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1.
J Org Chem ; 89(5): 3309-3318, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38362875

RESUMO

The chemosensor literature contains many reports of fluorescence sensing using polyaromatic hydrocarbon fluorophores such as pyrene, tetraphenylethylene, or polyaryl(ethynylene), where the fluorophore is excited with ultraviolet light (<400 nm) and emits in the visible region of 400-500 nm. There is a need for general methods that convert these "turn-on" hydrocarbon fluorescent sensors into ratiometric sensing paradigms. One simple strategy is to mix the responsive hydrocarbon sensor with a second non-responsive dye that is excited by ultraviolet light but emits at a distinctly longer wavelength and thus acts as a reference signal. Five new cyanine dye cassettes were created by covalently attaching a pyrene, tetraphenylethylene, or biphenyl(ethynylene) component as the ultraviolet-absorbing energy donor directly to the pentamethine chain of a deep-red cyanine (Cy5) energy acceptor. Fluorescence emission studies showed that these Cy5-cassettes exhibited large pseudo-Stokes shifts and high through-bond energy transfer efficiencies upon excitation with ultraviolet light. Practical potential was demonstrated with two examples of ratiometric fluorescence sensing using a single ultraviolet excitation wavelength. One example mixed a Cy5-cassette with a pyrene-based fluorescent indicator that responded to changes in Cu2+ concentration, and the other example mixed a Cy5-cassette with the fluorescent pH sensing dye, pyranine.

2.
Stat Sin ; 33(Spec Issue): 1295-1318, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37483468

RESUMO

In this work, we propose a longitudinal quantile regression framework that enables a robust characterization of heterogeneous covariate-response associations in the presence of high-dimensional compositional covariates and repeated measurements of both response and covariates. We develop a globally adaptive penalization procedure, which can consistently identify covariate sparsity patterns across a continuum set of quantile levels. The proposed estimation procedure properly aggregates longitudinal observations over time, and ensures the satisfaction of the sum-zero coefficient constraint that is needed for proper interpretation of the effects of compositional covariates. We establish the oracle rate of uniform convergence and weak convergence of the resulting estimators, and further justify the proposed uniform selector of the tuning parameter in terms of achieving global model selection consistency. We derive an efficient algorithm by incorporating existing R packages to facilitate stable and fast computation. Our extensive simulation studies confirm the theoretical findings. We apply the proposed method to a longitudinal study of cystic fibrosis children where the association between gut microbiome and other diet-related biomarkers is of interest.

3.
J Org Chem ; 86(15): 10819-10828, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34254798

RESUMO

A diversity-oriented chemoenzymatic approach for the collective preparation of sulfated core 2 O-GalNAc glycans and their nonsulfated counterparts was described. A sulfated trisaccharide and a nonsulfated trisaccharide were chemically synthesized by combining flexible protected group manipulations and sequential one-pot glycosylations. The divergent enzymatic extension of these two trisaccharides, using a panel of robust glycosyltransferases that can recognize sulfated substrates and differentiating the branches with specifically designed glycosylation sequences to achieve regioselective sialylation, provided 36 structurally well-defined O-GalNAc glycans.


Assuntos
Polissacarídeos , Sulfatos , Glicosilação , Glicosiltransferases/metabolismo , Trissacarídeos
4.
Inorg Chem ; 58(11): 7303-7309, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31094520

RESUMO

TiO2 nanostructures that feature a two-dimensional (2D) morphology have attracted extensive attention in environment processing and energy conversion fields owing to their peculiarly large surface area and superior transfer efficiency of photogenerated carriers. In this work, we proposed a hybrid approach including a plasma electrolyte oxidation (PEO) and ion exchange strategy to in situ synthesize TiO2 nanosheets on a flexible Ti mesh substrate, in which the layered Na2Ti2O5 nanosheets were fabricated as a template. The TiO2 nanosheets are crystalline anatase phase and exhibit excellent photocatalytic activity and stability in removing phenol. With the modification of the Pt cocatalyst, the phenol degradation performance has been significantly enhanced. More importantly, the in situ grown TiO2 nanosheets on the flexible Ti mesh provide strong substrate adhesion that enables superior photocatalytic stability for cyclic degradation of phenol. It can be expected that the synthetic strategy proposed in this work can pave a solid way toward the in situ growth of various TiO2-based composite nanophotocatalysts with sufficient active sites and excellent photocatalytic properties, and thus, it will open up more opportunities for environment processing and energy conversion.

5.
Biometrics ; 74(3): 954-965, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29427311

RESUMO

Recurrent events data are frequently encountered in biomedical follow-up studies. The generalized accelerated recurrence time (GART) model (Sun et al., 2016), which formulates covariate effects on the time scale of the mean function of recurrent events (i.e., time to expected frequency), has arisen as a useful secondary analysis tool to provide meaningful physical interpretations. In this article, we investigate the GART model in a multivariate recurrent events setting, where subjects may experience multiple types of recurrent events and some event types may be missing. We propose methods for the GART model that utilize the inverse probability weighting technique or the estimating equation projection strategy to handle event types that are missing at random. The new methods do not require imposing any parametric model for the missing mechanism, and thus are robust; moreover, they enjoy easy and stable implementation. We establish the uniform consistency and weak convergence of the resulting estimators and develop appropriate inferential procedures. Extensive simulation studies and an application to a dataset from Cystic Fibrosis Foundation Patient Registry (CFFPR) illustrate the validity and practical utility of the proposed methods.


Assuntos
Modelos Estatísticos , Recidiva , Simulação por Computador , Fibrose Cística/patologia , Interpretação Estatística de Dados , Seguimentos , Humanos , Análise Multivariada , Fatores de Tempo
6.
BMC Med Res Methodol ; 16(1): 122, 2016 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-27639560

RESUMO

BACKGROUND: Persistent Pseudomonas aeruginosa (PPA) infection promotes lung function deterioration in children with cystic fibrosis (CF). Although early CF diagnosis through newborn screening (NBS) has been shown to provide nutritional/growth benefit, it is unclear whether NBS lowers the risk of PPA infection and how the effect of NBS vary with age. Modeling the onset age of PPA infection is challenging because 1) the onset age of PPA infection is interval censored in patient registry data; and 2) some risk factors such as NBS may have time-varying effects. METHODS: This problem fits into the framework of a recently developed Bayesian dynamic Cox model for interval censored data, where each regression coefficient is allowed to be time-varying to an extent determined by the data. RESULTS: Application of the methodology to data from the CF Foundation Patient Registry revealed interesting findings. Compared with patients with meconium ileus or diagnosed through signs or symptoms, patients diagnosed through NBS had significantly lower risks of acquiring PPA infection between age 1 and 2 years, and the benefit in survival rate was found to last up to age 4 years. Two cohorts of five years apart were compared. Patients born in cohort 2003-2004 had significantly lower risks of the PPA infections at any age up to 4 years than those born in 1998-1999. CONCLUSIONS: The study supports benefits of NBS on PPA infection in early childhood. In addition, our analyses demonstrate that patients in the more recent cohort had significantly lower risks of acquiring PPA infection up to age 4 years, which suggests improved CF treatment and care over time.


Assuntos
Fibrose Cística/mortalidade , Infecções por Pseudomonas/mortalidade , Pseudomonas aeruginosa , Algoritmos , Pré-Escolar , Fibrose Cística/diagnóstico , Fibrose Cística/microbiologia , Diagnóstico Precoce , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Cadeias de Markov , Método de Monte Carlo , Triagem Neonatal , Modelos de Riscos Proporcionais , Infecções por Pseudomonas/microbiologia , Risco
7.
Biom J ; 58(3): 635-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26547058

RESUMO

We develop time-varying association analyses for onset ages of two lung infections to address the statistical challenges in utilizing registry data where onset ages are left-truncated by ages of entry and competing-risk censored by deaths. Two types of association estimators are proposed based on conditional cause-specific hazard function and cumulative incidence function that are adapted from unconditional quantities to handle left truncation. Asymptotic properties of the estimators are established by using the empirical process techniques. Our simulation study shows that the estimators perform well with moderate sample sizes. We apply our methods to the Cystic Fibrosis Foundation Registry data to study the relationship between onset ages of Pseudomonas aeruginosa and Staphylococcus aureus infections.


Assuntos
Biometria/métodos , Modelos Estatísticos , Idade de Início , Simulação por Computador , Fibrose Cística/complicações , Interpretação Estatística de Dados , Humanos , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/epidemiologia , Risco , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/epidemiologia , Estatísticas não Paramétricas
8.
J Pediatr ; 167(5): 1089-95, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26298625

RESUMO

OBJECTIVE: To examine differences between use of World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) growth reference in children with cystic fibrosis (CF) up to 2 years of age. STUDY DESIGN: Growth from 1-24 months in 2587 children, born 2003-2006 and recorded in the US CF Foundation Registry, was evaluated using WHO and CDC references. RESULTS: In both boys and girls with CF aged 1-24 months, use of WHO charts resulted in ∼8 percentile lower length-for-age and ∼13% higher short stature rate (length-for-age <5th percentile). WHO weight-for-age was ∼9 percentile lower prior to age 6 months, crossed at 6-7 months, and remained ∼14 percentile higher at 8-24 months. WHO weight-for-length (WFL) percentile (WFLp) was similar before 12 months but ∼10 percentile higher at 12-24 months compared with CDC. When using WHO charts, 9% of children had underweight (WFLp <50th) classified differently and this rate varied with age: 4% in the first year, 7% at 12, 13% at 15, and 16% at 18 months, respectively. Weight status assessed by WHO body mass index (BMI) charts was different from WHO WFL charts. At 24 months when switching back to CDC, 26% of children with normal WFLp on WHO charts appeared underweight on CDC charts. A 70th percentile of WHO BMI percentile was equivalent to the 50th percentile CDC BMI percentile. CONCLUSIONS: Growth status in children with CF differed when using WHO and CDC references, particularly during the second year of life. These differences need to be considered for all uses of growth assessment in CF.


Assuntos
Centers for Disease Control and Prevention, U.S./estatística & dados numéricos , Fibrose Cística/fisiopatologia , Gráficos de Crescimento , Sistema de Registros , Organização Mundial da Saúde , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência , Estudos Retrospectivos , Estados Unidos
9.
WMJ ; 114(4): 143-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26436182

RESUMO

BACKGROUND: Alcohol consumption is common on college campuses and is associated with negative consequences. Factors associated with availability of alcohol are not completely understood. OBJECTIVE: To describe how proximity and density of alcohol outlets are associated with any drinking and binge drinking in students at the University of Wisconsin-Madison. METHODS: Participants were full-time students enrolled in the Young Adults Eating and Active for Health, a multisite, randomized intervention that assessed a variety of health behaviors. Geographic information systems were used to calculate proximity and enumerate alcohol outlet densities. Participants were categorized as "drinkers" or "nondrinkers" based on self-reported alcohol consumption. Binge drinking was categorized as "non-binge drinker," "frequent binge drinker," and "excessive binge drinker." Analysis included regression, t tests, and chi-square tests. RESULTS. Among the 166 participants, 126 (76%) were drinkers. Among drinkers, 80 (63%) were either frequent or excessive binge drinkers. Drinkers lived closer to an alcohol outlet than non-drinkers (0.18 +/- 0.15 vs. 0.61 +/- 1.59 miles, respectively, P=0.005). Within a 1-mile walking radius, there were 47% more establishments for drinkers (153 +/- 47 compared to 104 +/- 55 outlets for nondrinkers, P<0.0001). At distances of 0.10-0.25 and 0.25-0.50 miles, twice as many outlets were available to drinkers (19 +/- 19 and 43 +/- 25, respectively) compared to nondrinkers (7 +/- 11 and 20 +/- 22, respectively), P<0.001. Proximity and density were hot associated with binge drinking frequency. CONCLUSION: Drinkers lived closer to alcohol outlets and had significantly more outlets available at a distance of up to 1 mile. Municipal and college administrators could consider limiting alcohol license distributions in municipalities with high alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Bebidas Alcoólicas/provisão & distribuição , Comércio/estatística & dados numéricos , Características de Residência , Estudantes/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Feminino , Humanos , Masculino , Obesidade/prevenção & controle , Fatores de Risco , Inquéritos e Questionários , Viagem , Universidades , Wisconsin/epidemiologia
10.
Chem Sci ; 15(10): 3633-3639, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455008

RESUMO

Fluorescent molecular probes that report nitroreductase activity have promise as imaging tools to elucidate the biology of hypoxic cells and report the past hypoxic history of biomedical tissue. This study describes the synthesis and validation of a "first-in-class" ratiometric, hydrophilic near-infrared fluorescent molecular probe for imaging hypoxia-induced nitroreductase activity in 2D cell culture monolayers and 3D multicellular tumor spheroids. The probe's molecular structure is charge-balanced and the change in ratiometric signal is based on Förster Resonance Energy Transfer (FRET) from a deep-red, pentamethine cyanine donor dye (Cy5, emits ∼660 nm) to a linked near-infrared, heptamethine cyanine acceptor dye (Cy7, emits ∼780 nm). Enzymatic reduction of a 4-nitrobenzyl group on the Cy7 component induces a large increase in Cy7/Cy5 fluorescence ratio. The deep penetration of near-infrared light enables 3D optical sectioning of intact tumor spheroids, and visualization of individual hypoxic cells (i.e., cells with raised Cy7/Cy5 ratio) as a new way to study tumor spheroids. Beyond preclinical imaging, the near-infrared fluorescent molecular probe has high potential for ratiometric imaging of hypoxic tissue in living subjects.

11.
Nat Chem ; 16(6): 881-892, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38844638

RESUMO

Ganglioside glycans are ubiquitous and complex biomolecules that are involved in a wide range of biological functions and disease processes. Variations in sialylation and sulfation render the structural complexity and diversity of ganglioside glycans, and influence protein-carbohydrate interactions. Structural and functional insights into the biological roles of these glycans are impeded due to the limited accessibility of well-defined structures. Here we report an integrated chemoenzymatic strategy for expeditious and systematic synthesis of a comprehensive 65-membered ganglioside glycan library covering all possible patterns of sulfation and sialylation. This strategy relies on the streamlined modular assembly of three common sialylated precursors by highly stereoselective iterative sialylation, modular site-specific sulfation through flexible orthogonal protecting-group manipulations and enzymatic-catalysed diversification using three sialyltransferase modules and a galactosidase module. These diverse ganglioside glycans enable exploration into their structure-function relationships using high-throughput glycan microarray technology, which reveals that different patterns of sulfation and sialylation on these glycans mediate their unique binding specificities.


Assuntos
Gangliosídeos , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/metabolismo , Gangliosídeos/química , Gangliosídeos/metabolismo , Sialiltransferases/metabolismo , Sialiltransferases/química , Sulfatos/química , Sulfatos/metabolismo , Glicômica/métodos
12.
J Pediatr ; 163(2): 376-82, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23535012

RESUMO

OBJECTIVES: To test the hypothesis that pubertal peak height velocity (PHV) in cystic fibrosis (CF) has improved and is influenced by prepubertal growth and genetic potential. STUDY DESIGN: PHV from 1862 children born in 1984-87 and documented in the 1986-2008 US CF Foundation Registry was determined by statistical modeling and classified into normal, delayed (2-SD > average age), attenuated (magnitude <5th percentile), or both delayed and attenuated (D&A). Genetic potential for height was estimated by parental stature. RESULTS: PHV averaged 8.4 cm/year at age 14.0 years in boys and 7.0 cm/year at age 12.1 years in girls, ∼6-month delay and ∼15% reduction compared with healthy children. PHV was normal in 60%, delayed in 9%, attenuated in 21%, and D&A in 5%. Patients with delayed PHV reached similar adult height percentile (boys: 34th, girls: 46th) to those with normal PHV (boys: 33rd, girls: 34th); both were significantly taller than the attenuated (boys: 11th, girls: 19th) and D&A PHV subgroups (boys: 8th, girls: 14th). Pancreatic-sufficient patients had taller prepubertal and adult heights but similar PHV compared with pancreatic-insufficient or meconium ileus patients. Adjusting for genetic potential reduced adult height percentiles more in boys (from 25th to 16th) than girls (from 28th to 24th). Height at age 7 years, PHV age and magnitude, and parental stature significantly predicted adult height. CONCLUSIONS: Pubertal PHV has improved in children with CF born after mid-1980s compared with older cohorts but remains below normal. Suboptimal prepubertal and pubertal growth led to adult height below genetic potential in CF.


Assuntos
Estatura , Fibrose Cística/fisiopatologia , Adolescente , Fatores Etários , Estatura/genética , Criança , Fibrose Cística/genética , Feminino , Humanos , Masculino , Puberdade , Fatores de Tempo , Adulto Jovem
13.
Respir Care ; 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596652

RESUMO

BACKGROUND: Spinal muscular atrophy (SMA) is a neurodegenerative disease that results in progressive muscular atrophy and weakness. The primary cause of morbidity and mortality in these children is pulmonary disease due to poor airway clearance that leads to acute respiratory failure. There is a paucity of literature on the treatment of children with SMA and acute respiratory failure. METHODS: We performed a retrospective chart review of pediatric patients with SMA type I or II admitted to the PICU in a tertiary-care children's hospital with acute respiratory failure who required mechanical ventilation and/or aggressive airway clearance. RESULTS: The study included 300 unique encounters among 137 unique subjects. All the subjects received airway clearance at home before admission, and 257 encounters (85.7%) were supported with noninvasive ventilation (NIV) before admission. Sixty-eight subjects (49.6%) required endotracheal intubation on admission or at some point during their PICU stay. The median (interquartile range [IQR]) time to intubation was 0 (0-20) h, and the median (IQR) duration of mechanical ventilation was 2 (1-5) d on invasive mechanical ventilation with no statistical difference between type I and type II (P = .89). Of those, 65 (91.1%) were successfully extubated to NIV on the first attempt, whereas 4 subjects (5.8%) required multiple extubation attempts and 3 subjects (4.4%) required subsequent tracheostomy. For the subjects who were intubated, both PICU and hospital length of stay were longer (P < .001) when compared with the subjects managed by NIV alone. The subjects with SMA type I had a longer PICU length of stay, with a median (IQR) of 5 (3-11) d versus 4 (2-7) d (P = .002). The hospital length of stay and duration of invasive mechanical ventilation were not statistically different (P = .055 and P = .068, respectively). CONCLUSIONS: The subjects with SMA types I or II can be treated successfully with NIV and aggressive airway clearance during acute respiratory failure. Similarly, when intubation is required, successful extubation can be achieved with NIV transitional support combined with aggressive airway clearance maneuvers.

14.
JAMA Pediatr ; 177(4): 401-409, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780186

RESUMO

Importance: The prevalence of obesity among youths 2 to 19 years of age in the US from 2017 to 2018 was 19.3%; previous studies suggested that school lunch consumption was associated with increased obesity. The Healthy, Hunger-Free Kids Act of 2010 (HHFKA) strengthened nutritional standards of school-based meals. Objective: To evaluate the association between the HHFKA and youth body mass index (BMI). Design, Setting, and Participants: This cohort study was conducted using data from the Environmental Influences on Child Health Outcomes program, a nationwide consortium of child cohort studies, between January 2005 and March 2020. Cohorts in the US of youths aged 5 to 18 years with reported height and weight measurements were included. Exposures: Full implementation of the HHFKA. Main Outcomes and Measures: The main outcome was annual BMI z-score (BMIz) trends before (January 2005 to August 2016) and after (September 2016 to March 2020) implementation of the HHFKA, adjusted for self-reported race, ethnicity, maternal education, and cohort group. An interrupted time-series analysis design was used to fit generalized estimating equation regression models. Results: A total of 14 121 school-aged youths (7237 [51.3%] male; mean [SD] age at first measurement, 8.8 [3.6] years) contributing 26 205 BMI measurements were included in the study. Overall, a significant decrease was observed in the annual BMIz in the period following implementation of the HHFKA compared with prior to implementation (-0.041; 95% CI, -0.066 to -0.016). In interaction models to evaluate subgroup associations, similar trends were observed among youths 12 to 18 years of age (-0.045; 95% CI, -0.071 to -0.018) and among youths living in households with a lower annual income (-0.038; 95% CI, -0.063 to -0.013). Conclusions and Relevance: In this cohort study, HHFKA implementation was associated with a significant decrease in BMIz among school-aged youths in the US. The findings suggest that school meal programs represent a key opportunity for interventions to combat the childhood obesity epidemic given the high rates of program participation and the proportion of total calories consumed through school-based meals.


Assuntos
Obesidade Infantil , Humanos , Masculino , Criança , Adolescente , Pré-Escolar , Adulto Jovem , Adulto , Feminino , Índice de Massa Corporal , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Estudos de Coortes , Política Nutricional , Instituições Acadêmicas
15.
Photochem Photobiol ; 98(2): 303-310, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34592003

RESUMO

Polymethine fluorophores have facilitated the advance of biological and material sciences, due to their advantageous photophysical properties. However, the need to maintain a monomeric state can severely limit the utility and processability of dyes. High concentrations of fluorophore can lead to aggregation and negate the beneficial photophysical properties of monomers. Another concern is "crossing the cyanine limit" in which delocalization within the polymethine scaffold is broken, producing the presence of an asymmetric state diminishing its photophysical behavior. Herein, we attempt to overcome these limitations by exploring anion exchange on a cationic flavylium heptamethine scaffold. By increasing the size and hydrophobicity of the anion, we can effectively tune the degree of ion pairing within the polymethine dye. Interestingly, we found that the effect of ion pairing on photophysical properties was subtle for the flavylium heptamethine scaffold in comparison to the more commonly used indolenine cyanine dye. Utilizing larger weakly coordinating anions enabled solubility of the flavylium heptamethine fluorophore in nonpolar solvents, which could otherwise not be achieved. Even with more subtle effects than classic cyanine dyes, anion exchange on flavylium polymethine dyes holds potential for further manipulation of the properties of these low energy dyes.


Assuntos
Corantes Fluorescentes , Ânions , Carbocianinas , Solubilidade , Solventes
16.
Front Cell Infect Microbiol ; 12: 1060748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36733852

RESUMO

Rhinovirus causes many types of respiratory illnesses, ranging from minor colds to exacerbations of asthma. Moraxella catarrhalis is an opportunistic pathogen that is increased in abundance during rhinovirus illnesses and asthma exacerbations and is associated with increased severity of illness through mechanisms that are ill-defined. We used a co-infection model of human airway epithelium differentiated at the air-liquid interface to test the hypothesis that rhinovirus infection promotes M. catarrhalis adhesion and survival on the respiratory epithelium. Initial experiments showed that infection with M. catarrhalis alone did not damage the epithelium or induce cytokine production, but increased trans-epithelial electrical resistance, indicative of increased barrier function. In a co-infection model, infection with the more virulent rhinovirus-A and rhinovirus-C, but not the less virulent rhinovirus-B types, increased cell-associated M. catarrhalis. Immunofluorescent staining demonstrated that M. catarrhalis adhered to rhinovirus-infected ciliated epithelial cells and infected cells being extruded from the epithelium. Rhinovirus induced pronounced changes in gene expression and secretion of inflammatory cytokines. In contrast, M. catarrhalis caused minimal effects and did not enhance RV-induced responses. Our results indicate that rhinovirus-A or C infection increases M. catarrhalis survival and cell association while M. catarrhalis infection alone does not cause cytopathology or epithelial inflammation. Our findings suggest that rhinovirus and M. catarrhalis co-infection could promote epithelial damage and more severe illness by amplifying leukocyte inflammatory responses at the epithelial surface.


Assuntos
Asma , Coinfecção , Infecções por Enterovirus , Humanos , Moraxella catarrhalis , Rhinovirus , Coinfecção/complicações , Mucosa Respiratória , Asma/complicações , Células Epiteliais/metabolismo
17.
J Allergy Clin Immunol ; 126(6): 1157-62, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21051081

RESUMO

BACKGROUND: Obesity has been proposed to be a risk factor for the development of childhood asthma. OBJECTIVE: We sought to examine weight status from birth to age 5 years in relation to the occurrence of asthma at ages 6 and 8 years. METHODS: Two hundred eighty-five full-term high-risk newborns with at least 1 asthmatic/atopic parent enrolled in the Childhood Origin of Asthma project were studied from birth to age 8 years. Overweight was defined by weight-for-length percentiles of greater than the 85th percentile before the age of 2 years and a body mass index percentile of greater than the 85th percentile at ages 2 to 5 years. RESULTS: No significant concurrent association was found between overweight status and wheezing/asthma occurrence at each year of age. In contrast, longitudinal analyses revealed complex relationships between being overweight and asthma. Being overweight at age 1 year was associated with a decreased risk of asthma at age 6 (odds ratio [OR], 0.32; P = .02) and 8 (OR, 0.35; P = .04) years, as well as better lung function. However, being overweight beyond infancy was not associated with asthma occurrence. In fact, only children who were overweight at age 5 years but not at age 1 year had an increased risk of asthma at age 6 years (OR, 5.78; P = .05). CONCLUSION: In children genetically at high risk of asthma, being overweight at age 1 year was associated with a decreased risk of asthma and better lung function at ages 6 and 8 years. However, being overweight beyond infancy did not have any protective effect and even could confer a higher risk for asthma.


Assuntos
Asma/diagnóstico , Asma/epidemiologia , Filho de Pais com Deficiência , Obesidade/diagnóstico , Obesidade/epidemiologia , Asma/fisiopatologia , Índice de Massa Corporal , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Obesidade/fisiopatologia , Prevalência , Sons Respiratórios , Fatores de Risco
18.
Org Lett ; 23(15): 6090-6093, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34296882

RESUMO

An efficient and simple approach for stereoselective synthesis of ß-Kdo C-glycosides was described, which relies on easily available peracetylated anomeric acetate or anomeric 2-pyridyl sulfide to couple with carbonyl compounds via SmI2-mediated Reformatsky reactions. The utility of this methodology is exemplified by the streamlined synthesis of a practical ß-Kdo C-glycoside with an anomeric aminopropyl linker to conjugate with other biomolecules for further biological studies.


Assuntos
Glicosídeos/síntese química , Iodetos/química , Samário/química , Açúcares Ácidos/síntese química , Glicosídeos/química , Estrutura Molecular , Estereoisomerismo , Açúcares Ácidos/química
19.
Ann Appl Stat ; 14(2): 956-976, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34079614

RESUMO

Recurrent events are commonly encountered in longitudinal studies. The observation of recurrent events is often stopped by a dependent terminal event in practice. For this data scenario, we propose two sensible adaptations of the generalized accelerated recurrence time (GART) model (Sun et al., 2016) to provide useful alternative analyses that can offer physical interpretations while rendering extra flexibility beyond the existing work based on the accelerated failure time model. Our modeling strategies align with the rationale underlying the use of the survivors' rate function or the adjusted rate function to account for the presence of the dependent terminal event. For the proposed models, we identify and develop estimation and inference procedures, which can be readily implemented based on existing software. We establish the asymptotic properties of the new estimator. Simulation studies demonstrate good finite-sample performance of the proposed methods. An application to a dataset from the Cystic Fibrosis Foundation Patient Registry (CFFPR) illustrates the practical utility of the new methods.

20.
Exp Biol Med (Maywood) ; 234(5): 542-52, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19234056

RESUMO

For obese individuals seeking to optimize health and well-being, healthy dietary strategies are important. Vegetables and fruits contribute to a healthy diet, and increased consumption may cause weight reduction by displacing foods high in energy and fat. The objective of this study was to determine if advising high vegetable (8 servings) and moderate fruit (2-3 servings) consumption would result in weight reduction in obese individuals. We compared this to advising a more traditional strategy of reducing daily energy intake by 500 kcal (2.1 MJ)/d and limiting energy from fat to

Assuntos
Dieta , Ingestão de Energia , Verduras , Redução de Peso , Adulto , Glicemia/análise , Gorduras na Dieta/administração & dosagem , Jejum/sangue , Feminino , Frutas , Hematócrito , Humanos , Insulina/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Proteína C/análise , Fatores de Tempo
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