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1.
Sports (Basel) ; 10(11)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36422949

RESUMEN

Chronic oxidative stress in long-distance runners adversely affects conditioning. It is important to objectively assess and monitor oxidative stress, but measuring oxidative stress can be invasive or require skill to measure. Therefore, this study aimed to verify whether skin autofluorescence (SAF), a non-invasive, rapid, and easily calculable metric for calculating advanced glycation end products (AGEs), is useful as an oxidative stress biomarker. The subjects were 50 young Japanese male long-distance runners (aged 20.2 ± 1.2 years); 35 average-sized male university students (aged 19.8 ± 1.1 years) served as controls. The interactions and relationships between SAF and plasma pentosidine and oxidative stress markers (reactive oxygen metabolite-derived compounds [d-ROMs], biological antioxidant potential [BAP], and the BAP/d-ROMs ratio) in runners were examined, and SAF in the runners and controls was compared. The results suggest that plasma pentosidine in runners is associated with oxidative stress markers and that it can assess oxidative stress. However, as SAF was not associated with oxidative stress markers, it was not validated as one. In future, clarifying the factors affecting SAF may also clarify the relationship between SAF, plasma pentosidine, and oxidative stress markers.

2.
Immunopharmacol Immunotoxicol ; 44(1): 76-86, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34844505

RESUMEN

CONTEXT: We previously reported that monoclonal mouse immunoglobulin (Ig) A, OA-4, attenuates sensitization in mice by suppressing B cell activation. OBJECTIVE: Here, it is demonstrated for the first time that mouse IgA inhibits mouse B cell activation in vitro under natural conditions (i.e. in the absence of chemical, physical, and genetic modifications of IgA and B cells). MATERIALS AND METHODS: Mouse splenocytes were stimulated with anti-B cell receptor (BCR) antibody or lipopolysaccharide (LPS) in the presence or absence of OA-4. Splenic B cell proliferation and the activation of several intracellular signaling molecules were measured. RESULTS: Anti-BCR antibody-induced proliferation was markedly inhibited by OA-4 or the commercially available mouse IgA S107, whereas LPS-induced proliferation was weakly attenuated by a high concentration of OA-4. Moreover, OA-4 markedly decreased the anti-BCR antibody-induced phosphorylation of p44/42 mitogen-activated protein kinase (ERK) and CD22 and decreased phosphorylated phospholipase (PLC) γ2 and intracellular Ca2+ levels moderately, whereas protein kinase B (Akt) phosphorylation was not affected by OA-4. The MAPK/ERK kinase-ERK and phosphoinositide 3-kinase-Akt pathways were found to play a role in the proliferation of splenocytes induced by anti-BCR antibody based on experiments with their inhibitors. In contrast to that in splenic B cells, ERK phosphorylation induced by anti-BCR antibody in A20 cells was not inhibited by OA-4. The modulatory effects of IgA were different among the cell types and signaling pathways. CONCLUSION: IgA is a potential immunoregulatory drug utilizing new mechanisms that affect splenic B cells but not A20 lymphomas.


Asunto(s)
Linfocitos B/inmunología , Inmunoglobulina A , Receptores de Antígenos de Linfocitos B , Transducción de Señal , Animales , Activación de Linfocitos , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Receptores de Antígenos de Linfocitos B/metabolismo
3.
Sci Rep ; 8(1): 63, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29323134

RESUMEN

Phase transition materials are attractive from the viewpoints of basic science as well as practical applications. For example, optical phase transition materials are used for optical recording media. If a phase transition in condensed matter could be predicted or designed prior to synthesizing, the development of phase transition materials will be accelerated. Herein we show a logical strategy for designing a phase transition accompanying a thermal hysteresis loop. Combining first-principles phonon mode calculations and statistical thermodynamic calculations considering cooperative interaction predicts a charge-transfer phase transition between the A-B and A+-B- phases. As an example, we demonstrate the charge-transfer phase transition on rubidium manganese hexacyanoferrate. The predicted phase transition temperature and the thermal hysteresis loop agree well with the experimental results. This approach will contribute to the rapid development of yet undiscovered phase transition materials.

4.
Sci Rep ; 7(1): 8088, 2017 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-28839222

RESUMEN

Recent developments in terahertz technologies provide new tools for analysis, inspection, and nondestructive sensing. If a heavy atom is encapsulated in a cage of a porous material, the atom should vibrate slowly and resonate with a low-frequency terahertz light. From this perspective, a cyanide-bridged metal framework is a suitable system because it contains many cages that can adsorb Cs ions. Herein we show the vibration mode of a Cs ion in a cage of a cyanide-bridged metal framework. First-principles phonon mode calculations and terahertz time-domain spectroscopy (THz-TDS) measurements indicate that the vibration mode of a Cs ion in a cyanide-bridged manganese-iron framework is at 1.5 THz, which is significantly apart from other lattice vibrations. Taking advantage of this feature, we develop a THz-light detection method for Cs ions, which is useful for non-contact sensing of Cs ions in dangerous environments or harmful circumstances.

5.
J Obstet Gynaecol Res ; 34(2): 189-94, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18412780

RESUMEN

AIM: Japan has a shortage of tertiary medical care facilities for maternal and fetal medicine. Establishment of efficient medical transport systems is needed for pregnant women and fetuses with severe complications. Maternal transport by helicopters is expected to shorten transportation time to advanced facilities, although its feasibility has not yet been evaluated. The aim of the present study was to investigate the status of maternal helicopter transport, and conditions of the pregnant patients and children transferred by helicopter to Kameda Medical Center (KMC). METHODS: Between August 2005 and July 2006, 26 pregnant women were transported by helicopters to KMC. RESULTS: The median net flight time was 24 min (range 15-29 min), and the median of estimation of ground transportation time was 125 min (range 90-180 min). The causes for transfers were preterm labor in eight, preterm premature rupture of the membrane in five, cervical incompetence in five, pre-eclampsia in three and other medical reasons in five. Five of the 26 patients were discharged with restored stability of pregnancy. The remaining 21 patients underwent delivery at KMC. The median gestational age was 26 weeks (range 22-33 weeks) at the time of transfer and 31 weeks (range 22-37 weeks) at delivery. Four of 26 neonates who were born at KMC died after birth due to severe premature or congenital anomaly. Seventeen of the remaining 22 neonates, including 10 twins, received treatment in the neonatal intensive care unit. All of the 22 neonates and all the mothers were discharged in good condition. No patients developed any complications requiring treatment during flights. CONCLUSION: Helicopter transfer is feasible for pregnant patients with severe complications.


Asunto(s)
Ambulancias Aéreas/normas , Urgencias Médicas , Transferencia de Pacientes/métodos , Complicaciones del Embarazo , Adulto , Femenino , Humanos , Recién Nacido , Transferencia de Pacientes/normas , Embarazo
6.
Ultrasound Med Biol ; 29(10): 1471-7, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14597344

RESUMEN

This study was an investigation of arterial contractility in response to high-intensity focused ultrasound (HIFU) and of histologic changes to the artery with various intensities of HIFU. We constructed a prototype HIFU transducer in combination with an imaging probe that provides color Doppler imaging and Doppler velocimetry. HIFU was applied through the skin to deep femoral arteries in left thighs of Sprague-Dawley rats; color images of the blood flow were used to aim the HIFU beam. Peak intensities used were 530, 1080, 2750 and 4300 W/cm2. The duration of each HIFU exposure was 5 s. HIFU was applied to five focal spots of each leg. These focal spots were aligned with a spacing of 1.0 mm so as to form a line across the artery. Blood flow occlusion was accomplished by HIFU at an intensity of 4300 W/cm2, but the flow continued with the lower intensities. Peak systolic velocities (PSVs) of blood flow as measured by Doppler velocimetry increased in the arteries to which HIFU had been applied at 1080 and 2750 W/cm2. The increase corresponded with HIFU intensity. Exposure to HIFU at 530 W/cm2 did not change the blood flow velocity. Histologic studies have demonstrated that exposure to HIFU at 2750 and 4300 W/cm2 leads to vacuolar degeneration and destruction of elastic fibers of the tunica media of the artery. Exposure at 1080 W/cm2 led to increased PSV, but did not induce histologic changes in the vessel wall. In conclusion, the response of the artery to HIFU varied with intensity. Vascular contraction without tissue degeneration occurred at low intensity; with increasing intensity, the tissue degeneration detectable in histology reduced the vascular diameter and, finally, at high intensity, the blood flow was occluded. Although these phenomena appeared to be mainly due to thermal effects, mechanical effects might have some role, particularly on vascular contraction.


Asunto(s)
Arteria Femoral/fisiopatología , Terapia por Ultrasonido/métodos , Animales , Velocidad del Flujo Sanguíneo , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/patología , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional , Transductores , Túnica Media/patología , Terapia por Ultrasonido/instrumentación , Ultrasonografía Doppler en Color , Vasoconstricción
7.
J Med Ultrason (2001) ; 29(3): 85-90, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27277881

RESUMEN

High intensity focused ultrasound (HIFU) has been used in a number of clinical studies. High intensity focused ultrasound could become the minimally invasive tumor therapy of choice if it could be used to occlude the feeding arteries of tumors by exposure from outside the body. We used high intensity focused ultrasound to insonate the femoral arteries of both thighs of 18 male and female Sprague-Dawley (SD) rats, at frequencies of 1 or 3 MHz. Duration of exposure to high intensity focused ultrasound was 5 or 10 seconds. The femoral artery that was exposed to high intensity focused ultrasound was resected immediately after or 24 hours, 48 hours, or 12 days (at 1 MHz) after insonation. Arterial blood flow occlusion was achieved at 3 MHz, but not at 1 MHz. Free-field spatial peak intensity was 800 W/cm(2) at 1 MHz and 10 kW/cm(2) at 3 MHz. Histologic examination of the resected specimen showed that changes varied with ultrasound frequency and time course after exposure to high intensity focused ultrasound. We suggest that high intensity focused ultrasound might prove useful in occluding arteries when treating tumors in the clinical setting.

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