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1.
J Am Chem Soc ; 141(7): 2838-2842, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30698426

RESUMEN

We describe the 3-iodopropyl acetal moiety as a simple cleavable unit that undergoes acid catalyzed hydrolysis to liberate HI (p Ka ∼ -10) and acrolein stoichiometrically. Integrating this unit into linear and network polymers gives a class of macromolecules that undergo a new mechanism of degradation with an acid amplified, sigmoidal rate. This trigger-responsive self-amplified degradable polymer undergoes accelerated rate of degradation and agent release.

2.
Immun Inflamm Dis ; 12(7): e1315, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39031511

RESUMEN

BACKGROUND: Asthma is routinely treated with inhaled corticosteroids (ICS). Asthma patients on ICS are at increased risk of adrenal suppression, a potentially serious effect of long-term glucocorticoid exposure; however, this relationship is poorly understood. Therefore, this study aims to identify metabolite biomarkers related to adrenal suppression in asthma patients taking ICS. METHODS: A total of 571 urine metabolites from 200 children with asthma on ICS in the Pharmacogenetics of Adrenal Suppression with Inhaled Steroids (PASS) cohort were profiled. Samples were grouped by peak plasma cortisol measurement as adrenal sufficient (>350 nmol/L) or insufficient (≤350 nmol/L) (outcome). Regression and discriminant-based statistical models combined with network analyses were utilized to assess relationships between metabolites and the outcome. Finally, prioritized metabolites were validated using data from an ancillary study of the Childhood Asthma Management (CAMP) cohort with similar characteristics to PASS. RESULTS: Ninety metabolites were significantly associated with adrenal suppression, of which 57 also could discriminate adrenal status. While 26 metabolites (primarily steroids) were present at lower levels in the adrenal insufficient patients, 14 were significantly elevated in this group; the top metabolite, mannitol/sorbitol, was previously associated with asthma exacerbations. Network analyses identified unique clusters of metabolites related to steroids, fatty acid oxidation, and nucleoside metabolism, respectively. Four metabolites including urocanic acid, acetylcarnitine, uracil, and sorbitol were validated in CAMP cohort for adrenal suppression. CONCLUSIONS: Urinary metabolites differ among asthma patients on ICS, by adrenal status. While steroid metabolites were reduced in patients with poor adrenal function, our findings also implicate previously unreported metabolites involved in amino acid, lipid, and nucleoside metabolism.


Asunto(s)
Corticoesteroides , Asma , Metabolómica , Humanos , Asma/tratamiento farmacológico , Asma/orina , Asma/sangre , Asma/diagnóstico , Niño , Masculino , Femenino , Administración por Inhalación , Metabolómica/métodos , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Biomarcadores/orina , Biomarcadores/sangre , Adolescente , Metaboloma/efectos de los fármacos , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/sangre , Insuficiencia Suprarrenal/orina , Insuficiencia Suprarrenal/etiología , Insuficiencia Suprarrenal/tratamiento farmacológico , Preescolar , Hidrocortisona/sangre , Hidrocortisona/orina , Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/efectos de los fármacos , Estudios de Cohortes
3.
Front Plant Sci ; 14: 1326882, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38288404

RESUMEN

Microbial communities play an important role in the growth and development of plants, including plant immunity and the decomposition of complex substances into absorbable nutrients. Hence, utilizing beneficial microbes becomes a promising strategy for the optimization of plant growth. The objective of this research was to explore the root bacterial profile across different soybean genotypes and the change in the microbial community under soybean cyst nematode (SCN) infection in greenhouse conditions using 16S rRNA sequencing. Soybean genotypes with soybean cyst nematode (SCN) susceptible and resistant phenotypes were grown under field and greenhouse conditions. Bulked soil, rhizosphere, and root samples were collected from each replicate. Sequencing of the bacterial 16S gene indicated that the bacterial profile of soybean root and soil samples partially overlapped but also contained different communities. The bacterial phyla Proteobacteria, Actinobacteria, and Bacteroidetes dominate the soybean root-enriched microbiota. The structure of bacteria was significantly affected by sample year (field) or time point (greenhouse). In addition, the host genotype had a small but significant effect on the diversity of the root microbiome under SCN pressure in the greenhouse test. These differences may potentially represent beneficial bacteria or secondary effects related to SCN resistance.

4.
Artículo en Inglés | MEDLINE | ID: mdl-35847193

RESUMEN

Introduction and importance: Anterior Cruciate Ligament (ACL) reconstruction surgery has been proven to be closely related to the graft healing process, which can last up to 12 months after surgery. In recent years, through various biomechanical and clinical studies, Internal Brace Ligament Augmentation (IBLA) has been shown to protect the graft during these early postoperative stages and improve the outcome of ACL reconstruction. We present this case series of all-inside arthroscopic anterior cruciate ligament reconstruction with IBLA using semitendinosus tendon autografts, with the goal of evaluating postoperative clinical and patient-reported outcomes. Case presentation: A total of 37 patients who underwent all-inside arthroscopic anterior cruciate ligament reconstruction with IBLA using only semitendinosus tendon autografts, were evaluated, in terms of patient reported outcome and clinical assessment, during the 3, 6 and 12 months post-operative follow-up. Results: The mean Lysholm Knee score at the final follow-up was 94,03 +- 3,65 with a difference of 34,59 +- 5,52 to the baseline level. International Knee Documentation Committee (IKDC) classification rated 30 cases of grade A and 7 cases of grade B. In terms of clinical tests and knee's range of motion, all patients have returned to normal, and no cases of re-rupture or other severe complications were found. Clinical discussion: Early follow-up patient reported outcomes have provided good to great results for the 37 patients who underwent all-inside arthroscopic anterior cruciate ligament reconstruction with IBLA using semitendinosus tendon autografts and no cases of graft failure or other notable complication has been discovered. Clinical findings suggest improved knee's integrity and range of movement during the early stages, which may promote early rehabilitation, however future long-term comparative studies are needed. Conclusion: IBLA with all-inside ACL reconstructions using only semitendinosus autograft has provided good to great results however, future long-term comparative studies are needed.

5.
ACS Macro Lett ; 11(1): 72-77, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35574784

RESUMEN

Polyelectrolytes, a class of polymer with ionized functional groups in their repeating units, are widely used in various applications. Many ionized groups have been incorporated into polyelectrolytes, but aromatic anions are rarely investigated. Here, we first successfully incorporate a stable tetracyanocyclopentadienide (TCCp) aromatic anion into polynorbornene (PNb)-based electrolytes (PNb-TCCp) through ring-opening metathesis polymerization (ROMP) with controllable molecular weight and low polydispersity. PNb-TCCp shows a high ionic conductivity of 4.5 × 10-5 S/cm in thin films. Due to its highly stable aromatic anion groups and favorable interactions with aromatic cations, it could improve thermal stability of doped conjugated polymers. Pairing with doped poly(3,4-ethylenedioxythiophene) (PEDOT) through salt metathesis, the generated poly ion complex PEDOT:PNb-TCCp retains its conductivity up to 180 °C.


Asunto(s)
Polímeros , Aniones , Conductividad Eléctrica , Polielectrolitos , Polimerizacion
6.
Int J Surg Case Rep ; 88: 106492, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34655974

RESUMEN

INTRODUCTION AND IMPORTANCE: Meniscal tear is one of the most common knee injuries and knee surgery procedures. It is frequently associated with an anterior cruciate ligament (ACL) injury. We conducted this study, on patients with ACL reconstruction surgeries, which were occasionally accompanied by meniscal tears, in order to determine the diagnostic value of clinical examinations for meniscal tear, both individually and in combination, in correlations to magnetic resonance imaging (MRI) scans, with the goal of improving clinical diagnosis for patients with meniscal injuries in particular, as well as meniscal injuries associated with cruciate ligament knee injuries. CASE PRESENTATION: 50 patients were thoroughly clinically examined, using Joint line tenderness, Thessaly test, McMurray's test, Apley's test followed by MRI, before their scheduled ACL reconstruction arthroscopic surgeries. The meniscal tears were then identified during the procedure, and were treated, if necessary. The data before and after the surgery was taken into calculating, with arthroscopic findings serving as the gold standard. RESULTS: the sensitivity, specificity and accuracy of each clinical tests and MRI scans respectively were: for medial meniscus, Joint line tenderness (70%; 53,3%; 60%); McMurray's test (80%; 73,3%: 76%); Apley's test (65%; 70%; 68%); Thessaly test(70%; 76,7%; 74%); MRI (90%; 83,3%; 86%); lateral meniscus: Joint line tenderness (73%; 66,7%; 70%); McMurray's test (69,2%; 75%: 72%); Apley's test (69,2%; 70,8%; 70%); Thessaly test (73,1%; 75%; 74%); MRI (88,5%; 87,5%; 88%). However, when combining at least two positive tests into a single composite test, the diagnostic value is considerably enhanced with sensitivity, specificity and accuracy of 85%, 73,3%, 78% for medial meniscus, 92,3%, 87,5%, 90% for lateral meniscus. CLINICAL DISCUSSION: Clinical tests are essential for diagnosis of meniscal tears, although inconsistent. A composite test consisting of at least two positive tests can considerably enhance the diagnostic value, even comparable to MRI scans. However, after the clinical examination, MRI is still necessary for the diagnostic process of meniscal injuries in particular, as well as meniscal injuries associated with cruciate ligament knee injuries. CONCLUSION: The combination of clinical tests and MRI images will give a precise diagnosis as well as surgical indication for meniscus injury in patients with anterior cruciate ligament tear.

7.
Orthop Surg ; 13(4): 1437-1442, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33942980

RESUMEN

BACKGROUND: The traumatic dislocation of the radial head in children is commonly treated by closed reduction. Sometimes, however, this strategy of treatment may not be effective due to the location of soft tissues in the radio-shoulder joint. The literature presents a few cases of the irreducible radial head dislocation with ulnar plastic deformation. Because it is a relatively rare condition, such a traumatic dislocation can be easily missed. Neglected injuries can lead to unwanted complications and unpredictable surgical outcomes. CASE PRESENTATION: This study presents a relatively rare case of traumatic radial head dislocation with ulnar plastic deformation in a 3-year-old child, which was successfully treated by open reduction. The examined case did not require osteotomy and ligamentous reconstruction. The initial attempt of closed reduction failed due to annular ligament interposition, which has been detected on MRI. After 3 months of treatment, the range of motion of the operated arm gradually improved. At the 6-month follow-up, the Mayo elbow-performance score indicated an excellent treatment outcome. CONCLUSIONS: The delayed treatment of radial head dislocation with ulnar plastic deformation can hinder the supination and pronation of the forearm, resulting in elbow/forearm deformity. The earlier this condition is detected, the easier it will be to treat it and the better the treatment outcome will be. The examined case of irreversible traumatic dislocation, successfully treated by open reduction, may help to treat radial head dislocation better.


Asunto(s)
Articulación del Codo/cirugía , Luxaciones Articulares/cirugía , Ligamentos Articulares/cirugía , Radio (Anatomía)/cirugía , Preescolar , Femenino , Humanos , Ligamentos Articulares/lesiones , Radio (Anatomía)/lesiones , Rango del Movimiento Articular , Cúbito/lesiones , Lesiones de Codo
8.
Phys Chem Chem Phys ; 11(44): 10340-9, 2009 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-19890518

RESUMEN

Thirty-eight atom Cu-Au clusters have been studied because this is a magic size for a complete truncated octahedral cluster. The clusters are investigated using two approaches, at different levels of theory, which are complementary. The first is an empirical potential (EP) approach which is used together with a genetic algorithm (GA) to tackle the problems of global optimization-i.e., searching for lowest-lying energy structures. The second is an ab initio approach based on density functional theory (DFT) which is used to reoptimize the initial EP structures (both global minima and other low energy isomers). Structural distributions and energy landscapes, including calculations of electronic energy gaps for all compositions of Cu(38-n)Au(n), are investigated. The energy competition between different structural motifs and different configurations are studied at the DFT level. The analysis of mixing and segregation effects results in confirmation of the preference for Cu(core)-Au(shell) configurations at the DFT level. Charge transfer is calculated for different structural motifs of Cu(19)Au(19) to study the role of this phenomenon in driving cluster configuration.

9.
ACS Appl Mater Interfaces ; 11(4): 4169-4177, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30608143

RESUMEN

The limited availability of solution-processable ion storage materials, both inorganic and organic, hinders the adoption of roll-to-roll manufacturing for polymer electrochromic devices (ECDs). The n-type transition metal oxides are known for their ion storage properties. However, the fabrication methods of their amorphous metal oxide thin films typically involve sputtering, thermal deposition, electrical deposition, or sol-gel deposition followed by high-temperature thermal annealing (>300 °C), thus making them incompatible for low-cost roll-to-roll manufacturing on flexible substrates. In this study, we report the synthesis of amorphous niobium oxide(a-Nb2O5) thin films from sol-gel precursors through the combination of photoactivation and low-temperature thermal annealing (150 °C). Coupled with p-type electrochromic polymers (ECPs), solution-processed a-Nb2O5 thin films were evaluated as a minimally color changing counter electrode (MCC-CE) material for electrochromic devices. We found that ultraviolet ozone (UVO) treated and 150 °C thermally annealed (UVO-150 °C) a-Nb2O5 thin films show excellent electrochemical properties and cycling stability. Notably, a-Nb2O5/ECP-magenta ECD has a high optical contrast of ∼70% and a fast switching time (bleaching and coloring time of 1.6 and 0.5 s for reaching 95% of optical contrast). In addition, the ECD demonstrates a high coloration efficiency of ∼849.5 mC cm-2 and a long cycling stability without a noticeable decay up to 3000 cycles.

10.
Front Plant Sci ; 10: 401, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31031779

RESUMEN

Soybean cyst nematode (Heterodera glycines Ichinohe) (SCN) is the most destructive pest affecting soybeans [Glycine max (L.) Merr.] in the U.S. To date, only two major SCN resistance alleles, rhg1 and Rhg4, identified in PI 88788 (rhg1) and Peking (rhg1/Rhg4), residing on chromosomes (Chr) 18 and 8, respectively, have been widely used to develop SCN resistant cultivars in the U.S. Thus, some SCN populations have evolved to overcome the PI 88788 and Peking derived resistance, making it a priority for breeders to identify new alleles and sources of SCN resistance. Toward that end, 461 soybean accessions from various origins were screened using a greenhouse SCN bioassay and genotyped with Illumina SoySNP50K iSelect BeadChips and three KASP SNP markers developed at the Rhg1 and Rhg4 loci to perform a genome-wide association study (GWAS) and a haplotype analysis at the Rhg1 and Rhg4 loci. In total, 35,820 SNPs were used for GWAS, which identified 12 SNPs at four genomic regions on Chrs 7, 8, 10, and 18 that were significantly associated with SCN resistance (P < 0.001). Of those, three SNPs were located at Rhg1 and Rhg4, and 24 predicted genes were found near the significant SNPs on Chrs 7 and 10. KASP SNP genotyping results of the 462 accessions at the Rhg1 and Rhg4 loci identified 30 that carried PI 88788-type resistance, 50 that carried Peking-type resistance, and 58 that carried neither the Peking-type nor the PI 88788-type resistance alleles, indicating they may possess novel SCN resistance alleles. By using two subsets of SNPs near the Rhg1 and Rhg4 loci obtained from SoySNP iSelect BeadChips, a haplotype analysis of 461 accessions grouped those 58 accessions differently from the accessions carrying Peking or PI 88788 derived resistance, thereby validating the genotyping results at Rhg1 and Rhg4. The significant SNPs, candidate genes, and newly characterized SCN resistant accessions will be beneficial for the development of DNA markers to be used for marker-assisted breeding and developing soybean cultivars carrying novel sources of SCN resistance.

11.
Science ; 362(6419): 1131-1134, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30523104

RESUMEN

Although high-temperature operation (i.e., beyond 150°C) is of great interest for many electronics applications, achieving stable carrier mobilities for organic semiconductors at elevated temperatures is fundamentally challenging. We report a general strategy to make thermally stable high-temperature semiconducting polymer blends, composed of interpenetrating semicrystalline conjugated polymers and high glass-transition temperature insulating matrices. When properly engineered, such polymer blends display a temperature-insensitive charge transport behavior with hole mobility exceeding 2.0 cm2/V·s across a wide temperature range from room temperature up to 220°C in thin-film transistors.

12.
Diabetes Res Clin Pract ; 96(3): e63-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22342137

RESUMEN

Eighteen Vietnamese type 1 diabetic patients presented with ketoacidosis were serially recruited from three tertiary cares. They had mean age (±SD) 23.5±4.1years, median of blood glucose [interquartile range] 28.2 [24.3-31.3]mmol/L, pH 7.255 [7.232-7.285], C-peptide 0.265 [0.098-0.472]nmol/L. 61% were negative for both anti-GAD and ICA tests.


Asunto(s)
Autoanticuerpos/sangre , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/complicaciones , Cetoacidosis Diabética/inmunología , Hemoglobina Glucada/metabolismo , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/inmunología , Cetoacidosis Diabética/sangre , Cetoacidosis Diabética/epidemiología , Femenino , Humanos , Masculino , Vietnam/epidemiología , Adulto Joven
13.
J R Soc Interface ; 9(72): 1705-12, 2012 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-22399790

RESUMEN

We report a novel biochemical method based on the sacrificial hydrogen strategy to synthesize bimetallic gold (Au)-palladium (Pd) nanoparticles (NPs) with a core/shell configuration. The ability of Escherichia coli cells supplied with H(2) as electron donor to rapidly precipitate Pd(II) ions from solution is used to promote the reduction of soluble Au(III). Pre-coating cells with Pd(0) (bioPd) dramatically accelerated Au(III) reduction, with the Au(III) reduction rate being dependent upon the initial Pd loading by mass on the cells. Following Au(III) addition, the bioPd-Au(III) mixture rapidly turned purple, indicating the formation of colloidal gold. Mapping of bio-NPs by energy dispersive X-ray microanalysis suggested Au-dense core regions and peripheral Pd but only Au was detected by X-ray diffraction (XRD) analysis. However, surface analysis of cleaned NPs by cyclic voltammetry revealed large Pd surface sites, suggesting, since XRD shows no crystalline Pd component, that layers of Pd atoms surround Au NPs. Characterization of the bimetallic particles using X-ray absorption spectroscopy confirmed the existence of Au-rich core and Pd-rich shell type bimetallic biogenic NPs. These showed comparable catalytic activity to chemical counterparts with respect to the oxidation of benzyl alcohol, in air, and at a low temperature (90°C).


Asunto(s)
Escherichia coli/metabolismo , Oro , Nanopartículas del Metal/química , Paladio , Alcohol Bencilo/química , Catálisis , Oro/química , Oro/metabolismo , Hidrógeno/metabolismo , Nanopartículas del Metal/ultraestructura , Oxidación-Reducción , Paladio/química , Paladio/metabolismo , Difracción de Rayos X
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