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Extrapontine and central pontine myelinolysis (EPM/CPM) are rare events in pediatric neurology but can have devastating consequences. They are most commonly associated with rapid correction of hyponatremia but have been reported in other situations as well. This condition is relatively more common in adult neurology, not surprisingly, as alcoholism and associated malnutrition are often predisposing conditions. There have been few case reports in children with regards to this. We describe a 4-year old who presented with focal neurological deficits in the setting of diabetic ketoacidosis and the ensuing underlying osmotic imbalances. The patient made a remarkable recovery with no deficits of note-cognitive or motor. To our knowledge this is the youngest case reported so far of EPM in a child with diabetic ketoacidosis. The history of the condition, early animal experiments, clinicopathologic correlates, previous case reports and other scenarios in which this unusual event can occur are discussed--though the exact pathogenesis of this condition still remains unclear. We hope to bring to the attention of clinicians caring for children in the acute care setting, the importance of gradual correction of serum osmolality to reduce morbidity and mortality. 相似文献
23.
明胶降解物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响 总被引:1,自引:0,他引:1
目的 探讨组织工程心瓣膜常用人工基质材料--明胶发生降解后的产物对大鼠真皮成纤维细胞增殖及Ⅰ型胶原蛋白分泌的影响. 方法 利用酶组合技术制备明胶降解物(gelatin hydrolysate, GH),采用超滤的方法分离出低分子量明胶降解物组分(gelatin hydrolysate fraction, GHF),用于5只SD大鼠真皮成纤维细胞的体外培养.采用CCK-8活细胞计数试剂盒(Cell Counting Kit-8)检测细胞的增殖情况,ELISA试剂盒检测细胞I型胶原蛋白的分泌情况. 结果 ①GHF对细胞增殖作用的浓度效应:在0.125~1.0 mg/ml浓度范围内,GHF对细胞的促增殖作用呈现先增强后减弱的趋势,在0.25 mg/ml时,细胞增殖率最大,达到(47.54±16.35)%;②GH与GHF对细胞增殖影响比较:GH与GHF均具有促进细胞增殖的作用,且在浓度为0.25 mg/ml时,促细胞增殖作用无显著差异[(27.04±15.21)% vs (39.22±15.55)%, P=0.177];③GH与GHF对细胞分泌Ⅰ型胶原蛋白影响比较:GHF组第3天时Ⅰ型胶原分泌量为(28.06±5.60)pg/105,与空白对照的(18.24±4.52)pg/105相比,有显著差异(P=0.006),而GH组直至第6天时Ⅰ型胶原蛋白分泌量,与空白对照相比,无统计学意义(P=0.103). 结论 分子量大小不同的明胶降解物GH与GHF均具有促进大鼠真皮成纤维细胞增殖的作用,且分子量较小的GHF还具有促进细胞I型胶原分泌的功能. 相似文献
24.
选用50只新西兰白兔,2只处死后取上唇组织作为病理对照,48只采用Millard’s法修复上唇裂隙,拆线后随机分为实验组、溶媒组和对照组3组,每组16只。实验组每天涂擦复方丹参膏2次,溶媒组每日涂擦溶媒膏二次,对照组不作任何处理。分别在术后0d、7d、15d、21d、30d、60d、90d测量上唇瘢痕的体积变化,并在7d、30d、60d时每组分别处死2只,90d后全部处死,取上唇瘢痕组织在光镜和电镜下观察组织病理学变化。组织学观察显示丹参可抑制成纤维细胞增殖,影响胶原蛋白合成,使胶原纤维重排和降解,从而减轻瘢痕增生。 相似文献
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27.
Masanori Hara M.D. Reiko Yoshida M.D. Susumu Inaba M.D. Akira Higuchi M.D. Yoshifumi Suzuki M.D. Toshio Okada M.D. Takakuni Tanizawa M.D. 《Pediatrics international》1991,33(3):335-344
The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings. 相似文献
28.
R S Nanra 《Nephrology, dialysis, transplantation》1992,7(5):384-390
Comprehensive renal function tests were performed in 84 patients with analgesic nephropathy, 33 glomerulonephritis patients matched for creatinine clearance, and 30 control subjects. A system of 1-day renal function tests including urine microscopy, creatinine clearance, phenolsulphonphthalein excretion, urine concentration and acidification, and electrolyte excretion, was used. Patients with analgesic nephropathy were found to have significant sterile pyuria and haematuria, even those with mild renal insufficiency, significantly reduced concentrating ability and a distal acidifying defect, and a tendency to impaired sodium conservation. These function defects are consistent with the primary lesion of renal papillary necrosis in analgesic nephropathy; the detection of these defects have implications in patient management. 相似文献
29.
以辣根过氧化物酶(PO)和抗-PO作为免疫沉淀中的抗原和抗体,用光电比色法,对78例小儿肾脏疾病血清补体对免疫沉淀的抑制作用(IIPC)进行了研究,并同时检测补体成分C3、C4。结果,正常对照IIPCOD值为0.505±0.085,急性肾小球肾炎(0.137±0.108)显著降低(P<0.001);慢性肾小球肾炎(0.470±0.053)改变不明显(P>0.05);肾病综合征(0.401±0.038)明显低下(P<0.05)。IIPC低下的发生率依次为急性肾小球肾炎(83%)、肾病综合征(43%)、慢性肾小球肾炎(32%)。表明小儿肾小球疾病时IIPC大多降低并与疾病的活动性有关。因此认为IIPC低下在肾脏病的发生和发展中起一定作用。 相似文献
30.
The effects of 10% dietary xylitol supplementation in ovariectomized rats were studied on the degradation of bone organic
and inorganic structures. The osseal concentrations of hydroxyproline, pyridinoline, and deoxypyridinoline were analyzed by
high-performance liquid chromatography. Bone resorption was measured in [3H]tetracycline-prelabeled rats by urinary excretion of 3H, and by the amount of 3H preserved in bone. Bone trabeculation was measured by a computer image analyzer from sections stained by the method of von
Kossa. The amount of collagen in bone organic fraction was lower in ovariectomized rats as compared with the sham-operated
controls. This most likely is partly a consequence of an increased resorption, and partly a consequence of a higher proportion
of immature periosteal bone in the ovariectomized animals, leading to a higher ratio of noncollagenous protein to collagen.
The number of pyridinium crosslinks was lower in proportion, indicating no selective changes in the structure of collagen.
Dietary xylitol significantly retarded the ovariectomy-associated decrease in the relative amount of collagen and the number
of its mature crosslinks. Ovariectomy doubled the excretion of 3H and caused a significant decrease in the amount of 3H preserved in bone; both these changes were significantly retarded by the 10% dietary xylitol supplementation. Ovariectomy
significantly decreased the volume of bone trabeculae, but this effect was also significantly inhibited by the xylitol supplementation
in the diet. In conclusion, these findings suggest a dietary xylitol-induced normalizing effect on the rate of bone turnover
in ovariectomized rats.
Received: 12 February 1996 / Accepted: 20 August 1996 相似文献