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1.
J Environ Manage ; 169: 202-9, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26760443

RESUMEN

Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes.


Asunto(s)
Agricultura/métodos , Ambiente , Suelo , Modelos Teóricos , Lluvia , República de Corea , Estaciones del Año
2.
Front Plant Sci ; 15: 1321950, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38292912

RESUMEN

Introduction: Invasive species have been identified as a major threat to native biodiversity and ecosystem functioning worldwide due to their superiority in spread and growth. Such superiority is explained by the invasional meltdown phenomena, which suggests that invasive species facilitate the establishment of more invasive species rather than native species by modifying the plant-soil feedback (PSF). Methods: We conducted a two-phase plant-soil feedback experiment using the native Prosopis cineraria and the invasive Prosopis juliflora in Oman. Firstly, we conditioned the soil by planting seedlings of native species, invasive species, native and invasive species "mixed", and unconditioned soil served as a control. Secondly, we tested the feedback of these four conditioned soil on the two species separately by measuring the productivity (total biomass) and the performance in the form of plant functional traits (plant height, specific leaf area (SLA), leaf nitrogen content (Nmass), leaf carbon content (Cmass) and specific root length (SRL) of native and invasive species as well as the nutrient availability in soil (soil organic carbon (SOC) and soil total nitrogen (STN)). Results and discussion: We found that the native species produced more biomass, best performance, and higher SOC and STN when grown in soil conditioned by native species, additionally, it gave lower biomass, reduced performance, and lower SOC and STN when grown in the soil conditioned by invasive and mixed species. These results suggest negative PSF for native species and positive PSF for invasive species in the soil conditioned by invasive species, which can be considered as red flag concerning the restoration of P. cineraria as an important native species in Oman, as such positive PSF of the invasive species P. juliflora will inhibit the regeneration of P. cineraria.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38771456

RESUMEN

This study evaluated the effects of Technospore® (Bacillus coagulans) supplementation on intestinal health, immune response, and Oreochromis niloticus (Nile tilapia) growth performance. The experiment divided fish into four groups: a control group fed an unsupplemented diet and three experimental groups receiving diets supplemented with 0.2 g/kg, 0.4 g/kg, and 0.8 g/kg of Technospore®, respectively. Results indicated that Technospore® supplementation significantly enhanced growth rates and feed efficiency in all treated groups, with the most pronounced improvements observed in the group receiving 0.4 g/kg. Furthermore, the study revealed that B. coagulans supplementation markedly boosted serum immune responses, as evidenced by increased phagocytic activity, phagocytic index, and lysozyme levels, following a challenge with Aeromonas hydrophila. Histological analysis showed improved gut morphology, while gene expression analysis indicated upregulation of immune-related genes, including liver IGF-1, GHR, HSP70, IL-1ß, and TNF-α, as well as spleen TNF-α and IL-1ß and intestinal C-lysozyme and TNF-α, both before and after the bacterial challenge. These findings suggest that dietary inclusion of Technospore® can significantly improve gut health and immune responses in tilapia, potentially serving as an effective prophylactic alternative to antibiotics in aquaculture.

4.
Int J Oral Maxillofac Surg ; 52(5): 515-523, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36123273

RESUMEN

The aim of this study was to clarify the correlation between imaging findings obtained using intraoral ultrasonography (US) and pathological findings of tongue cancers, and to examine the predictive value of intraoral US findings with respect to occult nodal metastasis. This was a retrospective study based on the medical records of 123 patients with T1-2N0 tongue cancer. The depth of invasion (DOI) on intraoral US was positively correlated with the pathological invasion depth (PID) (ρ = 0.7080, P < 0.0001). Receiver operating characteristic analyses revealed an optimal DOI cut-off value of 4.1 mm and optimal PID cut-off value of 3.9 mm to detect nodal metastasis. Regarding the margin shape of the primary tumour on intraoral US, the incidence of nodal metastasis was significantly higher for the permeated type than for the pressure type (P < 0.001) and wedge-shaped type (P = 0.002). Furthermore, tumours with peritumoural vascularity assessed by power Doppler US had a significantly higher incidence of nodal metastasis than tumours without (P = 0.003). The sensitivity, specificity, and accuracy of the permeated type to predict nodal metastasis was 53.6%, 95.8%, and 86.2%, respectively. These results suggest that intraoral US findings closely reflect pathological findings and could be useful to predict occult nodal metastasis in patients with early-stage tongue cancer.


Asunto(s)
Neoplasias de la Lengua , Humanos , Neoplasias de la Lengua/diagnóstico por imagen , Estudios Retrospectivos , Lengua , Angiografía , Factor de Crecimiento Transformador beta , Ultrasonografía
5.
Plants (Basel) ; 12(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37299089

RESUMEN

Heavy metal stress, including from chromium, has detrimental effects on crop growth and yields worldwide. Plant growth-promoting rhizobacteria (PGPR) have demonstrated great efficiency in mitigating these adverse effects. The present study investigated the potential of the PGPR strain Azospirillum brasilense EMCC1454 as a useful bio-inoculant for boosting the growth, performance and chromium stress tolerance of chickpea (Cicer arietinum L.) plants exposed to varying levels of chromium stress (0, 130 and 260 µM K2Cr2O7). The results revealed that A. brasilense EMCC1454 could tolerate chromium stress up to 260 µM and exhibited various plant growth-promoting (PGP) activities, including nitrogen fixation, phosphate solubilization, and generation of siderophore, trehalose, exopolysaccharide, ACC deaminase, indole acetic acid, and hydrolytic enzymes. Chromium stress doses induced the formation of PGP substances and antioxidants in A. brasilense EMCC1454. In addition, plant growth experiments showed that chromium stress significantly inhibited the growth, minerals acquisition, leaf relative water content, biosynthesis of photosynthetic pigments, gas exchange traits, and levels of phenolics and flavonoids of chickpea plants. Contrarily, it increased the concentrations of proline, glycine betaine, soluble sugars, proteins, oxidative stress markers, and enzymatic (CAT, APX, SOD, and POD) and non-enzymatic (ascorbic acid and glutathione) antioxidants in plants. On the other hand, A. brasilense EMCC1454 application alleviated oxidative stress markers and significantly boosted the growth traits, gas exchange characteristics, nutrient acquisition, osmolyte formation, and enzymatic and non-enzymatic antioxidants in chromium-stressed plants. Moreover, this bacterial inoculation upregulated the expression of genes related to stress tolerance (CAT, SOD, APX, CHS, DREB2A, CHI, and PAL). Overall, the current study demonstrated the effectiveness of A. brasilense EMCC1454 in enhancing plant growth and mitigating chromium toxicity impacts on chickpea plants grown under chromium stress circumstances by modulating the antioxidant machinery, photosynthesis, osmolyte production, and stress-related gene expression.

6.
Ecol Evol ; 12(9): e9296, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36177142

RESUMEN

Ecosystem functions are heavily dependent on the functional composition of the plant community, i.e., the functional traits of plants forming the community. This, on the one hand, depends on plant occurrence, but on the other hand, depends on the intraspecific variability of functional traits of the species, which are influenced by climate and nutrient availability and affected by plant-plant interactions. To illustrate that, we studied the effects of drought and nitrogen addition (+ N), two important abiotic variables which are changing with ongoing global change, as well as their combined effect on the functional responses of grassland communities in semi-arid environments of Northern Africa comprising of natural and invasive species. We conducted an experiment where we planted three native species and one invasive plant species in artificial communities of five individuals per species per plot. We exposed these communities to four different treatments: a drought treatment, an N-addition treatment, the combination between drought and N-addition, as well as a control. To assess the performance of plants within treatments, we measured selected plant functional traits (plant height, specific leaf area [SLA], leaf dry matter content [LDMC], N content of the leaves [Nmass], specific root length [SRL], and root diameter) for all individuals occurring in our plots, and additionally assessed the above and belowground biomass for each plant individual. We found that the invasive species showed a higher performance (higher biomass accumulation, taller plants, higher SLA, Nmass, SRL, and root diameter as well as lower LDMC) than the native species under drought conditions. The invasive species was especially successful with the combined impact of drought + N, which is a likely scenario in ongoing global change for our research area. Thus, plant functional traits might be a key factor for the invasion success of plant species which will be even more pronounced under ongoing global change.

7.
Plants (Basel) ; 10(11)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34834774

RESUMEN

Land-use changes have huge impacts on natural vegetation, especially megaprojects, as the vegetation layer is destroyed in the course of construction works affecting the plant community composition and functionality. This large-scale disturbance might be a gateway for the establishment of invasive plant species, which can outcompete the natural flora. In contrast, species occurring in the area before the construction are not able to re-establish. In this study, we analyzed the impact of a pipeline construction on a wetland nature reserve located in northern Egypt. Therefore, we analyzed the plant species occurrence and abundance and measured each plant species' traits before the construction in 2017 as well as on multiple occasions up to 2 years after the construction had finished on altogether five sampling events. We found that the construction activity led to the establishment of an invasive species which previously did not occur in the area, namely, Imperata cylindrica, whereas five species (Ipomoea carnea, Pluchea dioscoridis, Polygonum equisetiforme, Tamarix nilotica, and Typha domingensis) could not re-establish after the disturbance. The functionality of ecosystems assessed via the analysis of plant functional traits (plant height, specific leaf area, and leaf dry matter content) changed within species over all sampling events and within the community showing a tendency to approximate pre-construction values. Functional dispersion and Rao's quadratic diversity were higher after the megaproject than before. These findings are important to capture possible re-establishment and recovery of natural vegetation after construction and raise awareness to the impact of megaprojects, especially in areas which are high priority for conservation.

8.
Int J Oral Maxillofac Surg ; 50(2): 163-170, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32536459

RESUMEN

Protease-activated receptor 1 (PAR1) is known as a thrombin receptor. Recent studies have reported PAR1 expression in various malignancies; however, its role in oral squamous cell carcinoma (OSCC) requires clarification. A previous study showed that down-regulation of ΔNp63, a homolog of p53, augments PAR1 expression in OSCC. In the present study, the association of PAR1 expression with clinicopathological findings in OSCC was examined retrospectively. Expression of PAR1, thrombin, and ΔNp63 was examined immunohistochemically in OSCC specimens. Patients were divided into three groups based on the expression pattern of PAR1 at the invasive front: group A, PAR1-negative in both cancer and stromal cells; group B, positive in stromal cells but negative in cancer cells; group C, positive in both cancer and stromal cells. Histologically high-grade tumours were significantly more common in group C. Patients in group C had the highest incidence rate of nodal metastasis (P<0.001) and a lower survival rate (P=0.085) than those in the other groups. At the invasive front, in group C, thrombin was expressed but ΔNp63 expression was weak. These results indicate that increased PAR1 expression in both cancer and stromal cells could be a useful predictive marker of nodal metastasis and that ΔNp63 is involved in regulating PAR1 expression.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Regulación hacia Abajo , Humanos , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello
9.
J Clin Invest ; 95(5): 1994-2003, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7738166

RESUMEN

Various growth factors are suggested to be involved in gastric mucosal repair. Our previous studies have shown that exogenous hepatocyte growth factor (HGF) has a proliferative effect on gastric epithelial cells. In the present study, comparison of the maximum proliferative effects and the optimum concentrations of several growth factors revealed that HGF was the most potent mitogen for gastric epithelial cells, as is the case for hepatocytes. Restitution of gastric epithelial cell monolayers was assessed using a round wound restitution model. HGF was the most effective agent for facilitating gastric epithelial restitution among those tested. A binding assay revealed specific binding of HGF to its receptor on gastric epithelial cells. Northern blot analysis confirmed the expression of specific HGF receptor mRNA (c-met) by gastric epithelial cells but not by gastric fibroblasts. To investigate endogenous HGF production, we determined the effect of gastric fibroblast-conditioned medium on epithelial proliferation and restitution. The conditioned medium produced similar effects to HGF and its activity was neutralized by an anti-HGF antibody. In addition, expression of HGF mRNA was detected in gastric fibroblasts but not in gastric epithelial cells. Our immunohistochemical study confirmed these in vitro data by means of demonstrating the existence and localization of HGF at human native gastric mucosa. HGF was localized at fibroblasts under the epithelial cell layer around gastric ulcers. These results suggest that HGF may be a potent endogenous promotor of gastric epithelial cell proliferation and migration, and may contribute to gastric mucosal repair through a paracrine mechanism.


Asunto(s)
Mucosa Gástrica/efectos de los fármacos , Factor de Crecimiento de Hepatocito/biosíntesis , Factor de Crecimiento de Hepatocito/farmacología , Animales , Secuencia de Bases , Northern Blotting , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Cartilla de ADN , Relación Dosis-Respuesta a Droga , Factor de Crecimiento Epidérmico/farmacología , Células Epiteliales , Epitelio/efectos de los fármacos , Epitelio/fisiología , Femenino , Fundus Gástrico , Mucosa Gástrica/citología , Mucosa Gástrica/fisiología , Factor de Crecimiento de Hepatocito/fisiología , Humanos , Insulina/farmacología , Cinética , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-met , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Conejos , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Recombinantes/farmacología , Timidina/metabolismo
10.
Biochim Biophys Acta ; 1356(2): 198-206, 1997 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-9150277

RESUMEN

Caffeine is known to stimulate gastric acid secretion, but, the effects of caffeine on gastric mucus secretion have not been clarified. To elucidate the action of caffeine on gastric mucin-producing cells and its underlying mechanism, the effects of caffeine on mucus glycoprotein secretion and agonist-induced [Ca2+]i mobilization were examined in human gastric mucin secreting cells (JR-I cells). The measurement of [Ca2+]i using Indo-1 and the whole cell voltage clamp technique were applied. Mucus glycoprotein secretion was assessed by release of [3H]glucosamine. Caffeine by itself failed to increase [Ca2+]i and affect membrane currents, while it dose-dependently inhibited agonist (acetylcholine (ACh) or histamine)-induced [Ca2+]i rise, resulting in inhibiting activation of Ca2+-dependent K+ current (I(K.Ca)) evoked by agonists. The effect of caffeine was reversible, and the half maximal inhibitory concentration was about 0.5 mM. But, caffeine did not suppress [Ca2+]i rise and activation of I(K.Ca) induced by A23187 or inositol trisphosphate (IP3). Theophylline or 3-isobutyl-1-methyl-xanthine (IBMX) did not mimic the effect of caffeine. Caffeine failed to stimulate mucus secretion, while it significantly decreased ACh-induced mucus secretion. These results indicate that caffeine selectively inhibits agonist-mediated [Ca2+]i rise in human gastric epithelial cells, probably through the blockade of receptor-IP3 signaling pathway, which may affect the mucin secretion.


Asunto(s)
Cafeína/farmacología , Calcio/metabolismo , Mucosa Gástrica/efectos de los fármacos , Moco/metabolismo , Calcimicina , Mucosa Gástrica/metabolismo , Humanos , Indoles , Fosfatos de Inositol , Mucinas/análisis , Moco/química , Espectrometría de Fluorescencia , Células Tumorales Cultivadas
11.
J Gen Physiol ; 102(4): 667-92, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8270909

RESUMEN

The effects of acetylcholine (ACh) and histamine (His) on the membrane potential and current were examined in JR-1 cells, a mucin-producing epithelial cell line derived from human gastric signet ring cell carcinoma. The tight-seal, whole cell clamp technique was used. The resting membrane potential, the input resistance, and the capacitance of the cells were approximately -12 mV, 1.4 G ohms, and 50 pF, respectively. Under the voltage-clamp condition, no voltage-dependent currents were evoked. ACh or His added to the bathing solution hyperpolarized the membrane by activating a time- and voltage-independent K+ current. The ACh-induced hyperpolarization and K+ current persisted, while the His response desensitized quickly (< 1 min). These effects of ACh and His were mediated predominantly by m3-muscarinic and H1-His receptors, respectively. The K+ current induced by ACh and His was inhibited by charybdotoxin, suggesting that it is a Ca(2+)-activated K+ channel current (IK.Ca). The measurement of intracellular Ca2+ ([Ca2+]i) using Indo-1 revealed that both agents increased [Ca2+]i with similar time courses as they increased IK.Ca. When EGTA in the pipette solution was increased from 0.15 to 10 mM, the induction of IK.Ca by ACh and His was abolished. Thus, both ACh and His activate IK.Ca by increasing [Ca2+]i in JR-1 cells. In the Ca(2+)-free bathing solution (0.15 mM EGTA in the pipette), ACh evoked IK.Ca transiently. Addition of Ca2+ (1.8 mM) to the bath immediately restored the sustained IK.Ca. These results suggest that the ACh response is due to at least two different mechanisms; i.e., the Ca2+ release-related initial transient activation and the Ca2+ influx-related sustained activation of IK.Ca. Probably because of desensitization, the Ca2+ influx-related component of the His response could not be identified. Intracellularly applied inositol 1,4,5-trisphosphate (IP3), with and without inositol 1,3,4,5-tetrakisphosphate (IP4), mimicked the ACh response. IP4 alone did not affect the membrane current. Under the steady effect of IP3 or IP3 plus IP4, neither ACh nor His further evoked IK.Ca. Intracellular application of heparin or of the monoclonal antibody against the IP3 receptor, mAb18A10, inhibited the ACh and His responses in a concentration-dependent fashion. Neomycin, a phospholipase C (PLC) inhibitor, also inhibited the agonist-induced response in a concentration-dependent fashion. Although neither pertussis toxin (PTX) nor N-ethylmaleimide affected the ACh or His activation of IK,Ca, GDP beta S attenuated and GTP gamma S enhanced the agonist response.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Acetilcolina/farmacología , Calcio/fisiología , Mucosa Gástrica/fisiología , Histamina/farmacología , Potasio/fisiología , Calcio/metabolismo , Línea Celular , Conductividad Eléctrica , Proteínas de Unión al GTP/fisiología , Mucosa Gástrica/citología , Mucosa Gástrica/efectos de los fármacos , Humanos , Inositol 1,4,5-Trifosfato/fisiología , Membranas Intracelulares/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Sistemas de Mensajero Secundario
12.
Ann N Y Acad Sci ; 936: 526-30, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11460510

RESUMEN

We found a novel genetic abnormality, heterozygous C-->T nucleotide substitution at position -1138 bp in the 5'-flanking region of the fibrinogen A alpha gene, in patients with hypofibrinogenemia. Luciferase reporter assay using the pGL3-basic vector and CHO cells indicates that the transcriptional activity of a vector incorporated with -1138T was reduced to one-third that of a vector incorporated with -1138C. These results suggest that the region adjacent to the -1138C bp of the 5'-flanking region of the fibrinogen A alpha gene is one of the most crucial sites for the transcription of the fibrinogen A alpha gene.


Asunto(s)
Fibrinógeno/genética , Heterocigoto , Mutación Puntual , Anciano , Anciano de 80 o más Años , Animales , Células CHO , Cricetinae , Genes Reporteros , Humanos , Luciferasas/genética , Masculino , Reacción en Cadena de la Polimerasa
13.
Eur J Pharmacol ; 259(2): 143-50, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-7957608

RESUMEN

Azelastine [4-(p-chlorobenzyl)-2-(hexahydro-1-methyl -1H-azepin-4-yl)-1-(2H)-phthalazinone hydrochloride], an anti-allergic agent, inhibited the high K(+)-induced contraction in tracheal smooth muscle cells isolated from the guinea-pig. In order to investigate the ionic mechanisms, we examined the effects of azelastine on membrane currents, using the tight-seal whole cell voltage clamp technique. Azelastine (1-100 microM) caused an inhibition of the Ba2+ inward current (IBa) through the voltage-dependent L-type Ca2+ channel in a concentration-dependent manner. The inhibitory effect of azelastine on IBa was fully reversible. The IC50 value for azelastine-induced inhibition of IBa was approximately 8 microM, and 100 microM azelastine completely suppressed IBa. Azelastine exerted mainly a tonic block of IBa but did not show use dependence. Azelastine (10 microM) shifted the quasi-steady-state inactivation curve of IBa to more negative membrane potentials by approximately -20 mV, suggesting that the inhibitory effect of azelastine on IBa was voltage-dependent. In addition, azelastine produced inhibitory actions on other membrane currents (i.e. the voltage-dependent transient outward K+ current and the Ca(2+)-activated oscillatory K+ current) at doses higher than 10 microM. These results suggest that azelastine inhibits the voltage-dependent L-type Ca2+ current in single tracheal smooth muscle cells, which may contribute to the anti-allergic actions of azelastine in airways.


Asunto(s)
Músculo Liso/efectos de los fármacos , Ftalazinas/farmacología , Tráquea/efectos de los fármacos , Animales , Calcio/antagonistas & inhibidores , Membrana Celular/efectos de los fármacos , Membrana Celular/fisiología , Electrofisiología , Cobayas , Antagonistas de los Receptores Histamínicos H1 , Técnicas In Vitro , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso/fisiología , Técnicas de Placa-Clamp , Potasio/antagonistas & inhibidores , Tráquea/fisiología
14.
Eur J Pharmacol ; 294(2-3): 625-35, 1995 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-8750727

RESUMEN

To elucidate the mechanisms of estrogens-induced relaxation effects on vascular smooth muscle cells, the effects of estrogens and the related hormones were examined in cultured rat thoracic aortic smooth muscle cell lines (A7r5), using the whole-cell voltage clamp technique. The patch pipette was filled with 140 mM CsCl- or KCl-containing internal solution. With CsCl-internal solution, 17beta-estradiol and synthetic estrogens, ethynylestradiol and diethylstilbestrol (0.1-30 mu M) inhibited the Ba2+ inward current (IBa) through the voltage-dependent L-type Ca2+ channel in a concentration-dependent and reversible manner. The potency of the inhibitory effects on IBa was 17beta-estradiol < ethynylestradiol < diethylstilbestrol. 17beta-Estradiol (10 mu M) appeared to reduce the maximal conductance of IBa with only a slight shift of voltage-dependency of inactivation and to affect IBa in a use-independent fashion. On the other hand, testosterone and progesterone (30 mu M) failed to affect IBa. At a holding potential of -40 mV, both vasopressin and endothelin-1 (100 nM) activated a long-lasting inward current. After endothelin-1 (100 nM) activated the current, the additional application of vasopressin (100 nM) could not induce it furthermore, suggesting that each agonist activates the same population of the channels. The reversal potential of the current was about 0 mV and was not significantly altered by replacement of [Cl-]i or [Cl-]0 and the inward current was also observed even when extracellular cations are Ca2+, proposing that it was a Ca2+-permeable non-selective cation channel (IN.S.). La3+ or Cd2+ (1 nM) completely abolished IN.S., however, nifedipine (10 mu M) failed to inhibit it at all. Diethylstilbestrol (1-30 mu M) suppressed the IN.S. evoked by both endothelin-1 and vasopressin in a concentration-dependent manner, while 17beta-estradiol, ethynylestradiol, progesterone and testosterone (30 mu M) failed to inhibit it significantly. In addition, at a holding potential of +0 mV, 17beta-estradiol by itself did not affect the holding currents, and did not inhibit K+ currents evoked by endothelin-1 or vasopressin, possibly due to the Ca2+ release from the storage sites. These results suggest that 17beta-estradiol may play a role in regulating vascular tone, selectively by inhibiting the voltage-dependent L-type Ca2+ current in vascular smooth muscle cells.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Estradiol/farmacología , Músculo Liso Vascular/efectos de los fármacos , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/fisiología , Línea Celular , Perros , Endotelinas/farmacología , Canales de Potasio/efectos de los fármacos , Ratas , Vasopresinas/farmacología
15.
J Gastroenterol ; 29(2): 208-13, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8012511

RESUMEN

A case of Churg-Strauss syndrome with multiple perforations of the small intestine is described. A 31-year-old woman was admitted with a complaint of epigastric pain. She had a history of bronchial asthma. One week before admission, white blood cell count was 20,800/mm3 with 59% eosinophils. Neurological examination on admission disclosed mononeuritis multiplex with paresthesia in both the lower and upper extremities. At colonoscopy, there were scattered aphthous ulcers in the colon. Ophthalmological examination revealed allergic conjunctivitis. After admission, hypereosinophilia increased to as high as 36,000/mm3. Oral administration of prednisolone (60 mg/day) was begun. On the 3rd day of the treatment, the eosinophil count decreased dramatically, to 400/mm3, while severe abdominal pain developed. Since abdominal X-ray film revealed free air in the abdominal cavity, emergency laparotomy was performed and multiple intestinal ulcers with perforations were found. Partial ileectomy was performed. Pathological findings of the resected specimen were interpreted as a necrotizing angiitis with extravascular granuloma. Since the operation, the patient has been asymptomatic, except for neurological symptoms. Hypereosinophilia has decreased without treatment to counts averaging 270/mm3, within 3 months. On the basis of the clinical features and histopathological findings, a diagnosis of Churg-Strauss syndrome was established.


Asunto(s)
Síndrome de Churg-Strauss/complicaciones , Enfermedades del Colon/complicaciones , Enfermedades del Íleon/complicaciones , Perforación Intestinal/complicaciones , Neuritis/complicaciones , Adulto , Síndrome de Churg-Strauss/patología , Femenino , Granuloma/complicaciones , Granuloma/patología , Humanos , Enfermedades del Íleon/patología , Perforación Intestinal/patología , Enfermedades del Sistema Nervioso Periférico/complicaciones , Úlcera/complicaciones , Úlcera/patología
16.
J Gastroenterol ; 29(5): 642-6, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8000514

RESUMEN

A 63-year old woman who had experienced melena for 2 weeks was admitted to Tokyo University Hospital. Gastric adenocarcinoma was diagnosed endoscopically and histologically, and a total gastrectomy was performed soon thereafter. Pathological examination of the resected stomach revealed choriocarcinoma of the stomach. Although chemotherapy was administered after surgery, she died 3 months after admission. Autopsy confirmed the diagnosis of primary gastric choriocarcinoma, a rare, but highly malignant tumor. It is characteristic; macroscopically it forms a necrotic mass with bleeding, and microscopically it often consists of adenocarcinoma and choriocarcinoma. Since its prognosis is extremely poor, we must take into account the possibility of primary gastric choriocarcinoma when a hemorrhagic gastric tumor with necrosis is found.


Asunto(s)
Coriocarcinoma/patología , Neoplasias Gástricas/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad
17.
Naunyn Schmiedebergs Arch Pharmacol ; 344(1): 133-6, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1775189

RESUMEN

The effect of coenzyme Q10 (CoQ10) on the cyanide (CN-)-induced ATP-sensitive K+ channel current (KATP) was examined in single atrial myocytes, using the patch clamp technique. Superfusion of the cells with a CN-/low glucose bathing solution induced an outward current in the whole-cell clamp condition. Glibenclamide (1 microM) abolished this current, indicating that the current was carried through the KATP channel. After steady-state activation by CN-, pinacidil (a KATP channel opener, 300 microM) failed to further increase the current. In cell-attached patches, CN-, when applied to the bath, induced bursting openings of an 80 pS channel (the KATP channel). In cells preincubated for 30 min in a solution containing CoQ10 (100 micrograms/ml), CN(-)-activation of the KATP channel was markedly attenuated both at the whole cell and at the single channel level. At the steady-state effect of CN- in CoQ10-treated cells, pinacidil (300 microM) activated the current to the maximum level achieved by CN- in the control cells. These results suggest that CoQ10 reduces in the CN(-)-induced KATP current not by affecting the channel itself but by preventing depletion of intracellular ATP caused by CN-.


Asunto(s)
Adenosina Trifosfato/fisiología , Cianuros/farmacología , Corazón/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Ubiquinona/análogos & derivados , Adenosina Trifosfato/biosíntesis , Animales , Coenzimas , Cobayas , Miocardio/citología , Miocardio/metabolismo , Miocardio/ultraestructura , Factores de Tiempo , Ubiquinona/farmacología
18.
Acta Otolaryngol ; 103(3-4): 312-7, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3577763

RESUMEN

The volume of nasal secretion is so small that it is difficult to measure. We placed a thread on the anterior surface of the inferior turbinate to measure the volume of nasal secretion in normal subjects and patients with nasal allergy. In 24 normal subjects, the average nasal secretion amounted to 1.09 microliter/min. In 48 patients with nasal allergy, the volume of nasal secretion (1.94 microliter/min) decreased significantly after nasal spraying: the subjective symptoms of sneezing, rhinorrhea, nasal obstruction, inconvenience in daily life and the objective signs such as watery rhinorrhea abated. The thread test results showed a good correlation with the above items in a quantitative analysis. The thread test is a simple way to measure a small volume of nasal secretion, and a useful indicator of the severity of watery rhinorrhea in patients with nasal allergy.


Asunto(s)
Mucosa Nasal/metabolismo , Rinitis Alérgica Estacional/diagnóstico , Femenino , Humanos , Masculino , Rinitis Alérgica Estacional/fisiopatología
19.
Auris Nasus Larynx ; 18(4): 343-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1820743

RESUMEN

One hundred and ninety-four patients with a sensation of ear fullness were examined with the audiometry, tympanometry, and tubotympanoaero-dynamic graphy (TTAG) as a eustachian tube ventilatory test. In 74 cases of 194, the eustachian tube dysfunction was thought to cause an ear fullness sensation and patulous tube was found in 19 patients which is more frequent than expected. Functional unbalance of the both eustachian tubes which results from minimum ventilatory disturbance on the complaining side was also thought to be one of the causes of this symptom. The eustachian tube dysfunctions like stenotic or patulous tube could not be fully diagnosed by the audiometry and tympanometry because most patients with the eustachian tube dysfunctions showed normal middle ear pressure measured by the tympanometry. From our study, it could be concluded that eustachian ventilatory test like TTAG was very available in the patient with an ear fullness feeling which is one of the most common symptoms in the otolaryngological field.


Asunto(s)
Trompa Auditiva/fisiología , Pruebas de Impedancia Acústica , Adulto , Constricción Patológica/diagnóstico , Enfermedades del Oído/diagnóstico , Femenino , Humanos , Presión
20.
Water Sci Technol ; 46(11-12): 419-24, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12523788

RESUMEN

We examine the validity of pulse count of snapping shrimps for sea environmental monitoring. Snapping shrimps, which make a peculiar pulse sound, are found everywhere in the world. Pulse count can be achieved merely by recording their sounds for a few minutes by using a hydrophone without special biological knowledge. From field surveys and laboratory experiments, we found that the pulse count depends on water temperature when sea environment is normal, and it falls due to the occurrence of oxygen-deficient water. The results show that this method can be a useful index of the effect of water pollution on benthic animals in fixed-point observation.


Asunto(s)
Comunicación Animal , Decápodos , Monitoreo del Ambiente/métodos , Contaminantes del Agua/efectos adversos , Acústica , Animales , Conducta Animal , Oxígeno , Temperatura
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