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1.
Pain Ther ; 2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33840060

RESUMO

INTRODUCTION: Postherpetic neuralgia (PHN) is the most common complication of herpes zoster. Methylene blue (MB) is an inhibitor of nitric oxide synthesis with potentially analgesic and anti-inflammatory properties. Studies have demonstrated that thoracic paravertebral single MB injection is effective in treating chronic pain. However, there are rare reports of the efficacy of continuous thoracic paravertebral infusion of MB for pain management in PHN patients. The purpose of this study was to evaluate the therapeutic effects of continuous thoracic paravertebral infusion of MB on PHN. METHODS: A total of 104 PHN patients were randomly divided into two groups: the control group (continuous thoracic paravertebral infusion of 5% lidocaine in a total volume of 300 ml) and the MB group (continuous thoracic paravertebral infusion of 5% lidocaine plus 0.2% MB in a total volume of 300 ml). All patients were evaluated using the Numerical Rating Scale (NRS), Insomnia Severity Index (ISI), Patient Health Questionnaire-9 (PHQ-9), 36-Item Short-Form Health Survey (SF-36), and medication doses before and after the procedure. The effective treatment rate and adverse complications were recorded 6 months after the procedure. RESULTS: In both groups, the NRS scores, ISI scores, PHQ-9 scores, and rescue medication dosages were significantly decreased at different time points after treatment compared to baseline, while the SF-36 scores were evidently improved at different time points after treatment compared to baseline. Compared with the control group, the MB group had significantly reduced NRS scores, ISI scores, PHQ-9 scores, and rescue medication dosages at each observation time point. Furthermore, the SF-36 scores in the MB group were significantly higher than those in the control group at each observation time point. The total effective treatment rate of the MB group was higher than that of the control group 6 months after the procedure. No severe adverse complications were observed in either group. CONCLUSIONS: Ultrasound-guided continuous thoracic paravertebral infusion with MB is a safe and effective therapy for PHN. Continuous infusion with MB can significantly reduce pain intensity, improve pain-related depression, increase quality of life, and decrease the amount of rescue medicine with no serious adverse complications.

2.
Adv Mater ; : e2100474, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33914352

RESUMO

Side-chain engineering has been an effective strategy in tuning electronic energy levels, intermolecular interaction, and aggregation morphology of organic photovoltaic materials, which is very important for improving the power conversion efficiency (PCE) of organic solar cells (OSCs). In this work, two D-A copolymers, PBQ5 and PBQ6, are designed and synthesized based on bithienyl-benzodithiophene (BDTT) as the donor (D) unit, difluoroquinoxaline (DFQ) with different side chains as the acceptor (A) unit, and thiophene as the π-bridges. PBQ6 with two alkyl-substituted fluorothiophene side chains on the DFQ units possesses redshifted absorption, stronger intermolecular interaction, and higher hole mobility than PBQ5 with two alkyl side chains on the DFQ units. The blend film of the PBQ6 donor with the Y6 acceptor shows higher and balanced hole/electron mobilities, less charge carrier recombination, and more favorable aggregation morphology. Therefore, the OSC based on PBQ6:Y6 achieves a PCE as high as 17.62% with a high fill factor of 77.91%, which is significantly higher than the PCE (15.55%) of the PBQ5:Y6-based OSC. The PCE of 17.62% is by far one of the highest efficiencies for the binary OSCs with polymer donor and Y6 acceptor.

3.
Adv Healthc Mater ; : e2100194, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33930258

RESUMO

The global cost of diabetes care exceeds $1 trillion each year with more than $327 billion being spent in the United States alone. Despite some of the advances in diabetes care including continuous glucose monitoring systems and insulin pumps, the technology associated with managing diabetes has largely remained unchanged over the past several decades. With the rise of wearable electronics and novel functional materials, the field is well-poised for the next generation of closed-loop diabetes care. Wearable glucose sensors implanted within diverse platforms including skin or on-tooth tattoos, skin-mounted patches, eyeglasses, contact lenses, fabrics, mouthguards, and pacifiers have enabled noninvasive, unobtrusive, and real-time analysis of glucose excursions in ambulatory care settings. These wearable glucose sensors can be integrated with implantable drug delivery systems, including an insulin pump, glucose responsive insulin release implant, and islets transplantation, to form self-regulating closed-loop systems. This review article encompasses the emerging trends and latest innovations of wearable glucose monitoring and implantable insulin delivery technologies for diabetes management with a focus on their advanced materials and construction. Perspectives on the current unmet challenges of these strategies are also discussed to motivate future technological development toward improved patient care in diabetes management.

4.
Free Radic Biol Med ; 165: 219-228, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33539948

RESUMO

Lipopolysaccharide (LPS) has been known to cause alveolar epithelial cell (AEC) apoptosis and barrier breakdown that characterize acute lung injury (ALI) and acute respiratory distress syndrome. We aimed to investigate whether mitoquinone (MitoQ), a mitochondria-targeted antioxidant, could alleviate LPS-induced AEC damage in ALI and its underlying mechanisms. In vitro studies in AEC A549 cell line, we noted that LPS could induce dynamin-related protein 1 (Drp1)-mediated mitochondrial fission, AEC apoptosis and barrier breakdown, which could be reversed with MitoQ and mitochondrial division inhibitor 1 treatment. Moreover, the protective role of MitoQ was attenuated with Drp1 overexpression. Nuclear factor E2-related factor 2 (Nrf2) downregulation could block the effect of MitoQ by decreasing the expression of Nrf2 target genes in LPS-treated AEC, such as heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1). Nrf2 gene knockdown in LPS-treated A549 cells prevented the protective effect of MitoQ from decreasing Drp1-mediated mitochondrial fission, AEC apoptosis and barrier breakdown. The lung protective effect of MitoQ by regulating the Drp1-mediated mitochondrial fission, AEC apoptosis and barrier breakdown was further confirmed in vivo with LPS-induced ALI mouse model. Additionally, the protective effect of MitoQ was inhibited by Nrf2 inhibitor ML385. We therefore conclude that MitoQ exerts ALI-protective effects by preventing Nrf2/Drp1-mediated mitochondrial fission, AEC apoptosis as well as barrier breakdown.

5.
Nat Commun ; 12(1): 178, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420010

RESUMO

Tandem organic solar cells are based on the device structure monolithically connecting two solar cells to broaden overall absorption spectrum and utilize the photon energy more efficiently. Herein, we demonstrate a simple strategy of inserting a double bond between the central core and end groups of the small molecule acceptor Y6 to extend its conjugation length and absorption range. As a result, a new narrow bandgap acceptor BTPV-4F was synthesized with an optical bandgap of 1.21 eV. The single-junction devices based on BTPV-4F as acceptor achieved a power conversion efficiency of over 13.4% with a high short-circuit current density of 28.9 mA cm-2. With adopting BTPV-4F as the rear cell acceptor material, the resulting tandem devices reached a high power conversion efficiency of over 16.4% with good photostability. The results indicate that BTPV-4F is an efficient infrared-absorbing narrow bandgap acceptor and has great potential to be applied into tandem organic solar cells.

6.
J Phys Chem A ; 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33449684

RESUMO

Quantum coherence effects on charge transfer and spin dynamics in a system having two degenerate electron acceptors are studied using a zinc 5,10,15-tri(n-pentyl)-20-phenylporphyrin (ZnP) electron donor covalently linked to either one or two naphthalene-1,8:4,5-bis(dicarboximide) (NDI) electron acceptors using an anthracene (An) spacer, ZnP-An-NDI (1) and ZnP-An-NDI2 (2), respectively. Following photoexcitation of 1 and 2 in toluene at 295 K, femtosecond transient absorption spectroscopy shows that the electron transfer (ET) rate constant for 2 is about three times larger than that of 1, which can be accounted for by the statistical nature of incoherent ET as well as the electron couplings for the charge separation reactions. In contrast, the rate constant for charge recombination (CR) of 1 is about 25% faster than that of 2. Using femtosecond transient infrared spectroscopy and theoretical analysis, we find that the electron on NDI2•- in 2 localizes onto one of the two NDIs prior to CR, thus precluding electronically coherent CR from NDI2•-. Conversely, CR in both 1 and 2 is spin coherent as indicated by the observation of a resonance in the 3*ZnP yield following CR as a function of applied magnetic field, giving spin-spin exchange interaction energies of 2J = 210 and 236 mT, respectively, where the line width of the resonance for 2 is greater than 1. These data show that while CR is a spin-coherent process, incoherent hopping of the electron between the two NDIs in 2, consistent with the lack of delocalization noted above, results in greater spin decoherence in 2 relative to 1.

7.
J Clin Gastroenterol ; 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33471487

RESUMO

AIMS OF THIS STUDY: A randomized clinical trial was undertaken to investigate the efficacy of acupoint catgut embedding (ACE) as adjunctive therapy to tauroursodeoxycholic acid (TUDCA) therapy on gallbladder emptying and clinical symptoms in patients with gallstone disease. MATERIALS AND METHODS: Between August 2018 and January 2019, 70 patients with gallstones in our hospital were enrolled in this prospective clinical trial. All the patients were randomly divided into the ACE group (ACE+TUDCA treatment for 8 wk) and the Sham group (Sham ACE+TUDCA treatment for 8 wk). In the ACE group, all the patients were nightly given ACE every 2 weeks, and in 2 groups, every patient took TUDCA 500 mg at bedtime. The parameters about gallbladder emptying were detected by ultrasound before and after the treatment, and the clinical symptom scores were recorded at the same time points. RESULTS: A total of 63 patients with gallstone disease were included in our study, with 33 patients in the ACE group and 30 patients in the Sham group. In the ACE group, the empty volume (EV) and gallbladder ejection fraction (GBEF) were improved after treatment (P<0.05). Almost every symptom score (except symptom 7, P=0.15) and total score were decreased (P<0.05). In the Sham group, the symptom 1, 2, 4, 5 scores, and total score were significantly decreased (P<0.05). Moreover, the residual volume in the ACE group was significantly lower than in the Sham group (P=0.008). The EV and GBEF in the ACE group were higher than that in the Sham group (P<0.05). The score of symptom 6 in the ACE group was lower than that in the Sham group (P=0.008). CONCLUSION: ACE therapy could more effectively improve the gallbladder emptying with a shorter treatment course. Therefore, ACE+TUDCA therapy might be a time-saving treatment for gallstones.

8.
Food Chem ; 338: 128119, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091976

RESUMO

The inhibition of the α-amylase and α-glucosidase activity facilitates the maintenance of circulating glucose levels by decreasing the rate of blood sugar absorption. Existing enzyme inhibitors such as acarbose, miglitol, and voglibose are used for inhibiting the activity of these enzymes, however, alternative solutions are required to avoid the side-effects of using these drugs. The current study aims to review recent evidence regarding the in vitro α-amylase and α-glucosidase inhibition activities of extracts derived from selected fruit, vegetables, and mushrooms. The mechanisms of action of the extracts involved in the inhibition of both enzymes are also presented and discussed. Compounds including flavonoids, phenolic acids, anthocyanins, saponins, carotenoids, terpenes, sugars, proteins, capsaicinoids, fatty acids, alkaloids have been shown to have α-amylase and α-glucosidase inhibition activities. Harvesting period, maturity stage, sample preparation, extraction technique, and solvent type are parameters that affect the α-amylase and α-glucosidase inhibition activities of the extracts.


Assuntos
Agaricales/química , Frutas/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Extratos Vegetais/farmacologia , Verduras/química , alfa-Amilases/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Extratos Vegetais/isolamento & purificação
9.
J Pain Res ; 13: 1747-1756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765049

RESUMO

Purpose: The causative mechanisms triggering myofascial pain syndrome (MPS) are still in debate. It is becoming evident that mitochondrial dysfunction may regulate pathways controlling MPS. The aim of this study was to investigate whether AMPK-PGC-1α-SIRT3 axis is associated with depression of mitochondrial function in the rat MPS model. Methods: A total of 32 Sprague-Dawley rats were randomly divided into control group and experimental group. The expression level of mRNA and protein of gastrocnemius medialis (GM) was analyzed by Western blot and RT-PCR. The histopathological findings were investigated through electron microscopes in GM of all groups. Results: Our results showed that MPS induces continuous depression of mitochondrial biogenesis and function via down-regulation of PGC-1α-SIRT3 axis accompanying with ATP fuel crisis as compared to control group. However, the expression level of SIRT3 mRNA did not change. Additionally, a correlated reduction of the mRNA and protein expression level of NRF-1 and TFAM, known as the downstream target of PGC-1α, suggesting further transcription of nuclear genes encoding mitochondria functional proteins for promoting mitochondria proliferation, oxidative phosphorylation and energy production is continuously depressed. Furthermore, phosphorylation extent of AMPK is also declined following MPS, and it is negatively correlated with reduction of ATP generation, suggesting that the complex network involves different inhibition in transcription, post-translational modification and a plethora of other effectors that mediate the inhibition roles. Conclusion: We here suggested that the down-regulation in AMPK-PGC-1α-SIRT3 axis network may be the basis for the association between mitochondrial dysfunction and MPS, where a vicious circle further aggravates the disease symptoms with ongoing ATP energy crisis.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32427404

RESUMO

Demonstrated in this work is a simple random ternary copolymerization strategy to synthesize a series of polymer acceptors, PTPBT-ETx , by polymerizing a small-molecule acceptor unit modified from Y6 with a thiophene connecting unit and a controlled amount of an 3-ethylesterthiophene (ET) unit. Compared to PTPBT of only Y6-like units and thiophene units, PTPBT-ETx (where x represents the molar ratio of the ET unit) with an incorporated ET unit in the ternary copolymers show up-shifted LUMO energy levels, increased electron mobilities, and improved blend morphologies in the blend film with the polymer donor PBDB-T. And the all-polymer solar cell (all-PSC) based on PBDB-T:PTPBT-ET0.3 achieved a high power conversion efficiency over 12.5 %. In addition, the PTPBT-ET0.3 -based all-PSC also exhibits long-term photostability over 300 hours.

11.
Dalton Trans ; 49(18): 6119-6126, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32323683

RESUMO

Owing to their environmentally friendly characteristic, InP-based quantum dots (QDs) show great potential in various fields as an alternative to Cd-based QDs. However, the current mainstream synthesis process, the (TMS)3P-based injection method, still faces many challenges, such as the high cost of (TMS)3P and complex temperature control. In contrast, the solvothermal method is considered to be more feasible and reproducible. Despite its potential advantages, little has been done to understand how the precursors influence the synthesis of InP QDs using the solvothermal method. In this research, InZnP/ZnS QDs were synthesized using practical phosphorus precursors (DEA)3P or (DMA)3P. Through the feasible regulation of zinc, indium, phosphorus and sulfur precursors, the band gap of the QDs could be widely and accurately tuned, and a much wider photoluminescence wavelength ranging from 484 nm to 651 nm could be achieved. Furthermore, InI3 and InBr3 contributed to the blueshift in the PL wavelengths, and the combination of (DEA)3P, (DMA)3P, n-DDT and t-DDT refined the PL wavelength with a small tuning gap of 5 nm.

12.
J Am Chem Soc ; 142(10): 4916-4924, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32069027

RESUMO

The torsional dependence of the ground state magnetic exchange coupling (J) and the corresponding electronic coupling matrix element (HDA) for eight transition metal complexes possessing donor-acceptor (D-A) biradical ligands is presented. These biradical ligands are composed of an S = 1/2 metal semiquinone (SQ) donor and an S = 1/2 nitronylnitroxide (NN) acceptor, which are coupled to each other via para-phenylene, methyl-substituted para-phenylenes, or a bicyclo[2.2.2]octane ring. The observed trends in electronic absorption and resonance Raman spectral features are in accord with a reduction in electronic and magnetic coupling between D and A units within the framework of our valence bond configuration interaction model. Moreover, our spectroscopic results highlight different orbital mechanisms that modulate coupling in these complexes, which is not manifest in the ferromagnetic JSQ-B-NN values. The work provides new detailed insight into the effects of torsional rotations which contribute to inhomogeneities in experimentally determined exchange couplings, electron transfer rates, and electron transport conductance measurements.

13.
J Am Chem Soc ; 142(7): 3346-3350, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32009396

RESUMO

Photoinduced electron transfer can produce radical pairs having two quantum entangled electron spins that can act as spin qubits in quantum information applications. Manipulation of these spin qubits requires selective addressing of each spin using microwave pulses. In this work, photogenerated spin qubit pairs are prepared within chromophore-modified DNA hairpins with varying spin qubit distances, and are probed using transient EPR spectroscopy. By performing pulse-EPR measurements on the shortest hairpin, selective addressing of each spin qubit comprising the pair is demonstrated. Furthermore, these spin qubit pairs have coherence times of more than 4 µs, which provides a comfortable time window for performing complex spin manipulations for quantum information applications. The applicability of these DNA-based photogenerated two-qubit systems is discussed in the context of quantum gate operations, specifically the controlled-NOT gate.


Assuntos
DNA/química , Radicais Livres/química , Sequências Repetidas Invertidas/efeitos da radiação , DNA/genética , DNA/efeitos da radiação , Radicais Livres/efeitos da radiação , Luz , Modelos Químicos , Teoria Quântica
14.
J Chem Phys ; 152(1): 014503, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31914753

RESUMO

Implementation of the two-qubit controlled-NOT (CNOT) gate is necessary to develop a complete set of universal gates for quantum computing. Here, we demonstrate that a photogenerated radical (spin qubit) pair within a covalent donor-chromophore-acceptor molecule can be used to successfully execute a CNOT gate with high fidelity. The donor is tetrathiafulvalene (TTF), the chromophore is 8-aminonaphthalene-1,8-dicarboximide (ANI), and the acceptor is pyromellitimide (PI). Selective photoexcitation of ANI with a 416 nm laser pulse results in subnanosecond formation of the TTF•+-ANI-PI•- radical (spin qubit) pair at 85 K having a 1.8 µs phase memory time. This is sufficiently long to execute a CNOT gate using a sequence of five microwave pulses followed by a sequence of two pulses that read out all the elements of the density matrix. Comparing these data to a simulation of the data that assumes ideal conditions results in a fidelity of 0.97 for the execution of the CNOT gate. These results show that photogenerated molecular spin qubit pairs can be used to execute this essential quantum gate at modest temperatures, which affords the possibility that chemical synthesis can be used to develop structures to execute more complex quantum logic operations using electron spins.

15.
Spinal Cord ; 58(3): 341-347, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31586154

RESUMO

STUDY DESIGN: A multicentre retrospective study. OBJECTIVE: A multicentre retrospective study was performed to observe the changes in serum cystatin C (CysC) levels in patients with acute spinal cord injury (SCI). SETTING: Four hospitals in China. METHODS: Over a 5-year study period, the CysC, creatinine (Cr), and blood urea nitrogen (BUN) levels of people who had incurred SCI in the preceding 7 days were collected and compared with those of people with limb fracture (LF) who were matched for injury time and gender. People with SCI also were grouped by injury duration, ASIA Impairment Scale (AIS) grade and the presence or absence of steroid therapy and compared each day. RESULTS: Three hundred and twenty-three samples from people with SCI were retrospectively collected; their mean serum CysC levels were significantly higher than those of people with LF (p < 0.001); No significant difference was observed in Cr or BUN levels between the two groups (p > 0.14). CysC levels increased on the second day, peaked on day 3, and returned to normal on day 5. The more severely injured individuals had higher CysC levels. Steroid therapy or not had no influence for CysC levels. CONCLUSION: CysC levels are increased in patients with acute SCI, possibly as a direct result of injury. Serum CysC is a potential biomarker of SCI.

16.
Cancer Gene Ther ; 27(10-11): 773-784, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31831855

RESUMO

Myogenic differentiation 1 (MyoD1) is a transcription factor that promotes expression of muscle-specific genes. MyoD1 is expressed at significantly lower levels in gastric cancer (GC) tissues and cells, and it induces apoptosis in GC cells. However, functions for MyoD1 in GC cell migration and gene expression have not been documented. We show that knockdown of MyoD1 promoted migration and invasion of GC cells, whereas MyoD1 overexpression suppressed migration and invasion. We performed chromatin immunoprecipitation (ChIP)-sequencing to identify MyoD1 target genes in MKN-45 cells. The 2-kb upstream regions (Up2k) of the transcription start sites of 57 genes were probably bound by MyoD1. Six of these genes function in signaling pathways such as synthesis of glycosphingolipid biosynthesis-lacto and neolacto series. MyoD1 inhibited transcription of fucosyltransferase IV (FUT4) by binding directly to the FUT4 F3; this finding was validated by ChIP-quantitative PCR and a luciferase reporter assay. Ulex europaeus agglutinin I, which binds Fucα1-2Galß1-4GlcNAc, and Lewis antigens showed decreased binding to the plasma membrane of cells that overexpressed MyoD1. Knockdown of FUT4 mimicked MyoD1 overexpression by suppressing GC cell migration and invasion; this result implied that MyoD1 suppressed cell migration and invasion via inhibiting the FUT4/matrix metallopeptidase signaling pathway. In summary, this study demonstrated that MyoD1 suppresses migration and invasion of GC cells by directly binding to the F3 region in the FUT4 Up2k and inhibiting FUT4/type II Lewis antigen expression.

17.
Polymers (Basel) ; 11(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810357

RESUMO

Polymer microspheres (PMs) are used as a new material to recover residual oil left in unswept oil areas after secondary recovery methods. The fact that the PMs plug the macropores causes the flow direction of the injection fluid to be transferred from macropores to micropores. In order to investigate the plugging and profile control mechanisms of PMs in reservoirs, four kinds of PMs with different particle sizes and four kinds of artificial cores with different permeability were selected for flooding tests, including plugging experiments and profile control experiments. The pore throat size distribution of cores was characterized by nuclear magnetic resonance (NMR) technology. The particle size distribution of PMs used in the experiment was characterized using a laser particle size analyzer. The results showed that there are six matching relationships existing simultaneously between pore throats and PMs based on theoretical analysis, which are completely plugging, single plugging, bridge plugging, smooth passing, deposition, and deformable passing. A key principle for optimizing PMs in profile control is that the particle size of the selected PMs can enter the high permeability layer well, but it is difficult for it to enter the low permeability layer. The results of this paper provide a theoretical basis for the optimal particle size of PMs during the oil field profile control process.

18.
J Am Chem Soc ; 141(31): 12236-12239, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31302997

RESUMO

When a molecular electron donor interacts with multiple electron acceptors, quantum coherence can enhance the electron transfer (ET) rate. Here we report photodriven ET rates in a pair of donor-acceptor (D-A) compounds that link one anthracene (An) donor to one or two equivalent 1,4-benzoquinone (BQ) acceptors. Subpicosecond ET from the lowest excited singlet state of An to two BQs is about 2.4 times faster than ET to one BQ at room temperature, but about 5 times faster at cryogenic temperatures. This factor of 2 increase results from a transition from ET to one of two acceptors at room temperature to ET to a superposition state of the two acceptors with correlated system-bath fluctuations at low temperature.

19.
Faraday Discuss ; 216(0): 319-338, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31066389

RESUMO

Coherent interactions are prevalent in photodriven processes, ranging from photosynthetic energy transfer to superexchange-mediated electron transfer, resulting in numerous studies aimed towards identifying and understanding these interactions. A key motivator of this interest is the non-statistical scaling laws that result from coherently traversing multiple pathways due to quantum interference. To that end, we employed ultrafast transient absorption spectroscopy to measure electron transfer in two donor-acceptor molecular systems comprising a p-(9-anthryl)-N,N-dimethylaniline chromophore/electron donor and either one or two equivalent naphthalene-1,8:4,5-bis(dicarboximide) electron acceptors at both ambient and cryogenic temperatures. The two-acceptor compound shows a statistical factor of 2.1 ± 0.2 rate enhancement at room temperature and a non-statistical factor of 2.6 ± 0.2 rate enhancement at cryogenic temperatures, suggesting correlated interactions between the two acceptors with the donor and with the bath modes. Comparing the charge recombination rates indicates that the electron is delocalized over both acceptors at low temperature but localized on a single acceptor at room temperature. These results highlight the importance of shielding the system from bath fluctuations to preserve and ultimately exploit the coherent interactions.

20.
BMC Nephrol ; 20(1): 34, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30709342

RESUMO

BACKGROUND: Globally, there is increased clinical interest and uptake of hemodiafiltration (HDF) for increased removal of uremic toxins. To date, there has been no epidemiological analysis of HDF in China. We present HDF practice patterns and associated mortality risk in Shanghai. METHODS: This is an observational, prospectively collected, retrospective analysis of 9351 Chinese patients initiating hemodialysis in Shanghai from 2007 to 2014. The primary exposure was hemodialysis sub-modality at inception, classified into hemodiafiltration (HDF) and hemodialysis (HD), with adjustment for concommitant hemoperfusion. The primary outcome was patient mortality. We used Cox proportional hazards regression and Fine and Gray's proportional subhazards regression, with multiple imputation of missing co-variates by the chained equation method, adjusting for demographic and clinical variables. RESULTS: Overall, patients in the cohort were younger, with a more males, and with a lower body mass index when compared to corresponding non-Asian cohorts. Mortality rate was low although it doubled over the period of observation. HDF utilization increased from 7% of patients in 2007 to 42% of patients in 2014. The majority of patients received HDF once a week. The adjusted hazard ratio of death (95% confidence intervals) for HDF versus HD was 0.85 (0.71-1.03), and corresponding sub-hazard ratio 0.86 (0.71-1.03). There was strong effect modification by age. In those aged 40-60 years, the hazard ratio (95% confidence intervals) was 0.65 (0.45-0.94), and sub-hazard ratio also 0.65 (0.45-0.95). CONCLUSIONS: Our study has certain limitations resulting from the limited number of co-variates available for modelling, missing data for some co-variates, and the lack of verification of data against source documentation. Notwithstanding, there is evidence of clinical benefit from HDF in China, and potential to improve patient outcomes through the greater removal of middle and larger uremic solutes.


Assuntos
Hemodiafiltração/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Distribuição por Idade , Idoso , Tamanho Corporal , China , Feminino , Hemodiafiltração/métodos , Humanos , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Utilização de Procedimentos e Técnicas/estatística & dados numéricos , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Albumina Sérica/análise , Distribuição por Sexo , Resultado do Tratamento
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