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1.
Int J Biol Macromol ; 266(Pt 1): 130990, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38508553

RESUMO

This study investigated the effect of polymer blending of microbially produced poly[(R)-lactate-co-(R)-3-hydroxybutyrate] copolymers (LAHB) with poly(lactate) (PLA) on their mechanical, thermal, and biodegradable properties. Blending of high lactate (LA) content and high molecular weight LAHB significantly improved the tensile elongation of PLA up to more than 250 % at optimal LAHB composition of 20-30 wt%. Temperature-modulated differential scanning calorimetry and dynamic mechanical analysis revealed that PLA and LAHB were immiscible but interacted with each other, as indicated by the mutual plasticization effect. Detailed morphological characterization using scanning probe microscopy, small-angle X-ray scattering, and solid-state NMR confirmed that PLA and LAHB formed a two-phase structure with a characteristic length scale as small as 20 nm. Because of mixing in this order, the polymer blends were optically transparent. The biological oxygen demand test of the polymer blends in seawater indicated an enhancement of PLA biodegradation during biodegradation of the polymer blends.

2.
Angew Chem Int Ed Engl ; : e202403886, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545689

RESUMO

The photocatalytic reduction of carbon dioxide (CO2) represents an attractive approach for solar-energy storage and leads to the production of renewable fuels and valuable chemicals. Although some osmium (Os) photosensitizers absorb long wave-lengths in the visible-light region, a self-photosensitized, mono-nuclear Os catalyst for red-light-driven CO2 reduction has not yet been exploited. Here, we discovered that the introduction of an Os metal to a PNNP-type tetradentate ligand resulted in the absorption of light with longer-wavelength (350-700 nm) and that can be applied to a panchromatic self-photosensitized catalyst for CO2 reduction to give mainly carbon monoxide (CO) with a total turnover number (TON) of 625 under photoirradiation (λ ≥ 400 nm). CO2 photoreduction also proceeded under irradiation with blue (λ0 = 405 nm), green (λ0 = 525 nm), or red (λ0 = 630 nm) light to give CO with >90% selectivity. The quantum efficiency using red light was determined to be 12% for the generation of CO. A catalytic mechanism is proposed based on the detection of intermediates using various spectroscopic techniques, including transient absorption, electron paramagnetic resonance, and UV-vis spectroscopy.

3.
Kyobu Geka ; 77(1): 38-41, 2024 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-38459844

RESUMO

Off-pump totally-endoscopic surgery for atrial fibrillation is reported. This procedure is also called the Wolf-Ohtsuka procedure or totally thoracoscopic maze (TT-maze) surgery. It is a minimally invasive left atrial appendage management and surgical ablation. The wound is limited to that required for port placement, and the patient recovers quickly. Advantages over WATCHMAN include the that it can be applied regardless of the size of the left atrial appendage, can be performed even if there is a thrombus at the tip of the left atrial appendage, and no wound or device comes on the endocardial side. Advantages over catheter ablation is the potential for embolism prevention by simultaneously performing ablation and the left atrial appendage management. The tips and techniques for this procedure are also described here.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Humanos , Fibrilação Atrial/cirurgia , Apêndice Atrial/cirurgia , Resultado do Tratamento , Toracoscopia/métodos , Ablação por Cateter/métodos
4.
Anticancer Res ; 44(3): 1271-1279, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38423657

RESUMO

BACKGROUND/AIM: Sequential therapy using chemotherapy and subsequent immune checkpoint inhibitor (ICI) treatment prolongs the survival of patients with advanced urothelial carcinoma (UC). However, no comparison data for oncological outcome between pembrolizumab and avelumab has been reported. Thus, we compared oncological outcomes between pembrolizumab as second-line therapy and maintenance avelumab therapy in patients with advanced UC. PATIENTS AND METHODS: We retrospectively evaluated patients with advanced UC treated with pembrolizumab or avelumab between January 2018 and February 2023. We compared oncological outcomes after adjusting for patient characteristics. Immune-related adverse events (AEs) in each group were evaluated using the Common Terminology Criteria for Adverse Events. RESULTS: There were 186 and 44 patients in the pembrolizumab- and avelumab-treated cohorts, respectively. After propensity score matching, 43 patients from each group were selected and analyzed. Median progression-free survival from the initiation of pembrolizumab and avelumab treatments was 126 and 139 days, respectively (log-rank test, p=0.625). Median overall survival in the pembrolizumab and avelumab cohorts were 658 days and not reached, respectively (log-rank test, p=0.249). Thirty-eight (20.4%) and 14 (31.8%) all-grade immune-related AEs were observed in 186 pembrolizumab- and 44 avelumab-treated patients, respectively (chi-squared test, p=0.112). Regarding endocrine-related AEs, 12 (6.5%) and none (0%) were observed in pembrolizumab- and avelumab-treated patients, respectively (Fisher's exact probability test, p=0.129). CONCLUSION: Pembrolizumab and maintenance avelumab therapy provide equivalent oncological outcomes in patients with advanced UC. Although no significant difference was observed, there might be a potential risk of higher endocrine-related AEs due to pembrolizumab compared to avelumab maintenance therapy.


Assuntos
Anticorpos Monoclonais Humanizados , Antineoplásicos Imunológicos , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Platina/uso terapêutico , Estudos Retrospectivos , Neoplasias Urológicas/patologia , Antineoplásicos Imunológicos/uso terapêutico
5.
J Phys Chem Lett ; 15(8): 2184-2192, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38373145

RESUMO

High-order harmonic generation (HHG) in gases is frequently used nowadays to produce attosecond pulses and coherent radiation in the visible-to-soft X-ray spectral range. HHG in solids is a natural extension of the idea of HHG in gases, and its first observation about ten years ago opened the door to investigations on attosecond electron dynamics in solids and the development of solid-state attosecond light sources. The common process in both types of HHG is nonlinear photocarrier generation, and thus, transitions between different bands (interband transitions) are always important for HHG. As well, in the case of solids, the transitions within a band (intraband transitions) also need to be considered, because efficient carrier acceleration is possible due to them. This Perspective focuses on experimental findings that show how intraband transitions can be controlled because such an understanding will be essential in the development of unique optoelectronics that can operate at petahertz frequencies.

7.
Int Psychogeriatr ; 36(1): 64-77, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36714996

RESUMO

OBJECTIVES: We aimed to investigate the association between very late-onset schizophrenia-like psychosis (VLOSLP), a schizophrenia spectrum disorder with an onset of ≥60 years, and Alzheimer's disease (AD) using biomarkers. DESIGN: Retrospective cross-sectional study. SETTING: Neuropsychology clinic of Osaka University Hospital in Japan. PARTICIPANTS: Thirty-three participants were classified into three groups: eight AD biomarker-negative VLOSLP (VLOSLP-AD), nine AD biomarker-positive VLOSLP (VLOSLP+AD), and sixteen amnestic mild cognitive impairment due to AD without psychosis (aMCI-P+AD) participants. MEASUREMENTS: Phosphorylated tau levels in the cerebrospinal fluid and 18F-Florbetapir positron emission tomography results were used as AD biomarkers. Several scales (e.g. the Mini-Mental State Examination (MMSE), Wechsler Memory Scale-Revised (WMS-R) Logical Memory (LM) I and II, and Neuropsychiatric Inventory (NPI)-plus) were conducted to assess clinical characteristics. RESULTS: Those in both VLOSLP-AD and +AD groups scored higher than those in aMCI-P+AD in WMS-R LM I. On the other hand, VLOSLP+AD participants scored in between the other two groups in the WMS-R LM II, with only VLOSLP-AD participants scoring significantly higher than aMCI-P+AD participants. There were no significant differences in sex distribution and MMSE scores among the three groups or in the subtype of psychotic symptoms between VLOSLP-AD and +AD participants. Four VLOSLP-AD and five VLOSLP+AD participants harbored partition delusions. Delusion of theft was shown in two VLOSLP-AD patients and five VLOSLP+AD patients. CONCLUSION: Some VLOSLP patients had AD pathology. Clinical characteristics were different between AD biomarker-positive and AD biomarker-negative VLOSLP, which may be helpful for detecting AD pathology in VLOSLP patients.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Doença de Alzheimer/psicologia , Estudos Transversais , Estudos Retrospectivos , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Disfunção Cognitiva/psicologia , Biomarcadores , Peptídeos beta-Amiloides/líquido cefalorraquidiano
8.
Neural Netw ; 171: 242-250, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38101292

RESUMO

Dementia and mild cognitive impairment (MCI) represent significant health challenges in an aging population. As the search for noninvasive, precise and accessible diagnostic methods continues, the efficacy of electroencephalography (EEG) combined with deep convolutional neural networks (DCNNs) in varied clinical settings remains unverified, particularly for pathologies underlying MCI such as Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and idiopathic normal-pressure hydrocephalus (iNPH). Addressing this gap, our study evaluates the generalizability of a DCNN trained on EEG data from a single hospital (Hospital #1). For data from Hospital #1, the DCNN achieved a balanced accuracy (bACC) of 0.927 in classifying individuals as healthy (n = 69) or as having AD, DLB, or iNPH (n = 188). The model demonstrated robustness across institutions, maintaining bACCs of 0.805 for data from Hospital #2 (n = 73) and 0.920 at Hospital #3 (n = 139). Additionally, the model could differentiate AD, DLB, and iNPH cases with bACCs of 0.572 for data from Hospital #1 (n = 188), 0.619 for Hospital #2 (n = 70), and 0.508 for Hospital #3 (n = 139). Notably, it also identified MCI pathologies with a bACC of 0.715 for Hospital #1 (n = 83), despite being trained on overt dementia cases instead of MCI cases. These outcomes confirm the DCNN's adaptability and scalability, representing a significant stride toward its clinical application. Additionally, our findings suggest a potential for identifying shared EEG signatures between MCI and dementia, contributing to the field's understanding of their common pathophysiological mechanisms.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Aprendizado Profundo , Doença por Corpos de Lewy , Humanos , Idoso , Doença por Corpos de Lewy/diagnóstico , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Eletroencefalografia
9.
Psychogeriatrics ; 24(2): 281-294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38152057

RESUMO

BACKGROUND: We aimed to validate the Clinical Dementia Rating (CDR®) dementia staging instrument plus the National Alzheimer's Coordinating Centre Behaviour and Language Domains (CDR® plus NACC FTLD) for use in clinical settings in Japan and in the Japanese language. METHODS: This prospective observational study enrolled 29 patients with frontotemporal dementia (FTD) and 21 patients with Alzheimer's disease (AD) dementia from the Departments of Psychiatry at Osaka University Hospital and Asakayama General Hospital and the Brain Function Centre at Nippon Life Hospital. CDR® plus NACC FTLD, CDR®, Mini-Mental State Examination (MMSE), Western Aphasia Battery (WAB), Neuropsychiatric Inventory-plus (NPI-plus), Stereotypy Rating Inventory (SRI), and frontal behavioural symptom scores obtained from items of NPI-plus and SRI, were conducted to assess inter- and intra-rater reliability, validity, and responsiveness. We performed receiver operating characteristic (ROC) curve analysis to evaluate the discriminating power of the Behaviour/Comportment/Personality (BEHAV) and Language (LANG) domains of the CDR® plus NACC FTLD and the MEMORY domain of the CDR® in patients AD dementia and FTD. RESULTS: The CDR® plus NACC FTLD showed good inter- and intra-rater reliabilities. In patients with FTD, the BEHAV domain of the CDR® plus NACC FTLD was significantly correlated with all clinical measures except for the SRI total score, while the LANG domain of the CDR® plus NACC FTLD was significantly correlated with the MMSE and the WAB-Aphasia quotient. In addition, the CDR® plus NACC FTLD sum of boxes significantly changed after 6 months and after 1 year. ROC curve analysis showed that the BEHAV and LANG domains of the CDR® plus NACC FTLD distinguished between patients with AD dementia and FTD better than the MEMORY domain of the CDR®. CONCLUSIONS: This study validated the Japanese version of the CDR® plus NACC FTLD with good reliability, validity, and responsiveness.


Assuntos
Doença de Alzheimer , Afasia , Demência Frontotemporal , Doença de Pick , Humanos , Demência Frontotemporal/diagnóstico , Doença de Alzheimer/diagnóstico , Japão , Reprodutibilidade dos Testes , Testes de Estado Mental e Demência , Idioma
10.
Chem Sci ; 14(47): 13842-13850, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38075643

RESUMO

Dynamic nuclear polarization (DNP) significantly improves the sensitivity of magnetic resonance imaging, and its most important medical application is cancer diagnosis via hyperpolarized 13C-labeled pyruvate. Unlike cryogenic DNP, triplet-DNP uses photoexcited triplet electrons under mild conditions. However, triplet-DNP of pyruvate has not been observed because of incompatibility of the hydrophobic polarizing agent with hydrophilic pyruvate. This work demonstrates that supramolecular complexation with ß-cyclodextrin can disperse 4,4'-(pentacene-6,13-diyl)dibenzoate (NaPDBA), a pentacene derivative with hydrophilic substituents, even in the presence of high sodium pyruvate concentrations. The polarization of photoexcited triplet electron spins in NaPDBA was transferred to the 13C spins of sodium pyruvate via triplet-DNP of 1H spins in water and 1H-to-13C cross-polarization. This provides an important step toward the widespread use of ultra-sensitive MRI for cancer diagnosis.

11.
Intern Med ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38104993

RESUMO

A 42-year-old man was referred to our hospital because of anemia. The patient underwent gastroscopy and colonoscopy, but no bleeding site was detected. Abdominal contrast-enhanced computed tomography (CT) showed vascular dilatation along the wall of the small intestine. Small bowel capsule endoscopy and antegrade double-balloon endoscopy (DBE) were performed, and the patient was diagnosed with a small intestinal arteriovenous malformation (AVM). The AVM was clipped using DBE. After clipping, abdominal contrast-enhanced CT and small bowel angiography revealed the disappearance of the AVM. DBE may be a viable therapeutic option, helping avoid surgery and its associated risks.

12.
Sci Adv ; 9(45): eadh9986, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37939196

RESUMO

Electrocatalytic CO2 reduction is a key aspect of artificial photosynthesis systems designed to produce fuels. Although some molecular catalysts have good performance for CO2 reduction, these compounds also suffer from poor durability and energy efficiency. The present work demonstrates the improved CO2 reduction activity exhibited by molecular catalysts in a flow cell. These catalysts were composed of a cobalt-tetrapyridino-porphyrazine complex supported on carbon black together with potassium salt and were both stable and efficient. These systems were found to promote electrocatalytic CO2 reduction with a current density of 100 mA/cm2 and generated CO over at least 1 week with a selectivity of approximately 95%. The optimal catalyst gave a turnover number of 3,800,000 and an energy conversion efficiency of more than 62% even at 200 mA/cm2.

14.
Intern Med ; 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587044

RESUMO

An intrahepatic portosystemic venous shunt (IPSVS) is a rare vascular abnormality, particularly in patients without cirrhosis. An 80-year-old woman without a history of chronic liver disease was admitted to our hospital with hepatic encephalopathy. Computed tomography revealed multiple IPSVSs with two large shunts in segment 6. As conservative therapies were insufficient for treating the symptoms and reducing ammonia levels, retrograde transcaval obliteration was performed. The two large shunts were successfully embolized using detachable coils. Consequently, hyperammonemia and hepatic encephalopathy dramatically improved, and the triphasic wave patterns of the electroencephalogram disappeared. Retrograde transcaval obliteration may be effective for refractory hepatic encephalopathy with IPSVS.

15.
Biomed Rep ; 19(3): 61, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37614988

RESUMO

Acquired hemophilia A (AHA) is a rare disease that results from factor VIII inhibitors causing abnormal coagulation, and certain cases may develop after highly invasive surgery. The present case study reports on a 68-year-old male patient who developed AHA after undergoing a subtotal stomach-preserving pancreatoduodenectomy for distal cholangiocarcinoma. The patient experienced complications after surgery, requiring reoperation on postoperative day (PD) 5 due to rupture of the Braun's enterostomy. On PD 6, angiography was performed after bleeding was detected in the jejunal limb, but hemostasis occurred spontaneously during the examination. Bleeding was observed again on PD 8 and direct surgical ligation was performed. On PD 14, bleeding recurred in the jejunal limb and angiography was performed to embolize the periphery of the second jejunal artery. During the procedure, the prothrombin time was normal, but only the activated partial thromboplastin time was prolonged. A close examination of the coagulation system revealed a decrease in factor VIII levels and the presence of factor VIII inhibitors, resulting in the diagnosis of AHA. Administration of steroids was initiated on PD 15 and, in addition to daily blood transfusions, activated prothrombin complex concentrate was administered to achieve hemostasis. The patient was discharged from the intensive care unit on PD 36 but later developed an intractable labial fistula due to suture failure at the gastrojejunostomy site. As the use of factor VIII inhibitors continued despite the administration of steroids, cyclophosphamide (CPA) pulse therapy was added at PD 58. However, CPA was ineffective and the administration of rituximab was initiated on PD 98. After 12 courses of rituximab, the patient tested negative for factor VIII inhibitors on PD 219. On PD 289, labial fistula closure was performed with continuous replacement of factor VIII and the patient was discharged on PD 342.

16.
Sci Bull (Beijing) ; 68(8): 751-752, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37024328
17.
Intern Med ; 62(22): 3341-3346, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37032085

RESUMO

Atezolizumab and bevacizumab are currently available as first-line treatments for unresectable hepatocellular carcinoma, but immune-related adverse events are a major concern. We herein report two cases of isolated adrenocorticotropic hormone (ACTH) deficiency. Both patients presented with general fatigue, appetite loss, eosinophilia, and hyponatremia after nine cycles in case 1 and three months after stopping treatment for inflammatory arthritis in case 2. Endocrinological investigations revealed unsatisfactory ACTH and cortisol responses despite the preservation of other anterior pituitary hormones, suggesting isolated ACTH deficiency. As it is rapidly improved by steroid replacement therapy, an early diagnosis and treatment make it possible to resume immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Bevacizumab/efeitos adversos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/induzido quimicamente , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/induzido quimicamente , Hormônio Adrenocorticotrópico
18.
Chemphyschem ; 24(8): e202300192, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37066767

RESUMO

The front cover artwork is provided by Takashi Kato at the University of Tokyo. The image shows three assembled structures of smectic liquid crystals that show reentrant behavior. Read the full text of the Research Article at 10.1002/cphc.202200927.

19.
Molecules ; 28(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110789

RESUMO

The understanding and control of the rheological behaviors of colloids and polymer mixtures is an important issue for scientific interests and industrial applications. Aqueous mixed suspensions of silica nanoparticles and poly(ethylene oxide) (PEO) under certain conditions are interesting systems called "shake-gels", whose states vary reversibly between sol-like and gel-like under repeated shaking and being left to stand. Previous studies have indicated that the amount of PEO dose per silica surface area (Cp) is a crucial parameter for the formation of shake-gels and the relaxation time from gel-like to sol-like states. However, the relationship between the gelation dynamics and the Cp values has not been fully investigated. To determine how the gelation dynamics are affected by the Cp, we measured the time taken for silica and PEO mixtures to gelate from the sol-like to gel-like states as a function of the Cp under different shear rates and flow types. Our results show that the gelation time decreased with increasing shear rates and depended on the Cp values. Moreover, the minimum gelation time was found around a certain Cp (=0.03 mg/m2) for the first time. The finding suggests that there is an optimum Cp value at which the bridging of silica nanoparticles using PEO is significant, and thus, the shake-gels and stable gel-like states are most likely to form.

20.
Nat Commun ; 14(1): 1056, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859419

RESUMO

Singlet fission (SF), converting a singlet excited state into a spin-correlated triplet-pair state, is an effective way to generate a spin quintet state in organic materials. Although its application to photovoltaics as an exciton multiplier has been extensively studied, the use of its unique spin degree of freedom has been largely unexplored. Here, we demonstrate that the spin polarization of the quintet multiexcitons generated by SF improves the sensitivity of magnetic resonance of water molecules through dynamic nuclear polarization (DNP). We form supramolecular assemblies of a few pentacene chromophores and use SF-born quintet spins to achieve DNP of water-glycerol, the most basic biological matrix, as evidenced by the dependence of nuclear polarization enhancement on magnetic field and microwave power. Our demonstration opens a use of SF as a polarized spin generator in bio-quantum technology.

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