in the estimation of future risk of mosquito-borne diseases along with population dynamic of mosquitoes to enhance the effectiveness of vector surveillance and control programs.
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Anopheles , Malária , Mosquitos Vetores , Plasmodium , Reação em Cadeia da Polimerase , Animais , Anopheles/parasitologia , Anopheles/genética , Mosquitos Vetores/parasitologia , Mosquitos Vetores/genética , Reação em Cadeia da Polimerase/métodos , Feminino , Plasmodium/genética , Plasmodium/isolamento & purificação , Malária/epidemiologia , Malária/parasitologia , Malária/transmissão , RNA Ribossômico 18S/genética , Culex/parasitologia , Culex/genética , Humanos , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/genéticaRESUMO
Ultraviolet radiation (UVR) is the major exogenous agent that disturbs tissue homeostasis and hastens the onset of age-related phenotypes (photoaging). Exposure to UV-B radiation promotes apoptosis in human skin cells via induction of Reactive Oxygen Species (ROS)-mediated Endoplasmic Reticulum (ER) stress by activating the PERK-eIF2α-CHOP pathway, which plays a major role in exacerbating skin photoaging. Alleviating the production of ROS and boosting the antioxidant capacity of cells is the foremost therapeutic strategy to avert the repercussions of ultraviolet radiation exposure. In this study, we investigated the role of 3-(1'-methyltetrahydropyridinyl)-2,4-6-trihydroxy acetophenone (IIIM-8) in thwarting the UV-B-induced photoaging. We observed that IIIM-8 ameliorates UV-B-induced oxidative stress, ER stress, Loss of Mitochondrial membrane potential, MAPK activation and Inflammation in irradiated skin cells. Ultraviolet radiation-related damage to fibroblasts within the dermis leads to collagen degradation-the hallmark of photoaging. IIIM-8 substantially restored the synthesis of collagen and prevented its degradation via the downregulation of matrix metalloproteinases. Topical application of IIIM-8 prevented BALB/c mice skin from UV-B-induced leukocyte infiltration, epidermal thickening and disruption of Extracellular matrix components. Implying that IIIM-8 has a strong photoprotective property and has potential to be developed as a topical therapeutic/cosmeceutical agent against UV-B-induced photoaging.
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Envelhecimento da Pele , Animais , Camundongos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta/efeitos adversos , Camundongos Endogâmicos BALB C , Pele/metabolismo , Colágeno/metabolismo , Fibroblastos/metabolismoRESUMO
Exposure to Ultraviolet radiation or α-melanocyte-stimulating hormone (α-MSH) stimulates the Cyclic Adenosine Monophosphate/Protein Kinase A signalling pathway, which leads to the synthesis and deposition of melanin granules in the epidermis. Skin pigmentation is the major physiological defence against inimical effects of sunlight. However, excessive melanin production and accumulation can cause various skin hyperpigmentation disorders. The present study involved the identification of 3-(1'-methyltetrahydropyridinyl)-2,4-6-trihydroxy acetophenone (IIIM-8) as an inhibitor of melanogenesis, IIIM-8 significantly inhibited pigment production both in vitro and in vivo without incurring any cytotoxicity in Human Adult Epidermal Melanocytes (HAEM). IIIM-8 repressed melanin synthesis and secretion both at basal levels and in α-MSH stimulated cultured HAEM cells by decreasing the levels of Cyclic Adenosine Monophosphate (cAMP) and inhibiting the phosphorylation of cAMP response element-binding (CREB) protein, coupled with restoring the phosphorylation of CREB-regulated transcription coactivator 1 (CRTC1) and its nuclear exclusion in HAEM cells. This impeding effect correlates with diminished expression of master melanogenic proteins including microphthalmia-associated transcription factor (MITF), Tyrosinase (TYR), Tyrosinase related protein 1 (TRP1), and Tyrosinase related protein 2 (TRP2). Additionally, topical application of IIIM-8 induced tail depigmentation in C57BL/6J mice. Furthermore, IIIM-8 efficiently mitigated the effect of ultraviolet-B radiation on melanin synthesis in the auricles of C57BL/6J mice. This study demonstrates that IIIM-8 is an active anti-melanogenic agent against ultraviolet radiation-induced melanogenesis and other hyperpigmentation disorders.
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Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Hiperpigmentação , Adulto , Animais , Camundongos , Humanos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Melaninas , Monofenol Mono-Oxigenase/metabolismo , alfa-MSH/farmacologia , Raios Ultravioleta/efeitos adversos , Camundongos Endogâmicos C57BL , Melanócitos , Acetofenonas/farmacologia , Acetofenonas/metabolismo , Monofosfato de Adenosina/farmacologia , Heme/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Linhagem Celular Tumoral , Fatores de Transcrição/metabolismoRESUMO
The study of sex differences in Alzheimer's disease is increasingly recognized as a key priority in research and clinical development. People with Down syndrome represent the largest population with a genetic link to Alzheimer's disease (>90% in the 7th decade). Yet, sex differences in Alzheimer's disease manifestations have not been fully investigated in these individuals, who are key candidates for preventive clinical trials. In this double-centre, cross-sectional study of 628 adults with Down syndrome [46% female, 44.4 (34.6; 50.7) years], we compared Alzheimer's disease prevalence, as well as cognitive outcomes and AT(N) biomarkers across age and sex. Participants were recruited from a population-based health plan in Barcelona, Spain, and from a convenience sample recruited via services for people with intellectual disabilities in England and Scotland. They underwent assessment with the Cambridge Cognitive Examination for Older Adults with Down Syndrome, modified cued recall test and determinations of brain amyloidosis (CSF amyloid-ß 42 / 40 and amyloid-PET), tau pathology (CSF and plasma phosphorylated-tau181) and neurodegeneration biomarkers (CSF and plasma neurofilament light, total-tau, fluorodeoxyglucose-PET and MRI). We used within-group locally estimated scatterplot smoothing models to compare the trajectory of biomarker changes with age in females versus males, as well as by apolipoprotein É4 carriership. Our work revealed similar prevalence, age at diagnosis and Cambridge Cognitive Examination for Older Adults with Down Syndrome scores by sex, but males showed lower modified cued recall test scores from age 45 compared with females. AT(N) biomarkers were comparable in males and females. When considering apolipoprotein É4, female É4 carriers showed a 3-year earlier age at diagnosis compared with female non-carriers (50.5 versus 53.2 years, P = 0.01). This difference was not seen in males (52.2 versus 52.5 years, P = 0.76). Our exploratory analyses considering sex, apolipoprotein É4 and biomarkers showed that female É4 carriers tended to exhibit lower CSF amyloid-ß 42/amyloid-ß 40 ratios and lower hippocampal volume compared with females without this allele, in line with the clinical difference. This work showed that biological sex did not influence clinical and biomarker profiles of Alzheimer's disease in adults with Down syndrome. Consideration of apolipoprotein É4 haplotype, particularly in females, may be important for clinical research and clinical trials that consider this population. Accounting for, reporting and publishing sex-stratified data, even when no sex differences are found, is central to helping advance precision medicine.
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The renewed interest in plant-derived drugs has led to an increased need for efficient extraction methods. The present investigation was an attempt to evaluate and compare the conventional methods of extraction with non conventional methods of extraction, such as ultrasonic-assisted extraction (UAE) and microwave-assisted extraction (MAE) methods. Pterocarpus marsupium Roxb. has been reported to contain bioactive phytochemicals, e.g., pterostilbene (3',5'-dimethoxy-4-stilbenol). The results showed that among the conventional extraction methods, percolation gave the highest yield. The non conventional methods were optimized. The extraction yield was the highest in case of MAE. The phytochemical screening of the extracts indicated similar groups of compounds in all the extracts. The thin layer chromatography showed the presence of pterostilbene in the extracts obtained by using percolation, MAE and UAE. In these extracts the quantification of pterostilbene was conducted by high performance liquid chromatography and the method was validated. The MAE method extracted significantly higher amount of pterostilbene.
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Fracionamento Químico/métodos , Pterocarpus/química , Estilbenos/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Micro-Ondas , Ultrassom/métodosRESUMO
OBJECTIVE: To describe and determine the possibility of surgical trauma to the external branch of the superior laryngeal nerve and to assess the role of intraoperative neuromonitoring in thyroid surgery. DESIGN AND SETTING: Prospective, randomized, controlled study in a teaching Hospital Universiti Sains Malaysia (HUSM), Kota Bharu, Kelantan, Malaysia. SUBJECTS: Forty two patients of both genders, whom underwent thyroid surgery divided into two groups (21 patients control group and 21 patients study group) in HUSM and were randomly selected for our study. METHODS: The use of nerve monitoring and proper surgical technique of upper thyroid pole dissection followed by its lateralization and exposure of cricothyroid space were performed in each subject in study group in order to preserve EBSLN after its identification. In control group upper thyroid vessels were ligated close to the upper thyroid pole without any effort of EBSLN identification. RESULTS: Total of 42 (35 females and 7 males) patients who underwent thyroid surgery in a period of 2 years. Evaluation of all subjects 1 case in control group presented with symptoms of EBSLN injury. CONCLUSION: Intraoperative identification and neuromonitoring can avoid injury to the EBSLN and prevent its sequential changes in voice especially for those who professionally depend to their voice.
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Traumatismos do Nervo Laríngeo/complicações , Monitorização Intraoperatória , Complicações Pós-Operatórias/etiologia , Glândula Tireoide/cirurgia , Distúrbios da Voz/etiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Traumatismos do Nervo Laríngeo/prevenção & controle , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
We review the reasons for the greater male predominance in the diagnosis of autism spectrum disorder in the non-intellectual disabled population and compare it to autism diagnosed in intellectually disabled individuals. Accurate and timely diagnosis is important, as it reduces health inequalities. Females often present later for the diagnosis. The differences are in core features, such as in social reciprocal interaction through 'camouflaging' and restricted repetitive behaviours, that are less noticeable in females and are potentially explained by the biological differences (female protective effect theory) and/or differences in presentation between the two sexes (female autism phenotype theory). Females more often present with internalising co-occurring conditions than males. We review these theories, highlighting the key differences and the impact of a diagnosis on females. We review methods to potentially improve diagnosis in females along with current and future management strategies.
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Transtorno do Espectro Autista , Transtorno Autístico , Deficiência Intelectual , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/terapia , Feminino , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , MasculinoRESUMO
Introduction: The Down syndrome population has a high prevalence for dementia, often showing their first clinical symptoms in their 40s. Methods: In a longitudinal cohort, we investigate whether amyloid deposition at time point 1 (TP1) could predict cortical thickness change at time point 2 (TP2). The association between tau burden and cortical thickness was also examined at time point 3 (TP3). Results: Between TP1 and TP2 there was pronounced cortical thinning in temporo-parietal cortices and cortical thickening in the frontal cortex. Baseline amyloid burden was strongly associated to cortical thinning progression, especially in the temporo-parietal regions. At TP3, tau deposition negatively correlated with cortical atrophy in regions where tau usually accumulates at later Braak stages. Discussion: A higher amount of amyloid accumulation triggers a cascade of changes of disease-causing processes that eventually lead to dementia. As expected, we found that regions where tau usually accumulates were those also displaying high levels of cortical atrophy.
RESUMO
This study investigates whether tau has (i) an independent effect from amyloid-ß on changes in cognitive and functional performance and (ii) a synergistic relationship with amyloid-ß in the exacerbation of decline in aging Down syndrome (DS). 105 participants with DS underwent baseline PET [18F]-AV1451 and PET [11C]PiB scans to quantify tau deposition in Braak regions II-VI and the Striatum and amyloid-ß status respectively. Linear Mixed Effects models were implemented to assess how tau and amyloid-ß deposition are related to change over three time points. Tau was a significant independent predictor of cognitive and functional change. The three-way interaction between time, [11C]PiB status and tau was significant in the models of episodic memory and visuospatial cognition. Baseline tau is a significant predictor of cognitive and functional decline, over and above the effect of amyloid-ß status. Results suggest a synergistic relationship between amyloid-ß status and tau as predictors of change in memory and visuospatial cognition.