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1.
Nano Lett ; 24(26): 8134-8142, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38900138

RESUMO

Developing highly efficient and carbon monoxide (CO)-tolerant platinum (Pt) catalysts for the formic acid oxidation reaction (FAOR) is vital for direct formic acid fuel cells (DFAFCs), yet it is challenging due to the high energy barrier of direct intermediates (HCOO* and COOH*) as well as the CO poisoning issues associated with Pt alloy catalysts. Here we present a versatile biphasic strategy by creating a hexagonal/cubic crystalline-phase-synergistic PtPb/C (h/c-PtPb/C) catalyst to tackle the aforementioned issues. Detailed investigations reveal that h/c-PtPb/C can simultaneously facilitate the adsorption of direct intermediates while inhibiting CO adsorption, thereby significantly improving the activation and CO spillover. As a result, h/c-PtPb/C showcases an outstanding FAOR activity of 8.1 A mgPt-1, which is 64.5 times higher than that of commercial Pt/C and significantly surpasses monophasic PtPb. Moreover, the h/c-PtPb/C-based membrane electrode assembly exhibits an exceptional peak power density of 258.7 mW cm-2 for practical DFAFC applications.

2.
Int Urogynecol J ; 35(3): 615-625, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38265454

RESUMO

INTRODUCTION AND HYPOTHESIS: We hypothesized that applying cervical suction and persistent tension can develop a novel and efficient rat model of pelvic organ prolapse. METHODS: Fifteen rats underwent pilot testing to optimize the protocol. Sixteen rats were subjected to pelvic organ prolapse induction by cervical suction and constant traction, while five rats served as controls. The pelvic organ prolapse rats were assessed by a Rat Pelvic Organ Prolapse Quantification system at different time points, and their diet, urine, and stool were monitored for 21 days. The pelvic organ prolapse rats were also evaluated for urinary incontinence, urinary retention, leak point pressure, and vaginal histopathology at 21 days after operation. RESULTS: This rat model demonstrated pelvic floor prolapse in anatomic level, as well as physiological variations (urine incontinence, urinary retention) and pathological changes (collagen fracture, decreased collagen density). CONCLUSIONS: This is the first establishment of the pelvic organ prolapse rat model with all compartment defects, which provides a valuable tool for elucidating pelvic organ prolapse mechanisms and evaluating potential interventions.


Assuntos
Prolapso de Órgão Pélvico , Incontinência Urinária por Estresse , Incontinência Urinária , Feminino , Animais , Ratos , Prolapso de Órgão Pélvico/complicações , Prolapso de Órgão Pélvico/cirurgia , Colo do Útero , Vagina , Colágeno , Incontinência Urinária por Estresse/cirurgia
3.
Small ; 19(38): e2208202, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37222629

RESUMO

Pursuing highly active and long-term stable ruthenium (Ru) based oxygen evolution reaction (OER) catalyst for water electrolysis under acidic conditions is of great significance yet a tremendous challenge to date. To solve the problem of serious Ru corrosion in an acid medium, the trace lattice sulfur (S) inserted RuO2 catalyst is prepared. The optimized catalyst (Ru/S NSs-400) has shown a record stability of 600 h for the solely containing Ru (iridium-free) nanomaterials. In the practical proton exchange membrane device, the Ru/S NSs-400 can even sustain more than 300 h without obvious decay at the high current density of 250 mA cm-2 . The detailed investigations reveal that S doping not only changes the electronic structure of Ru via forming RuS coordination for high adsorption of reaction intermediates but also stabilizes Ru from over-oxidation. This strategy is also effective for improving the stability of commercial Ru/C and homemade Ru-based nanoparticles. This work offers a highly effective strategy to design high-performance OER catalysts for water splitting and beyond.

4.
Eur J Pediatr ; 182(10): 4399-4406, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37480545

RESUMO

We aimed to investigate the predictive validity of monocyte to high-density lipoprotein cholesterol ratio (MHR) for coronary artery lesions (CALs) and intravenous immunoglobulin (IVIG) resistance in complete Kawasaki disease (KD). MHR values of a total of 207 complete KD patients were calculated and analyzed with regard to their clinical characteristics and outcomes. We compared the differences in clinical data and laboratory parameters between CAL+ group and CAL- group as well as between IVIG-resistant group and IVIG-responsive group. Spearman's correlation analysis was applied to evaluate the correlation between C-reactive protein (CRP) and MHR. Multivariate logistic regression was used to identify risk factors of CALs and IVIG resistance. Receiver operating characteristic (ROC) curve analysis was chosen to determine the optimal cut-off value of MHR and its validity in predicting CALs and IVIG resistance. The MHR level was significantly higher in the CAL+ group, with cut-off value of 1.30 g/L, yielding a sensitivity of 0.753 and specificity of 0.805, as well as in IVIG-resistant group, with cut-off value of 1.03 g/L, yielding a sensitivity of 0.97 and specificity of 0.485. Multivariate logistic regression showed that MHR was an independent risk factor for CALs but not for IVIG resistance. According to the Spearman's correlation analysis, CRP was positively correlated with the MHR. CONCLUSIONS: As a practical, cost-effective inflammatory biomarker, MHR has a significantly predictive value in complete KD children complicated with CALs and IVIG-resistance. Paying more attention to the changes of MHR in KD children may contribute to better understanding of KD development and prognosis in clinical practice. WHAT IS KNOWN: • CALs are the most prevalent serious sequela of KD, and approximately 10%~20% of patients do not respond to IVIG therapy. • MHR could be a convenient biomarker to predict the development and progression of CVDs. It has been reported that the MHR is a new prognostic biomarker in several CVDs. WHAT IS NEW: • MHR has a significantly predictive value in KD children complicated with CALs and IVIG-resistance. • Compared with the molecular and immunological biomarkers that have been reported, MHR has the characteristics of practical, cost-effective, higher sensitivity and specificity, which can be used as a predictive indicator in complete KD patients.


Assuntos
Doença da Artéria Coronariana , Síndrome de Linfonodos Mucocutâneos , Criança , Humanos , Lactente , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Monócitos/metabolismo , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Biomarcadores , Proteína C-Reativa/metabolismo , Estudos Retrospectivos
5.
Molecules ; 28(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37049767

RESUMO

The research on perylene diimide (PDI) aggregates effectively promotes their applications in organic photovoltaic solar cells and fluorescent sensors. In this paper, a PDI fabricated with three peripheral PDI units (N, N'-bis(6-undecyl) perylene-3,4,9,10-bis(dicarboximide)) is investigated. The trimer shows different absorption and fluorescence properties due to hydrophobicity when dissolved in the mixed solvent of tetrahydrofuran (THF) and water. Through comprehensive analysis of the fluorescence lifetime and transient absorption spectroscopic results, we concluded that the trimer underwent different excited state kinetic pathways with different concentrations of water in THF. When dissolved in pure THF solvent, both the intramolecular charge-transfer and excimer states are formed. When the water concentration increases from 0 to 50% (v/v), the formation time of the excimer state and its structural relaxation time are prolonged, illustrating the arising of the intermolecular excimer state. It is interesting to determine that the probability of the intramolecular charge-transfer pathway will first decrease and then increase as the speed of intermolecular excimer formation slows down. The two inflection points appear when the water concentration is above 10% and 40%. The results not only highlight the importance of hydrophobicity on the aggregate properties of PDI multimers but also guide the further design of PDI-based organic photovoltaic solar cells.

6.
Angew Chem Int Ed Engl ; 61(29): e202204423, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35419905

RESUMO

Chalcogenides have been viewed as important conversion-type Mg2+ -storage cathodes to fulfill the high volumetric energy density promise of magnesium (Mg) batteries. However, the low initial Columbic efficiency and the rapid capacity degradation remain challenges for the chalcogenide cathodes, as the clear Mg2+ -storage mechanism has yet to be clarified. Herein, we illustrate that the charge storage mechanism of the Cu2-x Se cathode is a reversible displacement reaction along with a polyselenide (PSe) mediated solution process of anion-compensation. The unique anion redox improves charge storage, while the dissolution of PSe also leads to performance degradation. To address this issue, we introduce Mo6 S8 into the Cu2-x Se cathode to immobilize PSe, which significantly improves performance, especially the reversible capacity (from 140 mAh g-1 to 220 mAh g-1 ). This work provides inspiration for the modification of the Mg2+ -storage cathode, which is a milestone for high-performance Mg batteries.

7.
Angew Chem Int Ed Engl ; 61(2): e202113086, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34664355

RESUMO

Solid-state zinc (Zn) batteries offer a new candidate for emerging applications sensitive to volume, safety and cost. However, current solid polymeric or ceramic electrolyte structures remain poorly conductive for the divalent Zn2+ , especially at room temperature. Constructing a heterogeneous interface which allows Zn2+ percolation is a viable option, but this is rarely involved in multivalent systems. Herein, we construct a solid Zn2+ -ion conductor by inducing crystallization of tailored eutectic liquids formed by organic Zn salts and bipolar ligands. High-entropy eutectic-networks weaken the ion-association and form interfacial Zn2+ -percolated channels on the nucleator surfaces, resulting in a solid crystal with exceptional selectivity for Zn2+ transport (t Zn 2 + =0.64) and appreciable Zn2+ conductivity (σ Zn 2 + =3.78×10-5  S cm-1 at 30 °C, over 2 orders of magnitude higher than conventional polymers), and finally enabling practical ambient-temperature Zn/V2 O5 metal solid cells. This design principle leveraged by the eutectic solidification affords new insights on the multivalent solid electrochemistry suffering from slow ion migration.

8.
J Interv Cardiol ; 2021: 1195613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35035305

RESUMO

OBJECTIVES: Minimally invasive coronary artery bypass grafting (MICS CABG) has emerged as an alternative treatment for patients with multi-vessel coronary artery disease, but there are certain surgical challenges inherent in the adoption of this approach. The present study was conducted to provide insight regarding the outcomes associated with our first 118 cases, to discuss the surgical difficulties encountered in these patients, and to outline the potential countermeasures. METHODS: Between January 2017 and January 2020, 118 patients underwent multi-vessel MICS CABG. These patients were stratified into two groups based upon whether they did or did not experience surgical challenges, and early clinical outcomes were compared between these groups to assess the incidence of technical difficulties and associated factors. RESULTS: Surgical challenges arose in 38 of the 118 cases in this study, including 13 cases of exposure-related difficulties, 11 cases of proximal anastomosis-related difficulties, 15 cases of distal anastomosis-related difficulties, 4 cases of LITA-related difficulties, and 3 cases of lung-related difficulties. Relative to the other 80 patients, those patients for whom intraoperative technical challenges arose experience significant increases in operative duration (4.94 ± 0.89 vs. 5.59 ± 1.11 h, P=0.001), intraoperative blood loss (667 ± 313 vs. 892 ± 532 mL, P=0.005), length of the ICU admission (17.59 ± 3.51 vs. 22.59 ± 17.31 h, P=0.015), and the duration of postoperative hospitalization (5.96 ± 1.23 vs. 6.71 ± 1.92 days, P=0.012). There were no significant differences between these groups with respect to the mean graft number, major complications such as stroke or organ dysfunction, or one-year graft patency. CONCLUSIONS: There is a substantial learning curve associated with performing off-pump MICS CABG to treat multi-vessel disease. Surgical challenges encountered during this procedure may increase the operative duration, intraoperative blood loss, ICU admission, and the duration of postoperative hospitalization. However, these issues do not appear to compromise the efficacy of complete revascularization, and early clinical outcomes associated with this procedure remain acceptable.


Assuntos
Doença da Artéria Coronariana , Procedimentos Cirúrgicos Minimamente Invasivos , Perda Sanguínea Cirúrgica , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Humanos , Resultado do Tratamento
9.
Phys Chem Chem Phys ; 23(41): 23961-23966, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34661215

RESUMO

This is the first study on a Ru(bda) (bda: 2,2'-bipyridine-6,6'-dicarboxylic acid) catalyst in solution using a home-built electrochemical cell, in combination with an energy-dispersive X-ray absorption spectroscopy setup. The oxidation state and coordination number of the catalyst during electrocatalysis could be estimated, while avoiding radiation damage from the X-rays.

10.
Echocardiography ; 38(5): 790-797, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33870543

RESUMO

The aim of this research was to compare the sensitivity and positive predictive value of contrast transcranial Doppler (c-TCD), contrast transthoracic echocardiography (c-TTE), and contrast transesophageal echocardiography (c-TEE), to determine the best method for diagnosing patent foramen ovale (PFO) and to provide a reference for the further improvement of clinical practice. We investigated 161 patients who suffered from migraines, cryptogenic stroke, TIA, and cerebral infarction of unknown cause. All patients underwent transcatheter examination, and the results of the right heart catheterization (RHC) were considered the gold standard for PFO diagnosis. The present study revealed that c-TTE with the Valsalva maneuver had a higher sensitivity in detecting PFO related right-to-left shunt (PFO-RLS), c-TCD performed similarly to c-TEE but maybe produce more false positives. Moreover, when we observed color shunt from the slit-like channel between the septum primum and the septum secundum on TEE, the positive predictive value was the highest. Patients with suspected PFO should be examined with c-TTE and c-TEE for confirmation. When there were a large number of bubbles in the left heart, especially in the presence of color shunt, the positive predictive value was the highest. The positive results of c-TCD only point out the presence of right-to-left shunt and cannot exclude extracardiac shunt, so c-TCD should not be used as a screen for PFO, additional measures such as c-TTE and c-TEE should be used.


Assuntos
Forame Oval Patente , Meios de Contraste , Ecocardiografia , Ecocardiografia Transesofagiana , Forame Oval Patente/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Ultrassonografia Doppler Transcraniana
11.
Pediatr Cardiol ; 42(5): 1141-1148, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33856498

RESUMO

Pulmonary artery hypertension (PAH) is a common and serious disease which is characterized by pulmonary vascular remodeling. Bosentan (BST) is the first approved oral targeted drug of endothelin-1 (ET-1) receptor antagonists for the treatment of PAH. MicroRNA-27a (miR-27a) and peroxisome proliferator-activated receptor γ (PPARγ) were found to be related to the pathogenesis of PAH. To further explore the signal transduction mechanism of BST in the treatment of PAH, we examined the effects of BST on endothelin receptors, miR-27a, and PPARγ. Meanwhile, the influence of miR-27a in the formation and development of PAH was discussed. Our results demonstrated that during the pathophysiology of PAH, miR-27a, PPARγ, and ET-1 were cross-inhibited, which indicated that the miR-27a/PPARγ/ET-1 signaling pathway was dysregulated; in addition, BST could competitively bind to ET-1 receptors and inhibit the miR-27a/PPARγ/ET-1 signaling pathway, thereby delaying the proliferation of PASMCs and affecting the development of PAH. Our results give a new understanding of the pathogenesis and treatment of PAH and provide more reliable evidence for the application of BST in the treatment of PAH in the clinic.


Assuntos
Bosentana/farmacologia , Antagonistas dos Receptores de Endotelina/farmacologia , PPAR gama/efeitos dos fármacos , Animais , Humanos , MicroRNAs/metabolismo , PPAR gama/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
12.
Phys Rev Lett ; 125(24): 245701, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33412026

RESUMO

The photoluminescence (PL) characterization spectrum has been widely used to study the electronic energy levels. Ho^{3+} is one of the commonly used doping elements to provide the PL with concentration limited to 1% atomic ratio. Here, we present a tricolor PL achieved in pyrochlore Ho_{2}Sn_{2}O_{7} through pressure treatment at room temperature, which makes a non-PL material to a strong multiband PL material with Ho^{3+} at the regular lattice site with 18.2% concentration. Under a high pressure compression-decompression treatment up to 78.0 GPa, the Ho_{2}Sn_{2}O_{7} undergoes pyrochlore (Fd 3m), to cotunnite (Pnma), then amorphous phase transition with different Ho^{3+} coordinations and site symmetries. The PL emerged from 31.2 GPa when the pyrochlore to cotunnite phase transition took place with the breakdown of site symmetry and enhanced hybridization of Ho^{3+} 4f and 5d orbitals. Upon decompression, the materials became an amorphous state with a partial retaining of the defected cotunnite phase, accompanied with a large enhancement of red-dominant tricolor PL from the ion pair cross-relaxation effect in the low-symmetry (C_{1}) site, in which two distinct Ho^{3+} emission centers (S center and L center) are present.

13.
Circ J ; 84(3): 436-444, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-31996489

RESUMO

BACKGROUND: This analysis compared short-term mortality, sternal wound infection (SWI), and long-term survival outcomes in diabetic patients who underwent coronary artery bypass grafting (CABG) with bilateral (BIMA) vs. single (SIMA) internal mammary artery, as well as in diabetic vs. non-diabetic patients undergoing BIMA grafting.Methods and Results:Nineteen studies were included in the study, covering 21,143 different patients. Of these patients, 6,464 underwent CABG with BIMA, 10,264 underwent CAGB with SIMA, 11,584 had diabetes, and 6,717 did not. Compared with SIMA, BIMA had a significantly lower risk of in-hospital mortality (odds ratio [OR] 0.73, P=0.02), but a significantly higher risk of SWI (OR 1.30, P=0.04). However, compared with non-diabetic patients who underwent CABG with BIMA, diabetic patients with BIMA grafting did not have significantly higher risks of either mortality (OR 1.22, P=0.53) or SWI (OR 1.10, P=0.72). No significant differences were detected with different harvesting techniques. Longer term, BIMA was associated with a significantly higher rate of survival than SIMA (hazard ratio [HR] 0.76, P<0.001). CONCLUSIONS: Results from the 2 types of comparisons indicate that BIMA is a preferable option for diabetic patients, even though it has a higher risk of infection. CABG with BIMA is also associated with a long-term survival benefit.


Assuntos
Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus/epidemiologia , Anastomose de Artéria Torácica Interna-Coronária , Tomada de Decisão Clínica , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/mortalidade , Mortalidade Hospitalar , Humanos , Anastomose de Artéria Torácica Interna-Coronária/efeitos adversos , Anastomose de Artéria Torácica Interna-Coronária/mortalidade , Medição de Risco , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento
14.
Angew Chem Int Ed Engl ; 59(28): 11477-11482, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32277864

RESUMO

Sluggish kinetics and poor reversibility of cathode chemistry is the major challenge for magnesium batteries to achieve high volumetric capacity. Introduction of the cuprous ion (Cu+ ) as a charge carrier can decouple the magnesiation related energy storage from the cathode electrochemistry. Cu+ is generated from a fast equilibrium between copper selenide electrode and Mg electrolyte during standing time, rather than in the electrochemical process. A reversible chemical magnesiation/de-magnesiation can be driven by this solid/liquid equilibrium. During a typical discharge process, Cu+ is reduced to Cu and drives the equilibrium to promote the magnesiation process. The reversible Cu to Cu+ redox promotes the recharge process. This novel Cu+ mediated cathode chemistry of Mg battery leads to a high reversible areal capacity of 12.5 mAh cm-2 with high mass loading (49.1 mg cm-2 ) of the electrode. 80 % capacity retention can be achieved for 200 cycles after a conditioning process.

15.
J Am Chem Soc ; 141(33): 13074-13080, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361482

RESUMO

Vacancy-ordered lead-free perovskites with more-stable crystalline structures have been intensively explored as the alternatives for resolving the toxic and long-term stability issues of lead halide perovskites (LHPs). The dispersive energy bands produced by the closely packed halide octahedral sublattice in these perovskites are meanwhile anticipated to facility the mobility of charge carriers. However, these perovskites suffer from unexpectedly poor charge carrier transport. To tackle this issue, we have employed the ultrafast, elemental-specific X-ray transient absorption (XTA) spectroscopy to directly probe the photoexcited electronic and structural dynamics of a prototypical vacancy-ordered lead-free perovskite (Cs3Bi2Br9). We have discovered that the photogenerated holes quickly self-trapped at Br centers, simultaneously distorting the local lattice structure, likely forming small polarons in the configuration of Vk center (Br2- dimer). More significantly, we have found a surprisingly long-lived, structural distorted state with a lifetime of ∼59 µs, which is ∼3 orders of magnitude slower than that of the charge carrier recombination. Such long-lived structural distortion may produce a transient "background" under continuous light illumination, influencing the charge carrier transport along the lattice framework.

17.
Cardiol Young ; 29(4): 462-466, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30957726

RESUMO

OBJECTIVES: The aim of this study was to evaluate the variant frequency of pulmonary arterial hypertension-related genes and provide theoretical basis for genetic screening of patients with pulmonary arterial hypertension further. METHODS: Ten genes associated with pulmonary arterial hypertension were sequenced in 7 cases of idiopathic pulmonary arterial hypertension and 34 cases of congenital heart disease (CHD) associated with pulmonary arterial hypertension by next-generation high-throughput sequencing. Function prediction and gene variant amino acid conservation were carried out by bioinformatics software. Family study was performed on the patients with the variant. RESULTS: A new bone morphogenetic protein receptor type 2(BMPR2) variant (c.344T>C, p. F115S) was discovered in a girl who was diagnosed with idiopathic pulmonary arterial hypertension. Her second aunt and third aunt carried the same variant and were confirmed as patients with pulmonary arterial hypertension as well. No variants or single nucleotide polymorphisms were found in other pulmonary arterial hypertension-associated genes. CONCLUSIONS: BMPR2 variant is the most common variant of pulmonary arterial hypertension. Genetic screening of BMPR2 variant and family survey in patients with pulmonary arterial hypertension is suggested for the sake of definite cause and better treatment.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Hipertensão Pulmonar Primária Familiar/genética , Cardiopatias Congênitas/genética , Adolescente , Criança , Pré-Escolar , Hipertensão Pulmonar Primária Familiar/complicações , Feminino , Predisposição Genética para Doença , Testes Genéticos , Cardiopatias Congênitas/complicações , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino
18.
J Phys Chem A ; 122(31): 6396-6406, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30052048

RESUMO

Photoinduced electronic and structural changes of a hydrogen-generating supramolecular RuPt photocatalyst are studied by a combination of time-resolved photoluminescence, optical transient absorption, and X-ray absorption spectroscopy. This work uses the element specificity of X-ray techniques to focus on the interplay between the photophysical and -chemical processes and the associated time scales at the catalytic Pt moiety. We observe very fast (<30 ps) photoreduction of the Pt catalytic site, followed by an ∼600 ps step into a strongly oxidized Pt center. The latter process is likely induced by oxidative addition of reactive iodine species. The oxidized Pt species is long-lived and fully recovers to the original ground state complex on a >10 µs time scale. However, the photosensitizing Ru moiety is fully restored on a much shorter ∼300 ns time scale. This reaction scheme implies that we may withdraw two electrons from a catalyst that is activated by a single photon.

19.
J Chem Phys ; 148(13): 134307, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626862

RESUMO

The photochemistry of halomethanes is fascinating for the complex cascade reactions toward either the parent or newly synthesized molecules. Here, we address the structural rearrangement of photodissociated CH2IBr in methanol and cyclohexane, probed by time-resolved X-ray scattering in liquid solution. Upon selective laser cleavage of the C-I bond, we follow the reaction cascade of the two geminate geometrical isomers, CH2I-Br and CH2Br-I. Both meta-stable isomers decay on different time scales, mediated by solvent interaction, toward the original parent molecule. We observe the internal rearrangement of CH2Br-I to CH2I-Br in cyclohexane by extending the time window up to 3 µs. We track the photoproduct kinetics of CH2Br-I in methanol solution where only one isomer is observed. The effect of the polarity of solvent on the geminate recombination pathways is discussed.

20.
Scand Cardiovasc J ; 52(5): 287-291, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30084275

RESUMO

OBJECTIVES: To investigate the association between promoter methylation of the TBX20 gene and tetralogy of Fallot (TOF). Methods. The methylation level of TBX20 promoter regions in 23 patients with TOF and five controls were analyzed through bisulfite sequencing polymerase chain reaction. Meanwhile, the expression of TBX20 mRNA was measured using real time fluorescence quantitative polymerase chain reaction. RESULTS: The region -400 to -48 in the TBX20 promoter consisting of 42 CpG sites was predicted to contain multiple transcription factor binding sites. In this study, the overall methylation level in this region was lower in patients with TOF than in the controls (P = .035). Among the 42 CpG sites, the methylation percentages of the CpG 26 site in the TOF cases were lower than those in the controls (P = .016). The mRNA expression of TBX20 in the right ventricular outflow tract myocardium was increased in TOF cases in contrast to those in the controls (P < .001). The methylation levels in TOF cases were correlated with mRNA expression values (r = -0.81, P < .001). CONCLUSION: The downregulated methylation level at TBX20 promoter may be responsible for the elevated mRNA expression levels in patients with TOF. The abnormal methylation status of the TBX20 promoter may contribute to the pathogenesis of TOF.


Assuntos
Metilação de DNA , Regiões Promotoras Genéticas , Proteínas com Domínio T/genética , Tetralogia de Fallot/genética , Estudos de Casos e Controles , Pré-Escolar , Ilhas de CpG , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Fenótipo , Fatores de Risco , Tetralogia de Fallot/diagnóstico por imagem
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