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1.
Chaos ; 34(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38386906

RESUMO

In humans, ventricular folds are located superiorly to the vocal folds. Under special circumstances such as voice pathology or singing, they vibrate together with the vocal folds to contribute to the production of voice. In the present study, experimental data measured from physical models of the vocal and ventricular folds were analyzed in the light of nonlinear dynamics. The physical models provide a useful experimental framework to study the biomechanics of human vocalizations. Of particular interest in this experiment are co-oscillations of the vocal and ventricular folds, occasionally accompanied by irregular dynamics. We show that such a system can be regarded as two coupled oscillators, which give rise to various cooperative behaviors such as synchronized oscillations with a 1:1 or 1:2 frequency ratio and desynchronized oscillations with torus or chaos. The insight gained from the view of nonlinear dynamics should be of significant use for the diagnosis of voice pathologies, such as ventricular fold dysphonia.


Assuntos
Prega Vocal , Voz , Humanos , Dinâmica não Linear , Fenômenos Biomecânicos
2.
J Am Chem Soc ; 146(3): 2089-2101, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38163763

RESUMO

The self-assembled state of molecules plays a pivotal role in determining how inherent molecular properties transform and give rise to supramolecular functionalities and has long attracted attention. However, understanding the influence of morphologies spanning the nano- to mesoscopic scales of supramolecular assemblies derived from identical intermolecular interactions has been notoriously challenging due to dynamic structural change and monomer exchange of assemblies in solution. In this study, we demonstrate that curved one-dimensional molecular assemblies (supramolecular polymers) of lengths of around 70-200 nm, originating from the same luminescent molecule, exhibit distinct photoluminescent properties when they form closed circular structures (toroids) versus when they possess chain termini in solution (random coils). By exploiting the difference in kinetic stability between the toroids and random coils, we developed a dialysis protocol to selectively purify the former. It was revealed that these terminus-free closed structures manifest higher energy and more efficient luminescence compared with their mixed state with random coils. Time-resolved fluorescence measurements unveiled that random coils, due to their dynamic structural fluctuation in solution, generate local defects throughout the main chain, leading to luminescence from lower energy levels. In mixtures of the two assemblies, luminescence was exclusively observed from such a lower energy level of random coils, a result attributed to energy transfer between the assemblies. This work emphasizes that for identical supramolecular assemblies, only averaged properties have traditionally been considered, but their structures at the nano- to mesoscopic scale are important especially if they have a certain degree of shape persistency even in solution.

3.
Invest New Drugs ; 42(1): 44-52, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38055127

RESUMO

Dexamethasone is one of the key antiemetic agents and is widely used even now. However, dexamethasone has been associated with several adverse reactions even after short-term administration. Therefore, developing a steroid-free antiemetic regimen is an important issue to consider. Thus, the purpose of this study was to investigate the efficacy and safety of palonosetron, aprepitant, and olanzapine in a multi-institutional phase II study. Chemotherapy-naive patients scheduled to receive cisplatin were enrolled and evaluated for the occurrence of chemotherapy-induced nausea and vomiting during 120 h after chemotherapy. The primary endpoint of the study was total control (TC) in the overall phase. The key secondary endpoint was complete response (CR), which was assessed in the acute, delayed, and overall phase, respectively. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Events. Eighty-five patients were enrolled from 8 centers in Japan, of which 83 were evaluable for analyses. The percentage of patients who achieved TC during the overall phase was 31.3%. CR was achieved in 61.4%, 84.3%, and 65.1% of patients during the overall, acute, and delayed phases, respectively. The most frequently reported adverse event was anorexia. The primary endpoint was below the threshold and we could not find benefit in the dexamethasone-free regimen, but CR during the overall phase was similar to that of the conventional three-drug regimen. This antiemetic regimen without dexamethasone might be an option for patients for whom corticosteroids should not be an active application.


Assuntos
Antieméticos , Humanos , Antieméticos/efeitos adversos , Aprepitanto/efeitos adversos , Cisplatino/efeitos adversos , Dexametasona/efeitos adversos , Olanzapina/efeitos adversos , Palonossetrom/efeitos adversos , Resposta Patológica Completa
4.
DEN Open ; 4(1): e318, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38089923

RESUMO

A 77-year-old male patient underwent esophagogastroduodenoscopy at his family doctor, and an easily hemorrhagic depressed lesion was noted near the anterior wall of the gastric antrum. A biopsy revealed moderately differentiated tubular adenocarcinoma > poorly differentiated adenocarcinoma, and the patient was referred to our department for further examination. A 15-mm 0-IIc lesion is seen near the anterior wall of the gastric antrum and narrow band imaging magnifying endoscopy revealed obscured glandular duct structures and corkscrew pattern vascular structures. We diagnosed the patient with early-stage gastric cancer [L, Ant, 15mm, cType0-IIc, cT1(M-SM1), cN0, cM0, cStage IA] after an esopahogastroduodenoscopy examination at our hospital, and endoscopic submucosal dissection was performed. Histopathological images with hematoxylin and eosin staining showed tumor cells with pale cytoplasm and the immunostaining for alpha-fetoprotein, sal-like protein 4, and Glypican3 was positive. The patient was pathologically diagnosed with gastric adenocarcinoma with enteroblastic differentiation, pT1b1 (SM, 0.4 mm), type 0-IIc, 15 mm, UL (-), Ly0, and V0. Gastric adenocarcinoma with enteroblastic differentiation is one of the representative histological types of alpah-fetoprotein-producing gastric cancer. Alpha-fetoprotein-producing gastric cancer is infrequent, accounting for at least 3% of all gastric cancers, and is generally highly malignant. Most cases are already advanced upon diagnosis, and finding them in the early stage is rare. Therefore, pathological findings that may indicate the gastric adenocarcinoma with enteroblastic differentiation should be noted even in early gastric cancer.

5.
JASA Express Lett ; 2(11): 111201, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36456367

RESUMO

The vocal membrane, i.e., an extended part of the vocal fold, is observed in a wide range of species including bats and primates. A theoretical study [Mergell, Fitch, and Herzel (1999). J. Acoust. Soc. Am. 105(3), 2020-2028] predicted that the vocal membranes can make the animal vocalizations more efficient by lowering the phonation threshold pressure. To examine this prediction, a synthetic model of the vocal membrane was developed, and its oscillation properties were examined. The experiments revealed that the phonation threshold pressure was lower in the vocal membrane model compared to that in a model with no vocal membrane. Chaotic oscillations were observed as well.


Assuntos
Quirópteros , Fonação , Animais , Prega Vocal , Membranas , Equipamentos Médicos Duráveis , Exame Físico
6.
BMC Surg ; 22(1): 224, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690750

RESUMO

BACKGROUND: Early cholecystectomy is recommended for patients with acute cholecystitis. However, emergency surgery may not be indicated due to complications and disease severity. Patients requiring drainage are usually treated with percutaneous transhepatic gallbladder drainage (PTGBD), whereas patients with biliary duct stones undergo endoscopic stones removal followed by endoscopic gallbladder drainage (EGBD). Herein, we investigated the efficacy of EGBD in patients with acute cholecystitis. METHODS: Overall, 101 patients receiving laparoscopic cholecystectomy between September 2019 and September 2020 in our department were retrospectively analyzed. RESULTS: The patients (n = 101) were divided into three groups: control group that did not undergo drainage (n = 68), a group that underwent EGBD (n = 7), and a group that underwent PTGBD (n = 26). Median surgery time was 107, 166, and 143 min, respectively. Control group had a significantly shorter surgery time, whereas it did not significantly differ between EGBD and PTGBD groups. The median amount of bleeding was 5 g, 7 g, and 7.5 g, respectively, and control group had significantly less bleeding than the drainage group. We further divided patients into the following subgroups: patients requiring a 5 mm clip to ligate the cystic duct, patients requiring a 10 mm clip due to the thickness of the cystic duct, patients requiring an automatic suturing device, and patients undergoing subtotal cholecystectomy due to impossible cystic duct ligation. There was no significant difference between EGBD and PTGBD regarding the clip used or the need for an automatic suturing device and subtotal cholecystectomy. CONCLUSIONS: There was no significant difference between EGBD and PTGBD groups regarding surgery time or bleeding amount when surgery was performed after gallbladder drainage for acute cholecystitis. Therefore, EGBD was considered a useful preoperative drainage method requiring no drainage bag.


Assuntos
Colecistectomia Laparoscópica , Colecistite Aguda , Colecistite Aguda/cirurgia , Drenagem/métodos , Vesícula Biliar/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
7.
Biosci Biotechnol Biochem ; 86(6): 775-779, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35416247

RESUMO

Tschimganine inhibits growth and extends the chronological lifespan in Schizosaccharomyces pombe. We synthesized a Tschimganine analog, Mochimganine, which extends the lifespan similar to Tschimganine but exhibits a significantly weaker growth inhibition effect. Based on the comparative analysis of these compounds, we propose that Tschimganine has at least 2 targets: one extends the lifespan and the other inhibits growth.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Regulação Fúngica da Expressão Gênica , Longevidade , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética
8.
J Voice ; 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34903395

RESUMO

The ventricular folds, located superiorly to the vocal folds, do not usually vibrate during normal phonations. It has been shown, however, that they do vibrate together with the vocal folds under special circumstances such as voice pathology and singing voice. Towards understanding the effect of the ventricular fold oscillations on the vocal fold oscillations, the present study developed a synthetic model that takes into account anatomical features of the human ventricular folds. The synthetic model is made of flexible silicone compounds with material properties comparable to those of human ventricular fold tissues. In our experiment, an air-flow was injected into the vocal and ventricular fold models. As the distance between the left and right ventricular folds was reduced, the ventricular folds started to co-vibrate with the vocal folds. Depending upon the distance, various oscillation patterns of the vocal-ventricular folds were observed, e.g., synchronized dynamics with 1:1 or 1:2 frequency ratio and desynchronized chaotic dynamics. The observed chaotic dynamics might be related to voice pathology induced by the ventricular phonation. A computational model was further presented to elucidate the experimental findings.

9.
J Acoust Soc Am ; 149(1): 271, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514158

RESUMO

Ventricular folds are located in the supraglottal region above the vocal folds. Although the ventricular folds do not vibrate under normal vocalizations, they vibrate under certain conditions, e.g., throat singing or ventricular fold dysphonia. In throat singing, the ventricular folds vibrate at the same frequency as (or at integer ratios of) the vocal fold vibration frequency. In ventricular fold dysphonia, on the other hand, the ventricular folds interfere with the vocal folds, giving rise to a hoarse voice. In the present study, the synthetic larynx model was utilized to examine the vocal-ventricular fold oscillations. Our experiments revealed that the vocal and ventricular folds can co-oscillate at the same frequency with an out-of-phase relation. Compared to the control condition, under which no ventricular folds exist, the phonation threshold pressure was increased in the presence of the ventricular folds. Acoustic analysis indicated that jitter was reduced and vocal efficiency was increased by the ventricular folds. Distance between the vocal and ventricular folds did not alter these oscillation properties. A computational model was further simulated to elucidate the mechanism underlying the observed vocal-ventricular fold oscillations. It has been suggested that out-of-phase oscillations of the vocal and ventricular folds are important for sustaining periodic laryngeal vibrations.


Assuntos
Laringe , Prega Vocal , Voz , Acústica , Humanos , Fonação , Vibração
10.
Gan To Kagaku Ryoho ; 48(13): 1640-1642, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35046282

RESUMO

The patient is a 40-year-old male. He was referred to our department because, after a thorough examination, he was diagnosed with rectal cancer. Preoperative imaging showed a tumor in the rectum at the level of the seminal vesicles, and left lateral invasion was suspected. In addition, lymph node metastases in the left lateral area were suspected. We performed a robot-assisted low anterior resection plus bilateral lateral dissection plus covering ileostomy for this patient after neoadjuvant chemotherapy. The operation time was 495 minutes, and the blood loss was 50 g. The histopathological diagnosis was pT3, N3(#263), M0, pStage Ⅲc, PM0, DM0, RM0, R0, Cur A. In Japan, robotic-assisted surgery for rectal cancer has been covered by insurance since April 2018, and in our department, robotic surgery is the first option for any stage or type of surgery for rectal cancer. We believe that the greatest advantages of robotic surgery for rectal cancer are in lateral dissection, ie, the better understanding of how blood vessels and nerves travel around the internal iliac vessels and the associated anatomy of pelvic organs that comes from reliable lateral dissection. We have experienced a case of safe robotic-assisted radical resection of laterally invasive rectal cancer, which is considered to be relatively difficult, and we hereby report the usefulness of the robotic-assisted modality.


Assuntos
Laparoscopia , Protectomia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Adulto , Humanos , Excisão de Linfonodo , Masculino , Terapia Neoadjuvante , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgia , Reto , Resultado do Tratamento
11.
Gan To Kagaku Ryoho ; 48(13): 1706-1708, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35046304

RESUMO

The patient was a 57-year-old male. He was diagnosed with locally advanced rectal cancer infiltrating the left levator ani muscle. Chemotherapy(S-1 plus L-OHP plus bevacizumab regimen)was started for the purpose of obtaining a negative circumferential radial margin. After the second course, he presented with perforation of the sigmoid colon for which an emergency operation was performed. The perforation was located 5 centimeters above the tumor in the sigmoid colon. We performed partial resection of the sigmoid colon to repair the perforation and create a sigmoid colostomy. CT, after the initial S-1 plus L-OHP plus bevacizumab chemotherapy regimen, revealed tumor shrinkage. Following 2 more courses of chemotherapy( S-1 plus L-OHP regimen), we performed transanal total mesenteric excision(taTME)as curative surgery. R0 resection was achieved. The combined transanal and laparoscopic approach was highly effective for a patient with pan-peritonitis.


Assuntos
Laparoscopia , Protectomia , Neoplasias Retais , Colostomia , Humanos , Masculino , Mesentério , Pessoa de Meia-Idade , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgia , Reto
12.
Int J Mol Sci ; 19(4)2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29690614

RESUMO

T cell-deficient mice such as nude mice are often used to generate tumor xenograft for the development of anticancer agents. However, the functionality of the other immune cells including macrophages, dendritic cells (DCs), and myeloid-derived suppressor cells (MDSCs) in the xenograft are largely unknown. Macrophages and dendritic cells (DCs) acquire functionally distinct properties in response to various environmental stimuli; the interaction of these cells with MDSCs in tumor microenvironments regulates cancer progression. Nude mice are less likely to reject human cancer cells because of major histocompatibility complex (MHC) mismatches. The tumor microenvironment in a xenograft, comprising human and mouse cells, exhibits more complex bidirectional signaling and function than that of allograft. Here, we evaluated the differences of myeloid cells between them. Plasma interferon-γ and interleukin-18 concentrations in the xenograft tumor model after lipopolysaccharide (LPS) administration were significantly higher than those in the allograft tumor model. MHC class I, II, and CD80 expression levels were increased in CD11b⁺ and MDSC populations after LPS administration in the spleen of a xenograft tumor model but not in that of an allograft tumor model. Additionally, the number of CD80- and mannose receptor C type 1 (MRC1)-expressing cells was decreased upon LPS administration in the tumor of the xenograft tumor. These results suggest that functions of macrophages and DCs are sustained in the xenograft, whereas their functions in response to LPS were suppressed in the allograft. The findings will encourage the consideration of the effects of myeloid cells in the xenograft for drug development.


Assuntos
Citocinas/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Aloenxertos , Animais , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Células HT29 , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Nucleic Acids Res ; 42(16): 10605-17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25143533

RESUMO

LINEs mobilize their own copies via retrotransposition. LINEs can be divided into two types. One is a stringent type, which constitutes a majority of LINEs. The other is a relaxed type. To elucidate the molecular mechanism of retrotransposition, we used here two different zebrafish LINEs belonging to the stringent type. By using retrotransposition assays, we demonstrated that proteins (ORF2) encoded by an individual LINE recognize the cognate 3' tail sequence of the LINE RNA strictly. By conducting in vitro binding assays with a variety of ORF2 proteins, we demonstrated that the region between the endonuclease and reverse transcriptase domains in ORF2 is the site at which the proteins bind the stem-loop structure of the 3' tail RNA, showing that the strict recognition of the stem-loop structure by the cognate ORF2 protein is an important step in retrotransposition. This recognition can be bipartite, involving the general recognition of the stem by cTBR (conserved tail-binding region) of ORF2 and the specific recognition of the loop by vTBR (variable tail-binding region). This is the first report that clearly characterized the RNA-binding region in ORF2, providing the generality for the recognition mechanism of the RNA tail by the ORF2 protein encoded by LINEs.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Sítios de Ligação , Células HeLa , Humanos , Conformação de Ácido Nucleico , Ligação Proteica , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética
14.
Plant J ; 68(2): 262-72, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21699590

RESUMO

Of the two tRNA(Cys) (GCA) genes, trnC1-GCA and trnC2-GCA, previously identified in mitochondrial genome of sugar beet, the former is a native gene and probably a pseudo-copy, whereas the latter, of unknown origin, is transcribed into a tRNA [tRNA(Cys2) (GCA)]. In this study, the trnC2-GCA sequence was mined from various public databases. To evaluate whether or not the trnC2-GCA sequence is located in the mitochondrial genome, the relative copy number of its sequence to nuclear gene was assessed in a number of angiosperm species, using a quantitative real-time PCR assay. The trnC2-GCA sequence was found to exist sporadically in the mitochondrial genomes of a wide range of angiosperms. The mitochondrial tRNA(Cys2) (GCA) species from sugar beet (Beta vulgaris), spinach (Spinacea oleracea) and cucumber (Cucumis sativus) were found to be aminoacylated, indicating that they may participate in translation. We also identified a sugar beet nuclear gene that encodes cysteinyl-tRNA synthetase, which is dual-targeted to mitochondria and plastids, and may aminoacylate tRNA(Cys2) (GCA). What is of particular interest is that trnC1-GCA and trnC2-GCA co-exist in the mitochondrial genomes of eight diverse angiosperms, including spinach, and that the spinach tRNA(Cys1) (GCA) is also aminoacylated. Taken together, our observations lead us to surmise that trnC2-GCA may have been horizontally transferred to a common ancestor of eudicots, followed by co-existence and dual expression of trnC1-GCA and trnC2-GCA in mitochondria with occasional loss or inactivation of either trnC-GCA gene during evolution.


Assuntos
Aminoacil-tRNA Sintetases/genética , Aminoacilação/genética , Beta vulgaris/genética , Genoma Mitocondrial/genética , Magnoliopsida/genética , RNA de Transferência de Cisteína/metabolismo , Aminoacil-tRNA Sintetases/metabolismo , Beta vulgaris/enzimologia , Beta vulgaris/metabolismo , Evolução Biológica , DNA Complementar/genética , DNA Mitocondrial/genética , DNA de Plantas/genética , Bases de Dados de Ácidos Nucleicos , Dosagem de Genes , Transferência Genética Horizontal , Magnoliopsida/enzimologia , Magnoliopsida/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Conformação de Ácido Nucleico , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA de Plantas/genética , RNA de Transferência de Cisteína/genética , Análise de Sequência de DNA
15.
Science ; 318(5856): 1591-4, 2007 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-18063790

RESUMO

The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection.

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