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21.
The authors prospectively studied changes in the optic disc and visual field associated with intraocular pressure (IOP) reduction for one year after surgery in 12 primary open-angle glaucoma eyes of 7 patients who underwent trabeculectomy because of elevated IOP despite maximum tolerable medical therapy and whose cup volume was demonstrated to be decreased at 3 or 6 months after surgery. Topographic parameters including C/D ratio, rim area and cup volume were determined by the Optic Nerve Head Analyzer plus (Rodenstock). The 30-2 central threshold field was obtained with a Humphrey Field Analyzer at the same time. Mean deviation (MD), corrected pattern standard deviation (CPSD) and total deviation (TD) were used to evaluate visual field changes. Significant improvement of C/D ratio, rim area and cup volume and significant IOP reduction were noted at 1 year after surgery as compared with preoperative baseline value (p less than 0.01). Also the MD was significantly decreased at 1 year after surgery, compared with the preoperative baseline value (p less than 0.05). There was a significant negative correlation between the preoperative MD and the percent change of the MD at 1 year after surgery (r = -0.80, p less than 0.01). Our results suggest that the decrease of optic disc cupping can persist over one year after surgery and that the early visual field defects in glaucoma eyes can gradually improve in association with the decrease of cupping. 相似文献
22.
Ultrastructural morphology of early cellular changes in the synovium of primary synovial chondromatosis. 总被引:2,自引:0,他引:2
Synovial tissues taken from 13 cases of synovial chondromatosis (SC) were examined by light and electron microscopy. In three of the 13 cases, early cellular changes were observed by electron microscopy. Most of the foci were independently situated within an accumulation of fine, homogenous chondroid matrix in the sublining area of the synovium. Basal laminalike material was observed in these cells. Because this material was not apparent in the mature cartilage cells, the authors postulate that the basilaminar material affects cellular cytodifferentiation in SC during the initial phase of the disease. Ultrastructurally, these cells are morphologically similar to myofibroblasts. However, proliferation of paravascular cells with distinct basal laminae and activated secretory abilities was observed around some of the vessels. These paravascular cells may be the precursor cells of the prechondroblastic cells with basal laminalike material seen in SC. 相似文献
23.
Kazuhiko Sonoyama Haruaki Ninomiya Osamu Igawa Yasuhiro Kaetsu Yoshiyuki Furuse Toshihiro Hamada Junichiro Miake Peili Li Yasutaka Yamamoto Kazuhide Ogino Akio Yoshida Shin-ichi Taniguchi Yasutaka Kurata Satoshi Matsuoka Toshio Narahashi Goshi Shiota Yoshihisa Nozawa Hiroaki Matsubara Masatsugu Horiuchi Yasuaki Shirayoshi Ichiro Hisatome 《Hypertension research》2006,29(11):923-934
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells. 相似文献
24.
Clinical effects of percutaneous cardiopulmonary support in severe heart failure: early results and analysis of complications. 总被引:2,自引:0,他引:2
Shigeru Sakamoto Junichi Matsubara Toshiaki Matsubara Yasuhiro Nagayoshi Shinji Shono Hisateru Nishizawa Masaaki Kanno Katsunori Takeuchi Toshimichi Nonaka Jun Kyosawa 《Annals of thoracic and cardiovascular surgery》2003,9(2):105-110
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage. 相似文献
25.
T. Tamura M. Matsubara K. Hasegawa K. Ohmori A. Karasawa 《Clinical and experimental allergy》2005,35(1):97-103
BACKGROUND: Olopatadine hydrochloride (olopatadine; Allelock) is one of the second-generation antihistamines that are treated for allergic disorders such as rhinitis, urticaria and eczema dermatitis. Olopatadine has recently been shown to have inhibitory effects on the chronic contact hypersensitivity induced by repeated application of oxazolone in mice. Although topical steroids have widely been prescribed for atopic dermatitis, a relapse often occurs within several days after discontinuation of their prolonged use. OBJECTIVES: We investigated the possible efficacy of olopatadine against the relapse after discontinuation of prolonged use of topical prednisolone in the Balb/c mice with oxazolone-induced chronic contact hypersensitivity. METHODS: Mice with the chronic contact hypersensitivity induced by repeated application of oxazolone were treated with olopatadine as a sequential therapeutic agent. The effects of olopatadine were quantified by measurements of ear-swelling, and levels of cytokines and histamine in the lesioned ear. Results Topical prednisolone (0.05 mg/ear/day) significantly inhibited the increases in ear swelling and production of IL-1beta, IL-4, IL-18, granulocyte-macrophage colony-stimulating factor (GM-CSF) and histamine. However, after discontinuation of the treatment with topical prednisolone, the inflammation relapsed and the IL-4 level exceeded the control one. The sequential treatment with olopatadine (10 mg/kg/day) after discontinuation of the treatment with topical prednisolone alone, or topical prednisolone with olopatadine, significantly inhibited the increases in ear swelling and levels of IL-1beta, IL-4, IL-18, GM-CSF, nerve growth factor and histamine. CONCLUSIONS: These results indicate that olopatadine is an antihistamine agent having inhibitory activities against the rebound phenomenon following the discontinuation of topical steroid therapy. Olopatadine is thus expected to be a sequential therapeutic agent after discontinuation of the chronic treatment with a topical steroid. 相似文献
26.
Two-dimensional maps of orientation and direction preference were made in area 18 of the cat's visual cortex using multiple electrode penetrations 150-300 micron apart. The maps were then analyzed by autocorrelation and Fourier transformation. The power spectrum of the orientation map was sharply peaked below the theoretical cutoff frequency for the sampling function (the pattern of electrode penetrations) used to obtain the map. This suggested that it would be possible to interpolate orientation values between the sample points in the cortex. This was done and the resulting fine-grain maps of orientation preference were studied. Empirical testing showed that the interpolated orientation values were accurate to within +/- 30 degrees. Study of the fine-grain maps showed that iso-orientation domains for broad orientation ranges (0 degrees-90 degrees) were branching bands running from an anterolateral to a posteromedial direction across the surface of the cortex with a periodicity of 1.25 +/- 0.13 mm. Domains for smaller orientation ranges (0 degrees-30 degrees) were periodically spaced, but somewhat irregularly shaped patches. The orientation maps contained numerous point singularities where orientation changed discontinuously. These were spaced about 750 micron apart and most were surrounded by a single 180 degrees cycle of orientations. Autocorrelation analysis of the maps of preferred direction revealed local clustering that extended over a distance of 250-300 micron, but spectral analysis failed to reveal any evidence of periodicity. The absence of periodicity was probably due to a relatively large number of 180 degrees reversals in the map of direction preference, which do not affect the continuity of the orientation map and are not sufficiently numerous to destroy local continuity in the direction map. It is shown that the direction map, if it is to be as continuous as possible, must nevertheless contain lines across which direction preference reverses by 180 degrees. These lines run from one orientation singularity to another. Evidence that the direction map approaches this degree of continuity is presented. 相似文献
27.
28.
Select types of supporting cell in the inner ear express aquaporin-4 water channel protein 总被引:14,自引:0,他引:14
Yutaka Takumi Erlend Arnulf Nagelhus Jo Eidet Atsushi Matsubara Shin-ichi Usami Hideichi Shinkawa Søren Nielsen Ole Petter Ottersen 《The European journal of neuroscience》1998,10(12):3584-3595
Aquaporins (AQPs) confer a high water permeability on cell membranes and play important parts in secretory and absorptive epithelia in kidney and other organs. Here we investigate whether AQPs are expressed in the sensory epithelia of the inner ear, where a precise volume regulation is crucial. By use of specific antibodies it was found that the inner ear contains AQP1 and 4 while being devoid of detectable levels of AQP2, 3 or 5. Immunofluorescence and postembedding immunogold labelling revealed a strictly non-epithelial distribution of AQP1, confirming previous data. In contrast, AQP4 protein and mRNA (visualized by in situ hybridization) were concentrated in select types of supporting cell, including Hensen's cells and inner sulcus cells. Immunogold particles signalling AQP4 were confined to the basolateral plasma membrane of Hensen's cells and to the basal plasma membrane of Claudius cells and inner sulcus cells. AQP4 was also found in supporting cells of the vestibular end organs, but was absent from transitional epithelial cells and dark cells. Strong labelling for AQP4 and AQP4-mRNA was associated with the central part of the cochlear and vestibular nerves. Hair cells were consistently unlabelled. Our findings indicate that AQP4 may facilitate osmotically driven water fluxes in the sensory epithelia of the inner ear and thus contribute to the volume and ion homeostasis at these sites. 相似文献
29.
SOLANUM ACULEATISSIMUM (Solanaceae) plants, which were cultivated in the open field, were harvested once a month from June 1985 to January 1986. The growth matter and content of steroid saponins, aculeatiside A and B which are precursors of steroid hormones in root, were then measured in order to examine their seasonal variations during one vegetation period. The aerial parts of the plants died of chill and frost in January. In November the dry weight of root reached the maximum, and the content of steroid saponins was more than 10% and showed a maximum. The yield of steroid saponins per plant was greatest in November. These results suggest that November is the appropriate time for harvest, and that S. ACULEATISSIMUM can be more useful than the DIOSCOREA species which is now used as a source plant of steroid hormones. 相似文献
30.
Miura-Yokota Y Matsubara Y Ebihara T Hattori S Irie S 《Connective tissue research》2004,45(2):109-121
Collagen purified from the mantle muscle of the Japanese common squid, Todarodes pacificus, showed autodegradation during incubation under acidic conditions at 25 degrees C, without the addition of exogenous enzymes. This suggests that the collagenolytic proteases bind to collagen tightly through the steps of collagen preparation. Collagenolytic activity also was detected in a crude extract of mantle muscle, and leupeptin and E-64 were observed to inhibit collagenolytic activity within the collagen fraction and muscle extract. We purified these collagenolytic cysteine proteases by leupeptin column chromatography and cellulose acetate membrane electrophoresis. Optimal enzymatic activity was observed at pH 3.5, and collagenolytic activity was completely suppressed at neutral or alkaline pH. The purified enzymes were 28 kDa and 25 kDa in size, and both had gelatinolytic activity, as detected by gelatin zymography, and cut the specific site of denatured collagen alpha chain. The purified enzymes degraded squid collagen at 25 degrees C, which is 2.5 degrees lower than the temperature at which squid collagen normally denatures; however, the proteases were ineffective at 20 degrees C. Interestingly, the isolated proteases were capable of digesting both squid and bovine gelatin. In this article, we describe collagenolytic cysteine proteases that bind to the collagen of Todarodes pacificus, thereby digesting it by attacking microunfolding regions generated by incubation 2-3 degrees C below the denaturation temperature. 相似文献