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Negative-pressure pulmonary edema (NPPE) arises from excessive inspiratory effort due to upper airway obstruction, often associated with postoperative laryngospasm and upper airway infections like epiglottitis. We present a case of NPPE during bronchoscopy. A 45-year-old female patient, who was undergoing bronchoscopy for interstitial pneumonia evaluation, was examined using a tracheal tube with a 7.5 mm internal diameter and a bronchoscope with a 5.9 mm external diameter. The patient's respiratory condition gradually worsened after intubation. We continued with the examination, supplying approximately 5 L/min of oxygen through the intubation tube. We performed an alveolar lavage, and the recovered fluid gradually turned pale and bloody. After the examination, the patient continued to expectorate pink and frothy sputum and prolonged respiratory failure. Chest radiography revealed new extensive bilateral infiltrates. We ruled out cardiogenic causes through clinical examination, electrocardiogram (ECG), and transthoracic echocardiography. As a result, we suspected that temporary upper airway obstruction during bronchoscopy led to NPPE. Applying continuous positive airway pressure (CPAP) quickly improved the pulmonary edema. The risk of NPPE during bronchoscopy needs to be acknowledged, especially when using larger bronchoscopes and smaller tracheal tubes.
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OBJECTIVES: To investigate the effectiveness of BMAX, a deep learning-based computer-aided detection system for detecting fibrosing interstitial lung disease (ILD) on chest radiographs among non-expert and expert physicians in the real-world clinical setting. DESIGN: Retrospective, observational study. SETTING: This study used chest radiograph images consecutively taken in three medical facilities with various degrees of referral. Three expert ILD physicians interpreted each image and determined whether it was a fibrosing ILD-suspected image (fibrosing ILD positive) or not (fibrosing ILD negative). Interpreters, including non-experts and experts, classified each of 120 images extracted from the pooled data for the reading test into positive or negative for fibrosing ILD without and with the assistance of BMAX. PARTICIPANTS: Chest radiographs of patients aged 20 years or older with two or more visits that were taken during consecutive periods were accumulated. 1251 chest radiograph images were collected, from which 120 images (24 positive and 96 negative images) were randomly extracted for the reading test. The interpreters for the reading test were 20 non-expert physicians and 5 expert physicians (3 pulmonologists and 2 radiologists). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the comparison of area under the receiver-operating characteristic curve (ROC-AUC) for identifying fibrosing ILD-positive images by non-experts without versus with BMAX. The secondary outcome was the comparison of sensitivity, specificity and accuracy by non-experts and experts without versus with BMAX. RESULTS: The mean ROC-AUC of non-expert interpreters was 0.795 (95% CI; 0.765 to 0.825) without BMAX and 0.825 (95% CI; 0.799 to 0.850) with BMAX (p=0.005). After using BMAX, sensitivity was improved from 0.744 (95% CI; 0.697 to 0.791) to 0.802 (95% CI; 0.754 to 0.850) among non-experts (p=0.003), but not among experts (p=0.285). Specificity and accuracy were not changed after using BMAX among either non-expert or expert interpreters. CONCLUSION: BMAX was useful for detecting fibrosing ILD-suspected chest radiographs for non-expert physicians. TRIAL REGISTRATION NUMBER: jRCT1032220090.
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Aprendizaje Profundo , Enfermedades Pulmonares Intersticiales , Humanos , Estudios Retrospectivos , Técnicos Medios en Salud , ComputadoresAsunto(s)
Compuestos de Anilina , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Glomerulonefritis , Ácidos Nipecóticos , Proteinosis Alveolar Pulmonar , Humanos , Rituximab/uso terapéutico , Anticuerpos Anticitoplasma de Neutrófilos , Glomerulonefritis/tratamiento farmacológicoRESUMEN
The relationships between T follicular helper (Tfh) cells and antigen-specific immunoglobulins (sIgs) in patients with allergic respiratory diseases who are receiving antigen immunotherapy (AIT) have not been fully clarified. Therefore, we started to perform house dust mite sublingual immunotherapy (HDM-SLIT) for 20 patients with atopic asthma comorbid with allergic rhinitis (AA+AR) who were already receiving ordinary treatments including inhaled corticosteroid (ICS). We examined percentages of circulating T follicular helper (cTfh) and regulatory (cTfr) cells and percentages of circulating regulatory T (cTreg) and B (cBreg) cells by FACS and we examined levels of Der-p/f sIgs by ELISA. Based on the symptom score (asthma control questionnaire: ACQ) and medication score ((global initiative for asthma: GINA) treatment step score) in patients with AA, the patients were divided into responders and non-responders. The percentage of cTfh2 cells significantly decreased and the percentage of cTfh1 cells significantly increased within the first year. Der-p/f sIgEs decreased after a transient elevation at 3 months in both groups. Notably, the percentage of cTfh2 cells and the ratio of cTfh2/cBreg cells and Der-p/f sIgEs greatly decreased in responders from 6 months to 12 months. The percentages of cTfr and cTreg cells showed significant negative correlations with the percentage of cTfh2 cells. The percentage of IL-4+ cTfh cells were significantly decreased and the percentage of IFN-γ+ cTfh cells were increased before treatment to 24 months in 6 patients examined (4 responders and 2 non-responders). We performed multi plelogistic regression analysis based on these results, the ratios of cTfh2/cTfr cells and cTfh2/cBreg cells at the start of therapy were statistically effective biomarkers for predicting the response to HDM-SLIT in patients with AA+AR.
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Asma , Linfocitos B Reguladores , Trastornos Respiratorios , Inmunoterapia Sublingual , Animales , Humanos , Pyroglyphidae , Dermatophagoides pteronyssinus , Linfocitos T Reguladores , Biomarcadores , Células T Auxiliares FolicularesRESUMEN
BACKGROUND: Alectinib, crizotinib, and ceritinib, are anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs) that exhibit high protein binding, and their metabolism is associated with the cytochrome P450 (CYP) isoenzymes 2C9 or 3A4. The plasma protein binding rate of warfarin, which is used to prevent and treat venous thromboembolism, is also high. Warfarin is a racemate of S-warfarin and R-warfarin, which are metabolized by CYP2C9 and CYP3A4, respectively. Reports on the drug interactions between each of the above-mentioned ALK-TKIs and warfarin with concurrent use of bucolome are currently lacking. CASE PRESENTATION: We report a case of a patient receiving warfarin and bucolome, whose international normalized ratio (INR) increased after sequential treatment with alectinib, crizotinib, and ceritinib. The patient was a 61-year-old man with a history of aortic valve regurgitation, who was receiving warfarin treatment following aortic valve replacement. Bucolome, which can enhance the effect of warfarin, was also used simultaneously. The patient was diagnosed with primary lung adenocarcinoma, and ALK rearrangement was detected during second-line chemotherapy. After progression of the disease with chemotherapy, sequential treatment with alectinib, crizotinib, and ceritinib was initiated. Pretreatment INR values were in the therapeutic range (target INR of 2-3) but increased to supratherapeutic levels each time after initiation of alectinib, crizotinib, or ceritinib treatment. Adjustment of warfarin dose or discontinuation of bucolome were necessary to maintain the therapeutic INR range. There were no serious bleeding events or substantial changes in dietary intake. Displacement of plasma protein binding or competitive inhibition of metabolism by alectinib, crizotinib, and ceritinib could increase the plasma concentration of the unbound form of warfarin, resulting in high INR values. In addition, alectinib, crizotinib, and ceritinib might cause displacement of bucolome from plasma proteins, followed by displacement of warfarin or inhibition of warfarin metabolism caused by the unbound form of bucolome. CONCLUSIONS: Close monitoring of INR and adjustment of warfarin dosage are needed during treatment with alectinib, crizotinib, or ceritinib in patients who receive warfarin with concurrent use of bucolome.
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Immune checkpoint inhibitors (ICIs) for various types of malignancy, including non-small-cell lung cancer, have improved prognosis in some cases. Granuloma formation after ICI administration suggests a tumor antigen-specific cytotoxic T cell response with abundant interferon-gamma production, which can be used to estimate the curative effect of ICIs. In this report, we present a case with a resected lung lesion, clinically suspected to be lung cancer, that consisted of a granulomatous lesion. A tumor was also found in the duodenum that was presumed to be derived from the pulmonary pleomorphic carcinoma. Duodenal tumor cells highly expressed PD-L1, suggesting PD-1/PD-L1 axis-mediated immune escape. As expected, pembrolizumab induced a complete response for the duodenal lesion. Interestingly, in histopathological analysis, the duodenal lesion was also replaced by an epithelial granuloma and multinucleated giant cells. We conclude that autoimmunity regressed the untreated primary lung lesion spontaneously, while the metastatic duodenal lesion responded to PD-1 blockade. Tumor-associated epithelioid granulomas, even before ICI administration, may be an important pathological finding indicating an immune response with interferon-gamma production by cytotoxic T cells to the tumor.
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Carcinoma de Pulmón de Células no Pequeñas , Carcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Antígeno B7-H1/análisis , Receptor de Muerte Celular Programada 1 , Interferón gamma , Granuloma/etiología , Pulmón/patologíaRESUMEN
BACKGROUND: Antifibrotic therapies are available to treat chronic fibrosing interstitial lung diseases (CF-ILDs), including idiopathic pulmonary fibrosis. Early use of these treatments is recommended to slow deterioration of respiratory function and to prevent acute exacerbation. However, identifying patients in the early stages of CF-ILD using chest radiographs is challenging. In this study, we developed and tested a deep-learning algorithm to detect CF-ILD using chest radiograph images. METHOD: From the image archive of Sapporo Medical University Hospital, 653 chest radiographs from 263 patients with CF-ILDs and 506 from 506 patients without CF-ILD were identified; 921 were used for deep learning and 238 were used for algorithm testing. The algorithm was designed to output a numerical score ranging from 0 to 1, representing the probability of CF-ILD. Using the testing dataset, the algorithm's capability to identify CF-ILD was compared with that of doctors. A second dataset, in which CF-ILD was confirmed using computed tomography images, was used to further evaluate the algorithm's performance. RESULTS: The area under the receiver operating characteristic curve, which indicates the algorithm's detection capability, was 0.979. Using a score cut-off of 0.267, the sensitivity and specificity of detection were 0.896 and 1.000, respectively. These data showed that the algorithm's performance was noninferior to that of doctors, including pulmonologists and radiologists; performance was verified using the second dataset. CONCLUSIONS: We developed a deep-learning algorithm to detect CF-ILDs using chest radiograph images. The algorithm's detection capability was noninferior to that of doctors.
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Aprendizaje Profundo , Fibrosis Pulmonar Idiopática , Enfermedades Pulmonares Intersticiales , Humanos , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Fibrosis , Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Algoritmos , Estudios RetrospectivosRESUMEN
Pulmonary pleomorphic carcinoma is rare among lung tumors. Pulmonary pleomorphic carcinoma is resistant to chemotherapy. However, treatment with taxane anticancer agents and immune checkpoint inhibitors has been reported to be effective. When using immune checkpoint inhibitors, pseudoprogression and true progression are difficult to distinguish, and immune-related adverse events (irAEs) are common. We herein report a patient with simultaneous pseudoprogression and irAEs after combined therapy with cytotoxic agents and an immune checkpoint inhibitor for pulmonary pleomorphic carcinoma. Immune checkpoint inhibitors are effective against pulmonary pleomorphic carcinoma, but patients should be monitored for pseudoprogression and irAEs.
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Antineoplásicos , Carcinoma , Neoplasias Pulmonares , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Citotoxinas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/efectos adversosRESUMEN
During mitosis, spatiotemporal regulation of phosphorylation at the kinetochore is essential for accurate chromosome alignment and proper chromosome segregation. Aurora B kinase phosphorylates kinetochore substrates to correct improper kinetochore-microtubule (KT-MT) attachments, whereas tension across the centromeres inactivates Aurora B kinase, and PP2A phosphatase dephosphorylates the kinetochore proteins to stabilize the attachments. However, the molecular entity of the tension sensing mechanism remains elusive. In a previous report, we showed that centromeric SET/TAF1 on Sgo2 up-regulates Aurora B kinase activity via PP2A inhibition in prometaphase. Here we show that Aurora B and Bub1 at the centromere/kinetochore regulate both kinase activities one another in an inter-kinetochore distance-dependent manner, indicating a positive feedback loop. We further show that the centromeric pool of SET on Sgo2 depends on Bub1 kinase activity, and the centromeric localization of SET decreases in a distance-dependent manner, thereby inactivating Aurora B in metaphase. Consistently, ectopic targeting of SET to the kinetochores during metaphase hyperactivates Aurora B via PP2A inhibition, and thereby rescues the feedback loop. Thus, we propose that SET, Aurora B and Bub1 form a distance-dependent positive feedback loop, which spatiotemporally may act as a tension sensor at centromeres.
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Aurora Quinasa B/metabolismo , Centrómero/metabolismo , Proteínas de Unión al ADN/metabolismo , Retroalimentación Fisiológica , Histona Acetiltransferasas/metabolismo , Chaperonas de Histonas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/metabolismo , Fenómenos Biomecánicos , Activación Enzimática , Células HeLa , HumanosRESUMEN
BACKGROUND: CXCR5+ T follicular helper (TFH) cells primarily promote B cells to produce an antigen-specific antibody through germinal centers (GCs). TFH cells exist in circulation, and circulating(c) TFH2 cells, a subset of cTFH cells, are able to help naïve B cells produce IgE in healthy individuals. Conversely, IL-10-producing regulatory B (Breg) cells inhibit an accelerated immune response. METHODS: We investigated the roles of cTFH cells and cBreg cells based on a TH2 response in patients with atopic asthma (AA). Thirty-two patients with AA and 35 healthy volunteers (HV) were enrolled. We examined cTFH cells including their subsets, their expression of ICOS and PD-1, and cBreg cells by flow cytometry and their associations with clinical biomarkers. Plasma levels of CXCL13, which is a counterpart of CXCR5, were also measured using ELISA. RESULTS: In patients with AA, cTFH2 cells were increased and cTFH1 cells were decreased compared with those in HV. The expression levels of ICOS on cTFH and their subset cells were elevated and Breg cells were greatly decreased. The plasma levels of CXCL13 in patients with AA were significantly elevated and correlated well with the cTFH2/cBreg ratio. These cells were examined in 10 patients AA before and after inhaled corticosteroid (ICS) treatment. Interestingly, the percentages and numbers of TFH2 and ICOS+ cTFH cells declined after ICS treatment together with improvements in symptoms and clinical biomarkers. CONCLUSIONS: The percentages and numbers of cTFH2 and ICOS+ cTFH cells might be useful as biomarkers of TH2 typed airway inflammation in patients with AA.
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Corticoesteroides/uso terapéutico , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Asma/inmunología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Administración por Inhalación , Adulto , Asma/sangre , Linfocitos B Reguladores/efectos de los fármacos , Linfocitos B Reguladores/inmunología , Quimiocina CXCL13/sangre , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T Colaboradores-Inductores/inmunología , Células Th2/efectos de los fármacos , Células Th2/inmunologíaRESUMEN
BACKGROUND: T follicular helper (Tfh) cells have been identified as a new category of helper T cells, which express CXCR5 on their surface and induce the production of antigen-specific antibodies. Many investigations have found morbid proliferation and/or activation of Tfh cells in systemic autoimmune and allergic diseases. It is also known that Tfh cells are regulated by regulatory B (Breg) cells in the deteriorating such diseases. Recently, CXCL13, a ligand of CXCR5, has been reported to increase in the peripheral blood and lungs of patients with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the involvement of Tfh cells and Breg cells in IPF. METHODS: Peripheral blood samples were obtained from 18 patients with IPF. We isolated heparinized peripheral blood mononuclear cells and investigated the proportions of Breg cells, Tfh cells, PD-1+ICOS+ Tfh cells (activated form of Tfh cells), and the Tfh-cell subsets by flow cytometry. These cell profiles were compared with those of 21 healthy controls. Furthermore, we investigated the correlations between profiles of lymphocytes and lung physiology. RESULTS: The median proportions of Tfh cells per total CD4+ T cells and of PD-1+ICOS+ proportion of Tfh cells per total Tfh cells was significantly more in the IPF patients (20.4 and 5.2%, respectively) compared with healthy controls (15.4 and 2.1%, respectively; p = 0.042 and p = 0.004, respectively). The proportion of Tfh2 cells per total Tfh cells was significantly higher and the proportion of Tfh17 was smaller in the IPF patients than healthy controls. The percentage of Breg cells to total B cells was significantly decreased in the IPF patients (median, 8.5%) compared with that in the controls (median, 19.7%; p < 0.001). The proportion of Breg cells was positively correlated with the annual relative change in diffusing capacity of the lungs for carbon monoxide in the IPF patients (r = 0.583, p = 0.018). CONCLUSION: Proliferation and activation of Tfh cells and a decrease in Breg cells were observed in the peripheral blood of patients with IPF. The profile of the Tfh-cell subset also changed. Specific humoral immunity aberration would likely underlie complicated pathophysiology of IPF.
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Autoinmunidad , Linfocitos B Reguladores/inmunología , Proliferación Celular , Fibrosis Pulmonar Idiopática/inmunología , Inmunidad Humoral , Activación de Linfocitos , Linfocitos T Colaboradores-Inductores/inmunología , Anciano , Anciano de 80 o más Años , Linfocitos B Reguladores/metabolismo , Biomarcadores/sangre , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Femenino , Humanos , Fibrosis Pulmonar Idiopática/sangre , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/fisiopatología , Proteína Coestimuladora de Linfocitos T Inducibles/sangre , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Fenotipo , Receptor de Muerte Celular Programada 1/sangre , Capacidad de Difusión Pulmonar , Receptores CXCR5/sangre , Linfocitos T Colaboradores-Inductores/metabolismoRESUMEN
The accurate regulation of phosphorylation at the kinetochore is essential for establishing chromosome bi-orientation. Phosphorylation of kinetochore proteins by the Aurora B kinase destabilizes improper kinetochore-microtubule attachments, whereas the phosphatase PP2A has a counteracting role. Imbalanced phosphoregulation leads to error-prone chromosome segregation and aneuploidy, a hallmark of cancer cells. However, little is known about the molecular events that control the balance of phosphorylation at the kinetochore. Here, we show that localization of SET/TAF1, an oncogene product, to centromeres maintains Aurora B kinase activity by inhibiting PP2A, thereby correcting erroneous kinetochore-microtubule attachment. SET localizes at the inner centromere by interacting directly with shugoshin 2, with SET levels declining at increased distances between kinetochore pairs, leading to establishment of chromosome bi-orientation. Moreover, SET overexpression induces chromosomal instability by disrupting kinetochore-microtubule attachment. Thus, our findings reveal the novel role of SET in fine-tuning the phosphorylation level at the kinetochore by balancing the activities of Aurora B and PP2A.
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Aurora Quinasa B/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centrómero/metabolismo , Proteínas de Unión al ADN/metabolismo , Histona Acetiltransferasas/metabolismo , Chaperonas de Histonas/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/metabolismo , Células Cultivadas , Células HEK293 , Células HeLa , HumanosRESUMEN
OBJECTIVE: Rapid on-site cytological evaluation (ROSE) in bronchoscopy is a useful ancillary technique. ROSE is usually performed by a cytopathologist or cytotechnologist. However, because of staff shortages and reduced availability, ROSE cannot be performed in every hospital. We aimed to evaluate the accuracy of ROSE when performed by a trained pulmonologist, comparing the diagnosis results with the final diagnosis of cytopathologists. METHODS: We performed a retrospective cohort study on 125 patients who underwent bronchoscopy with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endobronchial ultrasonography with a guide sheath (EBUS-GS) for peripheral pulmonary lesions by conventional bronchoscopy at Sapporo Medical University Hospital between March 2012 and September 2018. ROSE was performed by a pulmonologist who was trained by a cytotechnologist for a total of 1 month. DiffQuik® staining for ROSE was used to prepare cytology slides. The results of ROSE were compared with the final diagnosis obtained using Papanicolaou staining by cytopathologists. RESULTS: In all procedures, the sensitivity, specificity and diagnostic accuracy of ROSE were 88.5%, 83.0% and 86.4%, respectively. There was no significant difference in the sensitivity, specificity, positive predictive value, negative predictive value or accuracy between EBUS-TBNA and EBUS-GS. CONCLUSIONS: ROSE of lung cancer by a trained pulmonologist can be highly accurate and deemed as feasible and useful for not only EBUS-TBNA but also EBUS-GS.
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Citodiagnóstico , Neoplasias Pulmonares/diagnóstico , Pulmón/patología , Adulto , Anciano , Anciano de 80 o más Años , Broncoscopía/métodos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Femenino , Humanos , Biopsia Guiada por Imagen/métodos , Pulmón/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neumólogos , Estudios RetrospectivosRESUMEN
We present a case of ovarian clear-cell carcinoma that was initially diagnosed as adenocarcinoma of lung origin. This is an instructive diagnostic pitfall for clinicians and pathologists because of the unusual clinical course, small biopsy material, and noteworthy immunophenotype of the carcinoma. Imaging analysis identified only lung and liver lesions. In addition, the biopsy specimen from the lung was TTF-1 negative and napsin A positive, which is still possible for cancer of lung origin. Postmortem examination found that the cancer should be classified as ovarian clear-cell carcinoma distinguished by positive staining for napsin A and paired-box gene 8 (PAX8). Although PAX8 may not be usually investigated when tumoral lesions are identified in only the lung and liver, it is important to keep the necessity of PAX8 in mind to excluding carcinoma of Müllerian, renal, or thyroid origin.
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A series of paddlewheel diruthenium(ii, ii) complexes with various fluorine-substituted benzoate ligands were isolated as THF adducts and structurally characterized: [Ru(2)(F(x)PhCO(2))(4)(THF)(2)] (F(x)PhCO(2)(-) = o-fluorobenzoate, o-F; m-fluorobenzoate, m-F; p-fluorobenzoate, p-F; 2,6-difluorobenzoate, 2,6-F(2); 3,4-difluorobenzoate, 3,4-F(2); 3,5-difluorobenzoate, 3,5-F(2); 2,3,4-trifluorobenzoate, 2,3,4-F(3); 2,3,6-trifluorobenzoate, 2,3,6-F(3); 2,4,5-trifluorobenzoate, 2,4,5-F(3); 2,4,6-trifluorobenzoate, 2,4,6-F(3); 3,4,5-trifluorobenzoate, 3,4,5-F(3); 2,3,4,5-tetrafluorobenzoate, 2,3,4,5-F(4); 2,3,5,6-tetrafluorobenzoate, 2,3,5,6-F(4); pentafluorobenzoate, F(5)). By adding fluorine atoms on the benzoate ligands, it was possible to tune the redox potential (E(1/2)) for [Ru(2)(II,II)]/[Ru(2)(II,III)](+) over a wide range of potentials from -40 mV to 350 mV (vs. Ag/Ag(+) in THF). 2,3,6-F(3), 2,3,4,5-F(4), 2,3,5,6-F(4) and F(5) were relatively air-stable compounds even though they are [Ru(2)(II,II)] species. The redox potential in THF was dependent on an electronic effect rather than on a structural (steric) effect of the o-F atoms, although more than one substituent in the m- and p-positions shifted E(1/2) to higher potentials in relation to the general Hammett equation. A quasi-Hammett parameter for an o-F atom (σ(o)) was estimated to be â¼0.2, and a plot of E(1/2)vs. a sum of Hammett parameters including σ(o) was linear. In addition, the HOMO energy levels, which was calculated based on atomic coordinates of solid-state structures, as well as the redox potential were affected by adding F atoms. Nevertheless, a steric contribution stabilizing their static structures in the solid state was present in addition to the electronic effect. On the basis of the electronic effect, the redox potential of these complexes is correlated to the HOMO energy level, and the electronic effect of F atoms is the main factor controlling the ionization potential of the complexes with ligands free from the rotational constraint, i.e. complexes in solution.
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An alternating chain of a paddlewheel [Ru(2)(II,III)(O(2)CEt)(4)](+) (EtCO(2)(-) = propionate) complex and [Pt(mnt)(2)](-) (mnt(2-) = maleonitriledithiolate) has a ferrimagnetic spin arrangement of S = 3/2 and 1/2 local spins, respectively, as well as three-dimensional antiferromagnetic ordering with a canting mode at 8.6 K. This chain is stacked at the [Pt(mnt)(2)](-) units to form a slipped column in the vertical direction against the chain, which acts as a pathway for electrical conduction.