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1.
J Am Chem Soc ; 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33443999

RESUMO

The effective capture and storage of radioiodine are of worldwide interest for sustainable nuclear energy. However, the direct observation of ambiguous binding sites that accommodate iodine is extremely rare. We presented herein a crystallographic visualization of the binding of iodine within mesoporous cages assembled from aluminum molecular rings. These nanocages are formed through π-π interactions between adjacent aluminum molecular rings. Compared with the general nanotubes arrangement, the supramolecular nanocage isomer exhibits better iodine adsorption behavior. The robust molecular nanocages demonstrate a high iodine vapor saturation uptake capacity of 50.3 wt % at 80 °C. Furthermore, the resulting adsorbent can be recycled. Single-crystal X-ray diffraction reveals binding sites of molecular I2 within the pores of the phenyl-based linkers stabilized by the strong I···π interactions. These compounds represent an excellent model to deduce the trapping mechanism of guest molecules interacting with the host. In addition, this work develops a promising cluster-based aluminum material as iodine adsorbents.

2.
J Phys Chem Lett ; : 1131-1137, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475363

RESUMO

In this work, we explore the interfacial properties of the C60-Py@MAPbI3 heterojunction of the PbI-terminated MAPbI3(001) surface and pyridine-functionalized C60-Py fullerene derivative through both collinear and noncollinear density functional theory calculations with and without spin-orbit coupling (SOC) effects. C60-Py is bound to the MAPbI3 surface through interfacial Pb-O and Pb-N bonds. Although C60-Py@MAPbI3 is predicted to be the same type II heterojunction at all of the computational levels considered, the SOC effects largely decrease the energy gap of the first conduction bands of C60-Py and MAPbI3, thereby accelerating the interfacial electron transfer. Further dynamics simulations show that the inclusion of the SOC effects induces the transfer of approximately 80% of electrons from MAPbI3 to C60-Py within 1 ps. The work demonstrates that the SOC effects are indispensable for the interfacial properties of C60-Py@MAPbI3 and could also play a non-negligible role in tuning the optoelectronic properties of fullerene-based or similar perovskite devices.

3.
J Phys Chem Lett ; : 1207-1213, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482068

RESUMO

The extensive application of long-range corrected hybrid functionals highlights the importance of further improving their accuracy. Unlike common long-range corrected hybrid functionals mainly focusing on the exchange part, range-separated correlation and its role in long-range corrected hybrid functionals are the main concerns of this work. To this end, we present theory on the derivation of the range-separated correlation, whose reliability and validity are proved by the agreement with the full CI on the test of the short-range correlation energy. The tests on various properties indicate that the long-range part of the LYP functional cannot effectively capture the long-range correlation effect required in LC-BLYP, whose absence instead results in a better XC functional. This new functional significantly improves LC-BLYP on all the tests in this work, with an accuracy on par with or even greater than the widely recognized CAM-B3LYP method for some applications, while maintaining the important -1/r asymptotic behavior of the XC potential. The advances and insights gained in this work are useful for the application and development of long-range corrected hybrid functionals, while emphasizing the significance of developing effective and low-cost long-range correlation functionals.

4.
J AOAC Int ; 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33484243

RESUMO

BACKGROUND: HuaTanJiangQi capsule (HTJQ) is a classical Chinese medicine compound preparation, mainly used for clinically treating and improving the Chronic Obstructive Pulmonary Disease (COPD) in China. OBJECTIVE: To establish a rapid and efficient analytical method for the identification and characterization of chemical constituents in HTJQ based on ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS). METHODS: UPLC-QTOF-MS was used to rapidly separate and identify the chemical constituents of HTJQ via gradient elution system. The accurate mass data of the protonated and deprotonated molecules and fragment ions was detected in positive and negative ion modes. Compounds of HTJQ can be identified and assigned by analyzing accurate mass measurements and ion fragmentation mechanisms and comparing them with the chemical compositions database. RESULTS: A total of 61 compounds in HTJQ were separated and identified, including 14 flavonoids, 16 organic acids, 4 isothiocyanic acids, 8 butyl phthalides, 2 alkaloids, 10 terpenoids, 4 methoxyphenols and furanocoumarins, 3 other compounds. The chemical compounds of HTJQ were identified and elucidated comprehensively for the first time. CONCLUSIONS: A rapid, accurate, and efficient UPLC-QTOF-MS method has been developed for the identification of the chemical components and applied to simultaneously evaluate the quality and effectiveness of the HTJQ. HIGHLIGHTS: Systematic identification of chemical constituents in HTJQ can provide a scientific and reasonable basis for the application of HTJQ in the clinical treatment of COPD.

5.
Nat Commun ; 12(1): 385, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452266

RESUMO

Chemically synthesized metal nanowires are promising building blocks for next-generation photonic integrated circuits, but technological implementation in monolithic integration will be severely hampered by the lack of controllable and precise manipulation approaches, due to the strong adhesion of nanowires to substrates in non-liquid environments. Here, we demonstrate this obstacle can be removed by our proposed earthworm-like peristaltic crawling motion mechanism, based on the synergistic expansion, friction, and contraction in plasmon-driven metal nanowires in non-liquid environments. The evanescently excited surface plasmon greatly enhances the heating effect in metal nanowires, thereby generating surface acoustic waves to drive the nanowires crawling along silica microfibres. Advantages include sub-nanometer positioning accuracy, low actuation power, and self-parallel parking. We further demonstrate on-chip manipulations including transporting, positioning, orientation, and sorting, with on-situ operation, high selectivity, and great versatility. Our work paves the way to realize full co-integration of various functionalized photonic components on single chips.

6.
J Mater Chem B ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33459325

RESUMO

To solve the high instances of failure caused by endodontic reinfection, herein, an improved root filling material was produced to meet the multi-functional demand of sealers for root canal therapy. In this study, polyurethane (PU)-based nanocomposites were prepared by loading bismuth oxide, hydroxyapatite and antibacterial agents, namely Ag3PO4 and ZnO nanoparticles, which were named CP-Ag and CP-Zn sealers, respectively. A parallel biological evaluation at bacterial and cellular levels was performed to determine the fate of the different components of the PU-based sealers. Furthermore, the composition of sealers was quantified by screening their antibacterial activity and apoptotic factors, considering the potential toxicity of the nanoparticles and high dosage of metals. The in vitro optimization investigation was conducted systematically against Streptococcus mutans and Staphylococcus aureus, including bacteriostatic and dynamic tests, and the expression of the B-cell lymphoma-2 gene family and caspase proteases in the mitochondria-mediated apoptotic pathway was evaluated using the commercial AH Plus® and Apexit® Plus sealers for comparison. Additionally, the physical properties and sealing ability of sealers were assessed. The results showed that all PU-based sealers could meet the requirements of ISO 6876:2012 for root canal sealing materials. Based on the evaluation system, CP-Zn sealers expressed longer lasting antibacterial activity and lower toxic effect on cells compared to CP-Ag sealers. Especially, the CP-Zn5 sealer exhibited selective antimicrobial efficacy and hypo-toxicity, which were better than that of the two commercial sealers. According to the two-dimensional and three-dimensional methods, the good sealing ability of the CP-Zn5 sealer is the same as the excellent filling characters of AH Plus, which adapts to irregular root canals.

7.
EJNMMI Phys ; 8(1): 3, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33411102

RESUMO

BACKGROUND: 99mTc-PYP scintigraphy provides differential diagnosis of ATTR cardiomyopathy (ATTR-CM) from light chain cardiac amyloidosis and other myocardial disorders without biopsy. This study was aimed to assess the diagnostic feasibility and the operator reproducibility of 99mTc-PYP quantitative SPECT. METHOD: Thirty-seven consecutive patients who underwent a 99mTc-PYP thorax planar scan followed by SPECT and CT scans to diagnose suspected ATTR-CM were enrolled. For the quantitative SPECT, phantom studies were initially performed to determine the image conversion factor (ICF) and partial volume correction (PVC) factor to recover 99mTc-PYP activity concentration in the myocardium for calculating the standardized uptake value (SUV) (unit: g/ml). SUVmax was compared among groups of ATTR-CM, AL cardiac amyloidosis, and other pathogens (others) and among categories of Perugini visual scores (grades 0-3). The intra- and inter-operator reproducibility of quantitative SPECT was verified, and the corresponded repeatability coefficient (RPC) was calculated. RESULTS: The ICF was 79,327 Bq/ml to convert count rate in pixel to 99mTc activity concentration. PVC factor as a function of the measured activity concentration ratio in the myocardium and blood-pool was [y = 1.424 × (1 - exp(- 0.759 × x)) + 0.104]. SUVmax of ATTR-CM (7.50 ± 2.68) was significantly higher than those of AL (1.96 ± 0.35) and others (2.00 ± 0.74) (all p < 0.05). SUVmax of grade 3 (8.95 ± 1.89) and grade 2 (4.71 ± 0.23) were also significantly higher than those of grade 1 (1.92 ± 0.31) and grade 0 (1.59 ± 0.39) (all p < 0.05). Correlation coefficient (R2) of SUVmax reached 0.966 to 0.978 with only small systematic difference (intra = - 0.14; inter = - 0.23) between two repeated measurements. Intra- and inter-operator RPCs were 0.688 and 0.877. CONCLUSIONS: 99mTc-PYP quantitative SPECT integrated with adjustable PVC factors is feasible to quantitatively and objectively assess the burden of cardiac amyloidosis for diagnosis of ATTR-CM.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33360415

RESUMO

Charge variants are the most commonly observed sources of heterogeneity in the routine manufacturing of monoclonal antibodies. To gain further insight into the structural foundation of charge heterogeneity and its influence on biological functions, an infliximab biosimilar HS626 from a biopharmaceutical facility was isolated by semipreparative cation exchange chromatography (CEX) to obtain fractions of acidic and basic charge variants and determine the main species. It was assessed again by CEX to ensure purities. Through a series of structural and physicochemical characterizations, we concluded that the acidic variants were caused by fragments, Met oxidation, Asn deamidation, higher levels of sialylation and galactosylation of N-linked glycans, and less high mannose. The basic variants resulted mainly from aggregates, fragments, and Met oxidation. Through further analysis of antigen binding affinity, cell death inhibitory activity, ADCC, and CDC, as well as FcRn, FcγRIIIa, and C1q affinity, we demonstrated that the charge heterogeneity did not affect biological functions. This research enhances the understanding of charge variants, which are usually effective components that should not be intentionally reduced unless biological functions are affected.

9.
Cardiovasc Pathol ; 50: 107286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32947039

RESUMO

BACKGROUND: Primary cardiac synovial sarcoma was an exceedingly rare tumor that less reported. The study investigated the clinicopathologic, immunohistochemical, and molecular features of primary cardiac synovial sarcoma. METHODS: A total of five cardiac synovial sarcoma cases were assessed and reviewed using H&E, immunohistochemical and fluorescence in situ hybridization staining methods. Clinicopathological data were retrospectively analyzed and followed up. RESULTS: The cases occurred in four males and one female ranging in age from 23 to 48 years (mean, 32 years). The tumors were grossly large and solid (7.4-13.7 cm; mean 8.6 cm). Microscopically, clinical cases were biphasic (n = 2) and monophasic (n = 3) types and were diffusely immunoreactive for EMA, vimentin, and BCL-2. All cases demonstrated SS18 rearrangement by fluorescence in situ hybridization staining. Clinically, three patients died within 1 year after surgery, while one patient had bone metastasis and still carried the disease. One last patient underwent a heart transplant and survived without evidence of the disease. CONCLUSION: Cardiac synovial sarcoma was an aggressive tumor whose differentiation may be a continuous and complex morphologic spectrum. SS18 rearrangement demonstration by fluorescence in situ hybridization was decisive in our study for differential diagnosis of cardiac synovial sarcoma and other tumors. Cardiac synovial sarcoma usually endured poor survival rates. Patients in advanced stages may undergo heart transplantation as a means of improving their survival rates.


Assuntos
Neoplasias Cardíacas , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Sarcoma Sinovial , Adulto , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Feminino , Rearranjo Gênico , Predisposição Genética para Doença , Neoplasias Cardíacas/química , Neoplasias Cardíacas/genética , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/cirurgia , Transplante de Coração , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Estudos Retrospectivos , Sarcoma Sinovial/química , Sarcoma Sinovial/genética , Sarcoma Sinovial/secundário , Sarcoma Sinovial/cirurgia , Resultado do Tratamento , Adulto Jovem
10.
J Chem Phys ; 153(20): 204704, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33261489

RESUMO

Oxygen vacancies are ubiquitous in TiO2 and play key roles in catalysis and magnetism applications. Despite being extensively investigated, the electronic structure of oxygen vacancies in TiO2 remains controversial both experimentally and theoretically. Here, we report a study of a neutral oxygen vacancy in TiO2 using state-of-the-art quantum chemical electronic structure methods. We find that the ground state is a color center singlet state in both the rutile and the anatase phases of TiO2. Specifically, embedded coupled cluster with singles, doubles, and perturbative triples calculations find, for an oxygen vacancy in rutile, that the lowest triplet state energy is 0.6 eV above the singlet state, and in anatase, the triplet state energy is higher by 1.4 eV. Our study provides fresh insights into the electronic structure of the oxygen vacancy in TiO2, clarifying earlier controversies and potentially inspiring future studies of defects with correlated wave function theories.

11.
Materials (Basel) ; 13(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266095

RESUMO

The vacuum hot-rolled SUS314/Q235 stainless steel clad plate has many drawbacks including serious interface alloy element diffusion, stainless steel cladding's sensitization, and carbon steel substrate's low strength. In this study, the comprehensive properties were systematically adjusted by changing the thickness of the Ni interlayer (0, 100, 200 µm) and the quenching temperature (1000~1150 °C). The results showed that the Ni interlayer can obviously hinder the diffusion of carbon element, so as to achieve the purpose of eliminating the decarburized layer and reducing the carbon content of the carburized layer. Meanwhile, the perfect metallurgical bonding between the substrate and cladding can be obtained, effectively improving the stainless steel clad plate's tensile shear strength and comprehensive mechanical properties, and significantly reduce the brittleness of the carburized layer. As the quenching temperature increases, the grains coarsening of carbon steel and stainless steel became more and more serious, and the sensitization phenomenon and the thickness of the carburized layer are gradually decreased. The stainless steel clad plate (Ni layer thickness of 100 µm) quenched at 1050 °C had the best comprehensive mechanical properties. Herein, the interface shear strength, tensile strength and the fracture elongation reached 360.5 MPa, 867 MPa and 16.10%, respectively, achieving strengthening and toughening aim. This is attributed to the disappearance of the sensitization phenomenon, the grain refinement and the lower interface residual stress.

12.
J Chem Theory Comput ; 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33351621

RESUMO

Semiclassical instanton theory is a form of quantum transition-state theory which can be applied to the computation of thermal reaction rates in complex molecular systems including quantum tunneling effects. There have been a number of attempts to extend the theory to treat microcanonical rates. However, the previous formulations are either computationally unfeasible for large systems due to an explicit sum over states or they involve extra approximations, which make them less reliable. We propose a robust and practical microcanonical formulation called density-of-states instanton theory, which avoids the sum over states altogether. In line with the semiclassical approximations inherent to the instanton approach, we employ the stationary-phase approximation to the inverse Laplace transform to obtain the densities of states. This can be evaluated using only post-processing of the data available from a small set of instanton calculations, such that our approach remains computationally efficient. We show that the new formulation predicts results that agree well with quantum scattering theory for an atom-diatom reaction and with experiments for a photoexcited unimolecular hydrogen transfer in a Criegee intermediate. When the thermal rate is evaluated from a Boltzmann average over our new microcanonical formalism, it can overcome some problems of conventional instanton theory. In particular, it predicts a smooth transition at the crossover temperature and is able to describe bimolecular reactions with pre-reactive complexes such as CH3OH + OH.

13.
Lab Chip ; 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33305767

RESUMO

Mobile microrobots that maneuver in liquid environments and navigate inside the human body have drawn a great interest due to their possibility for medical uses serving as an in vivo cargo. For this system, the effective self-propelling method, which should be powered wirelessly and controllable in 3-D space, is of paramount importance. This article describes a bubble-powered swimming microdrone that can navigate in 3-D space in a controlled manner. To enable 3-D propulsion with steering capability, air bubbles of three lengths are trapped in microtubes that are embedded and three-dimensionally aligned inside the drone body using two-photon polymerization. These bubbles can generate on-demand 3-D propulsion through microstreaming when they are selectively excited at their individual resonance frequencies that depend on the bubble sizes. In order to equip the drone with highly stable maneuverability, a non-uniform mass distribution of the drone body is carefully designed to spontaneously restore the drone to the upright position from disturbances. A mathematical model of the restoration mechanism is developed to predict the restoration behavior showing a good agreement with the experimental data. The present swimming microdrone potentially lends itself to a robust 3-D maneuverable microscale mobile cargo navigating in vitro and in vivo for biomedical applications.

14.
Brain Behav ; : e01933, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33300691

RESUMO

INTRODUCTION: Agenesis of the corpus callosum (AgCC) is characterized by the congenital partial or complete absence of the corpus callosum. Several strains of mice have been reported to carry AgCC, with the BTBR T+ Itpr3tf /J (BTBR) inbred mouse strain consistently showing a complete absence of the corpus callosum, as well as a variable reduction in the size of the hippocampal commissure. While much research has focused on the social deficits of the BTBR strain, little research on its cognitive behavior has been conducted. The goal of our study was to compare two facets of executive functioning, spatial working memory, and sustained attention between the BTBR and C57BL/6J (B6) strains. METHODS: Spatial working memory was measured utilizing a delayed matching-to-position (DMTP) task and sustained attention was measured utilizing an operant task in which mice were trained to distinguish signal and nonsignal events. RESULTS: Both the BTBR and B6 mice demonstrated a predictable decline in performance on the DMTP task as the delay interval increased and predictable increase in performance on the sustained attention task as the duration of the signal event increased. Although no significant differences were found between strains on the performance of these tasks, there was a significant difference in learning the association between lever pressing and food reward. Histological investigation confirmed the complete absence of commissural fibers from the corpus callosum, but also the hippocampal commissure, counter to a previous study. CONCLUSION: The results suggest spatial working memory and sustained attention are unaffected by the absence of these commissural fibers alone.

15.
Perit Dial Int ; : 896860820976983, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33272119

RESUMO

BACKGROUND: Gut microbiota alters in patients with end-stage renal disease, which contributes to inflammation, atherosclerosis, and results in increased incidence of cardiovascular diseases. The present study investigated the potential clinical factors, which influence the gut microbial structure and function in patients undergoing peritoneal dialysis (PD). METHODS: This is a cross-sectional study performed in 81 prevalent PD patients. Gut microbiota was assessed by high throughput sequencing of 16S ribosomal ribonucleic acid gene in fecal samples. Gas chromatography was conducted to measure stool short-chain fat acid (SCFA) concentrations. Demographic parameters and clinical characteristics, including dialysis regimen, residual renal function, nutrition, and inflammation, were retrieved and related to the properties of gut microbiota. RESULTS: PD duration, peritoneal glucose exposure, and estimated glomerulus filtration rate (eGFR) were identified to be associated with microbial variations. Significant separation of microbial composition was shown between patients with short or long PD duration (p = 0.015) and marginal differences were found between patients grouped by different levels of peritoneal glucose exposure (p = 0.056) or residual renal function (p = 0.063). A couple of gut bacteria showed different abundance at amplicon sequencing variant level between these patient groups (p < 0.05). In addition, stool isobutyric and isovaleric acid concentrations were significantly reduced in patients with longer dialysis duration, higher peritoneal glucose exposure, or declined eGFR (p < 0.05). CONCLUSIONS: This pilot study demonstrated that long dialysis duration, high peritoneal glucose exposure, and loss of residual renal function were associated with gut microbiota alteration and reduced branched-chain SCFA production in PD patients.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33258227

RESUMO

The hydrolysis of earth-abundant Al(III) has implications in mineral mimicry, geochemistry and environmental chemistry. The design and synthesis of third-order nonlinear optical (NLO) materials are important in modern chemistry due to their extensively optical applications. To study the hydrolysis and NLO properties, herein the assembly of Al(III) ions with π conjugated carboxylate ligands were carried out. As a result, a series of Al32-oxo clusters with hydrotalcite-like cores and π conjugated shells were isolated. Thanks to the accurate X-ray diffraction methods, the boundary hydrolysis snapshots that occur at equatorial unsaturated coordination sites of Al(III) ions are discovered. The charge distribution analysis and theoretical DFT calculations further supported proposed boundary substitution idea. Z-scan experiment results showed that the Al32-oxo clusters possess significant reverse saturable absorption (RSA) response with the minimal normalized transmittance up to 29%, indicating they are suitable candidates for optical limiting (OL) materials. This work is conducive to understanding the hydrolysis of Al(III) but also provides insight into the layered materials who also have strong boundary activity at the edges or corners.

17.
ACS Nano ; 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33316158

RESUMO

Highly active oxygen evolution reaction (OER) electrocatalysts are important to effectively transform renewable electricity to fuel and chemicals. In this work, we construct a series of multimetal oxide nanoplate OER electrocatalysts through successive cation exchange followed by electrochemical oxidation, whose electronic structure and diversified metal active sites can be engineered via the mutual synergy among multiple metal species. Among the examined multimetal oxide nanoplates, CoCeNiFeZnCuOx nanoplates exhibit the optimal adsorption energy of OER intermediates. Together with the high electrochemical active surface area, the CoCeNiFeZnCuOx nanoplates manage to deliver a small overpotential of 211 mV at an OER current density of 10 mA cm-2 (η10) with a Tafel slope as low as 21 mV dec-1 in 1 M KOH solution, superior to commercial IrO2 (339 mV at η10, Tafel slope of 55 mV dec-1), which can be stably operated at 10 mA cm-2 (at an overpotential of 211 mV) and 100 mA cm-2 (at an overpotential of 307 mV) for 100 h.

18.
Chemistry ; 2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33372312

RESUMO

In this work we employ electronic structure and non-adiabatic dynamics methods to explore excited-state properties of covalently bonded zinc phthalocyanine (ZnPc)-fullerene (C60) dyads with 6-6 [or 5-6] bonding configuration in which ZnPc is bonded to two carbon atoms shared by the two hexagonal rings [or a pentagonal and a hexagonal ring] in C60. In both cases, the locally excited (LE) states on ZnPc are spectroscopically bright. However, their different chemical bondings differentiate the electronic interactions between ZnPc and C60. In the 5-6 bonding configuration the LE states on ZnPc are much higher in energy than the LE states on C60. Thus, the excitation energy transfer from ZnPc to C60 is thermodynamically favorable. On the other hand, in the 6-6 bonding configuration such a process is inhibited because the LE states on ZnPc are the lowest ones. More detailed mechanisms are elucidated from non-adiabatic dynamics simulations. In the 6-6 bonding configuration, no excitation energy transfer has been observed. In contrast, in the 5-6 bonding configuration, several LE and charge-transfer (CT) excitons have been identified to participate in the energy transfer process. Further analysis reveals that the photoinduced energy transfer is mediated by a CT exciton, such that electron and hole transfer processes take place in a concerted but asynchronous manner in the excitation energy transfer. Furthermore, the present work opens up new avenues for regulating excited-state properties of molecular donor-acceptor dyads by means of chemical bonding.

19.
Front Microbiol ; 11: 570269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33224112

RESUMO

Ubiquitin is a highly conserved protein required for various fundamental cellular processes in eukaryotes. Herein, we first report the contribution of the ubiquitin fusion protein Ubi1 (a ubiquitin monomer fused with the ribosome protein L40e, Rpl40e) in the growth and pathogenicity of Cryptococcus neoformans. UBI1 deletion resulted in severe growth restriction of C. neoformans, whose growth rate was positively correlated with UBI1 expression level. The growth defect of the ubi1Δ strain could be closely associated with its morphological abnormalities, such as its reduced ribosome particles. In addition, the ubi1Δ mutant also displayed increased cell ploidy, cell cycle arrest, and decreased intracellular survival inside macrophages. All these phenotypes were reversed by the reconstitution of the full-length UBI1 gene or RPL40a domain. Mouse survival and fungal burden assays further revealed a severely attenuated pathogenicity for the ubi1Δ mutant, which is probably associated with its reduced stress tolerance and the induction of T-helper 1-type immune response. Taken together, Ubi1 is required for maintaining the vegetative growth, morphological homeostasis, cell cycle progression, and pathogenicity in vivo of C. neoformans. The pleiotropic roles of Ubi1 are dependent on the presence of Rpl40e and associated with its regulation of cryptococcal ribosome biogenesis.

20.
Preprint | medRxiv | ID: ppmedrxiv-20230656

RESUMO

Amperial is a novel assay platform that uses immobilized antigen in a conductive polymer gel followed by an electrochemical detection. A highly specific and sensitive assay was developed to quantify levels of IgG antibodies to SARS-CoV-2 in saliva. After establishing linearity and limit of detection we established a reference range of 5 standard deviations above the mean. There were no false positives in 667 consecutive saliva samples obtained prior to 2019. Saliva was obtained from 34 patients who had recovered from documented COVID-19 or had documented positive serologies. All of the patients with symptoms severe enough to seek medical attention had positive antibody tests and 88% overall had positive results. We obtained blinded paired saliva and plasma samples from 14 individuals. The plasma was analyzed using an EUA-FDA cleared ELISA kit and the saliva was analyzed by our Amperial assay. All 5 samples with negative plasma titers were negative in saliva testing. Eight of the 9 positive plasma samples were positive in saliva and 1 had borderline results. A CLIA validation was performed as a laboratory developed test in a high complexity laboratory. A quantitative non-invasive saliva based SARSCoV-2 antibody test was developed and validated with sufficient specificity to be useful for population-based monitoring and monitoring of individuals following vaccination.

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