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1.
Angew Chem Int Ed Engl ; 59(52): 23461-23465, 2020 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-33073915

RESUMO

We demonstrate hydrogen-bonded structures of water in self-organized subnanoporous water treatment membranes obtained using synchrotron-based high-resolution soft X-ray emission spectroscopy. The ion selectivity of these water treatment membranes is usually understood by the size compatibility of nanochannels in the membrane with the Stokes radius of hydrated ions, or by electrostatic interaction between charges inside the nanochannels and such ions. However, based on a comparison between the hydrogen-bonded structures of water molecules in the nanochannels of the water treatment membrane and those surrounding the ions, we propose a definite contribution of structural consistency among the associated hydrogen-bonded water molecules to the ion selectivity. Our observation delivers a novel concept to the design of water treatment membranes where water molecules in the nanochannel can be regarded as a part of the material that controls the ion selectivity.

2.
J Org Chem ; 79(3): 1068-83, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24400983

RESUMO

4,4'-Disulfanyl-2,2',5,5'-tetrahydrobiaryl (5,5'-disulfanyl hydroquinone dimer) derivatives were readily synthesized from benzoquinone and thiols via an oxidative coupling reaction. The hydroquinone dimers showed strong fluorescence upon excitation at 330 nm, and it was observed that the presence of the sulfanyl groups at the C4 and C4' positions is important for achieving strong photoluminescence. The tetrapotassium salts of the hydroquinone dimers also showed good water solubility, but the fluorescence disappeared rapidly on dissolution in water. 2,2'- and 5,5'-protected biaryls were synthesized. The dipotassium salt of the 5,5'-dimethoxy-2,2'-dihydroxy derivative was observed to show good and stable fluorescence in water, while the dipotassium salt of the 2,2'-dimethoxy-5,5'-dihydroxy derivative showed less water solubility. Introduction of propargyl groups was demonstrated to provide a convenient method for installing amino acids derivatives. This derivatization afforded potentially useful compounds for attaching the biologically active fragment to the fluorescent unit.


Assuntos
Corantes Fluorescentes/química , Hidroquinonas/química , Hidroquinonas/síntese química , Compostos de Sulfidrila/química , Compostos de Sulfidrila/síntese química , Água/química , Estrutura Molecular , Solubilidade
3.
Front Cell Dev Biol ; 12: 1288212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434621

RESUMO

Introduction: With the aim of optimizing the balance of maintaining a safe oxygen saturation and reducing the risk of retinopathy of prematurity in human neonates with fetal growth restriction (FGR), the present study investigated the distinct effects of oxygen supplementation on the retinal neovasculature using a murine premature neonatal oxygen-induced retinopathy (OIR) model with or without fetal growth restriction. Methods: For comparison with normal birth-weight neonates, maternal low-protein diet-induced FGR neonates were subjected to fluctuating oxygen levels to generate oxygen-induced retinopathy. The retinal neovasculature was histologically evaluated, and comprehensive transcriptome analysis was conducted. Results: Compared to OIR neonates with normal birth weight, significant amelioration of the neovasculature, as indicated by decreases in the number of branch junctions, vascular distribution, maximal vascular radius and microaneurysm-like tufts, was observed in OIR mice with FGR. The results of retinal RNA-sequencing revealed downregulation of angiogenic factors that trigger pathological retinal neovascularization, such as the mitogen-activated protein kinase pathway and corresponding upstream signaling pathways in OIR mice with FGR. Conclusion: Our findings demonstrated that FGR neonates have a higher capacity for retinal oxygen stress, and the risk of OIR development is attenuated compared to that in mature neonates with normal birth weight.

4.
Geriatr Gerontol Int ; 23(4): 263-269, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36855031

RESUMO

Frailty attracts research as it represents a significant target for intervention to extend the healthy life span. An unanswered question in this field is the time point during the life-course at which an individual becomes predisposed to frailty. Here, we propose that frailty has a fetal origin and should be regarded as part of the spectrum of the developmental origins of health and disease. The developmental origins of health and disease theory originated from findings linking the fetal environment to lifestyle-related disorders such as hypertension and diabetes. Coincidentally, a recent trend in frailty research also centers on vascular dysfunction and metabolic alterations as the causality of lifestyle-related disorders such as sarcopenia and dementia. Here, we explore the relationship between fetal programming, frailty-related disorders (sarcopenia and dementia), and other age-related diseases mainly based on reports on intrauterine growth restriction. We propose a "total" life-course approach to combat frailty. With this viewpoint, not only physicians and gerontologists but also obstetricians and pediatricians should team up to overcome age-related diseases in the elderly. Geriatr Gerontol Int 2023; 23: 263-269.


Assuntos
Demência , Diabetes Mellitus , Fragilidade , Sarcopenia , Humanos , Idoso , Estilo de Vida , Idoso Fragilizado
5.
Eur J Pharmacol ; 930: 175169, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35921955

RESUMO

The pulmonary pathological findings associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) result from the release of multiple proinflammatory cytokines, which causes the subsequential damage of the lungs. The current study was undertaken to investigate the responses of mast cells to viral inoculation and their contribution to host defenses from the point of view of viral entry. Pseudovirions, in which the spike glycoprotein of SARS-CoV-2 was incorporated, triggered activation of mast cells, and a mast cell-derived chymase, MCP2, formed a complex with spike protein, which promoted protease-dependent viral entry. According to the quantification results of viral entry, 10 µM quercetin, a mast cell stabilizer, potentially potently inhibited 41.3% of viral entry, while 100 µM chymostatin, which served as a chymase inhibitor, suppressed 52.1% of viral entry, compared to non-treated cells. Study using mast cell-deficient mice showed that the absence of mast cells may influence early viral loading in the upper respiratory tract, which consequently increases the risk of viral invasion into the lower respiratory system. Furthermore, mast cell-deficient mice exhibited ongoing infection in the late phase post-viral inoculation, while clearance of virus-positive cells was observed in wild-type mice. In conclusion, mast cells act as a multifaceted immune modulator that is equipped with both protective effects and pathogenic influences on viral entry of SARS-CoV-2. The utility of mast cell stabilizers and chymase inhibitors in the treatment of SARS-CoV-2-induced acute respiratory syndrome should be optimized regarding the infection stage and the risk of cytokine storm.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Quimases , Mastócitos/metabolismo , Camundongos , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus
6.
Nihon Hinyokika Gakkai Zasshi ; 93(5): 627-32, 2002 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-12174639

RESUMO

PURPOSE: We evaluated both efficacy and feasibility of laparoscopy-assisted live donor nephrectomy. MATERIALS AND METHODS: Since September 2000, 11 living kidney donors (2 males and 9 females) underwent laparoscopy-assisted live donor nephrectomy. All of sides were left. Gasless surgery was performed with a 7 cm pararectal upper abdominal incision and three trocars via a retroperitoneal approach. After creating the working space using balloon dissection technique, the abdominal wall was lifted using a metal retractor attached to the margin of the abdominal incision. Additionally, a metal plate, which was attached to the abdominal wall inside, was raised. The surgeon dissected left kidney from the skin incision under both direct vision and magnificated view on the monitor. RESULTS: The operating time, estimated blood loss and warm ischemic time were a mean of 209 minutes, 219 g, and 4.2 minutes, respectively. The mean times for the return to a normal diet and unassisted ambulation were 1.3 and 1.8 days, respectively. One case required blood transfusion due to subcutaneous hematoma at trocar entry site on the second day after surgery, in the remaining 10 cases there were no complications. All of donated kidneys achieved immediate function after engraftment. CONCLUSIONS: Gasless laparoscopy-assisted donor nephrectomy is recommended and advantageous for healthy kidney donors as a minimally invasive method.


Assuntos
Laparoscopia/métodos , Doadores Vivos , Nefrectomia/métodos , Coleta de Tecidos e Órgãos/métodos , Adulto , Idoso , Feminino , Humanos , Transplante de Rim , Masculino , Pessoa de Meia-Idade
7.
Nihon Hinyokika Gakkai Zasshi ; 93(6): 710-4, 2002 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-12385097

RESUMO

A 38-year-old man who had been followed with diagnosis of dilated cardiomyopathy and retinal angioma was referred to our hospital because of incidentally detected bilateral adrenal masses. Although he was normotensive, levels of catecholamine in urine were elevated and I131-MIBG scintigraphy showed accumulation in bilateral adrenal glands. Screening of central nervous system by MRI revealed cerebellar hemangioblastoma. Right adrenalectomy and left partial adrenalectomy were performed, both of which tumors pathologically diagnosed as pheochromocytoma, followed by resection of the cerebellar hemangioblastoma. Five months later, abdominal CT revealed a left renal tumor and underwent left partial nephrectomy, being diagnosed as renal cell carcinoma. A right renal tumor was detected on follow up CT at 1 year after the partial nephrectomy. Since cardiac function was deteriorated, we have followed with careful observation. This is the second documented case of bilateral renal cell carcinomas and bilateral pheochromocytomas with VHL in Japan.


Assuntos
Neoplasias das Glândulas Suprarrenais/etiologia , Carcinoma de Células Renais/etiologia , Neoplasias Renais/etiologia , Neoplasias Primárias Múltiplas/etiologia , Feocromocitoma/etiologia , Doença de von Hippel-Lindau/complicações , Adulto , Humanos , Masculino
8.
J Cardiol ; 56(3): 287-90, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20729038

RESUMO

In western countries, the use of a balloon-expandable covered stent is recommended for the treatment of native coarctation of the aorta (CoA) in adult patients because endovascular bare stents cannot completely prevent complications such as aneurysms or aortic rupture. However, such a product that is appropriate and officially approved is not available in Japan. We developed and used a handmade balloon-expandable covered stent in a 32-year-old patient with native CoA and achieved a good outcome. A Palmaz-Schatz stent (XL 10-series 4010; Johnson & Johnson, Warren, NJ, USA) was covered with an Ube woven-graft (WST series; 18 mm across; Ube Junken Medical, Tokyo, Japan). Because the stent shortens when dilated, one end of the graft was firmly sutured to one end of the stent, whereas the other end of the graft was stitched loosely to the other end of the stent so that it could slide along the struts of the stent to accommodate foreshortening. After meticulous in vitro simulations, the covered stent was implanted with right ventricular overdrive pacing. No complications were observed, and the pressure gradient disappeared. These results indicate that angioplasty using a balloon-expandable covered stent is highly safe and effective for correcting native CoA in adult patients and hopefully in children.


Assuntos
Angioplastia com Balão/métodos , Materiais Revestidos Biocompatíveis , Desenho de Prótese , Stents , Adulto , Angioplastia com Balão/instrumentação , Coartação Aórtica/terapia , Implante de Prótese Vascular/métodos , Feminino , Humanos , Japão , Resultado do Tratamento
9.
Int J Urol ; 13(1): 80-3, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16448439

RESUMO

We previously reported a case of bilateral ureteral stenosis accompanied by systemic lupus erythematosus, which was successfully managed by total ureteral reconstruction using a segment of the ileum. Herein, we describe an unusual complication in the same patient, which we experienced 5 years after the ileal-ureteral substitution. Left-sided back pain repeated together with transient obstruction of the ileal ureter interposed between the right and left renal pelvis. Consequently, exploratory laparotomy revealed that left colic vessels oppressed and caused obstruction, and the obstructed ileal ureter was released by reconstitution of these vessels instead of re-anastomosis of the ileal ureter. Left hydronephrosis and related back pain disappeared postoperatively. The number of patients with an indication of ileal-ureteral substitution is increasing for various disorders, and thus, the present report gives additional suggestions for the follow up of patients with ileal ureter.


Assuntos
Íleo/transplante , Lúpus Eritematoso Sistêmico/complicações , Artérias Mesentéricas , Ureter/cirurgia , Obstrução Ureteral/etiologia , Adolescente , Feminino , Seguimentos , Humanos , Íleo/irrigação sanguínea , Laparotomia , Recidiva , Reoperação , Fatores de Tempo , Tomografia Computadorizada por Raios X , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/cirurgia , Urografia
10.
Int J Urol ; 13(5): 606-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16771733

RESUMO

We report a rare case of primitive neuroectodermal tumor arising from adrenal gland in adulthood, diagnosed preoperatively as having non-functional adrenocortical adenoma. Laparoscopic adrenalectomy was performed. Immunohistological examination revealed the definite diagnosis as primitive neuroectodermal tumor of the adrenal gland. Although primitive neuroectodermal tumor is a highly malignant neoplasm, there is no evidence of local recurrence and distant metastasis 16 months after surgery.


Assuntos
Neoplasias das Glândulas Suprarrenais/patologia , Tumores Neuroectodérmicos Primitivos/patologia , Antígeno 12E7 , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/cirurgia , Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagem , Tumores Neuroectodérmicos Primitivos/metabolismo , Tumores Neuroectodérmicos Primitivos/cirurgia , Radiografia , Tomógrafos Computadorizados
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