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1.
Adv Pediatr ; 69(1): 75-93, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35985718

RESUMO

Rhinosinusitis in children, as in adults, can be classified by duration (acute, recurrent, and chronic) and by cause (viral, bacterial, and inflammatory) and needs to be treated accordingly after careful investigation which include through clinical history, laboratory tests, and, if necessary, nasal endoscopy and imaging studies.


Assuntos
Rinite , Sinusite , Adulto , Criança , Doença Crônica , Humanos , Rinite/diagnóstico , Rinite/terapia , Sinusite/diagnóstico , Sinusite/terapia
2.
Allergy Rhinol (Providence) ; 11: 2152656719900338, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030313

RESUMO

BACKGROUND: Inadequate titers of pneumococcal antibody (PA) are commonly present among patients with recurrent respiratory infections. OBJECTIVE: We sought to determine the effect of the degree of inadequacy in baseline PA titers on the subsequent polysaccharide vaccine response, the incidence of sinusitis, and allergic conditions. METHODS: A total of 313 patients aged 6 to 70 years with symptoms of recurrent respiratory infections were classified by baseline-pPA (percentage of protective [≥1.3 µg/mL] PA serotypes/total tested serotypes) and postvaccination pPA (post-pPA): Group A (adequate baseline-pPA), Group B (inadequate baseline-pPA, adequate post-pPA, responders), and Group C (inadequate baseline-pPA, inadequate postpPA, nonresponders, specific antibody deficiency [SAD]). Immunity against Streptococcus pneumoniae was defined as adequate when the pPA was ≥70%. Each group and combined groups, Group AB (inadequate baseline-pPA), and Group BC (adequate post-pPA) were analyzed for demographics, history of sinusitis, recurrent sinusitis in the following year, allergic conditions, and association with inadequate individual serotype titers. RESULTS: Over 80% of patients with respiratory symptoms had inadequate baseline-pPA. Baseline-pPA and SAD prevalence are inversely related (odds ratio = 2.02, 95% CI: 1.15-3.57, P = .01). Inadequate serotype 3 antibody titer is highly associated with SAD (odds ratio = 2.02, 96% CI: 1.61-5.45, P < .01). The groups with inadequate pPA (Group B and C, or BC) had significantly higher percentage of patients with chronic rhinosinusitis (P < .001), allergic sensitization, and allergic rhinitis (P < .05). Group A contained higher percentage of patients with recurrent upper airway infections (P < .001). CONCLUSION: Low baseline-pPA and low antibody titers to serotype 3 are highly associated with SAD, increased incidence of respiratory infections including CRS and allergic conditions.

3.
Allergy Rhinol (Providence) ; 11: 2152656720980408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33403153

RESUMO

BACKGROUND: Specific antibody deficiency (SAD) is highly associated with chronic rhinosinusitis (CRS) and is defined by inadequate post-vaccination percentage of protective (≥1.3 ug/mL) pneumococcal antibody serotypes divided by total tested serotypes (post-pPA). OBJECTIVE: Although < 70% post-pPA has been used commonly as the criterion for SAD, we sought to evaluate the clinical outcome of a different definition of SAD. METHODS: 203 patients aged 6 to 70 years with CRS were classified, retrospectively by pre-vaccination pPA (pre-pPA) and post-pPA by two different criteria. Using 70% as the threshold for adequate pneumococcal antibody (PA) response, patients were classified as: Group A (adequate pre-pPA), Group B (inadequate pre-pPA, adequate post-pPA), Group C (inadequate pre-pPA, inadequate post-pPA, SAD). Using 50% as the threshold, patients were similarly classified as: Group A', B' and C'. RESULTS: The recurrence rate of sinusitis during the next one year in Group A (pre-pPA ≥70%) was significantly less than that of Group A' (pre-pPA ≥50%) (10% vs. 34%, P = .03). Group A had lower incidence of sinusitis than Group B (pre-pPA < 70%, post-pPA ≥70%) (10% vs. 34%, P = .025). Among Group B' patients, the recurrence rate of sinusitis was significantly less among those with post-pPA of ≥70% than those with 50%-69% (28% vs. 69%, P < .01). CONCLUSION: Employment of a 70% pPA threshold for SAD in comparison to a 50% threshold would decrease the incidence of sinusitis in the next one year by vaccinating patients in 51-69% pPA range. Pre-existing PAs (Group A) yielded a higher protection against sinusitis than vaccine-acquired antibodies (Group B).

4.
Allergy Rhinol (Providence) ; 10: 2152656718821281, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30671281

RESUMO

BACKGROUND: Chronic cough in children is a diagnostic challenge. OBJECTIVE: To discover the utility of nasal dipsticks and polymerase chain reaction (PCR)-DNA analysis in differentiating bacterial sinusitis from other causes of chronic cough and identifying pathogens from the nasal cavity. METHOD: We recruited 22 patients under 15 years of age with cough lasting longer than 4 weeks (group 1), 7 controls with allergic rhinitis (group 2), and 10 controls without respiratory symptoms (group 3). Based on symptoms, the results of nasal secretion assays, and nasal endoscopy, a diagnosis of clinical bacterial sinusitis was made. We identified potential pathogens by quantitative PCR of nasal secretions. RESULTS: Group 1A (cough with clinical bacterial sinusitis n = 10): Eight (80%) patients had bacterial sinusitis associated with dominant potential pathogenic bacteria (PPB): Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Group 1B (cough without clinical bacterial sinusitis n = 12): None had dominant PPB. Group 2 (allergic rhinitis n = 7): None had dominant PPB. Group 3 (asymptomatic n = 10): None had dominant PPB. Twenty to 57% of all groups were colonized with Staphylococcus aureus. Fifty to 70% were colonized with Staphylococcus epidermidis, Corynebacterium pseudodiphtheriticum, and Dolosigranulum pigrum. CONCLUSION: In children with chronic cough, clinicians can utilize a simple and inexpensive nasal secretion dipstick assay for rapid diagnosis of sinusitis and identify PPB by DNA-PCR test for specific antibiotic treatment.

5.
Proc Natl Acad Sci U S A ; 112(26): 7897-902, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26080437

RESUMO

In diverse classes of organic optoelectronic devices, controlling charge injection, extraction, and blocking across organic semiconductor-inorganic electrode interfaces is crucial for enhancing quantum efficiency and output voltage. To this end, the strategy of inserting engineered interfacial layers (IFLs) between electrical contacts and organic semiconductors has significantly advanced organic light-emitting diode and organic thin film transistor performance. For organic photovoltaic (OPV) devices, an electronically flexible IFL design strategy to incrementally tune energy level matching between the inorganic electrode system and the organic photoactive components without varying the surface chemistry would permit OPV cells to adapt to ever-changing generations of photoactive materials. Here we report the implementation of chemically/environmentally robust, low-temperature solution-processed amorphous transparent semiconducting oxide alloys, In-Ga-O and Ga-Zn-Sn-O, as IFLs for inverted OPVs. Continuous variation of the IFL compositions tunes the conduction band minima over a broad range, affording optimized OPV power conversion efficiencies for multiple classes of organic active layer materials and establishing clear correlations between IFL/photoactive layer energetics and device performance.

6.
J Am Chem Soc ; 136(51): 17762-73, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25420044

RESUMO

To achieve densely packed charge-selective organosilane-based interfacial layers (IFLs) on the tin-doped indium oxide (ITO) anodes of organic photovoltaic (OPV) cells, a series of Ar2N-(CH2)n-SiCl3 precursors with Ar = 3,4-difluorophenyl, n = 3, 6, 10, and 18, was synthesized, characterized, and chemisorbed on OPV anodes to serve as IFLs. To minimize lateral nonbonded -NAr2···Ar2N- repulsions which likely limit IFL packing densities in the resulting self-assembled monolayers (SAMs), precursor mixtures having both small and large n values are simultaneously deposited. These "heterogeneous" SAMs are characterized by a battery of techniques: contact angle measurements, X-ray reflectivity, X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy (UPS), cyclic voltammetry, and DFT computation. It is found that the headgroup densities of these "supersaturated" heterogeneous SAMs (SHSAMs) are enhanced by as much as 17% versus their homogeneous counterparts. Supersaturation significantly modifies the IFL properties including the work function (as much as 16%) and areal dipole moment (as much as 49%). Bulk-heterojunction OPV devices are fabricated with these SHSAMs: ITO/IFL/poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][2-[[(2-ethylhexyl)oxy]carbonyl]-3-fluorothieno[3,4-b]thiophenediyl]]:phenyl-C71-butyric acid methyl ester (PTB7:PC71BM)/LiF/Al. OPVs having SHSAM IFLs exhibit significantly enhanced performance (PCE by 54%; Voc by 35%) due to enhanced charge selectivity and collection, with the PCE rivaling or exceeding that of PEDOT:PSS IFL devices -7.62%. The mechanism underlying the enhanced performance involves modified hole collection and selectivity efficiency inferred from the UPS data. The ITO/SAM/SHSAM surface potential imposed by the dipolar SAMs causes band bending and favorably alters the Schottky barrier height. Thus, interfacial charge selectivity and collection are enhanced as evident in the greater OPV Voc.

7.
ACS Appl Mater Interfaces ; 6(21): 19347-54, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25329000

RESUMO

The ionization potentials (IPs) and electron affinities (EAs) of widely used conjugated polymers are evaluated by cyclic voltammetry (CV) in conventional electrochemical and lithium-ion battery media, and also by ultraviolet photoelectron spectroscopy (UPS) in vacuo. By comparing the data obtained in the different systems, it is found that the IPs of the conjugated polymer films determined by conventional CV (IPC) can be correlated with UPS-measured HOMO energy levels (EH,UPS) by the relationship EH,UPS = (1.14 ± 0.23) × qIPC + (4.62 ± 0.10) eV, where q is the electron charge. It is also found that the EAs of the conjugated polymer films measured via CV in conventional (EAC) and Li(+) battery (EAB) media can be linearly correlated by the relationship EAB = (1.07 ± 0.13) × EAC + (2.84 ± 0.22) V. The slopes and intercepts of these equations can be correlated with the dielectric constants of the polymer film environments and the redox potentials of the reference electrodes, as modified by the surrounding electrolyte, respectively.

8.
Adv Mater ; 26(42): 7170-7, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25205206

RESUMO

A solution-processed electrochemical charge-trap flash memory element is based on a solid solution of copper and zirconium oxides (Cu-ZrO2) as a charge-trapping layer. Because of the facile reduction of Cu(2+) to Cu(1+), Cu-ZrO2 thin films are especially effective in memory devices based on thin-film transistors when the devices are fabricated from combustion-processed metal-oxide semiconductors (In2O3 and an indium-gallium oxide).

9.
ACS Appl Mater Interfaces ; 5(18): 9224-40, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23942417

RESUMO

With the goal of investigating and enhancing anode performance in bulk-heterojunction (BHJ) organic photovoltaic (OPV) cells, the glass/tin-doped indium oxide (ITO) anodes are modified with a series of robust silane-tethered bis(fluoroaryl)amines to form self-assembled interfacial layers (IFLs). The modified ITO anodes are characterized by contact angle measurements, X-ray reflectivity, ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, grazing incidence X-ray diffraction, atomic force microscopy, and cyclic voltammetry. These techniques reveal the presence of hydrophobic amorphous monolayers of 6.68 to 9.76 Å thickness, and modified anode work functions ranging from 4.66 to 5.27 eV. Two series of glass/ITO/IFL/active layer/LiF/Al BHJ OPVs are fabricated with the active layer = poly(3-hexylthiophene):phenyl-C71-butyric acid methyl ester (P3HT:PC71BM) or poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)-carbonyl]thi-eno[3,4-b]thiophenediyl]]:phenyl-C71-butyric acid methyl ester (PTB7:PC71BM). OPV analysis under AM 1.5G conditions reveals significant performance enhancement versus unmodified glass/ITO anodes. Strong positive correlations between the electrochemically derived heterogeneous electron transport rate constants (ks) and the device open circuit voltage (Voc), short circuit current (Jsc), hence OPV power conversion efficiency (PCE), are observed for these modified anodes. Furthermore, the strong functional dependence of the device response on ks increases as greater densities of charge carriers are generated in the BHJ OPV active layer, and is attributable to enhanced anode carrier extraction in the case of high-ks IFLs.


Assuntos
Energia Solar , Aminas/química , Eletrodos , Fulerenos/química , Vidro/química , Interações Hidrofóbicas e Hidrofílicas , Silanos/química , Tiofenos/química , Compostos de Estanho/química
10.
Chem Commun (Camb) ; 46(31): 5686-8, 2010 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-20567748

RESUMO

Substitution of a pyridyl for the hydroxyphenyl moiety in the Green Fluorescent Protein analog p-hydroxybenzylidene-dimethylimidiazolinone produces a chromophore which "turns on" fluorescence in the presence of Zn(2+) or Cd(2+) ions. Such a phenomenon provides "proof of principle" for using GFP chromophores in a variety of sensing applications.


Assuntos
Compostos de Benzil/química , Complexos de Coordenação/química , Imidazolinas/química , Cádmio/química , Complexos de Coordenação/síntese química , Proteínas de Fluorescência Verde/química , Ligantes , Conformação Molecular , Espectrometria de Fluorescência , Zinco/química
11.
Blood ; 108(12): 3769-76, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16896156

RESUMO

Our previous results demonstrated that B cells from a patient (pt1) with non-X-linked hyper-IgM syndrome (HIGM) possess an atypical CD23(lo) phenotype that is unaffected by CD40-mediated activation. To investigate the molecular mechanism underlying defective CD23 expression in pt1 B cells, we used lymphoblastoid cell lines that express LMP1 under the control of a tetracycline-inducible promoter (LCL(tet)). Our analysis revealed that the CD23(lo) phenotype in the pt1-LCL(tet) cells is a direct consequence of diminished CD23 transcription. We demonstrate a marked decrease in c-Rel-containing complexes that bind to the proximal CD23a/b promoters in pt1-LCL(tet) extracts, resulting from an overall lower expression of c-Rel in pt1-LCL(tet) cells. Analysis of c-Rel mRNA revealed relatively equal amounts in pt1-LCL(tet) and control LCL(tet) cells, indicating that diminished c-Rel protein expression is unrelated to decreased transcription. Finally, a critical role for c-Rel in CD23 regulation was demonstrated by effectively altering c-Rel expression that resulted in the direct modulation of CD23 surface expression. Collectively, these findings demonstrate that low levels of c-Rel are the underlying cause of aberrant CD23 expression in pt1 B cells and are likely to play a critical role in the pathophysiology of this form of HIGM.


Assuntos
Linfócitos B/metabolismo , Regulação da Expressão Gênica , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/metabolismo , Proteínas Proto-Oncogênicas c-rel/biossíntese , Receptores de IgE/biossíntese , Linfócitos B/patologia , Linhagem Celular Transformada , Humanos , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/genética , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/patologia , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/fisiopatologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-rel/genética , Receptores de IgE/genética , Síndrome , Transcrição Gênica
12.
J Leukoc Biol ; 78(3): 620-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15961576

RESUMO

Our previous investigation of a patient (pt1) with non-X-linked hyper-immunoglobulin M syndrome revealed a CD40-mediated defect in B cell activation that resulted in low CD23 expression and absence of germ-line transcription and class-switch recombination. These deficiencies were complemented in vitro by a high threshold of sustained signaling through CD40. To further analyze the signaling defect in pt1 B cells, two types of Epstein-Barr virus lymphoblastoid cell lines (LCLs) were generated that either constitutively expressed the viral transforming protein latent membrane protein-1 (LMP1; pt1-LCL) or expressed it under the control of a tet-inducible promoter (pt1-LCL(tet)). Because LMP1 signals through the CD40 pathway, the pt1-LCL and pt1-LCL(tet) lines allow comparison of downstream functions in response to either constitutive LMP1 signals or regulated LMP1 and CD40 signals. Immortalized pt1-LCLs were initially CD23(lo)/CD38(hi) and reverted to a CD23(hi)/CD38(lo) phenotype upon extended growth in culture, suggesting that the CD40 defect was reversed by selection and/or constitutive expression of LMP1. In contrast, pt1-LCL(tet) cells retained the CD23(lo)/CD38(hi) phenotype after extended periods of culture and failed to up-regulate CD23 in response to CD40 signals. Analysis of pt1-LCL(tet) cells in response to the CD40 signals in the presence or absence of LMP1 revealed that mitogenic activation resulted only from LMP1 and not CD40, indicating a difference in the response of pt1 B cells to these two distinct signals. Together, these data demonstrate that the pt1-LCL(tet) cells maintain the CD40-related defect and provide a unique approach to study the independent effects of LMP1- and CD40-directed signals.


Assuntos
Linfócitos B/imunologia , Antígenos CD40/imunologia , Imunoglobulina M/imunologia , Síndromes de Imunodeficiência/imunologia , Proteínas da Matriz Viral/imunologia , ADP-Ribosil Ciclase 1/biossíntese , ADP-Ribosil Ciclase 1/genética , Linfócitos B/virologia , Linhagem Celular Transformada , Humanos , Imunoglobulina M/biossíntese , Fenótipo , Receptores de IgE/biossíntese , Receptores de IgE/genética , Transdução de Sinais/imunologia , Proteínas da Matriz Viral/genética
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