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1.
PLoS One ; 18(12): e0293046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38039314

RESUMO

Human adenovirus (HAdV), particularly the HAdV type 5 (HAdV-5), has been extensively utilized in the development of vector vaccines due to its high immunogenicity, good safety profile, and ease of propagation. However, one of the main challenges in its use is the presence of pre-existing immunity among vaccine recipients. Pre-existing neutralizing antibodies (NAbs) can prevent the uptake of HAdV-5 vectors and reduce vaccine efficacy. Hence, this study investigated the seroprevalence of NAbs against HAdV-5 in urban and rural regions of the Philippines. Luciferase-based neutralization assay was performed on 391 plasma/serum samples. Out of these samples, 346 or 88.5% were positive for HAdV-5 NAbs, and the majority of them (56.8%) had high titers against the virus. Among the regions included in this study, Bicol (Region V) had the highest seroprevalence rate (94.1%). Our findings show that a significant number of adults in the Philippines have pre-existing immunity against HAdV-5. This supports the recommendation that vaccination programs in the country should consider implementing vaccination techniques, such as a prime-boost regimen or addition of booster doses, to address the potential negative effects of pre-existing HAdV-5 immunity in the efficacy of adenoviral vector-based vaccines.


Assuntos
Vacinas contra Adenovirus , Adenovírus Humanos , Adulto , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Estudos Soroepidemiológicos , Filipinas/epidemiologia
3.
Acta Neuropathol Commun ; 10(1): 49, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395816

RESUMO

X-linked dystonia-parkinsonism (XDP) is a progressive adult-onset neurodegenerative disorder caused by insertion of a SINE-VNTR-Alu (SVA) retrotransposon in the TAF1 gene. The SVA retrotransposon contains a CCCTCT hexameric repeat tract of variable length, whose length is inversely correlated with age at onset. This places XDP in a broader class of repeat expansion diseases, characterized by the instability of their causative repeat mutations. Here, we observe similar inverse correlations between CCCTCT repeat length with age at onset and age at death and no obvious correlation with disease duration. To gain insight into repeat instability in XDP we performed comprehensive quantitative analyses of somatic instability of the XDP CCCTCT repeat in blood and in seventeen brain regions from affected males. Our findings reveal repeat length-dependent and expansion-based instability of the XDP CCCTCT repeat, with greater levels of expansion in brain than in blood. The brain exhibits regional-specific patterns of instability that are broadly similar across individuals, with cerebellum exhibiting low instability and cortical regions exhibiting relatively high instability. The spectrum of somatic instability in the brain includes a high proportion of moderate repeat length changes of up to 5 repeats, as well as expansions of ~ 20- > 100 repeats and contractions of ~ 20-40 repeats at lower frequencies. Comparison with HTT CAG repeat instability in postmortem Huntington's disease brains reveals similar brain region-specific profiles, indicating common trans-acting factors that contribute to the instability of both repeats. Analyses in XDP brains of expansion of a different SVA-associated CCCTCT located in the LIPG gene, and not known to be disease-associated, reveals repeat length-dependent expansion at overall lower levels relative to the XDP CCCTCT repeat, suggesting that expansion propensity may be modified by local chromatin structure. Together, the data support a role for repeat length-dependent somatic expansion in the process(es) driving the onset of XDP and prompt further investigation into repeat dynamics and the relationship to disease.


Assuntos
Distonia , Distúrbios Distônicos , Doença de Huntington , Transtornos Parkinsonianos , Adulto , Distúrbios Distônicos/diagnóstico por imagem , Distúrbios Distônicos/genética , Doenças Genéticas Ligadas ao Cromossomo X , Humanos , Doença de Huntington/genética , Masculino , Transtornos Parkinsonianos/genética , Retroelementos
4.
Brain Commun ; 3(4): fcab253, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746789

RESUMO

X-linked dystonia-parkinsonism (XDP) is a monogenic neurodegenerative disorder of the basal ganglia, which presents as a combination of hyperkinetic movements and parkinsonian features. The underlying genetic mechanism involves the insertion of a SINE-VNTR-Alu retrotransposon within the TAF1 gene. Interestingly, alterations of TAF1 have been involved in multiple neurological diseases. In XDP, the SINE-VNTR-Alu insertion in TAF1 has been proposed to result in alternative splicing defects, including the decreased incorporation of a neuron-specific microexon annotated as 34'. This mechanism has become controversial as recent studies failed to provide support. In order to resolve this conundrum, we examined the alternative splicing patterns of TAF1 mRNAs in XDP and control brains. The impact of the disease-associated SINE-VNTR-Alu on alternative splicing of microexon 34' was further investigated in cellular assays. Subsequently, microexon 34' incorporation was explored by RT-PCR and Nanopore long-read sequencing of TAF1 mRNAs from XDP and control brains tissues. Using cell-based splicing assays, we demonstrate that presence of the disease-associated SINE-VNTR-Alu does not affect the inclusion of microexon 34'. In addition, we show that (1) microexon 34'-containing TAF1 mRNAs are detected at similar levels in XDP as in controls and that (2) the architecture of TAF1 transcripts is remarkably similar between XDP and controls brains. These results indicate that microexon 34' incorporation into TAF1 mRNA is not affected in XDP brains. Our findings shift the current paradigm of XDP by discounting alternative splicing of TAF1 microexon 34' as the molecular basis for this disease.

5.
BMC Infect Dis ; 21(1): 1170, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800996

RESUMO

BACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.


Assuntos
COVID-19 , COVID-19/terapia , Humanos , Imunização Passiva , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento , Soroterapia para COVID-19
6.
J Neural Transm (Vienna) ; 128(4): 575-587, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33439365

RESUMO

X-Linked Dystonia-Parkinsonism (XDP) is a neurodegenerative disease affecting individuals with ancestry to the island of Panay in the Philippines. In recent years there has been considerable progress at elucidating the genetic basis of XDP and candidate disease mechanisms in patient-derived cellular models, but the neural substrates that give rise to XDP in vivo are still poorly understood. Previous studies of limited XDP postmortem brain samples have reported a selective dropout of medium spiny neurons within the striatum, although neuroimaging of XDP patients has detected additional abnormalities in multiple brain regions beyond the basal ganglia. Given the need to fully define the CNS structures that are affected in this disease, we created a brain bank in Panay to serve as a tissue resource for detailed studies of XDP-related neuropathology. Here we describe this platform, from donor recruitment and consent to tissue collection, processing, and storage, that was assembled within a predominantly rural region of the Philippines with limited access to medical and laboratory facilities. Thirty-six brains from XDP individuals have been collected over an initial 4 years period. Tissue quality was assessed based on histologic staining of cortex, RNA integrity scores, detection of neuronal transcripts in situ by fluorescent hybridization chain reaction, and western blotting of neuronal and glial proteins. The results indicate that this pipeline preserves tissue integrity to an extent compatible with a range of morphologic, molecular, and biochemical analyses. Thus the algorithms that we developed for working in rural communities may serve as a guide for establishing similar brain banks for other rare diseases in indigenous populations.


Assuntos
Distonia , Distúrbios Distônicos , Doenças Neurodegenerativas , Encéfalo/diagnóstico por imagem , Distúrbios Distônicos/genética , Doenças Genéticas Ligadas ao Cromossomo X , Humanos
7.
PLoS One ; 15(12): e0243655, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33315879

RESUMO

X-linked Dystonia-Parkinsonism (XDP) is a neurodegenerative disease linked to an insertion of a SINE-VNTR-Alu (SVA)-type retrotransposon within an intron of TAF1. This SVA insertion induces aberrant TAF1 splicing and partial intron retention, thereby decreasing levels of the full-length transcript. Here we sought to determine if these altered transcriptional dynamics caused by the SVA are also accompanied by local changes in histone acetylation, given that these modifications influence gene expression. Because TAF1 protein may itself exhibit histone acetyltransferase activity, we also examined whether decreased TAF1 expression in XDP cell lines and post-mortem brain affects global levels of acetylated histone H3 (AcH3). The results demonstrate that total AcH3 are not altered in XDP post-mortem prefrontal cortex or cell lines. We also did not detect local differences in AcH3 associated with TAF1 exons or intronic sites flanking the SVA insertion. There was, however, a decrease in AcH3 association with the exon immediately proximal to the intronic SVA, and this decrease was normalized by CRISPR/Cas-excision of the SVA. Collectively, these data suggest that the SVA insertion alters histone status in this region, which may contribute to the dysregulation of TAF1 expression.


Assuntos
Distúrbios Distônicos/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Histona Acetiltransferases/genética , Histonas/metabolismo , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Acetilação , Células Cultivadas , Distúrbios Distônicos/metabolismo , Fibroblastos/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Humanos , Íntrons , Retroelementos
8.
Neurobiol Dis ; 144: 105032, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32739252

RESUMO

Neuroinflammation plays a pathogenic role in neurodegenerative diseases and recent findings suggest that it may also be involved in X-linked Dystonia-Parkinsonism (XDP) pathogenesis. Previously, fibroblasts and neuronal stem cells derived from XDP patients demonstrated hypersensitivity to TNF-α, dysregulation in NFκB signaling, and an increase in several pro-inflammatory markers. However, the role of inflammatory processes in XDP patient brain remains unknown. Here we demonstrate that there is a significant increase in astrogliosis and microgliosis in human post-mortem XDP prefrontal cortex (PFC) compared to control. Furthermore, there is a significant increase in histone H3 citrullination (H3R2R8R17cit3) with a concomitant increase in peptidylarginine deaminase 2 (PAD2) and 4 (PAD4), the enzymes catalyzing citrullination, in XDP post-mortem PFC. While there is a significant increase in myeloperoxidase (MPO) levels in XDP PFC, neutrophil elastase (NE) levels are not altered, suggesting that MPO may be released by activated microglia or reactive astrocytes in the brain. Similarly, there was an increase in H3R2R8R17cit3, PAD2 and PAD4 levels in XDP-derived fibroblasts. Importantly, treatment of fibroblasts with Cl-amidine, a pan inhibitor of PAD enzymes, reduced histone H3 citrullination and pro-inflammatory chemokine expression, without affecting cell survival. Taken together, our results demonstrate that inflammation is increased in XDP post-mortem brain and fibroblasts and unveil a new epigenetic potential therapeutic target.


Assuntos
Citrulinação , Distúrbios Distônicos/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Histonas/metabolismo , Inflamação/metabolismo , Córtex Pré-Frontal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrócitos/metabolismo , Astrócitos/patologia , Autopsia , Sobrevivência Celular , Quimiocinas/efeitos dos fármacos , Quimiocinas/metabolismo , Citrulinação/efeitos dos fármacos , Distúrbios Distônicos/patologia , Feminino , Fibroblastos/efeitos dos fármacos , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Gliose/metabolismo , Gliose/patologia , Histonas/efeitos dos fármacos , Humanos , Inflamação/patologia , Elastase de Leucócito/metabolismo , Masculino , Microglia/metabolismo , Microglia/patologia , Pessoa de Meia-Idade , Ornitina/análogos & derivados , Ornitina/farmacologia , Peroxidase/metabolismo , Córtex Pré-Frontal/patologia , Proteína-Arginina Desiminase do Tipo 2/metabolismo , Proteína-Arginina Desiminase do Tipo 4/metabolismo
9.
10.
Front Neurol ; 9: 830, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30374324

RESUMO

Objectives: X-linked dystonia parkinsonism (XDP) is a neurodegenerative movement disorder endemic to the island of Panay in the Philippines. We undertook a population-based prevalence study to enumerate all cases of XDP in Panay. We first developed a 4-item questionnaire to distinguish XDP suspects from the general population. In the present study we aimed to revalidate this questionnaire to distinguish XDP from similar conditions so as to give it greater utility in the clinical setting. Patients and Methods: A total of 306 subjects (114 cases and 192 controls) were screened in from the 16 towns and 1 city of Capiz province. Their responses to the previously developed 4-item questionnaire were collected and multivariable logistic regression was performed to develop a predictive model. The accuracy of the model was determined by using it on a subset of patients; then, a scoring system based on the model coefficients was established. Results: With a cut-off score of 6, the questionnaire had an accuracy of 70.7% (95% CI 0.57-0.82), a sensitivity of 84.6 % (95% CI 0.65-0.96) and a specificity of 59.4 % (95% CI 0.41-0.76). The item on "shuffling of feet" was the strongest predictor in distinguishing XDP from its common mimics. Conclusion: We were able to revalidate a simple, four-item questionnaire that could distinguish XDP from its common mimics with fair accuracy. The questionnaire along with other clinical features can be used to determine which patients need specialty evaluation and genetic testing to verify a diagnosis of XDP.

11.
Proc Natl Acad Sci U S A ; 114(51): E11020-E11028, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29229810

RESUMO

X-linked dystonia-parkinsonism (XDP) is a neurodegenerative disease associated with an antisense insertion of a SINE-VNTR-Alu (SVA)-type retrotransposon within an intron of TAF1 This unique insertion coincides with six additional noncoding sequence changes in TAF1, the gene that encodes TATA-binding protein-associated factor-1, which appear to be inherited together as an identical haplotype in all reported cases. Here we examined the sequence of this SVA in XDP patients (n = 140) and detected polymorphic variation in the length of a hexanucleotide repeat domain, (CCCTCT)n The number of repeats in these cases ranged from 35 to 52 and showed a highly significant inverse correlation with age at disease onset. Because other SVAs exhibit intrinsic promoter activity that depends in part on the hexameric domain, we assayed the transcriptional regulatory effects of varying hexameric lengths found in the unique XDP SVA retrotransposon using luciferase reporter constructs. When inserted sense or antisense to the luciferase reading frame, the XDP variants repressed or enhanced transcription, respectively, to an extent that appeared to vary with length of the hexamer. Further in silico analysis of this SVA sequence revealed multiple motifs predicted to form G-quadruplexes, with the greatest potential detected for the hexameric repeat domain. These data directly link sequence variation within the XDP-specific SVA sequence to phenotypic variability in clinical disease manifestation and provide insight into potential mechanisms by which this intronic retroelement may induce transcriptional interference in TAF1 expression.


Assuntos
Expansão das Repetições de DNA , Distúrbios Distônicos/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Histona Acetiltransferases/genética , Retroelementos , Elementos Nucleotídeos Curtos e Dispersos , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Ordem dos Genes , Estudos de Associação Genética , Loci Gênicos , Humanos , Masculino , Modelos Biológicos , Linhagem , Fenótipo , Regiões Promotoras Genéticas , Ativação Transcricional
12.
Mod Pathol ; 23(5): 737-42, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20081814

RESUMO

A significant proportion of ductal carcinomas in situ (DCISs) of the breast diagnosed on core biopsies had invasion upon excision. An assessment of various invasion predictors in the biopsies yielded conflicting results. A cohort of 157 cases with needle core biopsy diagnosed with DCISs (including 109 histologically proven DCISs, and 48 cases with invasion upon excision) were evaluated for the numbers of positive and total cores, the percentage of positivity, lobular cancerization, tumor nuclear grade, necrosis, calcification, predominate histological pattern, lymphocytic infiltrate and excisional tumor size. The mean positive core percentage and excisional tumor size were 76% and 2.8 cm for invasive and 66% and 1.9 cm for noninvasive groups. In the biopsy of the invasive group, cancerization of lobules was present in 52%, and nuclear grades 1, 2 and 3 were present in 31, 31 and 38%, respectively. Large comedo and small noncomedo necroses were present in 48 and 10%, whereas large and small calcifications were present in 16 and 21%. Solid, cribriform and papillary patterns were observed in 88, 38 and 21%, respectively. Moderate to marked lymphoid infiltrate was present in 31%. In the biopsy of the noninvasive group, cancerization of lobules was present in 69%, and the nuclear grades 1, 2 and 3 were present in 23, 48 and 29%, respectively. Large comedo and small noncomedo necroses were present in 35 and 11%, whereas large and small calcifications were present in 33 and 23%. Solid, cribriform and papillary patterns were observed in 85, 39 and 9%, respectively. Moderate to marked lymphoid infiltrate was present in 36%. Comparing these groups, a higher positive core percentage, papillary pattern and less cancerization of lobules in the cores and larger excisional tumor size were associated with a higher chance of invasion. Calcification, necrosis and nuclear grade were not significant invasion predictors.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Mama/patologia , Calcinose/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Pessoa de Meia-Idade , Necrose/patologia , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Valor Preditivo dos Testes
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