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101.
Patulin (PAT) is a mycotoxin produced in fruits, mainly in apples, by certain species of Penicillium, Aspergillus, and Byssochlamys. It has been shown that PAT is cytotoxic, genotoxic, and mutagenic in different cell types. Several studies incriminate the oxidative stress as a mechanism of PAT‐mediated toxicity. In this context, our aim was to investigate the protective role of Vitamin E (Vit E), an antioxidant agent, against PAT induced cytotoxicity and genotoxicity in cultured HepG2 cells. The obtained results showed that addition of Vit E in cells treated with PAT significantly reduce cell mortality induced by this toxin. In the same conditions, Vit E decreased the intracellular level of ROS, reduced PAT induced p53 expression, and reversed PAT induced DNA damage. In addition, Vit E prevented significantly the percentage of chromosome aberrations induced by PAT in HepG2 cells in a concentration dependant manner. These results suggest that Vit E, an exogenous antioxidant agent, plays an important role in defense against PAT‐induced cytotoxicity and genotoxicity, which confirms the involvement of oxidative stress in the induction of DNA damage by PAT in HepG2 cells. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.  相似文献   
102.
Infantile cutaneous hemangioma is a benign vascular tumour present at 10% of the infants. It forms part of the group of the vascular tumours in the classification of international society for vascular anomalies (ISSVA). Usual surgical attitude is abstention and surgery is proposed only in order to treat sequelae. But some particular situations require early surgery to avoid functional impairment, deformation or growth delay due to the lesion's development. Using our observations, we recall the epidemiology, the physiopathology, the clinical aspects, the particularities of the facial localizations and their treatments. In these localizations the time intervenes like a fourth dimension that is going to modify, to improve or to aggravate the prognosis. Treatment requires a strategy and precocious surgery. We insist on the fact that the dogma of the therapeutic abstention remained true for a majority of children with small size hemangioma and that a precocious surgery must be proposed for some localizations in the face.  相似文献   
103.
The aim of this study was to determine the appropriate tag sequence tagged site (STS) associated with azoospermia. We evaluated the incidence of Y chromosome microdeletions in Tunisian infertile male patients by polymerase chain reaction using 14 STSs in the azoospermia factor (AZF) region of Yq11. A logistic regression analysis was performed to test the association of STSs with semen quality. Haploview version 3.11 was used to identify the possible blocks of deletion involving a minimum number of STSs and that can be used to tag the deletion block in future analysis. Using the 14 STSs, 48% infertile patients (102 of 210) had microdeletions of Y chromosome but, following the European Academy of Andrology guidelines, only 16% of patients had microdeletions. A statistically significant difference was found with some STSs for azoospermia and oligozoospermia. A candidate combinaison composed of 4 STSs (RBMY-sy157-sy84-sy130) was associated with azoospermia in a Tunisian population. According to this study, this tag can be used in the screening of Y chromosome microdeletions before assisted reproduction treatment in a Tunisian population.  相似文献   
104.
Zearalenone (ZEN) is a potent estrogenic metabolite. Evidence of its cytotoxicity and genotoxicity has recently emerged from several reports. This study was conducted to evaluate the ability of cactus (Opuntia ficus-indica) cladodes to protect Balb/c mice against ZEN induced genotoxicity. To this end, the effect of a single dose of ZEN (40 mg/kg b.w.) alone and with extract of cactus cladodes (25, 50 and 100 mg/kg b.w.) was monitored by measuring: (i) micronuclei induction in bone marrow cells, (ii) chromosome aberrations mainly breaks and gaps in bone marrow cells also and finally and (iii) DNA fragmentation in liver and kidney.  相似文献   
105.
The purpose of the present study is to develop a novel method for the fabrication of transferable micropatterned cell sheets for tissue engineering. To achieve this development, microcontact printing of fibronectin on commercially available temperature-responsive dishes was employed. Primary rat hepatocytes were seeded on the dish surfaces printed with fibronectin. Under serum-free conditions, hepatocytes were attached onto fibronectin domains selectively. Then, a second cell type of endothelial cells was seeded in the presence of serum. Double fluorescent staining revealed that endothelial cells successfully adhered to the intervals of hepatocyte domains. Finally, all the cells were harvested as a single contiguous micropatterned cell sheet upon temperature-reduction. With a cell sheet manipulator having a gelatin layer for the support of harvested cell sheets, harvested micropatterned cell sheets were transferred to new dish surfaces. This technique would be useful for the fabrication of thick tissue constructs having a complex microarchitecture.  相似文献   
106.
We report the third case of endocarditis caused by the newly described micrococcal species Kytococcus schroeteri. A 49-year-old woman was admitted to the hospital with suspected prosthetic valve endocarditis. Five blood cultures and prosthetic valve cultures grew the same type of organism, initially identified as Micrococcus sp. Assignment to the genus Kytococcus was suggested by the arginine dihydrolase activity and resistance to oxacillin. After sequencing of the 16S rRNA genes, the isolate was recognized as K. schroeteri. The patient was treated first with vancomycin combined with gentamicin and later with pristinamycin and rifampin. Three cases of K. schroeteri endocarditis described within a short period of time might indicate a specific pathogenicity of this new species. The isolation of kytococci from normally sterile sites should not be overlooked.  相似文献   
107.
Epithelioid schwannomas mainly affect peripheral nerves and are frequently malignant. They are rarely encountered intracranially. Only five cases involving the eight nerve have been reported in the literature. We report the sixth case of epithelioid schwannoma of the acoustic nerve diagnosed in a 57 year-old woman operated for neurinoma of the right cerebellopontine angle. The patient was readmitted for local recurrence nine months later. Histologically, the tumour was composed of round or polygonal atypic cells associated with spindle cell areas. In our case, the local recurrence, nuclear pleomorphism and especially the high percentage of positive cells with p53 (80%) and Ki67 (30%) antibodies support the aggressive nature of the lesion.  相似文献   
108.
BACKGROUND: The Angiotensin-Converting Enzyme (ACE) is a candidate gene in the aetiology of several common diseases. The study of the haplotype structure of this gene is of interest in diagnosis and in pharmacogenomics. AIM: The study investigated the haplotype profile of single nucleotide polymorphisms (SNPs) within the ACE gene in the Tunisian population and compared it with other populations. SUBJECTS AND METHODS: Five SNPs (rs1800764, rs4291, rs4309, rs4331, rs4340) covering a region of 15.6 kb of the ACE gene were typed by PCR-digestion in a sample of 100 healthy subjects. RESULTS: All SNPs were polymorphic and in Hardy-Weinberg equilibrium. A total of 21 haplotypes were identified but only eight had a frequency of more than 1%. The four most common haplotypes had a cumulative frequency of 87.4%. The 'Yin-Yang' phenomenon (the two major haplotypes are complementary at all sites) was found. Linkage disequilibrium between all pairs of loci was highly significant (p<10-5). A simple and efficient statistical procedure was used to identify three important SNPs. CONCLUSION: The Tunisian population showed a different haplotype structure from the European one for the ACE gene and three important SNPs were identified. These will be very helpful in future association studies in the Tunisian and North African populations.  相似文献   
109.
The vagal maneuver is the first line of therapeutic available for patients with paroxysmal supraventricular tachycardia. It increases vagal tone and includes the traditional ocular compression, carotid sinus massage, and Valsalva maneuver.A 40-year-old man was admitted because of 180 beats/min regular narrow QRS-complex tachycardia. The physician in the emergency department had performed an ocular compression, and at its ending, the tachycardia degenerated into unstable hemodynamically high ventricular rate atrial fibrillation. It was reverted to sinus rhythm by electrical shock. The electrophysiologic study documented a latent posterolateral bypass tract, with an anterograde refractory period of 210 milliseconds, which was successfully ablated.  相似文献   
110.

Introduction

ST-segment resolution (STR) is a well-established and simple tool for assessing the efficacy of reperfusion therapy in myocardial infarction. An incomplete (<50%) STR is a recognized marker of failed thrombolysis and a suitable recruitment criterion for rescue angioplasty.

Objective

We sought to determine the predictive value of the total absence of STR after thrombolysis in rescue angioplasty (percutaneous coronary intervention [PCI]).

Methods

Eighty-one consecutive patients who underwent a rescue angioplasty for failed thrombolysis in our institution from 2001 to 2007 were included. Two groups of patients were defined according to their STR extent, 90 minutes after lysis: partial resolution group 1 (10%-50% STR) vs absence of resolution group 2 (<10% STR) and compared in terms of in-hospital and long-term outcomes.

Results

Patients of group 2 were more likely to experience hemodynamic deterioration (50% vs 24%; odds ratio [OR] = 3.17; P = .017), to have a Thrombolysis in Myocardial Infarction 0 flow on the culprit artery (62.3% vs 42%; OR = 2.24; P = .045), to have a multivessel disease (66.7% vs 40%; OR = 3; P = .018), and to die during index hospitalization (26.7% vs 6%; OR = 5.69; P = .013) despite statistically similar rates of PCI failure in both groups (10% vs 7%; P = .402) and similar post-PCI STR (72% ± 18.25% vs 75% ± 11.62%; P = .36). In multivariate analysis, total absence of STR proved to be an independent predictor of in-hospital mortality (HR = 7.02; P = .032; 95% confidence interval, 1.18-41.58). Long-term major adverse cardiac events occurred more frequently in group 2 (log rank, P = .004) and were (on the Cox regression model) independently predicted by total absence of STR (HR = 6.21; P = .023; 95% confidence interval, 1.28-29.1).

Conclusions

The STR assessment before rescue PCI proved to be a good and simple means to predict the short- and long-term prognosis in these patients.  相似文献   
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