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1.
Phys Chem Chem Phys ; 26(20): 14825-14831, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38721684

RESUMEN

Polycrystalline phosphorus-doped diamond was fabricated by the quartz-tube-type microwave plasma-assisted chemical vapor deposition method. Significantly, red phosphorus was used as a source of phosphorous, instead of PH3. Phosphorus-doped diamond electrodes with hydrogen-terminated and oxygen-terminated surfaces were investigated for the redox reactions of K3[Fe(CN)6] and [Ru(NH3)6]Cl3. The carrier concentration was estimated as 2.1-5.3 × 1018 cm-3 from electrochemical impedance measurements. Polycrystalline phosphorus-doped diamond shows great promise as chemical electrode materials.

2.
Xenotransplantation ; 29(2): e12739, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35279886

RESUMEN

BACKGROUND: Some clinical trials have shown the usefulness of stem cell therapy for diabetic foot ulcers. However, the donor supply is limited, and the process is time consuming and expensive. This study assessed the therapeutic effects of neonatal porcine bone marrow-derived mesenchymal stem cell (npBM-MSC) xenotransplantation using diabetic wound model mice. METHODS: All layers of back skin were removed from streptozotocin-induced diabetic mice. In the npBM-MSCs group, npBM-MSCs were transplanted to the wound, and syngeneic mouse bone marrow-derived mesenchymal stem cells (mBM-MSCs) were transplanted to the wound in the mBM-MSCs group. The control group comprised diabetic mice that did not receive cellular therapy. The therapeutic effects of the transplantation were evaluated according to the rate of wound closure and the promotion of neovascularization in the wound. RESULTS: The wound closure rate was significantly improved in the npBM-MSCs group compared with the control group (p < .001 at postoperative day [POD] 4 and p < .01 at POD 7) and mBM-MSCs groups (p < .05 at POD 4). Prominent promotion of both angiogenesis and lymphangiogenesis was observed in the npBM-MSCs group. Furthermore, the expression of murine Prox1 and both porcine and murine Vegfs and Tgfb1 in the wounds was enhanced until POD 4 by npBM-MSCs transplantation. The amounts of vascular endothelial growth factor (VEGF) A, VEGFC, and transforming growth factor ß1 secreted from npBM-MSCs were higher than those from mBM-MSCs (p < .05). CONCLUSION: Xenotransplantation of npBM-MSCs improved diabetic wound healing by promoting both angiogenesis and lymphangiogenesis.


Asunto(s)
Diabetes Mellitus Experimental , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Animales , Médula Ósea/metabolismo , Diabetes Mellitus Experimental/terapia , Linfangiogénesis , Ratones , Porcinos , Trasplante Heterólogo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas
3.
Xenotransplantation ; 28(4): e12693, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33960029

RESUMEN

BACKGROUND: The clinical utility of stem cell therapy for peripheral artery disease has not been fully discussed, and one obstacle is limited donor supplies. In this study, we attempted to rescue mouse ischemic hind limb by xenotransplantation of neonatal porcine bone marrow-derived mesenchymal stem cells (npBM-MSCs). METHODS: Neonatal porcine bone marrow-derived mesenchymal stem cells were transplanted to ischemic hind limbs of male C57BL/6J mice (npBM-MSCs group). Mice with syngeneic transplantation of mouse BM-MSCs (mBM-MSCs group) were also prepared for comparison. The angiogenic effects were evaluated by recovery of blood flow on laser Doppler imaging, histologic findings, and genetic and protein levels of angiogenic factors. RESULTS: Regarding laser Doppler assessments, blood flow in the hind limb was rapidly recovered in the npBM-MSCs group, compared with that in the mBM-MSCs group (P = .016). Compared with the mBM-MSCs group, the npBM-MSCs group had early and prominent lymphangiogenesis [P < .05 on both post-operative days (PODs) 3 and 7] but had similar angiogenesis. Regarding genomic assessments, xenotransplantation of npBM-MSCs enhanced the expressions of both porcine and murine Vegfc in the hind limbs by POD 3. Interestingly, the level of murine Vegfc expression was significantly higher in the npBM-MSCs group than in the mBM-MSCs group on PODs 3 and 7 (P < .001 for both). Furthermore, the secreted VEGFC protein level was higher from npBM-MSCs than from mBM-MSCs (P < .001). CONCLUSION: Xenotransplantation of npBM-MSCs contributed to the improvement of hind limb ischemia by both angiogenesis and lymphangiogenesis, especially promotion of the latter. npBM-MSCs may provide an alternative to autologous and allogeneic MSCs for stem cell therapy of critical limb ischemia.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Animales , Médula Ósea , Isquemia/terapia , Linfangiogénesis , Masculino , Ratones , Ratones Endogámicos C57BL , Porcinos , Trasplante Heterólogo
4.
J Pharmacol Sci ; 146(4): 244-248, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34116738

RESUMEN

In this study, we assessed the regulation of transient receptor potential vanilloid 4 (TRPV4) promoting lymphangio/angiogenesis to improve the ischemic hindlimb animal model, and revealed that (1) a TRPV4 agonist improved the blood flow of ischemic hindlimbs by inducing both angiogenesis and lymphangiogenesis; (2) excessive TRPV4 expression was detected on lymphatic endothelial cells (LECs) in the ischemic hindlimb; and (3) hypoxic conditions promoted Ca2+ influx into LECs via TRPV4. It is considered that the upregulation of both lymphatic and blood vessels by activating TRPV4 would be a promising therapeutic strategy for peripheral artery disease.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Miembro Posterior/irrigación sanguínea , Isquemia/genética , Isquemia/terapia , Linfangiogénesis/genética , Linfangiogénesis/fisiología , Neovascularización Fisiológica/genética , Neovascularización Fisiológica/fisiología , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/fisiología , Animales , Calcio/metabolismo , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Ratones , Terapia Molecular Dirigida , Canales Catiónicos TRPV/metabolismo , Regulación hacia Arriba/genética
5.
Electrophoresis ; 38(9-10): 1344-1352, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28261824

RESUMEN

mAbs are currently mainstream in biopharmaceuticals, and their market has been growing due to their high target specificity. Characterization of heterogeneities in mAbs is performed to secure their quality and safety by physicochemical analyses. However, they require time-consuming task, which often strain the resources of drug development in pharmaceuticals. Rapid and direct method to determine the heterogeneities should be a powerful tool for pharmaceutical analysis. Considering the advantages of electrophoresis and MS, this study addresses the combination of SDS-PAGE and intact mass analysis, which provides direct, rapid, and orthogonal determination of heterogeneities in mAb therapeutics. mAb therapeutics that migrated in SDS-PAGE were recovered from gel by treatment with SDC-containing buffer. Usage of SDC-containing buffer as extraction solvent and ethanol-based staining solution enhanced the recovery of intact IgG from SDS-PAGE gels. Recovery of mAbs reached more than 86% with 0.2% SD. The heterogeneities, especially N-glycan variants in the recovered mAb therapeutics, were clearly determined by intact mass analysis. We believe that the study is important in pharmaceuticals‧ perspective since orthogonal combination of gel electrophoresis and intact mass analysis should be pivotal role for rapid and precise characterization of mAbs.


Asunto(s)
Anticuerpos Monoclonales/química , Cromatografía Líquida de Alta Presión/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Polisacáridos/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Anticuerpos Monoclonales/análisis , Polisacáridos/análisis
6.
Kyobu Geka ; 68(3): 221-3, 2015 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-25743557

RESUMEN

A 48-year-old male visited the emergency room suffering from acute dysarthria and right hemiplegia. Brain magnetic resonance imaging (MRI) revealed multiple cerebral infarctions. Echocardiography showed a mass in the left atrium. He was diagnosed with cerebral embolism due to left atrial myxoma. Open heart surgery immediately after the attack is generally considered contraindicated because of such problems as hemorrhagic infarction or brain edema. However, relapse of embolism may make the condition worse and miss the timing of surgery. Eventually, we electively performed excision of the myxoma 20 days after the onset of cerebral infarction. The postoperative course was uneventful. This is a report about a rare case of open heart surgery shortly after the attack. The indication and the appropriate timing of open heart surgery following cerebral embolism were discussed.


Asunto(s)
Infarto Cerebral/etiología , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/cirugía , Embolia Intracraneal/etiología , Mixoma/complicaciones , Mixoma/cirugía , Enfermedad Aguda , Procedimientos Quirúrgicos Cardíacos , Infarto Cerebral/diagnóstico , Infarto Cerebral/prevención & control , Disartria/etiología , Ecocardiografía , Procedimientos Quirúrgicos Electivos , Atrios Cardíacos , Neoplasias Cardíacas/diagnóstico , Hemiplejía/etiología , Humanos , Embolia Intracraneal/diagnóstico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mixoma/diagnóstico , Recurrencia , Factores de Tiempo , Resultado del Tratamiento
7.
Sci Rep ; 10(1): 19432, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33173076

RESUMEN

Plasma-assisted polishing (PAP) as a damage-free and highly efficient polishing technique has been widely applied to difficult-to-machine wide-gap semiconductor materials such as 4H-SiC (0001) and GaN (0001). In this study, a 20-mm square large mosaic single crystal diamond (SCD) substrate synthesized by microwave plasma chemical vapor deposition (CVD) was polished by PAP. Argon-based plasma containing oxygen was used in PAP to modify the surface of quartz glass polishing plate, and a high material removal rate (MRR) of 13.3 µm/h was obtained. The flatness of SCD polished by PAP measured by an interferometer was 0.5 µm. The surface roughness measured by both scanning white light interferometer (SWLI) (84-µm square) and atomic force microscope (AFM) (5-µm square) was less than 0.5 nm Sq. The micro-Raman spectroscopy measurement results of mosaic SCD substrate processed by PAP showed that residual stress and non-diamond components on the surface after PAP processing were below the detection limit.

8.
Rapid Commun Mass Spectrom ; 23(20): 3264-8, 2009 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-19757450

RESUMEN

In this study, we present molecular depth profiling of multilayer structures composed of organic semiconductor materials such as tris(8-hydroxyquinoline)aluminum (Alq3) and 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD). Molecular ions produced from Alq3 and NPD were measured by linear-type time-of-flight (TOF) mass spectrometry under 5.5 keV Ar70) ion bombardment. The organic multilayer films were analyzed and etched with large Ar cluster ion beams, and the interfaces between the organic layers were clearly distinguished. The effect of temperature on the diffusion of these materials was also investigated by the depth profiling analysis with Ar cluster ion beams. The thermal diffusion behavior was found to depend on the specific materials, and the diffusion of Alq3 molecules was observed to start at a lower temperature than that of NPD molecules. These results prove the great potential of large gas cluster ion beams for molecular depth profiling of organic multilayer samples.

9.
Rapid Commun Mass Spectrom ; 23(11): 1601-6, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19399762

RESUMEN

We demonstrate depth profiling of polymer materials by using large argon (Ar) cluster ion beams. In general, depth profiling with secondary ion mass spectrometry (SIMS) presents serious problems in organic materials, because the primary keV atomic ion beams often damage them and the molecular ion yields decrease with increasing incident ion fluence. Recently, we have found reduced damage of organic materials during sputtering with large gas cluster ions, and reported on the unique secondary ion emission of organic materials. Secondary ions from the polymer films were measured with a linear type time-of-flight (TOF) technique; the films were also etched with large Ar cluster ion beams. The mean cluster size of the primary ion beams was Ar(700) and incident energy was 5.5 keV. Although the primary ion fluence exceeded the static SIMS limit, the molecular ion intensities from the polymer films remained constant, indicating that irradiation with large Ar cluster ion beams rarely leads to damage accumulation on the surface of the films, and this characteristic is excellently suitable for SIMS depth profiling of organic materials.

10.
Data Brief ; 19: 2442-2444, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30229117

RESUMEN

In April 2014 and 2015, field samplings were conducted in a subtropical seagrass-seaweed mixed bed in Ishigaki Island, southwest Japan in order to collect macrophytes and mobile epi-benthic invertebrates. This article describes macrophyte biomass of 16 species or groups and invertebrate abundance of 66 species or groups. This data is associated with "Phylogenetically diverse macrophyte community promotes species diversity of mobile epi-benthic invertebrates" (Nakamoto et al., 2018) [1].

11.
Eur J Cardiothorac Surg ; 54(2): 318-327, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29462268

RESUMEN

OBJECTIVES: Materials used in paediatric cardiac surgery have drawbacks of deterioration, calcification and pseudointimal proliferation resulting in haemodynamic disturbance. The aim of this study was to investigate whether these drawbacks can be overcome by in situ tissue regeneration using a newly developed synthetic hybrid fabric (SHF). METHODS: The SHF is an expandable, warp-knitted fabric composed of a combination of biodegradable [poly-l-lactic acid (PLLA)] and non-biodegradable (polyethylene terephthalate) yarns. The fabric is coated with cross-linked gelatin. Mechanical properties of the SHF were compared with those of 2 commercial products: expanded polytetrafluoroethylene sheet and glutaraldehyde-treated bovine pericardium. An oval-shaped defect created in the canine descending aorta or inferior vena cava was filled with the SHF patch. After 2 weeks and 1, 3, 6 and 12 (or 24 in the inferior vena cava) months, the patch was removed for histological examination and evaluation of the remaining PLLA. RESULTS: The SHF exhibited satisfactory tensile and suture retention strength for surgical implantation similar to or better than the 2 commercial products. Tissue regeneration was induced with multilayered smooth muscle cells and collagen fibres on both sides of the patch, along with a mature endothelial layer and tissue connections containing vasa vasorum across the patch in the aorta and inferior vena cava. Inflammatory reactions were minimal, and no calcium deposition occurred. The molecular weight of PLLA was reduced to half at 12 months after implantation. CONCLUSIONS: The SHF may solve the drawbacks of the existing products. Further studies of the expandability of the SHF patch after degradation of PLLA are warranted.


Asunto(s)
Implantes Absorbibles , Aorta/cirugía , Regeneración Tisular Dirigida/instrumentación , Regeneración Tisular Dirigida/métodos , Cardiopatías Congénitas/cirugía , Vena Cava Inferior/cirugía , Animales , Bioprótesis , Bovinos , Modelos Animales de Enfermedad , Perros , Gelatina/uso terapéutico , Ensayo de Materiales , Pericardio/trasplante , Poliésteres/uso terapéutico , Politetrafluoroetileno/uso terapéutico , Resistencia a la Tracción
12.
J Biomed Mater Res B Appl Biomater ; 80(1): 273-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16767738

RESUMEN

To examine the antiadhesive effect of an alginate solution following tendon surgery, unilateral subtotal laceration of the flexor digitorum communis tendon was created in one hind limb while the other side was left intact in 32 Japanese white rabbits. The lesion was coated with alginate solution in 16 animals and not coated in the other 16. Degree of adhesion formation was assessed histologically and biomechanically by measuring the flexion angle of the first toe when the flexor digitorum tendon was pulled with a specified force at 4 weeks postoperatively. When compared with the control group, the alginate-treated group demonstrated significantly greater toe flexion, with less scar tissue formation at the repair site. Histologically, complete tendon healing with longitudinal remodeling of collagen fibers was observed in the alginate-treated group, while a random pattern of fibers was observed in the control group. Reduction in adhesion formation using alginate solution represents a novel strategy for the management of tendon injury and repair in the clinical setting.


Asunto(s)
Alginatos/farmacología , Materiales Biocompatibles/farmacología , Cicatriz/tratamiento farmacológico , Traumatismos de los Tendones/tratamiento farmacológico , Tendones , Cicatrización de Heridas/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/farmacología , Conejos , Traumatismos de los Tendones/patología , Traumatismos de los Tendones/fisiopatología , Tendones/patología , Tendones/fisiopatología
13.
Jpn J Ophthalmol ; 51(1): 53-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17295142

RESUMEN

PURPOSE: To demonstrate the usefulness of a video-meibography system featuring our newly designed probe. METHODS: This study utilized a newly designed probe featuring an obliquely inclined, T-shaped head containing 16 windows in the portion of the probe applied for emitting infrared light. The transilluminated structure of the meibomian gland is conducted to a highly sensitive, infrared charge-coupled device video camera and recorded digitally. The utility of the new probe was compared with the intraocular illumination probe traditionally used for meibography, both being applied to the eyelids of ten healthy volunteers and ten patients with meibomian gland dysfunction. The results were then analyzed. RESULTS: The newly designed probe facilitated eyelid eversion and transilluminated the meibomian gland structure effectively. Moreover, subjects experienced no irritation and only limited invasiveness when the new probe was applied. CONCLUSIONS: Our meibography system featuring the newly designed probe provided greater ease of use, an improved visualization of the meibomian gland structure, and increased comfort for patients during the examination.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico , Enfermedades de los Párpados/diagnóstico , Glándulas Tarsales/patología , Fotograbar/instrumentación , Grabación en Video/métodos , Adulto , Femenino , Humanos , Rayos Infrarrojos , Masculino , Glándulas Tarsales/anatomía & histología , Persona de Mediana Edad
14.
J Nutr Sci Vitaminol (Tokyo) ; 52(6): 402-6, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17330502

RESUMEN

In the previous analysis of our human mineral balance studies, we demonstrated positive correlations between the balances of calcium (Ca) and magnesium (Mg) and sodium (Na) intake in the range of 3.06 and 4.06 g/d or 43.71 and 96.40 mg/kg body weight (BW)/d, but there was no correlation between Na intake and Na balance. This suggested that the balances of Ca and Mg are affected by Na intake. Therefore, in the current study, we recalculated equilibrium intakes for Ca and Mg when balances of their intakes and outputs were equal to zero within the above Na range to reduce the effects of Na intake. From 1986 to 2000, 90 volunteers (10 male, 80 female; age 18 to 28 y) took part in 9 mineral balance studies. The balance periods ranged from 8 to 12 d, with adaptation periods of 2 to 4 d. The dietary intakes of Ca and Mg ranged from 294 to 719 and 154 to 334 mg/d, or from 4.83 to 15.07 and 2.44 to 6.42 mg/kg BW/d, respectively. Intake of Ca significantly correlated with Ca balance (r2 = 0.268; p < 0.0001). When the balance was equal to zero, the mean value and upper limit of the 95% confidence interval for the regression equation between intake vs. balance were 10.072 and 10.660 mg/kg BW/d, respectively. Mg intake correlated significantly with Mg balance (r2 = 0.141, p = 0.003). When the balance was equal to zero, the mean value and upper limit of the 95% confidence interval for the regression equation between intake and balance were 4.078 and 4.287 mg/kg BW/d, respectively.


Asunto(s)
Calcio de la Dieta/administración & dosificación , Magnesio/administración & dosificación , Sodio en la Dieta/administración & dosificación , Adolescente , Adulto , Calcio/metabolismo , Calcio/orina , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía/fisiología , Heces , Femenino , Humanos , Japón , Magnesio/metabolismo , Magnesio/orina , Masculino , Potasio/administración & dosificación , Potasio/metabolismo , Potasio/orina , Sodio/metabolismo , Sodio/orina , Espectrofotometría Atómica/métodos , Sudor/metabolismo , Factores de Tiempo
15.
Trop Life Sci Res ; 27(1): 145-52, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27019687

RESUMEN

The objective of the present study was to provide reproductive biological information on the gonadal development of the short-finned eel, Anguilla bicolor bicolor, which inhabits the coastal waters of Thailand. Short-finned eels were collected from three coastal areas of Trang Province, southern Thailand, from September 2011 to December 2013. The gonads of 151 specimens were subjected to a histological analysis. The histological observations found both immature and maturing females. Based on the advanced oocytes within an entire ovarian section, the ovaries of the studied specimens were classified into three maturity phases: 1) the immature phase was defined by ovaries that showed oogonia and primary growth oocytes, 2) the developing phase was defined by ovaries that contained early vitellogenic-stage oocytes with some oogonia present along with cortical alveolar oocytes and many adipocytes, and 3) the late vitellogenic phase refers to ovaries that contained nearly entirely late-vitellogenic oocytes. The density of oocytes in juxtaposition to an adipose matrix is considered to represent the degree of gonadal development. The results of this study may be applicable in further defining the general spawning area of A. bicolor bicolor in regions of the Indian Ocean.

16.
J Nutr Sci Vitaminol (Tokyo) ; 51(4): 265-70, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16261999

RESUMEN

The content of calcium (Ca) and magnesium (Mg) in sweat during exercise is considerably higher during a relatively low intake of sodium (Na) of 100 mmol/d than with an intake of 170 mmol/d. For this reason and also because Ca and Mg have a negative balance with a Na intake of 100 mmol/d, we analyzed the relationship between Na intake and balances of Ca and Mg in data from 11 balance studies. From 1986 to 2000, 109 volunteers (23 males, 86 females) with an age range of 18 to 28 y took part in mineral balance studies. The balance periods ranged from 5 to 12 d. In a given experiment, the diet of each subject contained the same quantity of food, although this varied between experiments, and was supplied during the balance period without consideration of body weight. In the data of all the studies (n= 109), the balances of Ca and Mg did not correlate positively with Na intake. However, when the data of the highest Na study were excluded, the balances of Ca and Mg correlated positively with Na intake. The mean value for the regression equation between Na intake and Ca and Mg balances when the respective balance was equal to zero were, 63.308 mg Na/kg BW/d (Ca: n=96, r2=0.134) and 60.977 mg Na/kg BW/d (Mg: n=96, r2=0.268), respectively. These values are considerably higher than Na requirements estimated by inevitable Na loss. Low dietary Na may therefore be a risk factor for maintaining positive balances of Ca and Mg.


Asunto(s)
Calcio/metabolismo , Dieta Hiposódica/efectos adversos , Magnesio/metabolismo , Sodio en la Dieta/administración & dosificación , Adolescente , Adulto , Calcio/análisis , Dieta , Femenino , Humanos , Magnesio/análisis , Masculino , Necesidades Nutricionales , Análisis de Regresión , Factores de Riesgo
17.
J Nutr Sci Vitaminol (Tokyo) ; 51(3): 161-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16161766

RESUMEN

This study was conducted to estimate the requirements of sodium (Na) and potassium (K) in Japanese young adults. From 1986 to 2000, 109 volunteers (23 males, 86 females), ranging from 18 to 28 y old, took part in 11 mineral balance studies after written informed consent had been obtained. The duration of the study periods ranged from 5 to 12 d, with a 2-4 d adaptation period. Foodstuffs used in each study were selected from those commercially available. The Na and K content of the diet, feces, urine and sweat were measured by atomic absorption spectrophotometer. The results of a study in which Na intake was 6.87 g/d (ca. 300 mmol/d), the highest of all the studies, showed apparent positive Na balances. In contrast, another study in which Na intake was 2.21 g/d (ca. 100 mmol/d), the lowest of all the studies, showed apparent negative Na balances. These two studies seemed to differ from the other studies, as shown by regression equations calculated from either data of all the studies (n= 109) or data that did not include the two studies (n=90). The dietary intakes of Na and K ranged between 38.56-142.23 and 26.77-74.42 mg/kg body weight (BW)/d, or 2.21-6.87 and 1.83-3.61 g/d, respectively in the complete data, and 43.71-96.40 and 26.77-63.70 mg/kg BW/d, or 3.06-4.06 and 1.83-2.68 g/d, respectively in the data that did not include the two studies. The intakes of the two minerals were positively correlated. Na intake (Intake) was correlated positively with apparent absorption (AA) of Na, which was also correlated with Na urinary output (Urine). In the data that did not include the two studies, Na balance (Balance) was not correlated significantly with either Na Intake (r2=0.005) or AA of Na (r2=0.006). However, analysis of all the data showed a significant correlation between Na Balance and both Na Intake (r2=0.361) and AA of Na (r2=0.360). In the complete data, the mean value and upper and lower limits of the 95% confidence interval for the regression equation between Intake and Balance for Na, when balance was equal to zero (i.e mean, upper and lower limits), were 55.824, 60.787 and 50.862 mg/ kg BW/d, respectively. K Intake was correlated positively with AA of K, which was also correlated with both Urine K and K Balance. There was a significant correlation between K Intake and K Balance in both the complete data (r2=0.213) and the data that did not include the two studies (r2 = 0.116). In all the cases, mean, upper and lower limits for K were 39.161, 41.782 and 36.540 mg/kg BW/d, respectively. Intakes of Na and K did not correlate with their respective AA rates (%). Within the ranges of K Intake in this study, K Balance was affected markedly by K Intake itself as well as by Na Intake. However, in the case of Na, when the data of the highest and lowest Na intake studies were excluded from the analysis, Na Balance did not correlate with Na Intake, whereas the data of all the studies showed Na Balance was affected strongly by Na Intake. The data of this study allowed the estimated average requirements (EARs) for both minerals to be derived.


Asunto(s)
Necesidades Nutricionales , Potasio/análisis , Sodio/análisis , Adolescente , Adulto , Femenino , Humanos , Japón , Masculino , Estado Nutricional , Potasio/sangre , Potasio/orina , Potasio en la Dieta/administración & dosificación , Sodio/sangre , Sodio/orina , Sodio en la Dieta/administración & dosificación
18.
Appl Environ Microbiol ; 56(8): 2374-2377, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16348250

RESUMEN

Enzyme-catalyzed asymmetric reduction of ethyl 4-chloro-3-oxobutanoate in an organic solvent-water diphasic system was studied. NADPH-dependent aldehyde reductase isolated from Sporobolomyces salmonicolor AKU4429 and glucose dehydrogenase were used as catalysts for reduction of ethyl 4-chloro-3-oxobutanoate and recycling of NADPH, respectively, in this system. In an aqueous system, the substrate was unstable. Inhibition of the reaction and inactivation of the enzymes by the substrate and the product were also observed. An n-butyl acetate-water diphasic system very efficiently overcame these limitations. In a 1,600-ml-1,600-ml scale diphasic reaction, ethyl (R)-4-chloro-3-hydroxybutanoate (0.80 mol; 86% enantiomeric excess) was produced from the corresponding oxoester in a molar yield of 95.4% with an NADPH turnover of 5,500 mol/mol.

19.
Zoolog Sci ; 21(1): 79-85, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14745107

RESUMEN

We have previously shown that the testicular development of underyearling male masu salmon Oncorhynchus masou reared under a long photoperiod was accelerated by oral melatonin treatment (0.5 mg melatonin/kg body weight/day), suggesting that melatonin mediates photoperiodic signaling. In this study, we further examined the effects of a disturbance in the plasma melatonin profile on gonadal development in underyearling male masu salmon by administering a higher dose of melatonin. Fish randomly selected in June were divided into two groups. They were reared under a light:dark (LD) cycle of 16:8 (lights on 04:00-20:00 hr) and fed with pellets sprayed with melatonin or vehicle twice a day at 08:30 and at 15:30 hr (7.5 mg melatonin/kg body weight/day) until October. Fish were sampled on Day 0, 25, 60, 90 and 120. The plasma melatonin levels were high in the dark phase and low in the light phase in the control group, while they were constantly high with no significant change in the melatonin-treated group. Melatonin treatment had inhibitory effects on the gonadosomatic index and plasma testosterone levels. Pituitary salmon gonadotropin-releasing hormone content and luteinizing hormone content were significantly lower in the melatonin-treated group on Day 60 and 90, respectively. These results indicate that the plasma melatonin profile is important for mediating photoperiodic signals that regulate brain-pituitary-gonadal axis in underyearling precocious male masu salmon.


Asunto(s)
Melatonina/farmacología , Oncorhynchus/crecimiento & desarrollo , Maduración Sexual/efectos de los fármacos , Testículo/crecimiento & desarrollo , Análisis de Varianza , Animales , Hormona Liberadora de Gonadotropina/sangre , Japón , Hormona Luteinizante/sangre , Masculino , Melatonina/sangre , Fotoperiodo , Testosterona/sangre , Factores de Tiempo
20.
Zoolog Sci ; 19(8): 891-8, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12193805

RESUMEN

Circadian changes in serum concentrations of testosterone (T), 11-ketotestosterone (11KT), estradiol-17beta (E2), 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP), 17alpha-hydroxyprogesterone (OHP), cortisol (F) and progesterone (P) were investigated in the spermiated/ovulated Japanese char Salvelinus leucomaenis for over three days using newly developed time-resolved fluoroimmunoassays. Testosterone and DHP in both sex and 11KT in male showed significantly (P<0.05) higher serum levels just before/after onset of darkness (15:00 or 18:00), and the levels during night and daytime were significantly (P<0.05) lower than those of the peak levels. Serum F levels in both sex during dark phase were significantly (P<0.05) higher than those levels during daytime. A surge of serum OHP concentrations in both sexes was observed at the time of twilight (03:00). The peak time of serum T, 11KT and DHP levels were approximately 6 hours prior to those of serum F and OHP levels. Serum E2 in female and P in both sex fluctuated intensely during sampling period, and did not show remarkable changes. These results strongly suggest the existence of circadian-like diel changes in serum T, DHP, F and OHP levels in both sex and 11KT in male, and no variations in serum E2 in female and P in both sex in spermiated/ovulated Japanese char under the stage of final maturation. Furthermore, relationship between circadian rhythms of steroid hormones and spawning behaviors are discussed in the present study.


Asunto(s)
Ritmo Circadiano , Hormonas Esteroides Gonadales/sangre , Trucha/sangre , Trucha/crecimiento & desarrollo , Animales , Femenino , Hidrocortisona/sangre , Masculino , Progesterona/análogos & derivados , Progesterona/sangre , Testosterona/análogos & derivados , Testosterona/sangre , Factores de Tiempo , Trucha/fisiología
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