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1.
Article in English | MEDLINE | ID: mdl-38781486

ABSTRACT

BACKGROUND AND IMPORTANCE: A double-layer micromesh stent is designed for the treatment of carotid artery stenosis that has been reported to potentially provide a flow diversion effect. However, the actual flow diversion effect of stents remains unclear. Here, we present a case of a growing saphenous vein graft (SVG) aneurysm treated with the placement of the double-layer micromesh stent using its flow diversion effect. CLINICAL PRESENTATION: A 66-year-old woman, who underwent high-flow bypass using a SVG for a blister-like internal carotid artery aneurysm 13 years earlier at our institute, was referred to our hospital with a pulsatile cervical mass. Magnetic resonance angiography showed a 9-mm aneurysm on the left SVG, although the aneurysm was a small pouch 4 years earlier. Digital subtracted angiography demonstrated a 9.4 × 8.3-mm aneurysm from the SVG at the auricular level. Because the diameter of the graft was larger than that of the available flow diverter stents in Japan, we decided to place the double-layer micromesh stent (CASPER RX, 7 × 25 mm MicroVention) using its flow diversion effect. Computational fluid dynamics analysis before and after stent deployment showed a significant reduction in the average flow velocity and wall shear stress in the aneurysm, indicating actual flow diversion. An angiogram 2 months postoperatively showed complete obliteration of the aneurysm. CONCLUSION: Obliteration of the saphenous vein aneurysm was achieved because of the flow diversion effect of the double-layer micromesh stent. The stents might be a feasible alternative for treating cervical carotid aneurysms.

2.
Neurosurg Rev ; 47(1): 91, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38379090

ABSTRACT

Although cognitive decline after carotid endarterectomy (CEA) is mainly related to postoperative cerebral hyperperfusion, approximately 30% of patients with cognitive decline do not have postoperative cerebral hyperperfusion. In patients with acute ischemic events, the development of cognitive decline after such events is associated with the presence of chronic cerebral white matter hyperintensities (WMHs). The present prospective observational study aimed to determine whether preoperative WMHs and postoperative new ischemic lesions (PNILs) are associated with cognitive decline after CEA in patients without cerebral hyperperfusion after CEA. Brain magnetic resonance imaging (MRI) was performed preoperatively, and WMHs were graded according to the Fazekas scale in patients undergoing CEA for severe stenosis of the ipsilateral internal carotid. Diffusion-weighted MRI was performed before and after CEA to determine the development of PNILs. Neuropsychological testing was performed preoperatively and at 2 months postoperatively to determine the development of postoperative cognitive decline (PCD). In 142 patients without postoperative cerebral hyperperfusion, logistic regression analysis revealed that preoperative Fazekas scale of periventricular WMHs (PVWMHs) (95% confidence interval [CI]: 1.78-28.10; P = 0.0055) and PNILs in the eloquent areas (95% CI: 7.42-571.89; P = 0.0002) were significantly associated with PCD. The specificity and positive-predictive value for the prediction of PCD were significantly greater for the combination of preoperative Fazekas scale 2 or 3 of PVWMHs and PNILs in the eloquent areas than for each individually. Preoperative PVWMHs, PNILs in the eloquent areas, and the combination of both were associated with PCD in patients without cerebral hyperperfusion after CEA.


Subject(s)
Carotid Stenosis , Cognitive Dysfunction , Endarterectomy, Carotid , White Matter , Humans , Endarterectomy, Carotid/adverse effects , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/surgery , Carotid Stenosis/etiology , White Matter/diagnostic imaging , Magnetic Resonance Imaging , Cognitive Dysfunction/etiology , Cerebrovascular Circulation
3.
World Neurosurg ; 181: e1088-e1092, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37979682

ABSTRACT

BACKGROUND: Temporal changes in the volume of chronic subdural hematoma (CSDH) following middle meningeal artery (MMA) embolization vary. We aimed to determine whether CSDH density on computed tomography is related to hematoma resolution following particle MMA embolization. METHODS: Patients who underwent MMA embolization for CSDH were enrolled. The CSDHs were quantitatively divided into 2 hematoma groups based on the hematoma density at 1-week postembolization: low-density or high-density. The temporal change in the volume of CSDHs was then analyzed between the groups. RESULTS: Thirty patients were enrolled in this study. Three patients with high-density hematomas required rescue surgery. The hematoma volume was significantly lower in low-density hematomas than in high-density hematoma at 1-week (P = 0.006), 1-month (P = 0.003), and 2-month (P = 0.004) postembolization; although the volume converged to a similar value at 3-month (P > 0.05). There was a positive correlation between hematoma density at 1-week postembolization and percentage hematoma volume at 1-week and 1-month postembolization (P = 0.004 and P < 0.001, respectively), but no correlation was observed between hematoma density before MMA embolization and percentage hematoma volume at 1-week and 1-month postembolization (P = 0.54 and P = 0.17, respectively). CONCLUSIONS: Rapid resolution of CSDH following MMA embolization was associated with low hematoma density at 1-week postembolization. Based on hematoma density on computed tomography at 1-week postembolization, a 1-month follow-up would be sufficient in cases of low density, but a 3-month follow-up would be required in cases of high-density hematoma. Larger studies and clinical trials are needed to confirm our findings.


Subject(s)
Embolization, Therapeutic , Hematoma, Subdural, Chronic , Humans , Hematoma, Subdural, Chronic/therapy , Hematoma, Subdural, Chronic/surgery , Meningeal Arteries/diagnostic imaging , Meningeal Arteries/surgery , Embolization, Therapeutic/methods , Tomography, X-Ray Computed , Salvage Therapy
4.
Radiol Case Rep ; 18(11): 3856-3860, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37670927

ABSTRACT

Urgent carotid artery stenting (CAS) is effective for treatment-resistant cervical internal carotid artery dissection (CICAD). We experienced a 37-year-old woman who presented with sudden onset of cervical pain, blurred vision in the right eye, and numbness in the left upper and lower extremities. Due to neurological deterioration resulting from hemodynamic impairment, urgent CAS was performed under general anesthesia. Brain perfusion single-photon emission computed tomography performed immediately after CAS showed increased blood flow in the right hemisphere despite no evidence of hemorrhage or ischemic lesion on brain computed tomography (CT). Systolic blood pressure was therefore strictly controlled below 110 mm Hg perioperatively. However, the day after CAS, a follow-up CT showed intracerebral hemorrhage in the right temporal lobe. Urgent CAS in patients with progressive deterioration of hemodynamic impairment caused by CICAD may induce intracerebral hemorrhage due to cerebral hyperperfusion. Care should be taken to recognize and manage this phenomenon during the perioperative period.

5.
Heart Vessels ; 38(9): 1138-1148, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37029248

ABSTRACT

This study aimed to assess the predictors of spontaneous echocardiographic contrast (SEC) using left atrial appendage (LAA) findings in cardiac computed tomography (CT) of patients with atrial fibrillation (AF). We retrospectively analyzed cardiac CT findings of the LAA, including morphology, volume, and filling defects, of 641 patients who underwent transesophageal echocardiography (TEE) prior to pulmonary vein isolation (PVI) from January 6, 2013 through December 16, 2019 at our institution. We investigated potential associated factors that might be predictors of SEC using cardiac CT findings and computed a receiver operator characteristic, choosing a threshold value at which the likelihood of SEC could be predicted based on the LAA volume indexed for body size. SEC correlated significantly with indexed LAA volume (P < 0.001; odds ratio [OR], 1.31; 95% confidence interval [CI], 1.17-1.48) of 7.75 cm3/m2 or greater (sensitivity, 76.0%; specificity, 57.7%), LAA early filling defect (P = 0.005; OR, 2.72; 95% CI, 1.35-5.48), a history of persistent AF (P < 0.001; OR, 3.81; 95% CI, 1.86-7.80), and LAA flow velocity (P < 0.001; OR, 0.97; 95% CI, 0.96-0.99). Findings of LAA in cardiac CT can allow for the noninvasive estimation of SEC to determine the need for additional TEE investigation and the need to obtain additional information for risk stratification and management of thromboembolic events in patients with AF.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Humans , Echocardiography , Atrial Appendage/diagnostic imaging , Atrial Appendage/surgery , Atrial Fibrillation/complications , Atrial Fibrillation/surgery , Retrospective Studies , Echocardiography, Transesophageal , Male , Female , Middle Aged , Aged
6.
Nat Prod Res ; 37(3): 484-493, 2023 Feb.
Article in English | MEDLINE | ID: mdl-34749563

ABSTRACT

Two new octahydronaphthalene derivatives, trichodermic acid C (1) and trichodermic acid D (2), along with known analogs, trichodermic acid (3), trichodermic acid A (4) and trichodermic acid B (5), were isolated from an ethyl acetate extract of endophytic strain Trichoderma sp. HN-1.1. The structures of compounds 1 and 2 were elucidated using spectroscopic methods including UV, IR, HRESITOFMS, ECD, 1 D and 2 D NMR. The cytotoxic activity of the isolated compounds was evaluated on the rat hepatoma cell line H4IIE, using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. According to the results, only compound 3 showed a significant reduction of H4IIE cells from 75 to 21% (p < 0.01) with an IC50 value of 50% cell survival estimated as 143.1 µM, which indicated weak cytotoxic activity.


Subject(s)
Antineoplastic Agents , Trichoderma , Rats , Animals , Trichoderma/chemistry , Molecular Structure , Antineoplastic Agents/chemistry , Cell Line , Magnetic Resonance Spectroscopy
7.
Nat Prod Res ; 37(7): 1060-1066, 2023 Apr.
Article in English | MEDLINE | ID: mdl-34753360

ABSTRACT

A novel 2,3-epoxy naphthoquinol, named (6R,7R,8R)-theissenone A (1), possessing an oxatricyclo[5.4.0.03,5]undeca-trien-2-one skeleton, together with two known compounds, (6S,7R,8R)-theissenone (2) and arthrinone (3), were produced by an endophytic fungus, Arthrinium marii M-211, which was isolated from mangrove plants. The structure of 1, including the absolute stereochemistry, was elucidated by analysis of nuclear magnetic resonance (NMR) and mass spectrometry (MS) data and time-dependent density functional theory (TDDFT) calculations of electronic circular dichroism (ECD) spectra. Additionally, the absolute structure of 2 was deduced as a diastereomer of 1 using ECD spectral data analysis. Compounds 1, 2 and 3 exhibited cytotoxic activity against the H4IIE rat hepatoma cells, with IC50 values of 67.5, 46.6 and 13.4 µM, respectively.


Subject(s)
Ascomycota , Endophytes , Endophytes/chemistry , Ascomycota/chemistry , Magnetic Resonance Spectroscopy/methods , Mass Spectrometry , Molecular Structure , Circular Dichroism
8.
Radiol Case Rep ; 17(10): 3966-3970, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35991386

ABSTRACT

Objective: When performing endovascular interventions for supra-aortic vessels, the tortuous vascular anatomy observed in patients with atherosclerotic lesions often limits the ability to maintain a stable guiding catheter position. Here, we report a case of right vertebral artery (VA) stenosis treated with transfemoral stenting and discuss the utility of balloon-hooking technique using partially inflated balloon for stabilizing the balloon guiding catheter (BCG) in the supra-aortic vessel. Case presentation: A 74-year-old man who underwent right carotid artery stenting, coronary artery bypass grafting, and bilateral iliac artery stenting was admitted to our emergency department because of dizziness related to head movement. Computed tomography angiography revealed right VA origin stenosis and left subclavian artery (SA) occlusion. The patient underwent stenting of the right VA. After several unsuccessful cannulation attempts into the right VA through transradial access, transfemoral access was obtained through the left iliac stent. A 9-Fr BGC was navigated into the right SA. The balloon was partially inflated just distal to the first curve of the right SA and used as hook by pulling back until the proximal edge of the balloon was pushed distally by the lesser curvature of the SA, resulting in stabilization of the BGC and successful angioplasty and stent deployment at the VA stenosis. The patient's symptoms resolved completely, without any neurological deficits. Conclusions: Balloon-hooking technique using a partially inflated BGC is feasible for stabilizing the guiding catheter in tortuous supra-aortic vessel.

9.
J Neurosurg Case Lessons ; 4(2): CASE22152, 2022 Jul 11.
Article in English | MEDLINE | ID: mdl-35855009

ABSTRACT

BACKGROUND: Occlusion of the unilateral P1 segment can result in bilateral paramedian thalamic infarction in patients with anatomical variants of the bilateral paramedian thalamic artery arising from a single P1 segment. Despite the life-threatening presentation of bilateral paramedian thalamic stroke, timely diagnosis is often challenging. OBSERVATIONS: The authors herein describe 3 patients treated with endovascular intervention for occlusion of the unilateral P1 segment wherein the bilateral paramedian thalamic arteries arose. All patients were admitted to the authors' emergency department with sudden-onset coma and respiratory distress; however, initial computed tomography was unremarkable. Despite suspicion of basilar artery occlusion, vertebral and carotid angiography revealed occlusion of the unilateral P1 segment. All patients were successfully treated with endovascular intervention. Overall, 2 patients had favorable outcomes (modified Rankin scale [mRS] scores of 0 and 1), whereas in 1 patient, the mRS score reached a baseline score of 3. LESSONS: In patients with the variant of the bilateral paramedian thalamic artery arising from a single P1 segment, occlusion of the unilateral P1 segment can be life threatening; nevertheless, timely endovascular treatment is effective. Carotid and vertebral angiography, rather than magnetic resonance or computed tomography angiography, is useful for immediate and reliable diagnosis of the relatively small vascular lesions.

10.
J Neurosurg Case Lessons ; 3(21): CASE22116, 2022 May 23.
Article in English | MEDLINE | ID: mdl-35734235

ABSTRACT

BACKGROUND: The authors report a patient with sagittal sinus thrombosis that was resistant to reported endovascular treatments but successfully recanalized by dragging out the thrombus using a large balloon fixed with an aspiration catheter. OBSERVATIONS: A 57-year-old man presented with the persistent headache and a simple partial seizure. Diagnostic study with computed tomography and angiography demonstrated the superior sagittal sinus (SSS) thrombosis. Due to the neurological worsening even after systemic heparinization, the patient underwent mechanical thrombectomy. Despite six passes of stent retrievers and a large-bore aspiration catheter, functional recanalization was not achieved. Therefore, the so-called dental floss technique was attempted using a large compliant balloon catheter (Transform 7 × 7 mm). However, the balloon catheter just wobbled along the lesion without recanalization. To restrict the movement of the balloon catheter, the distal shaft of the balloon catheter was fixed with the aspiration catheter, and both the balloon and the aspiration catheter were slowly pulled to drag the thrombus out, resulting in recanalization of cortical veins as well as the SSS. LESSONS: Dragging the thrombus using a large balloon fixed with an aspiration catheter was a useful technique to retrieve sticky thrombus in the patients with the sinus thrombosis.

11.
Heart Vessels ; 37(8): 1436-1445, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35178607

ABSTRACT

The reduction in flow velocity within the left atrial appendage (LAAFV) is associated with a high risk of thromboembolic events. There has been few reports using sufficient sample size about the relationship between LAAFV reduction and LAA features on cardiac computed tomography (CT), including LAA volume and filling defects, in patients with atrial fibrillation (AF). We evaluated the predictors of reduced flow velocity within the LAA using the findings of cardiac CT in patients with AF. We retrospectively analysed the cardiac CT findings of the LAA of 440 patients who underwent transoesophageal echocardiography prior to pulmonary vein isolation between 12 February, 2013 and 16 December, 2019 at our institution. We investigated the potential predictors of reduced LAAFV and the difference in LAAFV between the different morphological types of the LAA. The reduced flow velocity within the LAA was significantly correlated with higher CHADS2 scores [P = 0.001; odds ratio (OR), 1.52; 95% confidence interval (CI), 1.18-1.95], early filling defect in the LAA (P = 0.001; OR, 3.36; 95% CI 1.63-6.93), and increased indexed LAA volume (P = 0.036; OR, 1.09; 95% CI 1.01-1.19). The LAA morphological type and AF type were not significant predictors of the LAAFV reduction. Increased LAA volume, early filling defects in the LAA, and higher CHADS2 scores were independent predictors of LAAFV reduction in patients with AF. Our findings suggest that cardiac CT findings might allow non-invasive estimation of reduced LAAFV. These CT-derived parameters may provide additional information for the risk stratification and management of thromboembolic events in patients with AF.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Thromboembolism , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Blood Flow Velocity , Echocardiography, Transesophageal , Humans , Retrospective Studies , Risk Factors , Thromboembolism/complications , Thromboembolism/prevention & control , Tomography, X-Ray Computed/methods
12.
J Am Soc Echocardiogr ; 35(6): 588-599, 2022 06.
Article in English | MEDLINE | ID: mdl-35091070

ABSTRACT

BACKGROUND: The exact relationship between tricuspid valve geometry and vena contracta (VC) morphology has pathophysiologic and mechanistic implications in patients with atrial functional tricuspid regurgitation (AF-TR). The aim of this study was to investigate tricuspid valve geometric and VC morphologic characteristics and compare them between AF-TR and ventricular functional tricuspid regurgitation (VF-TR) in sinus rhythm. METHODS: Transesophageal three-dimensional echocardiography data sets of the tricuspid valve were acquired in 439 patients with moderate to severe tricuspid regurgitation. Forty-eight patients with AF-TR and 48 with VF-TR in sinus rhythm matched for age, sex, body surface area, and VC area according to three-dimensional echocardiography-based pathogenic stratification were selected. VC morphology was determined by the ratio of anteroposterior to anterolateral-posteromedial diameter using color Doppler three-dimensional echocardiography. RESULTS: Patients with AF-TR had higher posterior annular perimeter/total annular perimeter ratios than patients with VF-TR in sinus rhythm (P < .001). Despite similar VC areas, patients with AF-TR had larger VC anteroposterior diameters and smaller VC anterolateral-posteromedial diameters, with resultant higher VC anteroposterior/anterolateral-posteromedial diameter ratios (P < .001). On multivariable analyses, posterior annular perimeter (coefficient = 0.013; 95% CI, 0.001 to 0.024) and posterior leaflet length/annular perimeter ratio (coefficient = -2.372; 95% CI, -3.591 to -1.154) were multivariable determinants of VC morphology in AF-TR. Additionally, posterior annular perimeter/total annular perimeter was strongly related to right atrial volume in AF-TR but not in VF-TR. CONCLUSIONS: Possible contributions to the initial mechanism of AF-TR include right atrial remodeling, predominant posterior annular dilatation, and insufficient adaptive posterior leaflet growth, which may have therapeutic implications in this setting.


Subject(s)
Echocardiography, Three-Dimensional , Tricuspid Valve Insufficiency , Dilatation , Heart Atria/diagnostic imaging , Humans , Tricuspid Valve/diagnostic imaging , Tricuspid Valve Insufficiency/diagnostic imaging
13.
J Cardiol ; 79(2): 211-218, 2022 02.
Article in English | MEDLINE | ID: mdl-34610891

ABSTRACT

BACKGROUND: Filling defects within the left atrial appendage (LAA) restricted to the early phase of computed tomography (CT) are not highly specific to the presence of thrombosis. The true significance of LAA early filling defects without thrombus remains uncertain. We evaluated the predictors of LAA early filling defects on echocardiography and cardiac CT findings in patients with atrial fibrillation (AF). METHODS: Cardiac CT findings of 641 patients with AF who underwent transesophageal echocardiography prior to pulmonary vein isolation from 6 January 2013 to 16 December 2019 at our institution were retrospectively analyzed. We investigated potential predictors of LAA early filling defects and computed the receiver operator characteristics, choosing a threshold value at which the likelihood of LAA early filling defects could be predicted. RESULTS: Early filling defects within the LAA correlated significantly with a history of persistent AF [p = 0.014; odds ratio (OR), 2.36; 95% confidence interval (CI), 1.19-4.66), low left ventricular ejection fraction (p = 0.009; OR, 2.62; 95% CI, 1.28-5.38), diminished LAA flow velocity (p < 0.001; OR, 0.97; 95% CI, 0.96-0.99) below 45.3 cm/s (sensitivity, 63.6%; specificity, 72.4%), and increased indexed LAA volume (p = 0.001; OR, 1.18; 95% CI, 1.07-1.30) ≥7.64 cm3/m2 (sensitivity, 70.5%; specificity, 69.0%). CONCLUSION: Early filling defects within the LAA on cardiac CT were associated with LAA function including risk factors for thrombus development, which could lead to noninvasive estimation of LAA function and additional information for risk stratification of thromboembolic events in patients with AF.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/complications , Atrial Fibrillation/diagnostic imaging , Echocardiography, Transesophageal , Humans , Retrospective Studies , Stroke Volume , Tomography, X-Ray Computed/methods , Ventricular Function, Left
14.
Intern Med ; 61(12): 1857-1861, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-34776488

ABSTRACT

Patients with constrictive pericarditis (CP) typically present with symptoms related to right-sided heart failure, such as cardiac ascites. Spontaneous bacterial peritonitis (SBP) usually arises in association with ascites secondary to hepatic cirrhosis. We herein report a rare case of CP in which SBP developed due to cardiac ascites, even in the absence of cirrhosis. In this case, pericardiectomy improved both the hemodynamics and the ascites, while therapy with diuretics alone was insufficient. It is important to consider SBP in the differential diagnosis when any abdominal symptoms or an inflammatory response is found in patients with heart failure and cardiac ascites.


Subject(s)
Chylous Ascites , Heart Failure , Pericarditis, Constrictive , Peritonitis , Ascites/complications , Ascites/diagnostic imaging , Chylous Ascites/complications , Heart Failure/complications , Humans , Liver Cirrhosis/complications , Pericardiectomy/adverse effects , Pericarditis, Constrictive/complications , Pericarditis, Constrictive/diagnostic imaging , Pericarditis, Constrictive/surgery , Peritonitis/complications , Peritonitis/diagnosis
15.
J Cardiol Cases ; 24(6): 280-283, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34917210

ABSTRACT

Papillary fibroelastoma (PFE) is a cardiac tumor that is mainly found on the heart valve and the endocardium of the atria and ventricles. Symptoms such as stroke and myocardial infarction are usually caused by embolization of either the tumor itself or associated thrombus. PFE is known to originate mainly from the left side of the heart, and these cases are-in principle-candidates for surgical resection. On the other hand, cases in which PFE originates from the right side of the heart are rare and reports are limited; thus, the surgical indication is unclear. We herein report a case of symptomatic PFE originating from the tricuspid valve of the heart. In this case, contrast enhanced computed tomography did not show pulmonary embolism; however, lung perfusion scintigraphy showed multiple perfusion defects. The patient was treated by anticoagulant therapy followed by surgical resection. Thereafter, the symptoms disappeared and the multiple perfusion defects improved on lung perfusion scintigraphy, demonstrating the efficacy of the anticoagulant therapy and surgical resection for PFE in the right side of the heart. .

16.
Dalton Trans ; 50(41): 14611-14617, 2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34605516

ABSTRACT

Four types of tris-chelate ruthenium complexes bearing acetylacetonato (acac) and tropolonato (trop) ligands were synthesized and optically resolved into Δ and Λ isomers: [Ru(acac)3] (Ru-0), [Ru(acac)2(trop)] (Ru-1), [Ru(acac)(trop)2] (Ru-2), and [Ru(trop)3] (Ru-3). Chiral HPLC chromatograms, electronic circular dichroism (ECD), and vibrational circular dichroism (VCD) of the four ruthenium complexes were systematically investigated. As a result, the absolute configurations of the newly prepared enantiomeric complexes Ru-2 and Ru-3 were determined. For the case of Ru-2, its absolute configuration was also confirmed by single crystal X-ray diffraction analysis. The ECD changes upon chemical oxidation were further investigated for the four complexes. An ECD change in enantiomeric Ru-1 was observed upon oxidation, but the oxidized species soon returned to the neutral state within a few minutes. Enantiomers of Ru-3 also showed explicit ECD changes upon oxidation. Further, the lifetime of the oxidized state was the longest among the four investigated complexes, whereas they racemized in solution at room temperature. In contrast, the enantiomers of heteroleptic complexes (Ru-1 and Ru-2) concurrently exhibited ECD changes, relatively long lifetime of the oxidized state, and nil or quite slow racemization behavior. The coexistence of acac and trop ligands was key to making the competing factors compatible in the resultant ruthenium complexes.

17.
Dalton Trans ; 50(38): 13256-13263, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34608912

ABSTRACT

The coordinatively unsaturated bis-chelated iridium(III) complex, [Ir(2-Bubzq)2Cl] (2-BubzqH = 2-butyl-benzo[h]quinoline), denoted as complex 1, was obtained by reacting iridium(III) trichloride with 2-BubzqH in a 1 : 2 molar ratio. The results were in contrast to the common view that a chlorine-bridged dimer, [Ir(L)2Cl]2 (L = bis-chelate ligand), is formed under the corresponding conditions. A single-crystal X-ray diffraction structural analysis revealed that complex 1 has a five-coordinate geometry with a distorted square pyramidal configuration. The optical resolution of complex 1 was measured chromatographically on a chiral column, yielding Δ and Λ as enantiomers. The resolved enantiomers were stable enough against racemization in CDCl3 as confirmed by the vibrational circular dichroism measurements. Complex 1 reacted with carbon monoxide (CO) to give [Ir(2-Bubzq)2(CO)Cl] and with 1,10-phenanthroline (phen) to give [Ir(2-Bubzq)2(phen)]Cl within a minute with its absolute configuration (ΔΛ chirality) maintained.

18.
J Phys Chem Lett ; 12(32): 7733-7737, 2021 Aug 19.
Article in English | MEDLINE | ID: mdl-34355918

ABSTRACT

The supramolecular chirality of the hindwing of Anomala albopilosa (male) was investigated using a microscopic vibrational circular dichroism (VCD) system, denoted as MultiD-VCD. The source of intense infrared (IR) light for the system was a quantum cascade laser. Two-dimensional maps of IR and VCD spectra were taken by scanning the surface area (ca. 2 mm × 2 mm) of the insect hindwing tissue. The spectra ranged from 1500 to 1700 cm-1, and the maps have a spatial resolution of 100 µm. The distribution of proteins, including their supramolecular structures, was analyzed from the location-dependent spectral shape of the VCD bands assigned to amides I and II. The results revealed that the hindwing consists of segregated domains of proteins with different secondary structures: an α-helix (in one part of the membrane), a hybrid of α-helix and ß-sheet (in another part of the membrane), and a coil (in a vein).


Subject(s)
Insect Proteins/chemistry , Wings, Animal/chemistry , Animals , Circular Dichroism/methods , Coleoptera , Male , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Stereoisomerism , Vibration
19.
Dalton Trans ; 50(24): 8506-8511, 2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34052843

ABSTRACT

In this study, we report the emissive properties of a heteroleptic cyclometalated Ir(iii) complex, [Ir(bzq)2(PBO)] (bzqH = benzo[h]quinoline; PBOH = 2-(2-hydroxyphenyl)benzoxazole). The complex, [Ir(C^N)2(N^O)], was synthesised and optically resolved using a chiral column. Two geometrical isomers, trans-(N,N) and cis-(N,N) isomers, were obtained as the major and minor products in an enantiopure form, respectively. Their molecular structures were determined using single crystal X-ray analysis. In the crystalline states, the intermolecular C-Hπ interaction between PBO- and an H atom in bzq- was the main factor influencing molecular packing. When the complexes were dissolved in CH2Cl2 and excited at 430 nm under N2 atmosphere, yellow (λmax = 550 nm) and orange emissions (λmax = 570 nm) were observed for the trans-(N,N) and cis-(N,N) isomers, respectively, with the quantum yield higher for the former than the latter.

20.
Echocardiography ; 38(6): 932-942, 2021 06.
Article in English | MEDLINE | ID: mdl-33983660

ABSTRACT

BACKGROUND: Left ventricular (LV) outflow tract (LVOT) obstruction increases mortality in patients undergoing transcatheter mitral valve implantation (TMVI) in degenerated bioprostheses, annuloplasty rings, and native mitral valves. We aimed to evaluate the LVOT area after TMVI using 3-dimensional (3D) transesophageal echocardiography (TEE) and to investigate the preprocedural cardiac geometry that affects the LVOT area after TMVI. METHODS: We retrospectively reviewed echocardiography data in 43 patients who had TMVI. A change in pressure gradient across LVOT from before to after TMVI (∆PG) and postprocedure 3D LVOT cross-sectional area at the level of the most distal portion of the mitral valve stent that was closest to the LV apex were assessed as evidence of LVOT narrowing. RESULTS: Transcatheter mitral valve implantation with the use of balloon-expandable valve system was performed for 24 bioprostheses, 7 annuloplasty rings, and 12 native valves. Compared to patients without increase in LVOT gradient (∆PG <10 mm Hg; n = 33), patients with increase in LVOT gradient (∆PG ≥10 mm Hg; n = 10) had smaller LV end-systolic volume (LVESV), greater LV ejection fraction (LVEF), and smaller aorto-mitral (AM) angle. The LVOT area at the valve stent distal edge showed strong association with ∆PG (r = -.68, P < .0001). Only a small AM angle was associated with a small LVOT area at the valve stent distal edge on multivariable analysis, independent of LVESV and LVEF. CONCLUSION: Small LV size, preserved LVEF, and small AM angle were associated with LVOT narrowing. 3D-derived AM angle might be independently associated with LVOT narrowing in patients undergoing transcatheter mitral valve-in-valve, valve-in-ring, and valve-in-native valve implantation, independent of LVESV and LVEF.


Subject(s)
Heart Valve Prosthesis Implantation , Heart Valve Prosthesis , Mitral Valve Insufficiency , Transcatheter Aortic Valve Replacement , Ventricular Outflow Obstruction , Cardiac Catheterization , Echocardiography, Transesophageal , Humans , Mitral Valve/diagnostic imaging , Mitral Valve/surgery , Mitral Valve Insufficiency/diagnostic imaging , Mitral Valve Insufficiency/surgery , Retrospective Studies , Treatment Outcome
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