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31.
The effect of Phagnalon rupestre MeOH extract on dinitrofluorobenzene- and sheep red blood cells-induced hypersensitivity was investigated. Eight compounds were identified: three dimethylallyl-hydroquinone glucosides (1 - 3), 3,5- and 4,5-di-O-caffeoylquinic acid methyl esters (4 and 5), their free carboxyl analogues (6 and 7), and luteolin 7-O-beta-glucoside (8). All were tested for dinitrofluorobenzene-induced contact hypersensitivity inhibitory activity. Flavonoid 8 was the most active (49 % and 79 % inhibition at 24 and 96 h, respectively). The hydroquinones 1, 2 and 3 were effective at 96 h after challenge (62 %, 73 % and 60 % inhibition, respectively), while some of the dicaffeoylquinic derivatives (4 and 7) produced slightly lower reduction of the inflammatory reaction.  相似文献   
32.
Experimental severe secondary hyperparathyroidism (HPT) is reversed within 1 wk after reversal of uremia by an isogenic kidney transplantation (KT) in the uremic rats. Abnormal parathyroid hormone (PTH) secretion in uremia is related to downregulation of CaR and vitamin D receptor (VDR) in the parathyroid glands (PG). The aim of this investigation was to examine the expression of CaR and VDR genes after reversal of uremia and HPT in KT rats. 5/6 nephrectomized rats were kept on a normal or high-phosphorus (hP) diet for 8 wk to induce severe HPT (n = 8 in each group). In another group of seven uremic hP rats, uremia was reversed by an isogenic KT and PG were harvested within 1 wk posttransplant. Plasma urea, creatinine, total calcium, phosphorus, and PTH levels were measured. Parathyroid CaR and VDR mRNA were measured by quantitative PCR. Uremic hP rats had significantly elevated levels of creatinine, urea, and phosphorus (P < 0.001) and developed significant hypocalcemia (plasma calcium 1.83 +/- 0.2 mmol/L; P < 0.001) compared with normal control rats. After KT, the levels were normalized from day 3 to 7: creatinine from 0.117 +/- 0.016 to 0.050 +/- 0.002 mmol/L; urea from 23 +/- 4 to 7 +/- 0.3 mmol/L; phosphorus from 3.9 +/- 0.6 to 1.5 +/- 0.06 mmol/L; calcium from 1.8 +/- 0.2 to 2.5 +/- 0.02 mmol/L. Plasma PTH levels fell from 849 +/- 224 to a normal level of 38 +/- 9 pg/ml (P < 0.01). In uremic rats on a standard diet, CaR mRNA was similar to that of normal control rats, whereas VDR mRNA was significantly decreased. In uremic rats kept on hP diet, CaR mRNA was significantly decreased to 26 +/- 7% of control rats (P = 0.01) and VDR mRNA reduced to 36 +/- 11% (P < 0.01). In KT, previously hP uremic rats, both CaR mRNA and VDR mRNA remained severely reduced (CaR, 39 +/- 7%; VDR, 9 +/- 3%; P < 0.01) compared with normal rats. In conclusion, circulating plasma PTH levels normalized rapidly after KT, despite persisting downregulation of CaR and VDR gene expression. This indicates that upregulation of CaR mRNA and VDR mRNA is not necessary to induce the rapid normalization of PTH secretion from hyperplastic parathyroid glands.  相似文献   
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The purpose of this study was to examine the role of chromosomal recombination in mediating p53 loss in benzene-induced thymic lymphomas in C57BL/6-Trp53 haploinsufficient (N5) mice (p53+/- mice). We characterized loss of heterozygosity (LOH) on chromosome 11 using seven microsatellite markers in 27 benzene-induced and 6 spontaneous thymic lymphomas. Eleven patterns of LOH were found between the induced and spontaneous tumors, with only one pattern being in common between the tumor groups. Nearly 90% (24 of 27) of benzene-induced tumors exhibited loss of the functional p53 allele locus, and 83% (20 of 24) of these tumors retained two copies of the disrupted p53 allele. The results indicate that benzene induces a high frequency of LOH on chromosome 11 in p53+/- mice, likely mediated by aberrant chromosomal recombination.  相似文献   
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36.
Objective: To present our experience with 14 cases of fetal intracranial hemorrhage (ICH).

Methods: Cases of fetal ICH detected in our institution between 2005 and 2016 by ultrasonography. Maternal characteristics, ultrasound and MRI findings, and postnatal outcome were noted.

Results: Twelve cases (86.7%) were identified during a third trimester routine scan at a median gestational age of 30.6 weeks. The ICH was classified as Grade 2 in two cases, Grade 3 in three cases, and Grade 4 in nine cases. Nine cases were bilateral and five were unilateral (four left/one right). The 11 MRI available confirmed grade and location and, in six cases (54.5%), added new findings. There were six terminations of pregnancy, one intrauterine fetal death and seven babies born alive. These were followed up for 28 months (range 3–96). Some grade of neurologic impairment was observed in five children (71.4%, one Grade 3/four Grade 4), mainly mild to moderate motor sequelae.

Conclusion: Diagnosis of fetal ICH is amenable to antenatal US. Most of the cases identified are of high grade and usually detected during the third trimester. MRI is a valuable complementary tool in evaluating ICH. Conversely to that previously reported, postnatal survival is high but it entails the risk of adverse neurologic outcome in most neonates.  相似文献   

37.
Painful sensory neuropathies consist of a wide range of neuropathies that can involve large as well as small nerve fibres. Even if most cases remain of unknown cause, some of them may be associated with an underlying disorder such as diabetes, HIV, infections, amyloidosis, and Sjogren's syndrome. Since in some cases an autoimmune mechanism has been postulated, we investigated a panel of circulating autoantibodies including anti‐gliadin (AGA), anti‐endomysium (EmA), anti‐transglutaminase (tTGA) and anti‐nuclear (ANA) antibodies in the sera of patients with unexplained painful sensory neuropathies in order to identify other potentially treatable disorders. We tested the sera of 10 patients (4M; 6F) previously investigated for other causes of neuropathies, including anti‐nerve, onconeural, anti‐extractable nuclear, anti‐neutrophil cytoplasmic, anti‐thyroglobulin (TgA) and anti‐peroxidase (TPOA) antibodies. We found the presence of AGA positivity in 4 patients (40%), ANA in 7 (70%) and AGA + ANA in 4 (40%), two of whom were negative for celiac disease by gastrointestinal biopsy. None of the patients had EmA positivity. Three (30%) had TgA and TPOA and none had anti‐nerve or onconeural antibodies. Whether the presence of circulating autoantibodies in patients with unexplained painful neuropathy reflects an autoimmune involvement which may be amenable to immune therapy and not only to symptomatic treatment remains to be established.  相似文献   
38.
Organophosphorous pesticides (OPs) are suspected of altering reproductive function by reducing brain acetylcholinesterase activity and monoamine levels, thus impairing hypothalamic and/or pituitary endocrine functions and gonadal processes. Our objective was to evaluate in a longitudinal study the association between OP exposure and serum levels of pituitary and sex hormones. Urinary OP metabolite levels were measured by gas-liquid chromatography, and serum pituitary and sex hormone levels by enzymatic immunoassay and radioimmunoassay in 64 men. A total of 147 urine and blood samples were analyzed for each parameter. More than 80% of the participants had at least one OP metabolite in their urine samples. The most frequent metabolite found was diethylthiophosphate (DETP; 55%), followed by diethylphosphate (DEP; 46%), dimethylthiophosphate (DMTP; 32%), and dimethyldithiophosphate (DMDTP; 31%). However, the metabolites detected at higher concentrations were DMTP, DEP, DMDTP, and dimethylphosphate. There was a high proportion of individuals with follicle-stimulating hormone (FSH) concentrations outside the range of normality (48%). The average FSH serum levels were higher during the heavy pesticide spraying season. However, a multivariate analysis of data collected in all periods showed that serum FSH levels were negatively associated with urinary concentrations of both DMTP and DMDTP, whereas luteinizing hormone (LH) was negatively associated with DMTP. We observed no significant associations between estradiol or testosterone serum levels with OP metabolites. The hormonal disruption in agricultural workers presented here, together with results from experimental animal studies, suggests that OP exposure disrupts the hypothalamic-pituitary endocrine function and also indicates that FSH and LH are the hormones most affected.  相似文献   
39.
The rostral migratory stream is one of the few regions of the adult mammalian central nervous system in which cellular migration and proliferation have been described. Most rostral migratory stream cells divide rapidly and hence different proliferation markers have been employed to identify them. Nitrogen base substitutes, such as tritiated thymidine or 5-bromo-2'-deoxyuridine (BrdU), together with endogenous molecules, such as Proliferating Cell Nuclear Antigen (PCNA), are the cell cycle markers most widely employed. Protocols for BrdU and PCNA localization are both plentiful and diverse, but to date no optimized protocol for obtaining trustworthy double staining of both markers has been described. In this work, we propose optimized protocols for achieving both single staining and the joint detection of BrdU and PCNA in the rodent brain using double-immunofluorescence procedures. The double labeling described allows the discrimination of different cell cycle stages in migratory cells from the mouse brain.  相似文献   
40.
BACKGROUND: Bleeding indices are used as a screen for periodontal disease activity, a measure of disease prevalence, and a measure of effectiveness in clinical trials. Bleeding on probing (BOP) is widely interpreted as a sign of disease activity whereas its absence is interpreted as both a sign and predictor of health. Aspirin use has become increasingly common in the prevention of cerebrovascular and cardiovascular diseases. Because of its anti-platelet activity, aspirin is a non-disease factor that has the potential to affect the appearance of BOP. The hypothesis being tested is that short-term aspirin use in doses of 81 mg and 325 mg will increase the number of bleeding sites in a population with gingivitis. METHODS: Fifty-four subjects were screened initially, those subjects with 20% to 30% whole mouth BOP were randomly assigned to one of three arms: placebo group, 81 mg aspirin group, or 325 mg aspirin group. Before and after exposure to the respective regimens, clinical parameters were measured on all the teeth: the plaque index was recorded at four sites per tooth, and probing depth and BOP were evaluated at six sites per tooth using an automated pressure-sensitive probe. RESULTS: The data obtained in this clinical trial were analyzed utilizing a linear regression analysis to control for confounding variables. The primary measure of interest was BOP in patients clinically demonstrating naturally occurring gingivitis. The results of this study indicate that while controlling for age, gender, and plaque, "low dose" 81 mg and "regular dose" 325 mg of aspirin demonstrated a statistically significant 5.30 (P = 0.001) and 4.13 (P = 0.010) increase from baseline, respectively, in percent BOP. CONCLUSION: Failure to consider the effects of aspirin on BOP could impair proper diagnosis and treatment planning for clinicians and introduce a significant confounding variable in research situations.  相似文献   
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