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Sadanandavalli Retnaswami Chandra Pawan Raj Thomas Gregor Issac 《Indian journal of dermatology》2015,60(3):290-292
Neurodegeneration with brain iron accumulation (NBIA) is the term applied to a heterogeneous group of disorders resulting in iron deposition in the basal ganglia. Well-known phenotypic features are progressive regression with extra pyramidal involvement and a variable course. A 10-year-old child born to consanguineous parents presented with progressive generalized opisthotonic dystonia, retrocollis, oromandibular dyskinesias, apraxia for swallowing, optic atrophy and severe self-mutilation of lips. MR imaging showed brain iron accumulation. Other causes of self-mutilation were excluded. Early infantile onset, ophisthotonic dystonia with oromandibular dyskinesias and characteristic MR images are suggestive of NBIA. There is only one case reported in the literature of self-mutilation in this condition. 相似文献
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Ramya Deepthi Vinnakota Allan S. Brett 《The American journal of the medical sciences》2019,357(2):160-163
Iron deficiency anemia is often listed among potential adverse effects of gastric acid-suppressive medications, given that gastric acidity promotes intestinal absorption of nonheme iron. Additionally, the antacid calcium carbonate can inhibit iron absorption. However, there is little direct clinical evidence that proton-pump inhibitors, histamine-2 receptor antagonists, or calcium carbonate cause iron deficiency anemia. Most case reports have had substantial limitations (e.g., minimal follow-up and presence of other causes of iron deficiency), and retrospective cohort studies have lacked sufficient patient-specific detail to make strong causal inferences. We present 2 cases—both with detailed, prospective 10-year follow-up—in which combinations of proton-pump inhibitors, histamine-2 receptor antagonists and calcium carbonate were clearly associated with development of iron deficiency anemia. Overt iron-deficiency anemia is probably uncommon in patients who use acid-modifying medications and who have no other conditions that predispose to iron deficiency. Nevertheless, clinicians should be aware of this potential complication, given widespread use of these agents. 相似文献
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Moussa Ndong Machiko Kazami Tsukasa Suzuki Mariko Uehara Shin-ichi Katsumata Hirohumi Inoue Ken-Ichi Kobayashi Tadahiro Tadokoro Kazuharu Suzuki Yuji Yamamoto 《Nutrition Research》2009,29(9):640-647
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity. 相似文献
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铁缺乏时淋巴细胞增殖反应改变的实验研究 总被引:1,自引:0,他引:1
本研究采用体外细胞培养,3H-Tdr掺入,原子吸收光谱分析等技术方法,观察了低浓度Fe-cit时淋巴细胞内铁浓度变化及经ConA、PHA诱导的细胞增殖反应能力改变,结果显示:铁缺乏时(第2、3、4组)SI降低,与正常组(第1组)比较相差非常显著(P<0.01),SI与细胞内铁浓度的变化呈显著正相关(P<0.05,r1=0.9466,r2=0.9339),说明铁缺乏时淋巴细胞增殖反应能力受抑。 相似文献
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为了了解吉林省长白县山区所产卫矛科雷公藤属植物黑蔓的药理作用,扩大它的药用部位和应用范围,我们从无机元素与中药药效有密切关系的角度出发,实验测出黑蔓含有Ba、Si、Cu、Fe、Zn、Sn、Co、Mn、Mg、Ca、Se等无机元素,本文重点对其中人体必需的微量元素Cu、Fe、Zn、Se作了定量分析。 相似文献
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目的 :了解昆明城区及大理农村 7月~ 7岁儿童目前的铁缺乏水平 ,进一步展开对儿童铁缺乏症的防治 ,降低儿童营养性缺铁性贫血的患病率 .方法 :采用抽样调查的方法对两地 7月~ 7岁儿童共 96 9名进行血清铁蛋白 (SF)、锌原卟啉 (ZPP)、血红蛋白 (Hb)实验室检查 .结果 :7月~ 7岁儿童的总铁缺乏检出率为 2 5 1% ,铁减少检出率为 19 0 % ,贫血患病率为 6 1% ;男女童患病率在 1岁以前差别较大 ,1岁以后差别不明显 ;各年龄组患病率以 7月~ 1岁组最高 ;早产儿、低出生体重儿童患病率相对较高 ;铁缺乏的儿童营养不良的患病率高于正常儿童 .结论 :儿童缺铁性贫血仍要引起重视 .在防治中要抓重点人群 ,除改变膳食结构和饮食习惯 ,对目标人群要适当补充铁剂预防 相似文献
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Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways. 相似文献