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This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells.  相似文献   
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An assessment of burn depth is a key step in guiding the treatment of patients who have sustained thermal injuries. Polarization-sensitive optical coherence tomography (PS-OCT) might eventually provide the physician with a quantitative estimate of actual burn depth. Burns of various depths were induced by contacting rat skin with a brass rod preheated to 75 degrees C for 5, 15, or 30 s. Thermal injury denatured the collagen in the skin, and PS-OCT imaged the resulting reduction of birefringence through the depth-resolved changes in the polarization state of light propagated and reflected from the sample. Stokes vectors were calculated for each point in the PS-OCT images and the reduction in the rate of phase retardation between two orthogonal polarizations of light (deg/microm) was found to show a consistent trend with burn exposure time. PS-OCT is a noninvasive technique with potential to give the physician the information needed to formulate an optimal treatment plan for burn patients.  相似文献   
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Abstract: Increased expression of P‐glycoprotein encoded by the mdr‐1 gene is a well‐characterised mechanism for resistance to cancer chemotherapeutic drugs in cell lines. However, the P‐glycoprotein expression after removal of the selection pressure has not fully been elucidated. The stability of P‐glycoprotein expression in the presence (+) and absence (?) of vincristine (30 or 150 nM) was studied in multidrug resistant K562 cell lines (VCR30+, VCR150+, VCR30? and VCR150?) for 11 months. The P‐glycoprotein protein and mdr‐1 mRNA levels were determined at regular intervals using flow cytometry and real‐time PCR, respectively. Chemosensitivity to a panel of antineoplastic drugs was measured using an MTT assay. The presence of vincristine (VCR30+ and VCR150+) resulted in high and stable levels of P‐glycoprotein and mdr‐1 mRNA during the whole period compared to wild type. As for the VCR30? and VCR150? subcultures, the expressions of P‐glycoprotein and mdr‐1 mRNA were stable for five months, and then the levels decreased rapidly. Concomitantly, the sensitivity to drugs known as P‐glycoprotein substrates was restored. In conclusion, resistant cells growing in the presence of the inducing drug have a stable P‐glycoprotein expression and resistance level, but removing the inducing drug may result in a sudden and rapid lowering of P‐glycoprotein and mdr‐1 mRNA levels as long as five months after drug withdrawal.  相似文献   
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FH is a genetic disorder characterized by an increase in serum LDL and total cholesterol values. The afflicted patients are at increased risk of premature atherosclerosis and myocardial infarction. Different treatment modalities are present, including pharmacological agents and surgical procedures. The most effective method of therapy in refractive cases is liver transplantation. Herein, we report our experience on 36 cases of patients with FH undergoing liver transplantation in our center, the main referral center of liver transplantation in Iran. The clinical findings, hospital courses, post‐operative complications, and patient follow‐up are also described.  相似文献   
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AIDS and Behavior - Sexual transmission accounts for the majority of new HIV infections in Iran. More than 80% of HIV-positive persons are sexually active, and nearly 68% reported never using a...  相似文献   
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Do P  Randhawa I  Chin T  Parsapour K  Nussbaum E 《Lung》2012,190(4):463-468

Purpose

Plastic bronchitis is the occlusion of the major bronchial airways by a firm, gelatinous mucoid cast. It is a rare condition, which while classically described in asthma and sickle cell disease has greater mortality in patients with congenital heart disease. The management of this disease is obscure given the lack of clinical data regarding treatment therapies.

Methods

We describe a case of an 11-year-old female status after Fontan surgery who presented with respiratory distress secondary to atelectasis of the right lung.

Results

A bronchoscopy was performed demonstrating an obstructing bronchial cast with successful extraction. The plastic bronchitis continued to recur and she was placed on multiple inhaled mucolytics as well as inhaled tissue plasminogen activator with temporary resolution. Further evaluation of the etiology of her casts revealed that she had elevated pulmonary arterial pressures. Repeated bronchoscopic removal of the casts was utilized as well as continuation of the aggressive airway clearance. Ultimately fenestration of her Fontan was performed along with treatment of pulmonary vasodilators sildenafil and bosentan. Although there was improvement of the cast formation, her airway clearance could only be weaned to four times a day therapy with which she was discharged home after a 3-month hospitalization. She continues to remain on this therapy and has not required hospitalization since the initial incident over 1?year ago.

Conclusions

Plastic bronchitis in a patient with Fontan physiology presents a treatment dilemma that may require comprehensive therapy in severe cases such as described.  相似文献   
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BACKGROUND: Leukocyte telomere length, a putative marker of ageing, is a highly variable and heritable complex trait. In order to determine the possible underlying genetic variants for leukocyte telomere length variation, we conducted an association study of leukocyte telomere length and two candidate genes for ageing-related traits, TGFB1 and KLOTHO, in a female Caucasian dizygotic twin population. METHODS AND MATERIALS: Terminal restriction fragment (TRF) length, an index of telomere length, was measured using Southern Blotting. Six and four single nucleotide polymorphisms (SNP) were genotyped in TGFB1 and KLOTHO gene, respectively, and tested for association. When there is strong LD between SNPs (r(2) > 0.5), haplotypic association was investigated using haplotype trend regression approach. RESULTS: All SNPs were in Hardy-Weinberg equilibrium (p > 0.05). No significant association was detected for individual SNPs (p > 0.101), or two-locus haplotypes (p = 0.7497) with TRF variation. CONCLUSION: We failed to find any significant association between leukocyte telomere length and 10 SNPs in two ageing-related candidate genes, TGFB1 and KLOTHO. This result suggests that while we could not exclude minor effects, none of 10 SNPs in these two candidate genes showed significant association with the variation of leukocyte telomere length in our cohort. But as it is unclear whether telomere length dynamics is the cause or the effect of the ageing process, it is still possible the genes are associated with ageing via alternate mechanisms.  相似文献   
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