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1.
αB-crystallin, a major component of the mammalian eye lens, is a small heat shock protein and molecular chaperone that is also abundant in the mammalian kidney. The present study aimed to characterize more closely the intrarenal expression and regulation of αB-crystallin in vivo and in vitro. In normal rat kidney, the expression of αB-crystallin mRNA and protein were both close to the detection limit in cortex, but increased steeply from the outer to the inner medulla where αB-crystallin constitutes approximately 2% of total tissue protein. Immunohistochemistry disclosed papillary collecting duct cells and thin limbs as the major sites for intrapapillary αB-crystallin immunoreactivity. In rats subjected to sucrose diuresis for 3 days, αB-crystallin mRNA expression was reduced by 27 and 46% in outer and inner medulla, respectively. In agreement with the results obtained in vivo, in Madine–Darby canine kidney cells, αB-crystallin mRNA and protein were induced significantly by elevating the medium osmolality to 500 mosm/kg H2O by the addition of NaCl and raffinose, and also by urea. The NaCl-induced increase in αB-crystallin expression was concentration-dependently blunted by SP600125, a specific JNK inhibitor. Overexpression of αB-crystallin in 293 cells resulted in increased tolerance to acute osmotic stress. These results indicate that αB-crystallin may be regulated by papillary interstitial tonicity in a JNK-dependent process. Moreover, the high abundance of αB-crystallin in the renal medulla may be important for cell survival in an environment characterized by extreme interstitial solute concentrations as present during antidiuresis.  相似文献   

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Peak velocity, duration and accuracy of eye movements (saccade, vergence and combined saccade–vergence eye movements) were investigated in fourteen normal children (4.5 to 12 years of age) and ten normal adults (22 to 44 years of age). Horizontal movements from both eyes were recorded simultaneously by the oculometer, a photoelectric device. Peak velocity of all eye movements, saccades, and vergence (convergence and divergence), attains adult levels by the age of 4.5 years and there is no significant change over the age range studied (4.5 to 44 years). Vergence duration is longer only in young children (below 8 years of age). The reciprocal interaction between saccade and vergence during combined movements known in adults, i.e. acceleration of the vergence by the saccade (increase of velocity and decrease of duration) and deceleration of the saccade by the vergence (decrease of velocity and increase of duration) was found to be similar in children. The accuracy of eye movements is good on average for both saccades and vergence by the age of 4.5 years, and does not change with age; an exception is the variability of saccade amplitude, which is higher in children less than 8 years old. Taken together, the results indicate early maturation of brainstem structures controlling spatio-temporal aspects of saccades, vergence and their interaction.  相似文献   

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Aug.18alll8:00一10:00,10:30一12,00At Room No.1(213)CO一CHAIRMAN Prof.Yang GuitongProf.K.TsushiyaTITLEABSTRACT PAGESDesign of femoral stem based on geometrie data Rueymo Lin,et al.····················································································……87Effieieney of weak external fields on bioel飞emieally reaeting systems A .V.Chalyi,et al.···················…  相似文献   

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TGF-β1 binds receptor II (TβRII) to exert its biological activities but its functional importance in kidney diseases remains largely unclear. In the present study, we hypothesized that TβRII may function to initiate the downstream TGF-β signalling and determine the diverse role of TGF-β1 in kidney injury. The hypothesis was examined in a model of unilateral ureteral obstructive (UUO) nephropathy and in kidney fibroblasts and tubular epithelial cells in which the TβRII was deleted conditionally. We found that disruption of TβRII inhibited severe tubulointerstitial fibrosis in the UUO kidney, which was associated with the impairment of TGF-β/Smad3 signalling, but not with the ERK/p38 MAP kinase pathway. In contrast, deletion of TβRII enhanced NF-κB signalling and renal inflammation including up-regulation of Il-1β and Tnfα in the UUO kidney. Similarly, in vitro disruption of TβRII from kidney fibroblasts or tubular epithelial cells inhibited TGF-β1-induced Smad signalling and fibrosis but impaired the anti-inflammatory effect of TGF-β1 on IL-1β-stimulated NF-κB activation and pro-inflammatory cytokine expression. In conclusion, TβRII plays an important but diverse role in regulating renal fibrosis and inflammation. Impaired TGF-β/Smad3, but not the non-canonical TGF-β signalling pathway, may be a key mechanism by which disruption of TβRII protects against renal fibrosis. In addition, deletion of TβRII also enhances NF-κB signalling along with up-regulation of renal pro-inflammatory cytokines, which may be associated with the impairment of anti-inflammatory properties of TGF-β1.  相似文献   

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Aug·18 ams,00一10:00,10,30一12:00At Room No.7(208)CO一CHAIRMAN Prof.Kong Fanliang Prof.F·KajiyaTITLEABSTRACT PAGESDevelopment of new eo laser angioplasty system MakotoKikuchi,et al.······································································,·······……262Intraeellular pH measurement of rat hippoeampal brain sliees usingsingle exeitation一dual emission fluoreseent dye,SNARF一l C.W.Lin,et…  相似文献   

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Introduction Thearterialcirculationistraditionallymodeledintwowaysneitherofwhichaloneisabletofullyaccountforitsproperties.Inthewell knowntwoelementwindkesselmodelthecirculationisviewedintermsofparal lelcapacitanceandresistancecomponents .Theresistancet…  相似文献   

7.

Introduction

Cortisol release is often associated with physiological arousal or perceived stress. Findings in adults as well as in older children and adolescents show that cortisol is also connected to sleep. Furthermore, it is assumed that high-quality sleep is a predictor of regular cortisol release throughout the day.

Objective

This review summarizes the current literature on how sleep and cortisol levels are associated in early childhood.

Methods

In order to identify studies on sleep and cortisol in young children, a structured literature search was performed in the PsychINFO, PsycARTICLES, PSYNDEX, and Google Scholar databases.

Results

A total of 14 studies could be included this review. According to the results of the reviewed publications, daily cortisol release patterns develop within the first 6 months of life. In addition, young children display a cortisol awakening response (CAR) and cortisol levels are influenced by taking naps during the day as well as by the quality of nighttime sleep.

Conclusion

After reviewing the recent findings in the literature concerning children from birth up to the age of 5 years, it can be assumed that sleep patterns and sleep are associated with cortisol secretion in early childhood. This finding could be included in the creation and further development of interventional sleep training programs.
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The integrity of our bodies is under constant threat by external forces. Blood coagulation and inflammatory pathways are important, highly efficient defence systems that support health and well-being in both normal and challenged conditions. Being potentially dangerous for the own organism, they are kept under strict control by anticoagulant and anti-inflammatory mechanisms. Coagulation and inflammatory pathways are closely integrated by extensive crosstalk and tend to function in concert. They comprise a large number of cellular and molecular actors, which interact in extremely complex manners. A basic principle governing these interactions is the mutual activation of the pathways. Thus, the activation of coagulation leads to concomitant activation of inflammatory pathways, mirrored by the initiation of coagulation by inflammatory pathways. Efficient anticoagulant systems not only keep coagulation reactions under strict control but also exert control on inflammatory reactions. During inflammation, these anticoagulant/anti-inflammatory systems are repressed allowing full activation of coagulation and inflammation. Dysregulation of the delicate balance between these systems contributes to the pathogenesis of many diseases.  相似文献   

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Muscle performance is closely related to the architecture and dimensions of the muscle–tendon unit and the effect of maturation on these architectural characteristics in humans is currently unknown. This study determined whether there are differences in musculo‐tendinous architecture between adults and children of both sexes. Fascicle length and pennation angle were measured from ultrasound images at three sites along the length of the vastus intermedius, vastus lateralis, vastis medialis and rectus femoris muscles. Muscle volume and muscle–tendon length were measured from magnetic resonance images. Muscle physiological cross‐sectional area (PCSA) was calculated as the ratio of muscle volume to optimum fascicle length. Fascicle length was greater in the adult groups than in children (P < 0.05) but pennation angle did not differ between groups (P > 0.05). The ratios between fascicle and muscle length and between fascicle and tendon length were not different (P > 0.05) between adults and children for any quadriceps muscle. Quadriceps volume and PCSA of each muscle were greater in adults than children (P < 0.01) but the relative proportion of each head to the total quadriceps volume was similar in all groups. However, the difference in PCSA between adults and children (men ~ 104% greater than boys, women ~ 57% greater than girls) was greater (P < 0.05) than the difference in fascicle length (men ~ 37% greater than boys, women ~ 10% greater than girls). It is concluded that the fascicle, muscle and tendon lengthen proportionally during maturation, thus the muscle–tendon stiffness and excursion range are likely to be similar in children and adults but the relatively greater increase in PCSA than fascicle length indicates that adult muscles are better designed for force production than children’s muscles.  相似文献   

14.
Introduction  The immune response is controlled by several inhibitory mechanisms. These mechanisms include regulatory T cells, which exist in multiple classes. Notable among these are Foxp3-expressing regulatory T cells (Treg), NKT cells, and Tr1 cells. Common to these mechanisms are inhibitory cytokines such as interleukin-10 and transforming growth factor-beta (TGF-β). TGF-β and Foxp3-expressing Treg cells are critical in maintaining self-tolerance and immune homeostasis. Discussions  The immune suppressive functions of TGF-β and Treg cells are widely acknowledged and extensively studied. Nonetheless, recent studies revealed the positive roles for TGF-β and Treg cells in shaping the immune system and the inflammatory responses. In this paper, we will discuss the role of these mechanisms in the control of immunity and autoimmunity and the mechanisms that underlie how these molecules control these responses.  相似文献   

15.
A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging.  相似文献   

16.
Y Yang  F An  Z Liu  X Zhang  M Zhou  W Li  X Hao  CS Lee  X Zhang 《Biomaterials》2012,33(31):7803-7809
We report a new strategy of using carrier-free pure near-infrared (NIR) dye nanoparticles (NPs) to achieve highly luminescent NIR fluorescent probes for in?vitro and in?vivo imaging. Bis(4-(N-(2-naphthyl)phenylamino) phenyl)-fumaronitrile (NPAPF) NPs are shown to exhibit favorable biocompatibility, wide-range pH stability (pH 4-10) and much more superior photostability than conventional dyes. Importantly, the combined merits of high dye loading content and aggregation-induced emission enhancement properties, endow the NIR probes with high brightness and a high quantum yield up to 14.9%. The NPAPF NPs can be readily conjugated with folic acid for targeted in?vitro cell imaging. Applications of the NPs probes in high efficiency in?vivo and ex?vivo imaging were successfully demonstrated. Intense fluorescent signals of NPAPF NPs can be distinctly, selectively and spatially resolved in tumor sites with ultrahigh sensitivity, even with 5?ms exposure time, due to the preferentially accumulation of NPs in tumor sites through passive enhanced permeability and retention effect. The totality of results clearly demonstrate the exciting potential of the functionalized NPAPF NPs as a NIR fluorescent probe for in?vitro and in?vivo imaging and diagnostics.  相似文献   

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The “in vitro” test of histamine release induced in the leukocytes of atopic subjects selected according to specific criteria would seem to be much more accurate to study the histamine releasing characteristics of intravenous agents than the “in vivo” study in patients who have to be anaesthetised. Moreover, different concentrations of the test drug may be used, and thus the threshold for histamine release may be compared. It is the test which we recommend for investigating new drugs. However, it is lengthy and expensive; it can therefore not be recommended as a routine preoperative investigation.  相似文献   

19.
The progression of cancer from non-metastatic to metastatic is the critical transition in the course of the disease. The epithelial to mesenchymal transition (EMT) is a mechanism by which tumor cells acquire characteristics that improve metastatic efficiency. Targeting EMT processes in patients is therefore a potential strategy to block the transition to metastatic cancer and improve patient outcome. To develop models of EMT applicable to in vitro and in vivo settings, we engineered NCI-H358 non-small cell lung carcinoma cells to inducibly express three well-established drivers of EMT: activated transforming growth factor β (aTGFβ), Snail or Zeb1. We characterized the morphological, molecular and phenotypic changes induced by each of the drivers and compared the different end-states of EMT between the models. Both in vitro and in vivo, induction of the transgenes Snail and Zeb1 resulted in downregulation of epithelial markers and upregulation of mesenchymal markers, and reduced the ability of the cells to proliferate. Induced autocrine expression of aTGFβ caused marker and phenotypic changes consistent with EMT, a modest effect on growth rate, and a shift to a more invasive phenotype. In vivo, this manifested as tumor cell infiltration of the surrounding mouse stromal tissue. Overall, Snail and Zeb1 were sufficient to induce EMT in the cells, but aTGFβ induced a more complex EMT, in which changes in extracellular matrix remodeling components were pronounced.  相似文献   

20.
We used direct calorimetry and respirometry to measure the total rate of heat loss (Qsigma) and of oxygen consumption (VO2) in guinea pigs in 1-atm (0.1 MPa) air and at 10-60 atm in either heliox (98% He, 2% O2) or hydrox (98% H2, 2% O2). Our objective was to determine if the physiological responses to these two gas mixtures were different and, if so, whether the differences were attributable to the thermal characteristics of the gases alone or were confounded by additional mechanisms. At 10-40 atm, Qsigma and VO2 were not significantly different in the two gas mixtures, whereas at 60 atm, Qsigma and VO2 were significantly higher in heliox than in hydrox. The VO2/Qsigma ratio suggested that the animals were not in thermal equilibrium in hyperbaria. Based solely on the differing thermal properties of the gas mixtures, a mathematical model predicted a Qsigma that was higher in hydrox than in heliox at all pressures. Two plausible explanations are suggested: one is an adaptive lowering of the surface temperature as a physiological response of the animal to the thermally more stressful hydrox environment, and the other is related to the narcotic suppression of the animal's activity by hydrox.  相似文献   

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