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1.
Dalton Trans ; 53(17): 7303-7314, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38587832

RESUMO

The construction of sulfur-incorporated cluster-based coordination polymers was limited and underexplored due to the lack of efficient synthetic routes. Herein, we report facile mechanochemical ways toward a new series of SFe3(CO)9-based dipyridyl-Cu polymers by three-component reactions of [Et4N]2[SFe3(CO)9] ([Et4N]2[1]) and [Cu(MeCN)4][BF4] with conjugated or conjugation-interrupted dipyridyl ligands, 1,2-bis(4-pyridyl)ethylene (bpee), 1,2-bis(4-pyridyl)ethane (bpea), 4,4'-dipyridyl (dpy), or 1,3-bis(4-pyridyl)propane (bpp), respectively. X-ray analysis showed that bpee-containing 2D polymers demonstrated unique SFe3(CO)9 cluster-armed and cluster-one-armed coordination modes via the hypervalent µ5-S atom. These S-Fe-Cu polymers could undergo flexible structural transformations with the change of cluster bonding modes by grinding with stoichiometric amounts of dipyridyls or 1/[Cu(MeCN)4]+. They exhibited semiconducting behaviors with low energy gaps of 1.55-1.79 eV and good electrical conductivities of 3.26 × 10-8-1.48 × 10-6 S cm-1, tuned by the SFe3(CO)9 cluster bonding modes accompanied by secondary interactions in the solid state. The electron transport efficiency of these polymers was further elucidated by solid-state packing, X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES), density of states (DOS), and crystal orbital Hamilton population (COHP) analysis. Finally, the solid-state electrochemistry of these polymers demonstrated redox-active behaviors with cathodically-shifted patterns compared to that of [Et4N]2[1], showing that their efficient electron communication was effectively enhanced by introducing 1 and dipyridyls as hybrid ligands into Cu+-containing networks.

2.
Nat Commun ; 14(1): 7153, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935667

RESUMO

Inaccessibility of stored memory in ensemble cells through the forgetting process causes animals to be unable to respond to natural recalling cues. While accumulating evidence has demonstrated that reactivating memory-stored cells can switch cells from an inaccessible state to an accessible form and lead to recall of previously learned information, the underlying cellular and molecular mechanisms remain elusive. The current study used Drosophila as a model to demonstrate that the memory of one-trial aversive olfactory conditioning, although inaccessible within a few hours after learning, is stored in KCαß and retrievable after mild retraining. One-trial aversive conditioning triggers protein synthesis to form a long-lasting cellular memory trace, approximately 20 days, via creb in KCαß, and a transient cellular memory trace, approximately one day, via orb in MBON-α3. PPL1-α3 negatively regulates forgotten one-trial conditioning memory retrieval. The current study demonstrated that KCαß, PPL1-α3, and MBON-α3 collaboratively regulate the formation of forgotten one-cycle aversive conditioning memory formation and retrieval.


Assuntos
Drosophila , Memória , Animais , Memória/fisiologia , Aprendizagem/fisiologia , Condicionamento Psicológico/fisiologia , Rememoração Mental/fisiologia
3.
Eur Respir J ; 59(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34385272

RESUMO

BACKGROUND: Inhibition of the epithelial sodium channel (ENaC) in cystic fibrosis (CF) airways provides a mutation-agnostic approach that could improve mucociliary clearance in all CF patients. BI 1265162 is an ENaC inhibitor with demonstrated pre-clinical efficacy and safety already demonstrated in humans. OBJECTIVE: We present results from BALANCE-CFTM 1, a phase II, placebo-controlled, randomised, double-blind study of four dose levels of BI 1265162 versus placebo for 4 weeks on top of standard of care in adults and adolescents with CF. RESULTS: Initially, 28 randomised subjects (BI 1265162 200 µg twice daily n=14, placebo twice daily n=14) were assessed at an interim futility analysis. Compared with placebo, numerical changes of -0.8% (95% CI -6.6 to 4.9%) in percentage predicted forced expiratory volume in 1s (ppFEV1) and +2.1 units (95% CI -2.4 to 6.5 units) in lung clearance index (LCI) were observed in the active group, meeting a pre-defined stopping rule; accordingly, the study was terminated. Recruitment had continued during the interim analysis and pending results; 24 patients were added across three dose levels and placebo. The final results including these patients (+1.5% ppFEV1, 200 µg twice-daily dose versus placebo) were not supportive of relevant clinical effect. Furthermore, LCI change was not supportive, although interpretation was limited due to insufficient traces meeting quality criteria. A 9.4-point improvement in the Cystic Fibrosis Questionnaire - Revised Respiratory Domain was observed in the 200 µg twice daily dose group versus placebo. BI 1265162 up to 200 µg twice daily was safe and well-tolerated. Pharmacokinetics were similar to those in healthy volunteers. CONCLUSION: BI 1265162 was safe, but did not demonstrate a potential for clinical benefit. Development has been terminated.


Assuntos
Fibrose Cística , Adolescente , Adulto , Fibrose Cística/tratamento farmacológico , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Método Duplo-Cego , Volume Expiratório Forçado , Humanos , Depuração Mucociliar , Testes de Função Respiratória/métodos
4.
Inorg Chem ; 60(23): 18270-18282, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34767721

RESUMO

A novel family of inorganic-organic-hybrid SeFe3(CO)9-dipyridyl two- and one-dimensional Cu polymers was synthesized via the three-component liquid-assisted grinding (LAG) of [Cu(MeCN)4]+, inorganic cluster [SeFe3(CO)9]2- (1), and rigid conjugated dipyridyls 4,4'-dipyridyl (dpy) and 1,2-bis(4-pyridyl)ethylene (bpee) or flexible conjugation-interrupted dipyridyls 1,2-bis(4-pyridyl)ethane (bpea) and 1,3-bis(4-pyridyl)propane (bpp). They included a cluster-linked 2D polymer, [(µ4-Se)Fe3(CO)9Cu2(MeCN)(dpy)1.5]n (1-dpy-2D), a cluster-pendant 1D chain, [(µ3-Se)Fe3(CO)9Cu2(dpy)3]n (1-dpy-1D), cluster-blocked 1D polymers, [(µ3-Se)Fe3(CO)9Cu2(L)]n (1-L-1D, L = bpee, bpea), and a cluster-linked 2D polymer, [(µ4-Se)Fe3(CO)9Cu2(bpp)2]n (1-bpp-2D). The reversible dimensionality transformations of these three types of polymers accompanied by the change in coordination modes of 1 were achieved by the LAG addition of 1/[Cu(MeCN)4]+ or dipyridyl ligands. These polymers were found to possess tunable low-energy gaps (1.49-1.72 eV) that increased in the order regarding their structural features: cluster-linked 1-dpy-2D and 1-bpp-2D, cluster-blocked 1-bpea-1D and 1-bpee-1D, and cluster-pendant 1-dpy-1D and [(µ3-Se)Fe3(CO)9Cu2(L)2.5]n (L = bpee, 1-bpee-2D; bpea, 1-bpea-2D), indicative of the importance of the participation of cluster 1. The measured electrical conductivities of 1-bpp-2D, 1-bpea-1D, and 1-dpy-1D were 3.13 × 10-7, 2.92 × 10-7, and 2.30 × 10-7 S·cm-1, respectively, which were parallel for the trend in their energy gaps, revealing semiconducting behaviors, supported by XPS, XANES, and DFT calculations. The surprising semiconductivity of the conjugation-interrupted bpp-linked 1-bpp-2D was mainly ascribed to electron transport via C-H···O(carbonyl) hydrogen bonds and aromatic C-H···π contacts within its closely packed 2D layers. Water-/light-stable polymers 1-bpp-2D, 1-bpea-2D, and 1-dpy-1D were also demonstrated to exhibit excellent pseudo-first-order photodegradation toward nitroaromatics and organic dyes, where cluster-linked polymer 1-bpp-2D performed the best, as predicted by its structural features and narrow energy gap.

5.
JTO Clin Res Rep ; 2(9): 100206, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34590052

RESUMO

INTRODUCTION: Insulin-like growth factor signaling has been implicated in acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) in NSCLC. This phase 1 trial (NCT02191891) investigated the combination of xentuzumab (an insulin-like growth factor-ligand neutralizing monoclonal antibody) and afatinib (an EGFR TKI) in patients with previously treated EGFR mutation-positive NSCLC. METHODS: The trial comprised dose escalation (part A) and expansion (part B). Patients had advanced or metastatic NSCLC that had progressed on EGFR TKI monotherapy or platinum-based chemotherapy (nonadenocarcinoma only, part A) or irreversible EGFR TKI monotherapy (part B). Absence of EGFR T790M mutation was required in part B. Part A used a 3 + 3 design, with a starting dose of xentuzumab 1000 mg/wk (intravenous) and afatinib 30 mg/d (oral). Primary endpoints were the maximum tolerated dose of the combination (part A) and objective response (part B). RESULTS: A total of 16 patients each were treated in parts A and B. Maximum tolerated dose was xentuzumab 1000 mg/wk plus afatinib 40 mg/d. No patients in part B had an objective response, but 10 had stable disease (median [range] duration of disease control: 2.3 [0.8-10.9] mo). The most common drug-related adverse events were diarrhea (75 %), paronychia (69 %), and rash (69 %) in part A and diarrhea (31 %), rash (19 %), paronychia (19 %), and fatigue (19 %) in part B. CONCLUSIONS: There were no new safety issues; xentuzumab and afatinib could be safely coadministered. Nevertheless, the combination revealed only modest activity in patients with EGFR mutation-positive, T790M-negative NSCLC after progression on afatinib.

6.
ERJ Open Res ; 6(4)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33313307

RESUMO

Inhibition of the epithelial sodium channel (ENaC) represents an important, mutation-agnostic therapeutic approach to restore airway surface liquid in patients with cystic fibrosis (CF). A phase II trial of the ENaC inhibitor BI 1265162, inhaled via the Respimat® Soft Mist™ inhaler, in patients aged ≥12 years with CF is being conducted to assess the efficacy and safety of BI 1265162, on top of standard CF treatment (www.clinicaltrials.gov identifier NCT04059094). BALANCE-CF™ 1 is a multinational, randomised, double-blind, placebo-controlled, parallel-group, dose-ranging trial consisting of 2 weeks' screening, 4 weeks' randomised treatment and 1 week follow-up. 98 patients, including ≥21 adolescents, will be randomised. First, 28 patients will be allocated to the highest dose of BI 1265162 (200 µg twice daily) or placebo in a 1:1 ratio. The remaining 70 patients will be allocated to one of five treatment arms (200 µg, 100 µg, 50 µg, 20 µg or placebo twice daily), with a final distribution ratio of 2:1:1:1:2. Recruitment and randomisation will begin with adult patients. An independent data monitoring committee will review safety data to advise on inclusion of adolescents and study continuation. A futility analysis will be conducted after 28 patients to prevent exposure of further patients in case of insufficient evidence of clinical efficacy. The design ensures that potential for effect is assessed ahead of wider enrolment, allowing investigation of a dose-response effect with minimal patient numbers. The results will increase understanding of efficacy, safety and optimal dosing of the inhaled ENaC inhibitor BI 1265162 in adults and adolescents with CF.

7.
J Phys Chem B ; 109(27): 13056-9, 2005 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-16852622

RESUMO

In this letter, we report a one-step templating synthetic strategy to prepare aligned TiO2 nanotube and nanowire arrays on Si substrate from a solution at ambient temperature. The deposition of TiO2 and the selective-etching of the ZnO template proceeded at the same time through the careful control of process parameters. The different thickness of TiO2 sheaths, leading to the formation of nanotubes or nanorods, can be precisely controlled by the deposition time. The idea of selective etching and deposition is applicable to other oxide materials, and such a facile method is expected to find widespread applications.

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