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1.
Chem Commun (Camb) ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007876

RESUMEN

Assembly of coordination networks from Cd(II) and a multi-interactive hexaazaphenalene-based ligand was successfully modulated using magnetic fields and thermodynamic control. A relatively weak field of only 320 mT was able to perturb the orientational distribution of the ligand in solution nudging the reaction down a different path. The underlying mechanism involved alignment of the ligands along the field lines, which was supported by DFT calculations. This crystallization technique could be extended to the synthesis of other networks and facilitate a deeper exploration of the reaction landscapes.

2.
J Radiat Res ; 65(4): 532-539, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38923425

RESUMEN

We sought to identify potential evidence-practice gaps in palliative radiotherapy using quality indicators (QIs), previously developed using a modified Delphi method. Seven QIs were used to assess the quality of radiotherapy for bone metastases (BoM) and brain metastases (BrM). Compliance rate was calculated as the percentage of patients for whom recommended medical care was conducted. Random effects models were used to estimate the pooled compliance rates. Of the 39 invited radiation oncologists, 29 (74%) from 29 centers participated in the survey; 13 (45%) were academic and 16 (55%) were non-academic hospitals. For the QIs, except for BoM-4, the pooled compliance rates were higher than 80%; however, for at least some of the centers, the compliance rate was lower than these pooled rates. For BoM-4 regarding steroid use concurrent with radiotherapy for malignant spinal cord compression, the pooled compliance rate was as low as 32%. For BoM-1 regarding the choice of radiation schedule, the compliance rate was higher in academic hospitals than in non-academic hospitals (P = 0.021). For BrM-3 regarding the initiation of radiotherapy without delay, the compliance rate was lower in academic hospitals than in non-academic hospitals (P = 0.016). In conclusion, overall, compliance rates were high; however, for many QIs, practice remains to be improved in at least some centers. Steroids are infrequently used concurrently with radiotherapy for malignant spinal cord compression.


Asunto(s)
Cuidados Paliativos , Indicadores de Calidad de la Atención de Salud , Humanos , Encuestas y Cuestionarios , Neoplasias Encefálicas/radioterapia , Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Radioterapia , Adhesión a Directriz
3.
Ultrasonics ; 141: 107346, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38820872

RESUMEN

Ultrasound tomography (UT) of bubbly two-phase flows using machine learning (ML) was investigated by performing two-dimensional ultrasound numerical simulations using a finite element method simulator. Studies on UT for two-phase flow measurements have been conducted only for some bubbles. However, in an actual bubbly flow, numerous bubbles are complexly distributed in the cross-section of the flow channel. This limitation of previous studies originates from the transmission characteristics of ultrasound waves through a medium. The transmission characteristics of ultrasound waves differ from those of other probe signals, such as radiation, electrical, and optical signals. This study evaluated the feasibility of combining UT with ML for predicting dense bubble distributions with up to 20 bubbles (cross-sectional average void fraction of approximately 0.29). We investigated the effects of the temporal length of the received waveform and the number of sensors to optimize the system on the prediction performance of the bubble distribution. The simultaneous driving of the installed sensors was simulated to reduce the measurement time for the entire cross-section and verify the method's applicability. Thus, it was confirmed that UT using ML has sufficient prediction performance, even for a complex bubble distribution with many bubbles, and that the cross-sectional average void fraction can be predicted with high accuracy.

4.
Diabetol Int ; 15(2): 253-261, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38524941

RESUMEN

Background: Numerous studies demonstrated the risk factors for urological complications in patients with diabetes before sodium-glucose co-transporter 2 inhibitor (SGLT2i) became commercially available. This study aimed to comprehensively investigate urological characteristics in patients with type 2 diabetes (T2DM) after SGLT2i became commercially available. Methods: We examined 63 outpatients with T2DM suspected of bacteriuria based on urinary sediment examinations. Urine cultures were performed, and lower urinary tract symptoms (LUTS) were assessed via questionnaires. Patients with bacteriuria were assessed using ultrasonography to measure post-void residual volume (PVR). Utilizing demographic and laboratory data, a random forest algorithm predicted LUTS, bacteriuria, and symptomatic bacteriuria (SB). Results: Thirty-two patients had LUTS and 31 had bacteriuria. High-density lipoprotein cholesterol level was crucial in predicting LUTS, while age was crucial in predicting bacteriuria. In predicting SB among patients with bacteriuria, creatinine level and estimated glomerular filtration rate were crucial. Our models had high predictive accuracy for LUTS (area under the curve [AUC] = 0.846), followed by bacteriuria (AUC = 0.770) and SB (AUC = 0.938) in receiver operating characteristic curve analysis. These predictors were previously reported as risk factors for urological complications. Although SGLT2i use was not an important predictor in our study, all SGLT2i users with bacteriuria had SB and exhibited higher PVR compared to non-SGLT2i users with bacteriuria. Conclusion: This study's random forest model highlighted distinct essential predictors for each urological condition. The predictors were consistent before and after SGLT2i became commercially available. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-023-00687-1.

5.
Nat Commun ; 15(1): 81, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167264

RESUMEN

We introduce a versatile metal-organic framework (MOF) for encapsulation and immobilization of various guests using highly ordered internal water network. The unique water-mediated entrapment mechanism is applied for structural elucidation of 14 bioactive compounds, including 3 natural product intermediates whose 3D structures are clarified. The single-crystal X-ray diffraction analysis reveals that incorporated guests are surrounded by hydrogen-bonded water networks inside the pores, which uniquely adapt to each molecule, providing clearly defined crystallographic sites. The calculations of host-solvent-guest structures show that the guests are primarily interacting with the MOF through weak dispersion forces. In contrast, the coordination and hydrogen bonds contribute less to the total stabilization energy, however, they provide highly directional point interactions, which help align the guests inside the pore.

6.
J Am Chem Soc ; 146(3): 1832-1838, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206810

RESUMEN

Isomerism in covalent organic frameworks (COFs) has scarcely been known. Here, for the first time we show 3D COFs with three framework isomers or polymorphs constructed from the same building blocks. All isomers were obtained as large (>10 µm) crystals; although their crystal shapes were distinctly different, they showed identical FT-IR and solid-state NMR spectra. Our structural analyses revealed unprecedented triple isomerism in 3D COFs (noninterpenetrated dia, qtz, and 3-fold interpenetrated dia-c3 nets). Furthermore, this Communication reports the first known COF with qtz topology for which the structure determination was based on Rietveld analysis. We achieved triple framework isomerism by reticulating a tetrahedral building block with a flexible junction and a linear building block with PEO side chains and by varying solution compositions. Our energy calculations, along with the discovery of interisomer transition, revealed that the isomer with qtz topology was a kinetic isomer. Thus, this simple yet little-explored concept of reticulating only flexible building blocks is an effective pathway to significantly broaden the diversity of 3D COFs, which have been proposed for a myriad of applications.

7.
Adv Sci (Weinh) ; 11(2): e2307417, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37985922

RESUMEN

A coordination network containing isolated pores without interconnecting channels is prepared from a tetrahedral ligand and copper(I) iodide. Despite the lack of accessibility, CO2 is selectively adsorbed into these pores at 298 K and then retained for more than one week while exposed to the atmosphere. The CO2 adsorption energy and diffusion mechanism throughout the network are simulated using Matlantis, which helps to rationalize the experimental results. CO2 enters the isolated voids through transient channels, termed "magic doors", which can momentarily appear within the structure. Once inside the voids, CO2 remains locked in limiting its escape. This mechanism is facilitated by the flexibility of organic ligands and the pivot motion of cluster units. In situ powder X-ray diffraction revealed that the crystal structure change is negligible before and after CO2 capture, unlike gate-opening coordination networks. The uncovered CO2 sorption and retention ability paves the way for the design of sorbents based on isolated voids.

8.
Nihon Shokakibyo Gakkai Zasshi ; 120(11): 912-919, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37952966

RESUMEN

We investigated the findings of rectoanal lesions in 190 patients who underwent colon capsule endoscopy (CCE) at our hospital. Internal hemorrhoids were observed in 70 (36.8%) patients and rectal polyps in 19 (10%) patients. When conventional endoscopy (colonoscopy and double balloon endoscopy) was considered the gold standard, the sensitivity and specificity of rectal polyps were 75% and 93.4%, respectively, and those of internal hemorrhoids were 88.9% and 92.7%, respectively. The prevalence of constipation was significantly higher in the false-negative group for internal hemorrhoids, and the colonic transit time was significantly shorter in the false-negative and false-positive groups for rectal polyps. No adverse events occurred in any of the patients. CCE might be a useful and safe examination method for rectoanal lesions.


Asunto(s)
Endoscopía Capsular , Pólipos del Colon , Neoplasias Colorrectales , Hemorroides , Neoplasias del Recto , Humanos , Endoscopía Capsular/efectos adversos , Endoscopía Capsular/métodos , Pólipos del Colon/diagnóstico , Pólipos del Colon/etiología , Pólipos del Colon/patología , Hemorroides/etiología , Hemorroides/patología , Estudios Prospectivos , Colonoscopía/métodos , Colon , Neoplasias Colorrectales/diagnóstico
9.
Commun Chem ; 6(1): 245, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37945657

RESUMEN

Photophysical properties of benzil (1,2-diphenylethane-1,2-dione) and its derivatives in the crystal state have recently attracted much attention. However, the study of substituted benzils has mostly been limited to para-substituted derivatives, which did not induce a significant effect on the emission wavelength compared to pristine benzil. The effects of ortho- and meta-substituents on the photophysical properties in the crystal state have not been investigated so far. Our recently developed organocatalytic pinacol coupling of substituted benzaldehydes allowed us to prepare various ortho-, meta-, and para-substituted benzil derivatives and to investigate their luminescence properties. Ortho- and meta-substituents affected the electronic states of benzils in the crystal state, resulting in differences in their luminescence properties. The luminescence wavelength and type, i.e., phosphorescence or fluorescence, were altered by these substituents. Fast self-recovering phosphorescence-to-phosphorescence mechanochromism by the para-CF3 substituent at room temperature was also discovered.

10.
Chem Commun (Camb) ; 59(87): 13026-13029, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37842839

RESUMEN

This study demonstrates the C-N coupling of tryptophan with azoles, promoted by an in situ-generated iodine-based oxidant. The protocol was successfully applied to the selective modification of tryptophan in nonprotected polypeptide bearing oxidatively sensitive residues in acidic aqueous media. The present method allows the attachment of reactive handles to polypeptides and the peptide stapling.

12.
13.
Curr Oncol ; 30(9): 8092-8110, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37754502

RESUMEN

A recent approach to radiotherapy for prostate cancer is the administration of high doses of radiation to the prostate while minimizing the risk of side effects. Thus, image-guided radiotherapy utilizes advanced imaging techniques and is a feasible strategy for increasing the radiation dose. New radioactive particles are another approach to achieving high doses and safe procedures. Prostate brachytherapy is currently considered as a combination therapy. Spacers are useful to protect adjacent organs, specifically the rectum, from excessive radiation exposure.


Asunto(s)
Neoplasias de la Próstata , Radioterapia de Intensidad Modulada , Masculino , Humanos , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/métodos , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/etiología , Próstata/efectos de la radiación , Recto/efectos de la radiación
14.
J Med Imaging Radiat Sci ; 54(4): 595-602, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37481374

RESUMEN

INTRODUCTION: The efficacy of radiotherapy for symptomatic relief of malignant psoas syndrome (MPS) remains unknown because there are limited publications with high level evidence, including analyses with sufficient number of cases, clinical trials, and systematic reviews about radiotherapy for MPS. We aimed to investigate the characteristics of and symptom relief rates in patients treated with radiotherapy for MPS in palliative intent. METHODS: In this single-center retrospective study, we analyzed data of 22 consecutive patients treated with radiotherapy for MPS at our institution in Japan between 2012 and 2022. We recorded patient characteristics, including primary site, invasion pattern, recognition of MPS by the attending physician, radiation regimen, biological effective dose with α/ß = 10 Gy (BED10), and adverse events. Since no objective evaluation index for palliative radiotherapy for non-bone metastases has been established, we modified and used an International Consensus on Palliative Radiotherapy Endpoint, which was originally used for bone metastases, to evaluate symptom relief in the present retrospective study. "Response" was defined as symptom relief described in medical records or the use of analgesic medications reduced by ≥25% within 3 months post-initiation of radiotherapy. RESULTS: Genitourinary organs (41%) were the most common primary-tumor sites. MPS was caused by metastasis in the iliopsoas muscle in 14 patients (64%) and by direct invasion of the primary tumor in eight patients (36%). Since the optimal radiation dose for MPS has not been established, the radiation dose varied from low dose, which are used in palliative radiotherapy for painful bone metastases, to high dose with conventional fraction using 1.8 to 2 Gy per fraction, with a median BED10 of 48 Gy (range, 10.6-79.2 Gy). Fifteen patients (68%) achieved a response. No acute nor late adverse events of grade 2 or higher, according to Common Terminology Criteria for Adverse Events version 5.0, were reported during the observation period. CONCLUSION: Radiotherapy for symptomatic MPS might be an effective treatment option with a high response rate (68%) and minimal adverse events. Since the present study is a retrospective study with small number of cases, a prospective study with a larger sample size is required.


Asunto(s)
Neoplasias Óseas , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Dosificación Radioterapéutica , Neoplasias Óseas/radioterapia , Resultado del Tratamiento
15.
Breast Cancer ; 30(2): 282-292, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36528759

RESUMEN

BACKGROUND: There is a lack of data on combined radiotherapy (RT) and cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i) risk factors and toxicity. This study aimed to assess the incidence of and risk factors for non-hematologic toxicities in patients treated with combined RT and CDK4/6i using dose-volume parameter analysis. METHODS: We conducted a retrospective multicenter cohort study of patients with metastatic breast cancer receiving RT within 14 days of CDK4/6i use. The endpoint was non-hematologic toxicities. Patient characteristics and RT treatment planning data were compared between the moderate or higher toxicities (≥ grade 2) group and the non-moderate toxicities group. RESULTS: Sixty patients were included in the study. CDK4/6i was provided at a median daily dose of 125 mg and 200 mg for palbociclib and abemaciclib, respectively. In patients who received concurrent RT and CDK4/6i (N = 29), the median concurrent prescribed duration of CDK4/6i was 14 days. The median delivered RT dose was 30 Gy and 10 fractions. The rate of grade 2 and 3 non-hematologic toxicities was 30% and 2%, respectively. There was no difference in toxicity between concurrent and sequential use of CDK4/6i. The moderate pneumonitis group had a larger lung V20 equivalent dose of 2 Gy per fraction and planning target volume than the non-moderate pneumonitis group. CONCLUSIONS: Moderate toxicities are frequent with combined RT and CDK4/6i. Caution is necessary concerning the combined RT and CDK4/6i. Particularly, reducing the dose to normal organs is necessary for combined RT and CDK4/6i.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Incidencia , Estudios de Cohortes , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/uso terapéutico , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico
18.
Kyobu Geka ; 75(6): 418-421, 2022 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-35618686

RESUMEN

A 85-year old male with hoarseness due to distal aortic arch aneurysm underwent zone 1 thoracic endovascular aortic repair( TEVAR) with two-debranching at our hospital. Five years after the TEVAR (90 years old), computed tomography( CT) revealed typeⅠa endoleak due to migration of proximal end of the graft. Anatomically, additional TEVAR was impossible. To minimize the invasiveness, a two-stage surgery was planned. First, under deep hypothermic circulatory arrest, the ascending aorta was replaced with the brachiocephalic artery reconstruction and insertion of a stented vascular prosthesis distally through partial sternotomy to preserve the debranching bypass. Six days after the surgery, a transcatheter stent graft was placed from the stented vascular prosthesis to the native descending aorta. Postoperative course was uneventful, and CT scan showed no endoleak.


Asunto(s)
Aneurisma de la Aorta Torácica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Anciano de 80 o más Años , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Endofuga/diagnóstico por imagen , Endofuga/etiología , Endofuga/cirugía , Humanos , Masculino , Nonagenarios , Resultado del Tratamiento
19.
J Cardiothorac Surg ; 17(1): 95, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35505355

RESUMEN

BACKGROUND: The optimal treatment for aortic thrombus remains to be determined, but surgical treatment is indicated when there is a risk for thromboembolism. CASE PRESENTATION: A 47-year-old male presented with weakness in his left arm upon awakening. Contrast-enhanced computed tomography and transesophageal echocardiography revealed a mobile pedunculated object suggestive of a thrombus arising from the ascending aorta and extending to the left common carotid artery. It was removed under hypothermic circulatory arrest and direct cannulation of the left carotid artery to avoid carotid thromboembolism. Histopathological examination revealed that the object was a thrombus. The patient had an uneventful postoperative course and was discharged 9 days after surgery. CONCLUSION: When a thrombus in the aortic arch extends to the neck arteries, direct cannulation of the neck arteries with selective cerebral perfusion via cervical incision is a useful technique.


Asunto(s)
Tromboembolia , Trombosis , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/cirugía , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/cirugía , Humanos , Masculino , Persona de Mediana Edad , Perfusión/métodos , Trombosis/diagnóstico por imagen , Trombosis/cirugía
20.
Nanoscale ; 14(22): 7974-7979, 2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35470826

RESUMEN

In photoluminescence (PL) quenching and triplet fusion upconversion experiments with fluorescent organic-molecule quenchers, it was revealed that a rod-shaped, phosphine- and thiolate-protected biicosahedral Au25 cluster (a representative di-superatomic molecule) exhibits only phosphorescence, not fluorescence, at room temperature with an intersystem crossing quantum yield of almost 100%. By virtue of these photophysical properties, this cluster can be used as a triplet sensitizer that undergoes direct singlet-triplet transitions in the near-infrared (NIR) region (730-900 nm), inducing photon upconversion from NIR to visible light.

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