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1.
J Chem Phys ; 161(3)2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39017426

RESUMEN

Stepwise two-photon absorption processes have received considerable attention, especially in photocatalysis, due to their relatively lower power threshold, characteristic spatial selectivity, amplification of chemical reactions, and so on. Meanwhile, studies on the relaxation dynamics of higher excited states in condensed systems have been limited for several molecular systems due to the short-lived nature of these states. In this study, we synthesized perylene-substituted perylene bisimide (PBI) and its derivate as model compounds and investigated their excited-state dynamics, including higher excited states, using pump-repump-probe spectroscopy. We revealed that these molecules form charge-transfer (CT) states instantaneously after the excitation, regardless of whether it is the perylene moiety or the PBI moiety that is excited. The lifetime of the CT state was shorter when the distance between the donor (perylene) and the acceptor (PBI) was shorter. Moreover, we also revealed that a higher-lying CT state generated by the stepwise excitation of the CT state using a 740-nm pulse induced Stark effect to the neighboring perylene moiety. The Stark effect not only gives more detailed information about the CT state, but also presents the possibility of new photofunctions, such as instantaneous modulation of the electronic state to achieve optimal electronic properties. These insights contribute to understanding advanced photochemical reactions and would be important for exploring photocatalytic reactions involving higher excited states.

2.
Angew Chem Int Ed Engl ; : e202410115, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38894673

RESUMEN

A synergetic interaction between two or more photochromic chromophores has a potential to achieve advanced photochemical properties beyond conventional photochromic molecules and to realize photochemical control of complex systems using only a single molecule. Herein, we report a hybrid photochromic molecule consisting of hexaarylbiimidazole (HABI) and terarylene that exhibits multi-state photochromism. The biphotochrome hybrid shows four-state photochromic reaction involving sequentially proceeding photoreactions. The UV or visible light irradiation to the biphotochrome leads to the C-N bond breaking reaction of the HABI in preference to the ring-closing reaction of the 6π-electron system in the terarylene unit, leading two terarylene radical molecules. The photogenerated terarylene radical further exhibits the 6π-electrocyclization reaction by UV irradiation. The delocalized π-radical on the closed-ring form of the terarylene is efficient to enhance the photosensitivity to the NIR-I and -II region. Furthermore, a recombination reaction of radicals between the open- and closed-ring isomers of terarylene affords an unprecedented photochromic dimer as a structural isomer of the initial molecule. This is a consequence of the sequential hybrid photochromic system involving the HABI and terarylene units.

3.
Angew Chem Int Ed Engl ; : e202408687, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896058

RESUMEN

Perfluoroalkyl substances (PFASs) and fluorinated polymers (FPs) have been extensively utilized in various industries, whereas their extremely high stability poses environmental persistence and waste treatment. Current decomposition approaches of PFASs and FPs typically require harsh conditions such as heating over 400°C. Thus, there is a pressing need to develop a new technique capable of decomposing them under mild conditions. Here, we demonstrated that perfluorooctanesulfonate (PFOS), known as a "persistent chemical," and Nafion, a widely utilized sulfonated FP for ion-exchange membranes, can be efficiently decomposed into fluorine ions under ambient conditions via the irradiation of visible LED light onto semiconductor nanocrystals (NCs). PFOS was completely defluorinated within 8-h irradiation of 405-nm LED light, and the turnover number of the C-F bond dissociation per NC was 17200. Furthermore, 81% defluorination of Nafion was achieved for 24-h light irradiation, demonstrating the efficient photocatalytic properties under visible light. We revealed that this decomposition is driven by cooperative mechanisms involving light-induced ligand displacements and Auger-induced electron injections via hydrated electrons and higher excited states. This study not only demonstrates the feasibility of efficiently breaking down various PFASs and FPs under mild conditions but also paves the way for advancing toward a sustainable fluorine-recycling society.

4.
Chem Commun (Camb) ; 60(51): 6492-6495, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38807473

RESUMEN

We herein report photodoping and thereby photochromism of semiconductor nanocrystals under air in a temperature-responsive supramolecular gel and its back reactions induced by direct heating or near-infrared photothermal conversion. We also present their application to the spatiotemporal patterning of photoluminescence.

5.
J Obstet Gynaecol Res ; 50(7): 1182-1191, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38697202

RESUMEN

AIM: Quality of care is important to reduce disease progression, and improve both survival and quality of life. The Japan Society of Gynecologic Oncology has published treatment guidelines to promote standardized high-quality care for ovarian cancer in Japan. We developed quality indicators based on the guideline recommendations and used them on large datasets of health service use to examine the quality of ovarian cancer care. METHODS: A panel of experts developed the indicators using a modified Delphi method. Adherence to each indicator was evaluated using data from a hospital-based cancer registry of patients diagnosed in 2018. All patients receiving first-line treatment at participating facilities were included. The adherence rates were returned to participating hospitals, and reasons for nonadherence were collected. A total of 580 hospitals participated, and the study examined the care received by 6611 patients with ovarian cancer and 1879 with borderline tumors using 11 measurable quality indicators. RESULTS: The adherence rate ranged from 22.6% for "Estrogen replacement within 6 months of operation" to 93.5% for "Bleomycin, etoposide, and cisplatin for germ cell tumor more than Stage II." Of 580 hospitals, 184 submitted the reasons for nonadherence. CONCLUSIONS: The quality of ovarian cancer care should be continuously assessed to encourage the use of best practices. These indicators may be a useful tool for this purpose.


Asunto(s)
Neoplasias Ováricas , Indicadores de Calidad de la Atención de Salud , Calidad de la Atención de Salud , Humanos , Femenino , Neoplasias Ováricas/terapia , Japón , Calidad de la Atención de Salud/normas , Adhesión a Directriz/estadística & datos numéricos
6.
Angew Chem Int Ed Engl ; 63(24): e202404140, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38596881

RESUMEN

Nonlinear photochromic reactions that work with weak incoherent light are important for molecular operations with high spatial resolution and multiple photofunctions based on single molecules. However, nonlinear photochromic compounds generally require complex molecular design, restricting accessibility in various fields. Herein, we report nonlinear photochromic properties in a perylene-substituted rhodamine spirolactam derivative (Rh-Pe), which is synthesized from rhodamine B in facile procedures. Direct excitation of Rh-Pe produces the triplet excited state via the charge-transfer (CT) state. The triplet excited state causes triplet-triplet annihilation to bring the generation of the intensely colored ring-open form with nonlinear behavior. Furthermore, green- and red-light-induced photochromism was achieved in Rh-Pe using triplet sensitizers, although Rh-Pe can be directly excited only by ultraviolet and blue light. Our findings are expected to contribute to the development of photofunctional materials showing nonlinear behavior and low-energy light responsivity.

8.
RSC Adv ; 14(4): 2796-2803, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38234874

RESUMEN

Organic ligands on the surface of nanocrystals (NCs) are extremely important in influencing various physical properties, such as dispersibility, electrical properties, and optical properties. Recent studies have revealed that a slight difference in the molecular structure of aliphatic organic ligands significantly affects the dispersibility of the NCs. On the other hand, the effects of the difference in the molecular structure of ligands on the excited-state dynamics of NCs remain elusive. In this study, we synthesized a series of colloidal ZnO NCs capped with different alkyl phosphonic acids and investigated their photophysical properties using emission decay measurements and transient absorption spectroscopy. The spectral shape and lifetime of the emission originating from the surface oxygen defects of ZnO NCs are almost the same irrespective of the alkyl phosphonic ligands used, indicating that the electronic states of the surface oxygen defects are not affected by the bulkiness of the ligand. On the other hand, the emission quantum yield correlates with the rate of carrier trapping by oxygen defects, suggesting that the rate of carrier trapping reflects the number of oxygen defects. Revealing the detailed relationship between molecular structures of organic ligands and the optical properties of NCs is important for advanced photofunctional superstructures using semiconductor NCs.

9.
Jpn J Clin Oncol ; 54(2): 217-220, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-37823222

RESUMEN

In association with an update of the Japan Society of Gynecologic Oncology clinical practice guidelines for endometrial cancer in 2023, a systematic review was conducted about the therapeutic benefit of adjuvant therapy on patients with early-stage endometrial carcinoma, who presented positive peritoneal cytology (PPC) without the risk factors for recurrence. The systematic review only included two eligible retrospective studies. Both studies included patients with risk factors for recurrence. A nationwide study in the United States reported that adjuvant chemotherapy was associated with the reduced risk of death among patients with stages I-II endometrial cancer with PPC by multivariate, propensity score-adjusted analysis. Another single-center study in Japan reported no association between adjuvant chemotherapy and relapse-free survival among patients with stage IA endometrial cancer by univariate analysis. This systematic review identified that evidence was limited with conflicting results. Continuous evaluation is warranted to address this clinical question.


Asunto(s)
Citología , Neoplasias Endometriales , Humanos , Femenino , Pronóstico , Estudios Retrospectivos , Estadificación de Neoplasias , Japón , Recurrencia Local de Neoplasia/patología , Neoplasias Endometriales/patología , Quimioterapia Adyuvante
10.
J Gynecol Oncol ; 35(1): e15, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38037547

RESUMEN

The Japan Society of Gynecologic Oncology (JSGO) Guidelines 2022 for the Treatment of Uterine Cervical Cancer are revised from the 2017 guideline. This guideline aimed to provide standard care for cervical cancer, indicate appropriate current treatment methods for cervical cancer, minimize variances in treatment methods among institutions, improve disease prognosis and treatment safety, reduce the economic and psychosomatic burden of patients by promoting the performance of appropriate treatment, and enhance mutual understanding between patients and healthcare professionals. The guidelines were prepared through the consensus of the JSGO Guideline Committee, based on a careful review of evidence gathered through the literature searches and the medical health insurance system and actual clinical practice situations in Japan. The guidelines comprise seven chapters and 5 algorithms. The main features of the 2022 revision are as follows: 1) added discussed points at the final consensus meeting; 2) revised the treatment methods based on the International Federation of Gynecology and Obstetrics 2018 staging system; 3) examined minimally invasive surgery based on Laparoscopic Approach to Cervical Cancer trial; 4) added clinical question (CQ) for treatments of rare histological types, gastric type, and small-cell neuroendocrine carcinoma; 5) added CQ for intensity-modulated radiation therapy; 6) added CQ for cancer genomic profiling test; and 7) added CQ for cancer survivorship. Each recommendation is accompanied by a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSGO Guidelines 2022 for the Treatment of Uterine Cervical Cancer.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Embarazo , Japón , Estadificación de Neoplasias , Pronóstico , Sociedades Médicas , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/patología
11.
Respir Med ; 221: 107497, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38097142

RESUMEN

OBJECTIVE: To determine prognostic factors of virus-associated pneumonia other than coronavirus disease 2019. METHODS: We retrospectively studied patients suffering from virus-associated community-acquired pneumonia, and who were admitted to Saitama Cardiovascular and Respiratory Center from 2002 to 2020. Prognostic factors were analyzed by univariable and multivariable regression analysis of patient demographics, laboratory data, chest imaging, severity on admission, and initial treatment. PATIENTS: HIV-positive patients, those with non-resected lung cancer or receiving chemotherapy, and those with COVID-19 were excluded. Included were 363 patients diagnosed by nucleic acid amplification method, paired sera, and rapid diagnostic tests. RESULTS: A CURB-65 score of ≥3 was significant by univariable analysis for 60-day mortality but was nonsignificant by multivariable analysis. The poor prognostic factors that were significant by multivariable analysis (p < 0.05) included immunosuppressive state due to systemic corticosteroid or immunosuppressant administration, acute kidney injury on admission, and corticosteroid administration initiated within 5 days or 5 days to 2 weeks from onset. CONCLUSION: A CURB-65 score of ≥3, which is considered to indicate severe pneumonia, was of limited value for predicting mortality of virus-associated pneumonia. We showed patients' underlying diseases and complications to be independent factors of poor prognosis for 60-day mortality. Timing of the initiation of corticosteroid administration remains to be elucidated.


Asunto(s)
COVID-19 , Infecciones Comunitarias Adquiridas , Neoplasias Pulmonares , Neumonía , Adulto , Humanos , COVID-19/complicaciones , Pronóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Corticoesteroides/uso terapéutico
12.
J Phys Chem Lett ; 14(50): 11474-11479, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38085931

RESUMEN

Photochromic reactions of the phenoxyl-imidazolyl radical complex (PIC), which is one of the rate-tunable fast T-type photoswitches, dramatically change by the introduction of bulky substituents around the photochromic units. While these substituents are expected to affect the initial bond dissociation processes, they have not been elucidated yet. Here, we revealed the ultrafast bond dissociation processes of PIC derivatives with different bulky substituents by subpicosecond to nanosecond transient absorption spectroscopy. We revealed that the bulky substituents around the photochromic units decelerate the bond dissociation processes, whereas they largely accelerate the thermal back reactions of the photogenerated open-ring isomer. Moreover, we found clear correlations between the formation kinetics of the open-ring isomer and molecular structural changes. The initial bond-dissociation process dictates the products and the efficiency of photochromic reactions. Therefore, revealing these processes is important not only for fundamental photochemistry but also for optimizing photochromic properties for advanced functional materials.

13.
Respir Med Case Rep ; 46: 101940, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025251

RESUMEN

A 55-year-old man presented to our institution with abnormal chest X-ray shadows. Chest computed tomography (CT) showed left-sided interlobular septal thickening; thus, we suspected lymphangitis carcinomatosis and other disorders that show similar CT findings. Bronchoscopy and laboratory and imaging studies yielded no diagnostic findings. Pulmonary shadows during follow-up spontaneously improved then worsened. Thoracoscopic lung biopsy samples showed interstitial pneumonia and granulomas but the etiology of the pulmonary lesion could not be determined. At seven years after presentation, the patient's pulmonary shadows had gradually deteriorated, and he reported using topical minoxidil. His history of minoxidil use was linked to changes in the pulmonary shadows. The diagnostic delay was due to the patient's hesitancy to report drugs obtained online and the difficulty in obtaining such a history.

14.
J Obstet Gynaecol Res ; 49(12): 2883-2888, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37735981

RESUMEN

AIM: Ovarian cancer is a gynecological malignancy with a poor prognosis. For platinum-sensitive relapsed ovarian cancer, maintenance therapy with poly-ADP ribose polymerase (PARP) inhibitors after chemotherapy is considered; however, olaparib treatment does not always lead to sufficient progression-free survival (PFS). This study aimed to identify factors that predict the efficacy of maintenance therapy using olaparib in platinum-sensitive relapsed ovarian cancer. METHODS: Twenty-seven patients with platinum-sensitive relapsed ovarian cancer, who received initial treatment and showed complete or partial response to prior chemotherapy at our hospital, were included. The primary outcome was the time from the end of previous platinum-based chemotherapy to disease progression (PFS). The Kaplan-Meier method was used to generate time-to-event curves for PFS; multivariate analysis was performed using the Cox proportional hazards regression model. RESULTS: The median PFS was 12 months (95% confidence interval [CI]: 8.3-15.8). Before olaparib administration, the median PFS was 12 months in the <4.1 neutrophil-to-lymphocyte ratio group and 4 months in the ≥4.1 group, with PFS being significantly better in the <4.1 group (log-rank: p = 0.023). When comparing serum cancer antigen 125 (CA125) levels, the median PFS was 13 months in the <18 U/mL group and 6 months in the >18 U/mL group (log-rank: p = 0.022). Multivariate Cox regression analysis revealed that CA125 was the factor affecting PFS (hazard ratio: 4.85; 95% CI: 1.53-15.38). CONCLUSIONS: Serum CA125 levels at olaparib initiation in patients with platinum-sensitive relapsed ovarian cancer may predict PFS as an effect of maintenance therapy using olaparib to treat recurrent disease.


Asunto(s)
Neoplasias Ováricas , Ftalazinas , Piperazinas , Femenino , Humanos , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Ftalazinas/farmacología , Ftalazinas/uso terapéutico , Piperazinas/farmacología , Piperazinas/uso terapéutico
15.
Gynecol Oncol Rep ; 49: 101252, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37583589

RESUMEN

Several types of mucinous lesions of the fallopian tube have been reported, including metaplastic and neoplastic lesions, most of which exhibit gastric phenotypes. Here, we report a unique case of a mucinous tumor arising in the right fallopian tube of a 36-year-old female who presented with refractory abdominal pain for approximately one year. Abdominal CT and MRI found a cystic lesion leading to the diagnosis of hematosalpinx, thus right salpingo-oophorectomy and appendectomy were performed. Macroscopic findings included cystic dilatation of the distal portion of the right fallopian tube, filled with gelatinous mucin. Histologically, mucinous columnar cells proliferated in papillary configurations in the cystic region without invasion, resembling low-grade appendiceal mucinous neoplasms. Immunohistochemical analysis revealed that the neoplastic cells expressed CDX-2 and SATB2, but not WT-1, PAX8, ER, PgR, or claudin 18. Sanger sequencing of the mucinous lesion identified a KRAS exon 2 mutation (p.G12A), confirming similar pathologic and genetic characteristics to ovarian mucinous borderline tumors. This rare low grade intestinal-type mucinous tumor indicates the fallopian tube epithelium can give rise to tumors resembling low-grade appendiceal mucinous neoplasms and cause pseudomyxoma peritonei without appendiceal lesions.

17.
Chem Commun (Camb) ; 59(57): 8850-8853, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37368414

RESUMEN

We demonstrate that the phenoxyl-imidazolyl radical complex (PIC), which is a rate-tunable fast photoswitch, can be used as a ligand that directly coordinates with iridium (III) ions. The iridium complexes show the characteristic photochromic reactions originating from the PIC moiety, whereas the behaviour of transient species is substantially different from that of the PIC.

18.
J Am Chem Soc ; 145(20): 11236-11244, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37126432

RESUMEN

The optical property of an ionic metal nanocluster (NC) is affected by the ionic interaction with counter ions. Here, we report that the modification of trianionic [Ag29(BDT)12(TPP)4]3- NC (BDT: 1.3-benzenedithiol; TPP: triphenylphosphine) with silver(I) complexes led to the intense photoluminescence (PL) in the near-infrared (NIR) region. The binding of silver(I) complexes to the peripheral region of Ag29 NC is confirmed by the single-crystal X-ray diffraction (SCXRD) measurement, which is further supported by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy. The change of excited-state dynamics by the binding of silver(I) complexes is discussed based on the results of a transient absorption study as well as temperature-dependent PL spectra and PL lifetime measurements. The modification of Ag29 NCs with cationic silver(I) complexes is considered to give rise to a triplet excited state responsible for the intense NIR PL. These findings also afford important insights into the origin of the PL mechanism as well as the possible light-driven motion in Ag29-based NCs.

19.
Org Lett ; 25(20): 3676-3681, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37172277

RESUMEN

Dithienylnitrophenols were synthesized as precursors of π-electronic anions, which were stabilized by intramolecular chalcogen bonding, forming various ion pairs in combination with cations. The modes of solid-state charge-by-charge assemblies, along with solution-state stacking and photoinduced electron transfer behaviors, were modulated by the constituent ionic species.

20.
ACS Nano ; 17(12): 11309-11317, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37159862

RESUMEN

Organic-inorganic nanohybrids using semiconductor nanocrystals (NCs) coordinated with aromatic organic molecules have been widely studied in the fields of optoelectronic materials, such as solar cells, photocatalysis, and photon upconversion. In these materials, coordination bonds of ligand molecules are usually assumed to be stable during optical processes. However, this assumption is not always valid. In this study, we demonstrate that the coordination bonds between ligand molecules and NCs by carboxyl groups are displaced quasi-reversibly by light irradiation using zinc sulfide (ZnS) NCs coordinated with perylenebisimide (PBI) as a model system. Time-resolved spectroscopy over a wide range of time from tens-of femtosecond to second timescales and density functional theory calculations show that the photoinduced ligand displacement is driven by ultrafast hole transfer from PBI to ZnS NCs and that the dissociated radical anion of PBI survives over the second timescale. Photoinduced ligand displacements are important to be considered in various organic-inorganic nanohybrids and offer a possibility of NCs covered by nonphotoresponsive organic ligands for advanced photofunctional materials.

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