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101.
Dysplastic changes in erythroid precursors occur not only in patients with hematologic diseases, but also those with other diseases. Here, we report on a patient that presented with dysplastic changes in erythroid precursors due to lead poisoning from the intake of Chinese folk remedies.  相似文献   
102.
Anxiety is one of the most common mental disorders sharing extreme or pathological anxiety states as the primary disturbance in mood or emotional tone, with increased fear and exaggerated acute stress responses. Medicinal plants are very variable, but some of them are used as a spice such as curcumin (Curcuma longa). Curcumin shows a wide range of pharmacological potentialities, however, little is known about its anxiolytic properties. The aim of our study was to assess the anti-anxiety potential of curcumin extract against experimental lead induced-anxiety in rats. Experiments were carried out on male Wistar rats intoxicated acutely with an intraperitoneal injection of Pb (25 mg/kg B.W.) and/or concomitantly with administration of curcumin (30 mg/kg B.W.) for 3 days. Using immunohistochemistry and anxiety assessment tests (dark light box and elevated plus maze), we evaluated, respectively, the expression of serotonin (5HT) in the dorsal raphe nucleus (DRN) and the anxiety state in our animals. Our results showed, for the first time, a noticeable anxiolytic effect of curcumin against lead induced anxiety in rats and this may possibly result from modulation of central neuronal monoaminergic neurotransmission, especially serotonin, which has shown a significant reduction of the immunoreactivity within the DRN.  相似文献   
103.
目的初步探讨低水平铅暴露对女性血清性激素及月经周期的影响。方法对铅暴露女性269人及对照组女性348人的一般情况、生殖结局进行回顾性队列研究,并测血铅及用放射免疫法测定孕酮(P)、雌二醇(E2)、催乳素(PRL)、卵泡刺激素(FSH)、黄体生成素(LH)性激素水平。结果暴露组女性月经紊乱明显高于对照组(P〈0.01),且早产率、自然流产率亦高于对照组,差异有统计学意义(P〈0.01);暴露组血清性激素水平孕酮(P)、雌二醇(E2)降低,促卵泡素、促黄体生成素升高。结论说明长期低浓度铅暴露干扰下丘脑一垂体~卵巢轴正常的内分泌调节功能,可引起女性月经失调、影响内分泌激素水平。  相似文献   
104.
105.
BackgroundEssential tremor (ET) is one of the most common movement disorders. Normally ET affects the distal upper extremities, but it can also be accompanied by midline symptoms. Ventralis intermedius (VIM) thalamic deep brain stimulation (DBS) has been shown to be effective in reducing hand tremor, but its effects on head tremor have been inconsistent.MethodsTwenty-nine DBS patients with a diagnosis of ET met inclusion criteria. All implantations targeted VIM. The factors examined included age, gender, disease duration, presence or absence of head tremor, handedness, and the Fahn-Tolosa-Marin rating scale (TRS). This analysis specifically focused on TRS head tremor sub-scores at baseline, 6 months and 12 months post-DBS. Additionally, DBS lead entry angles were examined.ResultsTwenty-three ET patients underwent unilateral DBS and six underwent staged bilateral DBS. At both 6 and 12 months following DBS, stimulation resulted in diminished head tremor (ON vs OFF; p < 0.0001). The most important predictor of head tremor suppression was the entry angle of the DBS lead in the sagittal projection relative to the AC–PC axial plane (AC–PC angle). Head tremor reduction was greater among more vertical AC–PC angles.ConclusionA more vertical AC–PC angle of the DBS lead trajectory was associated with improved head tremor suppression. Further studies will be necessary to confirm this potentially important finding.  相似文献   
106.
107.
The secretory activity of subcommissural organ cells is controlled by various extrinsic and intrinsic factors. Lead has been recognised as a neurotoxic heavy metal, since it induces morphological and functional abnormalities in the brain. In this work, we examined the effect of lead exposure on the subcommissural organ (SCO), a brain gland known by its secretion of Reissner's fiber (RF) in cerebro-spinal fluid. Glycoprotein secretion and serotonin (5HT) innervation of the SCO was examined after acute and chronic lead exposures in the sub-desert rodent Meriones shawi. Lead exposures were achieved by, respectively, intra-peritoneal injection of 25 mg/kg body weight of lead acetate for 3 days and 0.5% of lead acetate in the drinking water over 4 months until adult age. 5HT and RF immunolabeling in the SCO revealed several serotoninergic fibers reaching the SCO and abundant secretory material. An increase in both 5HT innervation and secretory material of the SCO was recorded after both acute and chronic lead exposure. These results show that lead exposure affects the serotonergic innervation of the SCO. Moreover, the enhancement of SCO secretion suggests a role of this gland in neuroprotection and lead detoxification of the brain in Meriones shawi.  相似文献   
108.

Background

Lead acetate (Led) and mercury chloride (Mer) represent important ecological and public health concerns due to their hazardous toxicities. Naturally found products play a vital role in chemopreventive agent innovation. The current study aimed to assess the modifying effect of garlic (Gar) and/or vitamin E (Vit E) against the half-maximal inhibitory concentration (IC50) Led and/or Mer-induced cytotoxic, genotoxic and apoptotic effects.

Methods

Human lung cells (WI-38) were pretreated with Gar and/or Vit E for 24 h and then treated with Led and/or Mer either alone or with their combination for 24 h. Cytotoxicity of Led and Mer and the viability of Gar and Vit E were assessed using MTT assay. The alkaline comet assay was used to assess DNA damage, whereas QRT-PCR was performed to evaluate p53, Bax, and Bcl2 mRNA-expression.

Results

The results of this study showed that IC50 of Led was (732.72 μg/mL) and for Mer was (885.83 μg/mL), while cell viability effective dose for Gar was (300 μg/mL) and for Vit E was (26,800 μg/mL). Treating cells with the IC50-concentration of Led or Mer or their combination using half IC50 of both of them induced severe DNA-damage. Bax-expression was increased, while p53 and Bcl2-expressions were decreased. Pretreatment of cells with Gar and/or Vit E ameliorated the previous alternations.

Conclusions

Led and Mer can induce oxidative stress and change the expressions of apoptosis-related proteins in WI-38 cells. Gar and Vit E may be promising protective candidate agent against the toxic effect of heavy metals.  相似文献   
109.
To assess the association between birth weight and maternal blood lead (BPb) levels, 386 pregnant women and their newborn offspring were surveyed. Mean ± SD (range) maternal BPb concentrations were 0.98 ± 0.55 (0.10–3.99), 0.92 ± 0.63 [<0.09 (limit of quantification)–3.96], and 0.99 ± 0.66 (<0.09–3.96) μg/dl at 12, 25 and 36 weeks’ gestation, respectively. Mean ± SD (range) gestational age at delivery was 38.9 ± 1.3 (35–41) weeks. In male newborns, a significant correlation between birth weight and logBPb at 12 weeks’ gestation was observed (Spearman's rank correlation coefficient = −0.145, p < 0.05). Multiple regression analysis indicated that birth weight was significantly inversely associated with logBPb at 12 weeks’ gestation, controlling for possible confounding variables. These results suggest that low-level exposure to lead in early gestation could be a risk factor for reduced birth weight in male offspring.  相似文献   
110.
Multiple trace elements have estrogen receptor activity, but the association of these elements with uterine leiomyoma has not been defined. A cohort of 473 women aged 18–44 undergoing surgery for benign gynecologic indications provided whole blood and urine specimens for trace element analysis, which was performed by inductively coupled plasma mass spectrometry. Twenty elements were analyzed in blood and 3 in urine. The surgeon documented whether fibroids were present. Geometric mean concentrations were compared between women with and without fibroids, and logistic regression models were generated to assess the impact of the concentration of each trace element on the odds of fibroids. In multivariate regressions, odds of a fibroid diagnosis were higher with increased whole blood cadmium (AOR 1.44, 95% CI 1.02, 2.04) and lead (AOR 1.31 95% CI 1.02, 1.69), and urine cobalt (AOR 1.31, 95% CI 1.02, 1.70). Urinary cadmium and lead were not related to fibroid diagnosis. Increased exposure to trace elements may contribute to fibroid growth, and fibroids may serve as a reservoir for these elements. Differences between urinary and whole blood findings merit further investigation, as urinary cadmium has been considered a superior marker of exposure.  相似文献   
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