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1.
Magn Reson Chem ; 62(3): 190-197, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38237932

RESUMO

Since 1993, it has been known that 13 C chemical shift tensor (i.e., δ11 , δ22 , and δ33 ) provides information sufficient to distinguish between COOH and COO- sites. Herein, four previously unreported metrics are proposed for differentiating COOH/COO- moieties. A new relationship is also introduced that correlates the asymmetry (i.e., δ11 -δ22 ) of COOH sites to the proximity of hydrogen bond donating partners within 2.6 Å with high accuracy (±0.05 Å). Conversely, a limitation to all proposed metrics is that they fail to distinguish between COO- and hydrogen disordered COOH sites. To reconcile this omission, a new approach is proposed based on T1 measurements of both 1 H and 13 C. The 13 C T1 values are particularly sensitive with the T1 for hydrogen disordered COOH moieties found to be nearly six times smaller than T1 's from COO- sites.

2.
Int J Mol Sci ; 25(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39063147

RESUMO

Primary cell culture is a powerful model system to address fundamental questions about organismal physiology at the cellular level, especially for species that are difficult, or impossible, to study under natural or semi-natural conditions. Due to their ease of use, primary fibroblast cultures are the dominant model system, but studies using both somatic and germ cells are also common. Using these models, genome evolution and phylogenetic relationships, the molecular and biochemical basis of differential longevities among species, and the physiological consequences of life history evolution have been studied in depth. With the advent of new technologies such as gene editing and the generation of induced pluripotent stem cells (iPSC), the field of molecular evolutionary physiology will continue to expand using both descriptive and experimental approaches.


Assuntos
Evolução Molecular , Cultura Primária de Células , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , Filogenia , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/fisiologia
3.
J Am Chem Soc ; 145(8): 4589-4600, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795004

RESUMO

Metal-organic frameworks (MOFs) that display photoredox activity are attractive materials for sustainable photocatalysis. The ability to tune both their pore sizes and electronic structures based solely on the choice of the building blocks makes them amenable for systematic studies based on physical organic and reticular chemistry principles with high degrees of synthetic control. Here, we present a library of eleven isoreticular and multivariate (MTV) photoredox-active MOFs, UCFMOF-n, and UCFMTV-n-x% with a formula Ti6O9[links]3, where the links are linear oligo-p-arylene dicarboxylates with n number of p-arylene rings and x mol% of multivariate links containing electron-donating groups (EDGs). The average and local structures of UCFMOFs were elucidated from advanced powder X-ray diffraction (XRD) and total scattering tools, consisting of parallel arrangements of one-dimensional (1D) [Ti6O9(CO2)6]∞ nanowires connected through the oligo-arylene links with the topology of the edge-2-transitive rod-packed hex net. Preparation of an MTV library of UCFMOFs with varying link sizes and amine EDG functionalization enabled us to study both their steric (pore size) and electronic (highest occupied molecular orbital-lowest unoccupied molecular orbital, HOMO-LUMO, gap) effects on the substrate adsorption and photoredox transformation of benzyl alcohol. The observed relationship between the substrate uptake and reaction kinetics with the molecular traits of the links indicates that longer links, as well as increased EDG functionalization, exhibit impressive photocatalytic rates, outperforming MIL-125 by almost 20-fold. Our studies relating photocatalytic activity with pore size and electronic functionalization demonstrate how these are important parameters to consider when designing new MOF photocatalysts.

4.
Am J Physiol Regul Integr Comp Physiol ; 325(1): R45-R54, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37184223

RESUMO

With the advent of tissue culture, and eventually the in vitro growth and maintenance of individual cell types, it became possible to ask mechanistic questions about whole organism physiology that are impractical to address within a captive setting or within the whole organism. The earliest studies focused on understanding the wound-healing response while refining cell growth and maintenance protocols from various species. In addition to its extensive use in biomedical research, this approach has been co-opted by comparative physiologists interested in reductionist/mechanistic questions related to how cellular physiology can help explain whole organism function. Here, we provide a historical perspective on the emergence of primary cell culture with an emphasis on fibroblasts followed by an overview of applying this method to ask questions about the role of life-history evolution in shaping organismal physiology at the cellular level, as well as the effect of exogenous factors (i.e., temperature, and oxygen availability) on cellular function. Finally, we propose future uses for primary fibroblasts to address questions in conservation biology and comparative physiology.


Assuntos
Fibroblastos , Fisiologia Comparada , Células Cultivadas , Proliferação de Células , Fibroblastos/metabolismo , Cicatrização
5.
Eur Radiol ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37943312

RESUMO

OBJECTIVES: To quantify brain microstructural changes in recently diagnosed relapsing-remitting multiple sclerosis (RRMS) using longitudinal T1 measures, and determine their associations with clinical disability. METHODS: Seventy-nine people with recently diagnosed (< 6 months) RRMS were recruited from a single-centre cohort sub-study, and underwent baseline and 1-year brain MRI, including variable flip angle T1 mapping. Median T1 was measured in white matter lesions (WML), normal-appearing white matter (NAWM), cortical/deep grey matter (GM), thalami, basal ganglia and medial temporal regions. Prolonged T1 (≥ 2.00 s) and supramedian T1 (relative to cohort WML values) WML voxel counts were also measured. Longitudinal change was assessed with paired t-tests and compared with Bland-Altman limits of agreement from healthy control test-retest data. Regression analyses determined relationships with Expanded Disability Status Scale (EDSS) score and dichotomised EDSS outcomes (worsening or stable/improving). RESULTS: Sixty-two people with RRMS (mean age 37.2 ± 10.9 [standard deviation], 48 female) and 11 healthy controls (age 44 ± 11, 7 female) contributed data. Prolonged and supramedian T1 WML components increased longitudinally (176 and 463 voxels, respectively; p < .001), and were associated with EDSS score at baseline (p < .05) and follow-up (supramedian: p < .01; prolonged: p < .05). No cohort-wide median T1 changes were found; however, increasing T1 in WML, NAWM, cortical/deep GM, basal ganglia and thalami was positively associated with EDSS worsening (p < .05). CONCLUSION: T1 is sensitive to brain microstructure changes in early RRMS. Prolonged WML T1 components and subtle changes in NAWM and GM structures are associated with disability. CLINICAL RELEVANCE STATEMENT: MRI T1 brain mapping quantifies disability-associated white matter lesion heterogeneity and subtle microstructural damage in normal-appearing brain parenchyma in recently diagnosed RRMS, and shows promise for early objective disease characterisation and stratification. KEY POINTS: • Quantitative T1 mapping detects brain microstructural damage and lesion heterogeneity in recently diagnosed relapsing-remitting multiple sclerosis. • T1 increases in lesions and normal-appearing parenchyma, indicating microstructural damage, are associated with worsening disability. • Brain T1 measures are objective markers of disability-relevant pathology in early multiple sclerosis.

6.
Pediatr Blood Cancer ; 70(7): e30397, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37101362

RESUMO

BACKGROUND: Nutritional deficiencies are prevalent in sickle cell disease (SCD) and may be associated with worse pain outcomes. Gut dysbiosis has been reported in patients with SCD and may contribute to both nutritional deficiencies and pain. OBJECTIVES: We tested the association of nutrition, fat-soluble vitamin (FSV) deficiency, and gut microbiome composition on clinical outcomes in SCD. Second, we measured the association between diet and exocrine pancreatic function on FSV levels. METHODS: Using case control design, we enrolled children with SCD (n = 24) and matched healthy controls (HC; n = 17, age, sex, race/ethnicity). Descriptive statistics summarized demographic and clinical data. Wilcoxson-rank tests compared FSV levels between cohorts. Regression modeling tested the association between FSV levels and SCD status. Welch's t-test with Satterthwaite adjustment evaluated associations between microbiota profiles, SCD status, and pain outcomes. RESULTS: Vitamin A and D levels were significantly decreased in participants with HbSS as compared to HC (vitamin A, p = < .0001, vitamin D, p = .014) independent of nutritional status. FSV correlated with dietary intake in SCD and HC cohorts. Gut microbial diversity was reduced in hemoglobin SS (HbSS) compared to hemoglobin SC (HbSC) and HC, p = .037 and .059, respectively. The phyla Erysipelotrichaceae and Betaproteobacteria were higher in SCD children reporting the highest quality-of-life (QoL) scores (p = .008 and .049, respectively), while Clostridia were higher in those with lower QoL scores (p = .03). CONCLUSION: FSV deficiencies and gut dysbiosis are prevalent in children with SCA. Gut microbial composition is significantly different in children with SCD with low QoL scores.


Assuntos
Anemia Falciforme , Deficiência de Vitamina D , Humanos , Criança , Projetos Piloto , Estado Nutricional , Vitamina A , Qualidade de Vida , Disbiose/complicações , Anemia Falciforme/complicações , Hemoglobina Falciforme , Vitaminas , Dor
7.
J Med Internet Res ; 25: e44410, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-36881540

RESUMO

BACKGROUND: Vocal biomarker-based machine learning approaches have shown promising results in the detection of various health conditions, including respiratory diseases, such as asthma. OBJECTIVE: This study aimed to determine whether a respiratory-responsive vocal biomarker (RRVB) model platform initially trained on an asthma and healthy volunteer (HV) data set can differentiate patients with active COVID-19 infection from asymptomatic HVs by assessing its sensitivity, specificity, and odds ratio (OR). METHODS: A logistic regression model using a weighted sum of voice acoustic features was previously trained and validated on a data set of approximately 1700 patients with a confirmed asthma diagnosis and a similar number of healthy controls. The same model has shown generalizability to patients with chronic obstructive pulmonary disease, interstitial lung disease, and cough. In this study, 497 participants (female: n=268, 53.9%; <65 years old: n=467, 94%; Marathi speakers: n=253, 50.9%; English speakers: n=223, 44.9%; Spanish speakers: n=25, 5%) were enrolled across 4 clinical sites in the United States and India and provided voice samples and symptom reports on their personal smartphones. The participants included patients who are symptomatic COVID-19 positive and negative as well as asymptomatic HVs. The RRVB model performance was assessed by comparing it with the clinical diagnosis of COVID-19 confirmed by reverse transcriptase-polymerase chain reaction. RESULTS: The ability of the RRVB model to differentiate patients with respiratory conditions from healthy controls was previously demonstrated on validation data in asthma, chronic obstructive pulmonary disease, interstitial lung disease, and cough, with ORs of 4.3, 9.1, 3.1, and 3.9, respectively. The same RRVB model in this study in COVID-19 performed with a sensitivity of 73.2%, specificity of 62.9%, and OR of 4.64 (P<.001). Patients who experienced respiratory symptoms were detected more frequently than those who did not experience respiratory symptoms and completely asymptomatic patients (sensitivity: 78.4% vs 67.4% vs 68%, respectively). CONCLUSIONS: The RRVB model has shown good generalizability across respiratory conditions, geographies, and languages. Results using data set of patients with COVID-19 demonstrate its meaningful potential to serve as a prescreening tool for identifying individuals at risk for COVID-19 infection in combination with temperature and symptom reports. Although not a COVID-19 test, these results suggest that the RRVB model can encourage targeted testing. Moreover, the generalizability of this model for detecting respiratory symptoms across different linguistic and geographic contexts suggests a potential path for the development and validation of voice-based tools for broader disease surveillance and monitoring applications in the future.


Assuntos
Asma , COVID-19 , Doença Pulmonar Obstrutiva Crônica , Insuficiência Respiratória , Humanos , Feminino , Idoso , COVID-19/diagnóstico , Tosse/diagnóstico , Asma/diagnóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico
8.
Magn Reson Chem ; 61(4): 253-267, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36567433

RESUMO

Nuclear quadrupole resonances for 14 N and 17 O nuclei are exquisitely sensitive to interactions with surrounding atoms. As a result, nitrogen and oxygen solid-state nuclear magnetic resonance (ssNMR) provides a powerful tool for investigating structure and dynamics in complex systems. First-principles calculations are increasingly used to facilitate spectral assignment and to evaluate and adjust crystal structures. Recent work combining the strengths of planewave density functional theory (DFT) calculations with a single molecule correction obtained using a higher level of theory has proven successful in improving the accuracy of predicted chemical shielding (CS) tensors and 17 O quadrupolar coupling constants ( C q ). Here we extend this work by examining the accuracy of predicted 14 N and 17 O electric field gradient (EFG) tensor components obtained using alternative planewave-corrections involving cluster and two-body fragment-based calculations. We benchmark the accuracy of CS and EFG tensor predictions for both nitrogen and oxygen using planewave, two-body fragment, and enhanced planewave-corrected techniques. Combining planewave and two-body fragment calculations reduces the error in predicted 17 O C q values by 35% relative to traditional planewave calculations. These enhanced planewave-correction methods improve the accuracy of 17 O and 14 N EFG tensor components by 15% relative to planewave DFT but yield minimal improvement relative to a simple molecular correction. However, in structural environments involving either high symmetry or strong intermolecular interactions, enhanced planewave-corrected methods provide a distinct advantage.

9.
Anal Chem ; 94(15): 5741-5743, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35377605

RESUMO

Nuclear magnetic resonance (NMR) studies involving 17O are increasingly important in molecular biology, material science, and other disciplines. A large number of these studies employ H217O as a source of 17O, and this reliance can be limiting because the high cost of H217O. To overcome this constraint, a recent study proposed a distillation scheme capable of producing significant quantities of H217O at a low cost. Although this method is reported to be effective, the reactions proposed to quantify percent of 17O enrichment are either time intensive or have a risk of errors due to the isotope effect. Here, an alternative reaction scheme is described to measure 17O water that ultimately creates methyl benzoate as the sole 17O-containing product. The proposed reaction is completed in a matter of minutes at room temperature, produces only one 17O product, and requires no clean-up step. The large isotope shift observed in solution NMR between the 13C═16O and 13C═17O resonances allows for integration of the individual peaks. This 13C NMR analysis is found to be highly accurate over a wide enrichment range and is accessible to most NMR spectroscopists.


Assuntos
Água , Espectroscopia de Ressonância Magnética , Isótopos de Oxigênio/química , Tempo de Protrombina , Teste de Stanford-Binet , Água/química
10.
Horm Behav ; 146: 105260, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36122515

RESUMO

Only two studies to date have considered the joint effects of testosterone and cortisol on direct measures of criminal behavior. The current study extends this earlier work by incorporating the direct and interactive effects of baseline hormone measures and hormone change scores in response to social stress. The current study also extends prior work by considering distinct measures of different criminal behavior types and sex differences. Analyses based on a large sample of undergraduates indicated that testosterone had a positive and statistically significant association with impulsive and violent criminal behavior. The interaction of testosterone with cortisol had a negative association with income generating crime. Simple slopes analyses of this interaction indicated testosterone had a positive association with income generating crime when cortisol was low (-1 SD). Associations between hormones and criminal behavior were not moderated by sex.


Assuntos
Hidrocortisona , Testosterona , Humanos , Feminino , Masculino , Hidrocortisona/análise , Testosterona/análise , Saliva/química , Crime , Comportamento Criminoso
11.
Solid State Nucl Magn Reson ; 122: 101832, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36198253

RESUMO

Ab initio methods for predicting NMR parameters in the solid state are an essential tool for assigning experimental spectra and play an increasingly important role in structural characterizations. Recently, a molecular correction (MC) technique has been developed which combines the strengths of plane-wave methods (GIPAW) with single molecule calculations employing Gaussian basis sets. The GIPAW + MC method relies on a periodic calculation performed at a lower level of theory to model the crystalline environment. The GIPAW result is then corrected using a single molecule calculation performed at a higher level of theory. The success of the GIPAW + MC method in predicting a range of NMR parameters is a result of the highly local character of the tensors underlying the NMR observable. However, in applications involving strong intermolecular interactions we find that expanding the region treated at the higher level of theory more accurately captures local many-body contributions to the N15 NMR chemical shielding (CS) tensor. We propose alternative corrections to GIPAW which capture interactions between adjacent molecules at a higher level of theory using either fragment or cluster-based calculations. Benchmark calculations performed on N15 and C13 data sets show that these advanced GIPAW-corrected calculations improve the accuracy of chemical shielding tensor predictions relative to existing methods. Specifically, cluster-based N15 corrections show a 24% and 17% reduction in RMS error relative to GIPAW and GIPAW + MC calculations, respectively. Comparing the benchmark data sets using multiple computational models demonstrates that N15 CS tensor calculations are significantly more sensitive to intermolecular interactions relative to C13. However, fragment and cluster-based corrections that include direct hydrogen bond partners are sufficient for optimizing the accuracy of GIPAW-corrected methods. Finally, GIPAW-corrected methods are applied to the particularly challenging NMR spectral assignment of guanosine dihydrate which contains two guanosine molecules in the asymmetric unit.


Assuntos
Guanosina , Espectroscopia de Ressonância Magnética/métodos , Ligação de Hidrogênio
12.
Postgrad Med J ; 98(1160): 461-465, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33589491

RESUMO

PURPOSE OF THE STUDY: To evaluate documentation of a target oxygen saturation (SpO2) range and ability to achieve this range in acutely unwell inpatients. STUDY DESIGN: In this single-centre audit, patients with discharge diagnoses of pneumonia, heart failure and exacerbation of asthma or COPD admitted to Wellington Regional Hospital, New Zealand between 1 June 2019 and 31 August 2019 who received oxygen were identified. In those with a documented target SpO2 range, the proportion of SpO2 measurements in the observation chart which were within, above and below range were determined as well as the maximum and minimum SpO2. Regression analysis was performed to determine whether these outcomes were influenced by the prescribed range, high-dependency care or the number of adjustments to oxygen administration. RESULTS: 268 admissions were screened. Of the 100 eligible admissions who received oxygen, a target SpO2 range was documented in 62. The mean (SD) proportion of SpO2 measurements within range was 56.2 (30.6)%. A hypercapnic target SpO2 range was associated with a higher probability of an SpO2 above range; multivariate OR 5.34 (95% CI 1.65 to 17.3, p=0.006) and a lower probability of an SpO2 below range; multivariate OR 0.25 (95% CI 0.08 to 0.80) p=0.02. The mean (SD) maximum SpO2 was similar in those with a target range of 92%-96% versus a hypercapnic range; 96.2 (3.0)% and 95.2 (3.4)%, respectively. CONCLUSIONS: Oxygen prescription and delivery in this clinical setting was suboptimal. SpO2 values above the designated range are common, particularly in patients with a hypercapnic target range.


Assuntos
Saturação de Oxigênio , Oxigênio , Documentação , Hospitalização , Humanos , Pacientes Internados , Oximetria
13.
Chemphyschem ; 22(10): 1008-1017, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33604988

RESUMO

The ability to theoretically predict accurate NMR chemical shifts in solids is increasingly important due to the role such shifts play in selecting among proposed model structures. Herein, two theoretical methods are evaluated for their ability to assign 15 N shifts from guanosine dihydrate to one of the two independent molecules present in the lattice. The NMR data consist of 15 N shift tensors from 10 resonances. Analysis using periodic boundary or fragment methods consider a benchmark dataset to estimate errors and predict uncertainties of 5.6 and 6.2 ppm, respectively. Despite this high accuracy, only one of the five sites were confidently assigned to a specific molecule of the asymmetric unit. This limitation is not due to negligible differences in experimental data, as most sites exhibit differences of >6.0 ppm between pairs of resonances representing a given position. Instead, the theoretical methods are insufficiently accurate to make assignments at most positions.

14.
Environ Sci Technol ; 55(3): 1832-1841, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33439627

RESUMO

Continued access to sanitation and the improvements to public health that it provides requires safe fecal sludge management (FSM). Trained service providers offer the best path to achieve safe FSM in rural communities, but this service industry is hindered by a lack of understanding household valuation of FSM services in rural Cambodia. Using a discrete choice experiment, we characterize rural households' preferences for four different FSM-service attributes across five provinces. We find that rural households prefer preventing contact with fecal sludge (FS) most among the tested FSM-service attributes, followed by reducing foul odor and producing fertilizer from FS. Reducing time to service delivery was also preferred comparably to producing fertilizer from FS when time to service delivery increased to 4 weeks. Preferences were also analyzed by province, poverty, and education, providing regional and demographic-specific results. Based on the study's results, we recommend that Cambodia's rural sanitation sector develop an FSM-service model that focuses on preventing human contact with FS. Premium levels of service that reduce foul odor and/or provide fertilizer from FS should be offered. Development practitioners should consider the strong preference heterogeneity for FSM-service attributes of households across and within provinces and demographics. These recommendations will provide practical benefits to FSM safety and ultimately improve public health.


Assuntos
População Rural , Esgotos , Camboja , Características da Família , Humanos , Saneamento
15.
BMC Pulm Med ; 21(1): 332, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702236

RESUMO

BACKGROUND: Both inadequate and excessive administration of oxygen to acutely unwell patients results in risk of harm. Guidelines recommend titration of oxygen to achieve a target oxygen saturation (SpO2) range. Information regarding whether this is being achieved is limited. METHODS: In this two-centre non-interventional study we used continuous pulse oximetry in acutely unwell medical patients over a 24-h period to determine the proportion of time spent with SpO2 within the prescribed target range and whether this is influenced by the target range, age, care in a high-dependency area and the number of oxygen adjustments. RESULTS: Eighty participants were included in the analysis. The mean (SD) proportion of time spent in target range was 55.6% (23.6), this was lower in those with a reduced hypercapnic target range (88-92% or below) compared to those with a range of 92-96%; difference - 13.1% (95% CI - 3.0 to - 23.2), P = 0.012. The proportion of time spent above range was 16.2% (22.9); this was higher in those with a reduced hypercapnic range; difference 21.6% (31.4 to 12), P < 0.001. The proportion of time below range was 28.4% (25.2); there was no difference between target ranges. The proportion of time spent in range was higher for those in a high dependency area in the multivariate model; difference 15.5% (95% CI 2.3 to 28.7), P = 0.02. CONCLUSIONS: Medical patients receiving oxygen in a ward setting spend significant periods of time with SpO2 both above and below the prescribed target range while receiving oxygen therapy.


Assuntos
Oximetria/métodos , Oxigenoterapia/efeitos adversos , Saturação de Oxigênio/fisiologia , Oxigênio/administração & dosagem , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipercapnia/epidemiologia , Hipercapnia/terapia , Masculino , Nova Zelândia/epidemiologia , Oxigenoterapia/métodos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Tempo
16.
Magn Reson Chem ; 59(1): 23-33, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32687644

RESUMO

The connectivity, conformation, tautomeric form, and dynamics of a new depsidone (perisalazinic acid) were characterized using one-bond 13 C13 C NMR scalar couplings (1 JCC ) obtained from the INADEQUATE experiment. Characterization of perisalazinic acid using more conventional NMR techniques is problematic due to the extremely limited number of CH protons present. In the present study, 81 candidate structures were considered and a best fit structure was selected by comparing computed 1 JCC values for each candidate to 15 experimental values. Of the six flexible moieties in perisalazinic acid, three are adequately represented by a single orientation stabilized by intramolecular hydrogen bonding. The three remaining groups are present as mixtures of conformers with two sites consisting of a pair of conformations and another disordered over six orientations. This study demonstrates the feasibility of complete three-dimensional structural characterization of an unknown using only theoretical and experimental 1 JCC values.

17.
Int J Cancer ; 146(2): 531-541, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31584185

RESUMO

We have developed an oncolytic Newcastle disease virus (NDV) that has potent in vitro and in vivo anti-tumor activities and attenuated pathogenicity in chickens. In this ex vivo study using the same recombinant NDV backbone with GFP transgene (NDV-GFP, designated as rNDV), we found that rNDV induces maturation of monocyte-derived immature dendritic cells (iDCs) by both direct and indirect mechanisms, which promote development of antigen-specific T cell responses. Addition of rNDV directly to iDCs culture induced DC maturation, as demonstrated by the increased expression of costimulatory and antigen-presenting molecules as well as the production of type I interferons (IFNs). rNDV infection of the HER-2 positive human breast cancer cell line (SKBR3) resulted in apoptotic cell death, release of proinflammatory cytokines, and danger-associated molecular pattern molecules (DAMPs) including high-mobility group protein B1 (HMGB1) and heat shock protein 70 (HSP70). Addition of rNDV-infected SKBR3 cells to iDC culture resulted in greatly enhanced upregulation of the maturation markers and release of type I IFNs by DCs than rNDV-infected DCs only. When co-cultured with autologous T cells, DCs pre-treated with rNDV-infected SKBR3 cells cross-primed T cells in an antigen-specific manner. Altogether, our data strongly support the potential of oncolytic NDV as efficient therapeutic agent for cancer treatment.


Assuntos
Apresentação Cruzada , Células Dendríticas/imunologia , Imunoterapia/métodos , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Animais , Chlorocebus aethiops , Técnicas de Cocultura , Células Dendríticas/metabolismo , Feminino , Células HeLa , Humanos , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Neoplasias/imunologia , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/imunologia , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia , RNA/administração & dosagem , RNA/genética , RNA Viral/administração & dosagem , RNA Viral/genética , Linfócitos T/imunologia , Células Vero
18.
Cancer Immunol Immunother ; 69(6): 1015-1027, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32088771

RESUMO

Oncolytic virus (OV) therapy is an emerging approach with the potential to redefine treatment options across a range of cancer indications and in patients who remain resistant to existing standards of care, including immuno-oncology (IO) drugs. MEDI5395, a recombinant Newcastle disease virus (NDV), engineered to express granulocyte-macrophage colony-stimulating factor (GM-CSF), exhibits potent oncolytic activity. It was hypothesized that activation of immune cells by MEDI5395, coupled with its oncolytic activity, would enhance the priming of antitumor immunity. Using MEDI5395 and recombinant NDVs encoding fluorescent reporter genes, we demonstrated preferential virus uptake and non-productive infection in myeloid cells, including monocytes, macrophages, and dendritic cells (DCs). Infection resulted in immune-cell activation, with upregulation of cell surface activation markers (e.g., CD80, PD-L1, HLA-DR) and secretion of proinflammatory cytokines (IFN-α2a, IL-6, IL-8, TNF-α). Interestingly, in vitro M2-polarized macrophages were more permissive to virus infection than were M1-polarized macrophages. In a co-culture system, infected myeloid cells were effective virus vectors and mediated the transfer of infectious NDV particles to tumor cells, resulting in cell death. Furthermore, NDV-infected DCs stimulated greater proliferation of allogeneic T cells than uninfected DCs. Antigens released after NDV-induced tumor cell lysis were cross-presented by DCs and drove activation of tumor antigen-specific autologous T cells. MEDI5395 therefore exhibited potent immunostimulatory activity and an ability to enhance antigen-specific T-cell priming. This, coupled with its tumor-selective oncolytic capacity, underscores the promise of MEDI5395 as a multimodal therapeutic, with potential to both enhance current responding patient populations and elicit de novo responses in resistant patients.


Assuntos
Vírus da Doença de Newcastle/genética , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Linhagem Celular Tumoral , Vetores Genéticos , Humanos , Imunidade Inata
19.
Eur Respir J ; 55(1)2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31558659

RESUMO

BACKGROUND: The proportion of the efficacy of high-dose inhaled corticosteroids (ICS) in oral corticosteroid-dependent asthma that is due to systemic effects is uncertain. This study aimed to estimate the ICS dose-response relationship for oral corticosteroid-sparing effects in oral corticosteroid-dependent asthma, and to determine the proportion of oral corticosteroid-sparing effects due to their systemic effects, based on the comparative dose-response relationship of ICS versus oral corticosteroids on adrenal suppression. METHODS: Systematic review and meta-analysis of randomised controlled trials reporting oral corticosteroid-sparing effects of high-dose ICS in oral corticosteroid-dependent asthma. In addition, reports of oral corticosteroid to ICS dose-equivalence in terms of adrenal suppression were retrieved. The primary outcome was the proportion of the oral corticosteroid-sparing effect of ICS that could be attributed to systemic absorption, per 1000 µg increase of ICS, expressed as a ratio. This ratio estimates the oral corticosteroid sparing effect of ICS due to systemic effects. RESULTS: 11 studies including 1283 participants reporting oral corticosteroid-sparing effects of ICS were identified. The prednisone dose decrease per 1000 µg increase in ICS varied from 2.1 mg to 4.9 mg, depending on the type of ICS. The ratio of the prednisone-sparing effect due to the systemic effects per 1000 µg of fluticasone propionate was 1.02 (95% CI 0.68-2.08) and for budesonide was 0.93 (95% CI 0.63-1.89). CONCLUSION: In patients with oral corticosteroid-dependent asthma, the limited available evidence suggests that the majority of the oral corticosteroid-sparing effect of high-dose ICS is likely to be due to systemic effects.


Assuntos
Antiasmáticos , Asma , Administração por Inalação , Corticosteroides/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Fluticasona/uso terapêutico , Humanos
20.
Chemistry ; 26(1): 230-236, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31613014

RESUMO

The principal values of the 13 C chemical shift tensor for the ß and δ polymorphs of π-[TTF⋅⋅⋅TCNE] (TTF=tetrathiafulvalene; TCNE=tetracyanoethylene) have been analyzed to understand the abnormally long intra-dimer bonding of singlet π-[TTFδ+ ⋅⋅⋅TCNEδ- ]. These structures possess 12 intradimer contacts <3.40 Å, with the shortest intra π-[TTF⋅⋅⋅TCNE] separations involving 2-center (2c) C-S and 3c C-C-C orbital overlap contributions between the [TTF]δ+ and [TCNE]δ- . This solid-state NMR study compares the [TTF⋅⋅⋅TCNE] 13 C tensor data against previously reported π-[TTF]2 2+ and π-[TCNE]2 2- homo-dimers to determine how the tensor principal values change as a function of electronic structure for both TTF and TCNE moieties. In the ß and δ phases of [TTF⋅⋅⋅TCNE], the TCNE ethylenic 13 C shift tensors predict TCNE oxidation states of -0.46 and -0.73, respectively. The TTF sites are less similar to benchmark 13 C data with the ß-phase differing primarily in the ethylenic π-electrons. The δ form differs significantly from the homo-dimer data at all principal values at both the ethylenic and CH sites, indicating changes to both the π-electrons and σ-bonds. In both hetero-dimer phases, the NMR changes supports long bond formation at nitrile and CH sites not observed in homo-dimers.

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