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1.
Immunity ; 54(4): 648-659.e8, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33667383

RESUMO

Loss of lymphocytes, particularly T cell apoptosis, is a central pathological event after severe tissue injury that is associated with increased susceptibility for life-threatening infections. The precise immunological mechanisms leading to T cell death after acute injury are largely unknown. Here, we identified a monocyte-T cell interaction driving bystander cell death of T cells in ischemic stroke and burn injury. Specifically, we found that stroke induced a FasL-expressing monocyte population, which led to extrinsic T cell apoptosis. This phenomenon was driven by AIM2 inflammasome-dependent interleukin-1ß (IL-1ß) secretion after sensing cell-free DNA. Pharmacological inhibition of this pathway improved T cell survival and reduced post-stroke bacterial infections. As such, this study describes inflammasome-dependent monocyte activation as a previously unstudied cause of T cell death after injury and challenges the current paradigms of post-injury lymphopenia.


Assuntos
Coinfecção/imunologia , Proteínas de Ligação a DNA/imunologia , Tolerância Imunológica/imunologia , Inflamassomos/imunologia , Transdução de Sinais/imunologia , Animais , Apoptose/imunologia , Infecções Bacterianas/imunologia , Queimaduras/imunologia , Queimaduras/microbiologia , Coinfecção/microbiologia , Humanos , Interleucina-1beta/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Acidente Vascular Cerebral/imunologia , Acidente Vascular Cerebral/microbiologia , Linfócitos T/imunologia
2.
BMC Public Health ; 23(1): 493, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918863

RESUMO

BACKGROUND: Due to the COVID-19 pandemic, many challenges in adolescent health have been exacerbated including increased cases of early marriages, domestic violence, higher rates of anxiety and depression, and reduced access to sexual and reproductive health services for adolescents. This study examines the impacts of the pandemic on adolescent health services utilization and potential adaptations in the Philippines. METHODS: The data used in this study was from a rapid telephone assessment survey of 148 adolescent-friendly health facilities (rural health units) in the Philippines. We employed a mixed-methods research approach comprising both quantitative and qualitative analyses in three phases. First, we conducted a descriptive analysis of the status of adolescent healthcare access and utilization during COVID-19. Next, we examined using multivariate ordered logistic regressions how staff availability and adolescent health (AH) service provision modalities influenced AH service utilization in terms of the average number of adolescents served per week during compared to before the pandemic. We also conducted a complementing qualitative analysis of the challenges and corresponding adaptive solutions to ensuring continuity of AH services in facilities. RESULTS: We find that two months into the pandemic, 79% of adolescent-friendly trained staff were reporting for duty and 64% of facilities reported no staff disruptions. However, only 13% of facilities were serving the same number of adolescents or greater than before COVID-19. The use of more modalities for AH service provision (including telehealth) by facilities was significantly associated with increased likelihood to report serving the same number of adolescent or greater than before COVID-19 compared to those who used only one modality. CONCLUSION: Investments in multiple modalities of care provision, such as telehealth could improve AH services utilization and help sustain connection with adolescents during shocks, including future outbreaks or other stressors that limit physical access to health facilities.


Assuntos
Serviços de Saúde do Adolescente , COVID-19 , Adolescente , Humanos , COVID-19/epidemiologia , Pandemias , Filipinas/epidemiologia , Acessibilidade aos Serviços de Saúde
3.
Int J Health Plann Manage ; 38(6): 1629-1643, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37486971

RESUMO

We conducted qualitative research with family planning clients, potential clients, and service providers on barriers and opportunities for improving the quality of family planning services in the Philippines. The family planning service providers included the primary, secondary, and tertiary levels of the health system. Our goal was to aid in developing more effective family planning quality improvement (QI) programs. Our methods included focus groups, key informant interviews and thematic content analysis of the qualitative data. We found four themes: the components of quality of family planning care; factors influencing quality; challenges for improving quality; and provider bias in the types of family planning services offered to clients. We identified five implications for QI, including: reduce provider bias; level off the understanding of QI concepts and roles among the different family planning service providers; involve men more actively; design new digital communication strategies for reaching clients and potential clients; and explore collaborations with private sector pharmacies. The findings from this study can guide the development of a pilot family planning QI programme in the Philippines. The findings provide themes and practical insights for an intervention-focused theory of change on how to improve current programs, design new programs, be more responsive to the needs and concerns of clients and potential clients and be well-accepted and sustained by providers. This can lay the groundwork for improving family planning outcomes and reducing teenage pregnancy rates and the unmet need for family planning throughout the Philippines.


Assuntos
Serviços de Planejamento Familiar , Setor Privado , Masculino , Gravidez , Feminino , Adolescente , Humanos , Filipinas
4.
Early Child Educ J ; : 1-15, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37360593

RESUMO

The impact of COVID-19, both in quality and quantity, on the field of early childhood education, ECE is immeasurable. However, as research shows, its impact on family child care (FCC), has been worse than other sectors of ECE. FCC providers worldwide have always perceived their work as a service to families and children, yet FCC homes have not received much attention and recognition from researchers and policymakers compared to center-based ECE programs. This phenomenological inquiry with 20 FCC providers in a large urban county in California highlights the financial challenges that FCC providers faced during the early part of the pandemic before they received financial support from the state in the spring of 2021. The cost of running the program was quite high because of reduced enrollment and the regular purchase of sanitary materials. To keep their programs afloat, some participants had to lay off their staff, others kept them without salary, others had to exhaust their savings, and most incurred credit card debt. Most of them also experienced psychosocial stress. Their financial hardships during the pandemic would have been far worse without the emergency funding received from the state. However, as experts warn, the field of ECE needs a permanent solution and the situation could be even worse after the emergency funds run out in 2024. The nation has witnessed the dedicated service of FCC providers during the pandemic, especially to families of essential workers. Much work is needed at empirical and policy levels to support and celebrate the service of FCC providers.

5.
Educ Inf Technol (Dordr) ; : 1-30, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36789365

RESUMO

This paper applies Information and Communication Technologies (ICT) as well as data analysis to gain a better understanding of the existing perception on the education system. 45,278 tweets were downloaded and processed. Using a lexicon-based approach, examining the most frequently used words, and estimating similarities between terms, we detected that a predominantly negative perception of the education system exists in most of the analysed countries. A positive perception is identified in certain low-income nations. Men exhibit a more positive sentiment than women as well as a higher subjectivity in some countries. The countries that exhibit the most positive perceptions India, Canada, Pakistan, Australia, South Africa and Kenya are also those that manifest the highest subjectivity.

6.
Sensors (Basel) ; 22(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35161907

RESUMO

The morphological analysis of patterns in dried droplets has allowed the generation of efficient techniques for the detection of molecules of medical interest. However, the effectiveness of this method to reveal the coexistence of macromolecules of the same species, but different conformational states, is still unknown. To address this problem, we present an experimental study on pattern formation in dried droplets of bovine serum albumin (BSA), in folded and unfolded conformational states, in saline solution (NaCl). Folded proteins produce a well-defined coffee ring and crystal patterns all over the dry droplet. Depending on the NaCl concentration, the crystals can be small, large, elongated, entangled, or dense. Optical microscopy reveals that the relative concentration of unfolded proteins determines the morphological characteristics of deposits. At a low relative concentration of unfolded proteins (above 2%), small amorphous aggregates emerge in the deposits, while at high concentrations (above 16%), the "eye-like pattern", a large aggregate surrounded by a uniform coating, is produced. The radial intensity profile, the mean pixel intensity, and the entropy make it possible to characterize the patterns in dried droplets. We prove that it is possible to achieve 100% accuracy in identifying 4% of unfolded BSA contained in a protein solution.


Assuntos
Soroalbumina Bovina , Cloreto de Sódio
7.
J Neurochem ; 153(1): 10-32, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31630412

RESUMO

Perception of our environment entirely depends on the close interaction between the central and peripheral nervous system. In order to communicate each other, both systems must develop in parallel and in coordination. During development, axonal projections from the CNS as well as the PNS must extend over large distances to reach their appropriate target cells. To do so, they read and follow a series of axon guidance molecules. Interestingly, while these molecules play critical roles in guiding developing axons, they have also been shown to be critical in other major neurodevelopmental processes, such as the migration of cortical progenitors. Currently, a major hurdle for brain repair after injury or neurodegeneration is the absence of axonal regeneration in the mammalian CNS. By contrasts, PNS axons can regenerate. Many hypotheses have been put forward to explain this paradox but recent studies suggest that hacking neurodevelopmental mechanisms may be the key to promote CNS regeneration. Here we provide a seminar report written by trainees attending the second Flagship school held in Alpbach, Austria in September 2018 organized by the International Society for Neurochemistry (ISN) together with the Journal of Neurochemistry (JCN). This advanced school has brought together leaders in the fields of neurodevelopment and regeneration in order to discuss major keystones and future challenges in these respective fields.


Assuntos
Orientação de Axônios/fisiologia , Axônios/fisiologia , Encéfalo/ultraestrutura , Animais , Axônios/ultraestrutura , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Humanos , Regeneração Nervosa , Quiasma Óptico/crescimento & desenvolvimento , Sistema Nervoso Periférico/crescimento & desenvolvimento , Sistema Nervoso Periférico/fisiologia , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/fisiologia , Medula Espinal/ultraestrutura
8.
J Nurs Care Qual ; 35(1): 20-26, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30889084

RESUMO

BACKGROUND: Hospitalized medical-surgical patients are at risk for adverse health outcomes due to immobility. Despite well-documented consequences, low mobility is prevalent. LOCAL PROBLEM: In a 547-bed hospital, medical-surgical patients were mobilized less frequently than expected. Physical therapists were inappropriately consulted 22% of the time for routine mobility of patients. A preimplementation survey of registered nurses indicated a lack of knowledge and confidence to safely mobilize patients. METHODS: This quality improvement project implemented a nurse-led mobility program in an effort to increase early mobilization, reduce physical therapy referrals for routine mobility, and reduce the sequelae of immobility. INTERVENTIONS: The Bedside Mobility Assessment Tool and standardized interventions were implemented on 5 medical-surgical units. RESULTS: Postimplementation, nurse-led patient mobilizations increased by 40%, inappropriate physical therapy orders decreased 14%, and no significant change in patient falls or pressure injuries was noted. CONCLUSION: A nurse-led mobility program was effective in increasing safe, early mobilization of patients and improving the culture of mobility.


Assuntos
Deambulação Precoce/enfermagem , Enfermagem Médico-Cirúrgica/métodos , Idoso , Idoso de 80 Anos ou mais , California , Deambulação Precoce/tendências , Feminino , Humanos , Masculino , Enfermagem Médico-Cirúrgica/tendências , Pessoa de Meia-Idade , Desenvolvimento de Programas/métodos , Avaliação de Programas e Projetos de Saúde/métodos , Melhoria de Qualidade , Inquéritos e Questionários
9.
Stroke ; 50(9): 2513-2521, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31327315

RESUMO

Background and Purpose- Epigenetics play a significant role in brain pathologies. We currently evaluated the role of a recently discovered brain-enriched epigenetic modification known as 5-hydroxymethylcytosine (5hmC) in regulating transcriptomic and pathogenic mechanisms after focal ischemic injury. Methods- Young and aged male and female mice were subjected to transient middle cerebral artery occlusion, and the peri-infarct region was analyzed at various times of reperfusion. Two days before middle cerebral artery occlusion, short-interfering RNA against an isoform of the 5hmC producing enzyme TET (ten-eleven translocase) was injected intracerebrally. Ascorbate was injected intraperitoneally at 5 minutes, 30 minutes, or 2 hours of reperfusion. Motor function was tested with rotarod and beam-walk test. Results- Focal ischemia rapidly induced the activity of TET, the enzyme that catalyzes the formation of 5hmC and preferentially increased expression of the TET3 isoform in the peri-infarct region of the ischemic cortex. Levels of 5hmC were increased in a TET3-dependent manner, and inhibition of TET3 led to wide-scale reductions in the postischemic expression of neuroprotective genes involved in antioxidant defense and DNA repair. TET3 knockdown in adult male and female mice further increased brain degeneration after focal ischemia, demonstrating a role for TET3 and 5hmC in endogenous protection against stroke. Ascorbate treatment after focal ischemia enhanced TET3 activity and 5hmC enrichment in the peri-infarct region. TET3 activation by ascorbate provided robust protection against ischemic injury in young and aged mice of both sexes. Moreover, ascorbate treatment improved motor function recovery in both male and female mice. Conclusions- Collectively, these results indicate the potential of TET3 and 5hmC as novel stroke therapeutic targets. Visual Overview- An online visual overview is available for this article.


Assuntos
5-Metilcitosina/análogos & derivados , Encéfalo/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Acidente Vascular Cerebral/metabolismo , 5-Metilcitosina/metabolismo , Fatores Etários , Animais , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética , Infarto da Artéria Cerebral Média/genética , Masculino , Camundongos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Acidente Vascular Cerebral/genética
10.
Mol Biol Rep ; 46(5): 5511-5516, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31154603

RESUMO

MicroRNAs (miRNAs) are emerging as novel molecular tools for diagnosing and treating diseases. Rhesus monkeys (Macaca mulatta) are the most widely used nonhuman primate species for biomedical studies, yet only 912 mature miRNAs have been identified in this species compared to 2654 in humans and 1978 in mice. The aim of this project was to help bridge that gap in knowledge by evaluating circulating miRNA in naïve rhesus monkeys and comparing results with currently available databases in different species in order to identify novel, mature miRNAs. Total RNA was isolated from whole blood of ten healthy, adult rhesus macaques. After performing next generation sequencing (NGS), 475 novel, mature miRNAs were identified in rhesus macaques for the first time; of those, 423 were identified for the first time in any species. The most abundantly expressed novel rhesus macaque miRNA, hsa-miR-744-5p, has previously been described in humans. Database assessment of hsa-miR-744-5p potential gene targets showed that while the gene targets showed > 90% sequence similarity between rhesus and humans, many did not share the same consensus sequences. The identification of 475 novel miRNAs in the blood of rhesus macaque reflects the complexity and variety of miRNAs across species. Further NGS studies are needed to reveal novel miRNA that will inform on species-, tissue-, and condition-specific miRNAs.


Assuntos
Macaca mulatta/genética , MicroRNAs/genética , MicroRNAs/isolamento & purificação , Animais , Ácidos Nucleicos Livres/análise , Ácidos Nucleicos Livres/genética , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos
11.
Am J Physiol Endocrinol Metab ; 315(5): E735-E744, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30016152

RESUMO

Newborns with intrauterine growth-restriction are at increased risk of mortality and life-long comorbidities. Insulin-like growth factor-II (IGF2) deficiency in humans, as well as in mice, leads to intrauterine growth restriction and decreased neonatal glycogen stores. The present study aims to further characterize the metabolic and transcriptional consequences of Igf2 deficiency in the newborn. We found that, despite being born significantly smaller than their wild-type ( Igf2+/+) littermates, brain size was preserved in Igf2 knockout ( Igf2-/-), consistent with nutritional deficiency. Histological and triglyceride analyses of newborn livers revealed that Igf2-/- mice are born with hepatic steatosis. Gene expression analysis in Igf2-/- newborn livers showed an alteration of genes known to be dysregulated in chronic caloric restriction, including the most upregulated gene, serine dehydratase. Multiple genes connected with lipid metabolism and/or hepatic steatosis were also upregulated. Ingenuity Pathway Analysis confirmed that the biological functions most altered in livers of Igf2-/- newborns are related to lipid metabolism, with the top upstream regulator predicted to be the peroxisome proliferator-activated receptor alpha, a master regulator of hepatic lipid and carbohydrate homeostasis. Together, our data indicate that Igf2 deficiency leads to a newborn phenotype strongly reminiscent of nutritional deficiency, including growth retardation, increased brain/body weight ratio, hepatic steatosis, and characteristic changes in hepatic gene expression. We propose that in addition to its growth factor proliferating functions, Igf2 may also regulate growth by altering the expression of genes that control nutrient metabolism in the newborn.


Assuntos
Fígado Gorduroso/metabolismo , Expressão Gênica/genética , Homeostase/genética , Fator de Crescimento Insulin-Like II/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Animais , Animais Recém-Nascidos , Fígado Gorduroso/genética , Perfilação da Expressão Gênica , Fator de Crescimento Insulin-Like II/genética , Camundongos , Camundongos Knockout , Fenótipo
12.
Nat Methods ; 12(8): 725-31, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26121405

RESUMO

Antibodies are used in multiple cell biology applications, but there are no standardized methods to assess antibody quality-an absence that risks data integrity and reproducibility. We describe a mass spectrometry-based standard operating procedure for scoring immunoprecipitation antibody quality. We quantified the abundance of all the proteins in immunoprecipitates of 1,124 new recombinant antibodies for 152 chromatin-related human proteins by comparing normalized spectral abundance factors from the target antigen with those of all other proteins. We validated the performance of the standard operating procedure in blinded studies in five independent laboratories. Antibodies for which the target antigen or a member of its known protein complex was the most abundant protein were classified as 'IP gold standard'. This method generates quantitative outputs that can be stored and archived in public databases, and it represents a step toward a platform for community benchmarking of antibody quality.


Assuntos
Anticorpos Monoclonais/química , Especificidade de Anticorpos , Cromatina/química , Imunoprecipitação/métodos , Proteômica/métodos , Clonagem Molecular , Biologia Computacional/métodos , Escherichia coli/metabolismo , Células HEK293 , Humanos , Fragmentos de Imunoglobulinas/química , Imunoglobulina G/química , Espectrometria de Massas/métodos , Biblioteca de Peptídeos , Proteínas/química , Proteoma , Reprodutibilidade dos Testes
13.
Demography ; 55(4): 1583, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29498022

RESUMO

Ruggles, S., Genadek, K., Goeken, R., Grover, J., & and Sobek, M. (2017). Integrated Public Use Microdata Series: Version 7.0 [Data set]. Minneapolis: University of Minnesota. https://doi.org/10.18128/D010.V7.0.

14.
Demography ; 54(6): 2223-2247, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29101682

RESUMO

The 2000s have witnessed an expansion of interior immigration enforcement in the United States. At the same time, the country has experienced a major demographic transformation, with the number of U.S. citizens living in mixed-status households-that is, households where at least one family member is an unauthorized migrant-reaching 16 million. U.S. citizens living in mixed-status households are personally connected to the struggles experienced by their unauthorized family members. For them, immigration policy is likely to shape their current and future voting behavior. Using data from the 2002-2014 Current Population Survey Voting and Registration Supplements, we examine whether intensified immigration enforcement has affected the political engagement of U.S. citizens living in mixed-status households. We find that immigration enforcement has chilled their electoral participation by lowering their propensity to register by 5 %; however, it has not visibly affected their voting propensity among those registered. Importantly, their lower voting registration likelihood does not seem to reflect indifference for community and public matters, given that it has been accompanied by greater involvement in civic forms of political participation, such as volunteering. Understanding how immigration policy affects the political participation of a fast-growing segment of the electorate is imperative because they will inevitably constitute a rapidly rising political force in future elections.


Assuntos
Emigração e Imigração , Características da Família , Política , Política Pública , Adulto , Idoso , Demografia , Emigração e Imigração/legislação & jurisprudência , Feminino , Hispânico ou Latino , Humanos , Masculino , Pessoa de Meia-Idade , Política Pública/economia , Análise de Regressão , Inquéritos e Questionários , Migrantes , Imigrantes Indocumentados/legislação & jurisprudência , Estados Unidos , Adulto Jovem
15.
PLoS Genet ; 10(7): e1004508, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25078964

RESUMO

The phenotypic effect of some single nucleotide polymorphisms (SNPs) depends on their parental origin. We present a novel approach to detect parent-of-origin effects (POEs) in genome-wide genotype data of unrelated individuals. The method exploits increased phenotypic variance in the heterozygous genotype group relative to the homozygous groups. We applied the method to >56,000 unrelated individuals to search for POEs influencing body mass index (BMI). Six lead SNPs were carried forward for replication in five family-based studies (of ∼4,000 trios). Two SNPs replicated: the paternal rs2471083-C allele (located near the imprinted KCNK9 gene) and the paternal rs3091869-T allele (located near the SLC2A10 gene) increased BMI equally (beta = 0.11 (SD), P<0.0027) compared to the respective maternal alleles. Real-time PCR experiments of lymphoblastoid cell lines from the CEPH families showed that expression of both genes was dependent on parental origin of the SNPs alleles (P<0.01). Our scheme opens new opportunities to exploit GWAS data of unrelated individuals to identify POEs and demonstrates that they play an important role in adult obesity.


Assuntos
Proteínas Facilitadoras de Transporte de Glucose/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Canais de Potássio de Domínios Poros em Tandem/genética , Adulto , Índice de Massa Corporal , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Impressão Genômica , Genótipo , Humanos , Masculino , Obesidade/patologia , População Branca/genética
16.
Methods ; 81: 66-73, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25770357

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key regulator of circulating low density lipoprotein cholesterol (LDL-C) levels. Besides its full-length mature form, multiple variants of PCSK9 have been reported such as forms that are truncated, mutated and/or with posttranslational modifications (PTMs). Previous studies have demonstrated that most of these variants affect PCSK9's function and thereby LDL-C levels. Commercial ELISA kits are available for quantification of PCSK9, but do not allow discrimination between the various forms and PTMs of the protein. To address this issue and given the complexity and wide dynamic range of the plasma proteome, we have developed a mass spectrometric immunoassay coupled to selected reaction monitoring (MSIA-SRM) for the multiplexed quantification of several forms of circulating PCSK9 in human plasma. Our MSIA-SRM assay quantifies peptides spanning the various protein domains and the S688 phosphorylation site. The assay was applied in two distinct cohorts of obese patients and healthy pregnant women stratified by their circulating LDL-C levels. Seven PCSK9 peptides were monitored in plasma samples: one in the prodomain prior to the autocleavage site at Q152, one in the catalytic domain prior to the furin cleavage site at R218, two in the catalytic domain following R218, one in the cysteine and histidine rich domain (CHRD) and the C-terminal peptide phosphorylated at S688 and unmodified. The latter was not detectable in sufficient amounts to be quantified in human plasma. All peptides were measured with high reproducibility and with LLOQ and LOD below the clinical range. The abundance of 5 of the 6 detectable PCSK9 peptides was higher in obese patients stratified with high circulating LDL-C levels as compared to those with low LDL-C (p < 0.05). The same 5 peptides showed good and statistically significant correlations with LDL-C levels (0.55 < r < 0.65; 0.0002 ⩽ p ⩽ 0.002), but not the S688 phosphorylated peptide. However, this phosphopeptide was significantly correlated with insulin resistance (r = 0.48; p = 0.04). In the pregnant women cohort, none of the peptides were associated to LDL-C levels. However, the 6 detectable PCSK9 peptides, but not PCSK9 measured by ELISA, were significantly correlated with serum triglyceride levels in this cohort. Our results also suggest that PCSK9 circulates with S688 phosphorylated at high stoichiometry. In summary, we have developed and applied a robust and sensitive MSIA-SRM assay for the absolute quantification of all PCSK9 domains and a PTM in human plasma. This assay revealed novel relationships between PCSK9 and metabolic phenotypes, as compared to classical ELISA assays.


Assuntos
Imunoensaio/métodos , Espectrometria de Massas/métodos , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Adolescente , Adulto , Feminino , Humanos , Resistência à Insulina , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Fenótipo , Gravidez , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise , Serina Endopeptidases/metabolismo , Triglicerídeos/sangue , Adulto Jovem
17.
Clin Proteomics ; 12(1): 2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25678897

RESUMO

BACKGROUND: The anatomy of PFO suggests that it can allow thrombi and potentially harmful circulatory factors to travel directly from the venous to the arterial circulation - altering circulatory phenotype. Our previous publication using high-resolution LC-MS/MS to profile protein and peptide expression patterns in plasma showed that albumin was relatively increased in donor samples from PFO-related than other types of ischemic strokes. Since albumin binds a host of molecules and acts as a carrier for lipoproteins, small molecules and drugs, we decided to investigate the albumin-bound proteins (in a similar sample cohort) in an effort to unravel biological changes and potentially discover biomarkers related to PFO-related stroke and PFO endovascular closure. METHODS: The method used in this study combined albumin immuno-enrichment with high resolution LC-MS in order to specifically capture and quantify the albumin-bound proteins. Subsequently, we measured cholesterol and HDL in a larger, separate cohort of PFO stroke patients, pre and post closure. RESULTS: The results demonstrated that a number of proteins were specifically associated with albumin in samples with and without endovascular closure of the PFO, and that the protein profiles were very different. Eight proteins, typically associated with HDL were common to both sample sets and quantitatively differently abundant. Pathway analysis of the MS results suggested that enhanced cholesterol efflux and reduced lipid oxidation were associated with PFO closure. Measurement of total cholesterol and HDL in a larger cohort of PFO closure samples using a colorimetric assay was consistent with the proteomic predictions. CONCLUSIONS: The collective data presented in this study demonstrate that analysis of albumin-bound proteins could provide a valuable tool for biomarker discovery on the effects of PFO endovascular closure. In addition, the results suggest that PFO endovascular closure can potentially have effects on HDL, cholesterol and albumin-bound ApoA-I abundance, therefore possibly providing benefits in cardioprotective functions.

18.
Proteomics ; 14(12): 1445-56, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24668948

RESUMO

The detection and quantification of insulin and its therapeutic analogs is important for medical, sports doping, and forensic applications. Synthetic variants contain slight sequence variations to affect bioavailability. To reduce sample handling bias, a universal extraction method is required for simultaneous extraction of endogenous and variant insulins with subsequent targeted quantification by LC-MS. A mass spectrometric immunoassay (MSIA), a multiplexed assay for intact insulin and its analogues that couples immunoenrichment with high resolution and accurate mass (HR/AM) spectrometric detection across the clinical range is presented in this report. The assay is sensitive, selective, semi-automated and can potentially be applied to detect new insulin isoforms allowing their further incorporation into second or third generation assays.


Assuntos
Cromatografia Líquida/métodos , Ensaios de Triagem em Larga Escala , Imunoensaio/métodos , Insulina/análogos & derivados , Insulina/sangue , Proteômica , Espectrometria de Massas em Tandem/métodos , Humanos , Isoformas de Proteínas
19.
J Proteome Res ; 13(12): 5415-30, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25244318

RESUMO

Data-dependent acquisition (DDA) and data-independent acquisition strategies (DIA) have both resulted in improved understanding of proteomics samples. Both strategies have advantages and disadvantages that are well-published, where DDA is typically applied for deep discovery and DIA may be used to create sample records. In this paper, we present a hybrid data acquisition and processing strategy (pSMART) that combines the strengths of both techniques and provides significant benefits for qualitative and quantitative peptide analysis. The performance of pSMART is compared to published DIA strategies in an experiment that allows the objective assessment of DIA performance with respect to interrogation of previously acquired MS data. The results of this experiment demonstrate that pSMART creates fewer decoy hits than a standard DIA strategy. Moreover, we show that pSMART is more selective, sensitive, and reproducible than either standard DIA or DDA strategies alone.


Assuntos
Processamento Eletrônico de Dados/métodos , Peptídeos/análise , Proteoma/análise , Proteômica/métodos , Sequência de Aminoácidos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Peptídeos/metabolismo , Proteoma/metabolismo , Reprodutibilidade dos Testes , Software
20.
J Proteome Res ; 13(2): 1077-87, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24392642

RESUMO

Apolipoprotein E (ApoE) is a polymorphic protein that plays a major role in lipid metabolism in the central nervous system and periphery. It has three common allelic isoforms, ApoE2, ApoE3, and ApoE4, that differ in only one or two amino acids. ApoE isoforms have been associated with the occurrence and progression of several pathological conditions, such as coronary atherosclerosis and Alzheimer's disease. The aim of this study was to develop a mass spectrometry (MS)-based assay for absolute quantification of ApoE isoforms in cerebrospinal fluid and plasma samples using isotope-labeled peptides. The assay included five tryptic peptides: CLAVYQAGAR (ApoE2), LGADMEDVCGR (ApoE2 and 3), LAVYQAGAR (ApoE3 and 4), LGADMEDVR (ApoE4), and LGPLVEQGR (total ApoE). Both cerebrospinal fluid and plasma samples were assayed to validate the method. The digestion yield and the extension of chemical modifications in selected amino acid residues (methionine oxidation, glutamine deamidation, and cyclization of N-terminus carbamidomethylcysteine) were also studied. The ApoE phenotype was successfully assigned to all samples analyzed in a blinded manner. The method showed good linearity (R(2) > 0.99) and reproducibility (within laboratory imprecision <13%). The comparison of the MS-based assay with an ELISA for total ApoE concentration showed a moderate correlation (R(2) = 0.59). This MS-based assay can serve as an important tool in clinical studies aiming to elucidate the association between ApoE genotype, total ApoE, and ApoE isoform concentrations in various disorders related to ApoE polymorphisms.


Assuntos
Apolipoproteínas E/química , Peptídeos/química , Isoformas de Proteínas/química , Sequência de Aminoácidos , Apolipoproteínas E/análise , Cromatografia Líquida , Espectrometria de Massas , Dados de Sequência Molecular , Oxirredução , Isoformas de Proteínas/análise , Tripsina/química
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