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1.
Rituximab is a chimeric monoclonal antibody that recognizes the CD20 antigen and is used to treat B-cell non-Hodgkin lymphoma (B-NHL). Few studies have been published examining the use of antibody panels to evaluate B-NHL treated with rituximab. The authors performed a retrospective analysis of immunophenotypic changes and clinical outcome in 18 patients with B-NHL following rituximab therapy. The intensity of CD20 expression was evaluated by flow cytometry and/or immunohistochemistry, before and after rituximab therapy; the latter samples were taken 5 to 12 months after initiating rituximab therapy (median 7 months). Nine of the 18 patients (50%) achieved complete or partial clinical remission and did not have morphologic evidence of lymphoma in the post-therapy samples. The other nine patients (50%) had persistent disease. Two patterns of CD20 expression were noted in the post-therapy samples: unchanged expression of CD20 in neoplastic cells (4/9 cases) and loss of or a significant decrease in detected CD20 expression in neoplastic cells (5/9 cases). These results show that in many cases of B-NHL persisting after rituximab therapy, CD20 expression decreases or is lost, raising the possibility of deletion or expression modulation of the CD20 gene in neoplastic cells. This study also underscores the importance of using a panel of antibodies to evaluate rituximab-treated B-NHL.  相似文献   
2.
Neurosurgical Review - Treatment options for hydrocephalus include endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS). Some ambiguity remains regarding indications, safety,...  相似文献   
3.
Natural polyphenols are widely reported to have a large range of pharmacological properties, especially antioxidant activities and free radical scavenging capacities. In this study, we investigate the effects of naringin, chlorogenic acid, and quercetin mixtures (NCQ) on renal fibrosis in streptozotocin (STZ)-induced diabetic aged rats and its underlying mechanisms for ten consecutive weeks. The oxidative defense system in the kidneys of treated rats was found to be improved. Several biomarkers were investigated including the blood urea nitrogen, creatinine, and uric acid. Moreover, antioxidant parameters were evaluated and we found that superoxide dismutase, catalase, glutathione peroxidase, Na+-K+-ATPase activities, the nitric oxide production, the protein carbonyl, the advanced oxidation protein products, lipid peroxidation, and reduced glutathione levels were all significantly balanced and close to control values. In addition, NCQ restored renal injuries and fibrosis as assessed by histological method and molecular biology investigation of the matrix metalloproteinase, the transforming growth factor-beta TGF-β, the tumor necrosis factor TNFα, and p53 expression. Our study proposes the NCQ combination as potential plant-derived bioactive compounds to prevent diabetic nephropathy.  相似文献   
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5.

Background

Comprehensive preoperative appraisal of potential living renal donors is the key for selecting a proper donor and a suitable kidney.

Objective

To prospectively assess the diagnostic value of 16-slice multidetector computed tomography (MDCT) in preoperative appraisal of vascular anatomy in potential living renal donors.

Materials and methods

Preoperative angiography using a 16-slice MDCT scanner was performed in 68 consecutive potential living renal donors. The MDCT angiography included unenhanced and contrast-enhanced multiphasic scans. The MDCT images were reviewed for the number and branching pattern of the renal arteries and for the number and presence of major or minor variants of the renal veins. The results were compared with the actual anatomy at the open donor nephrectomy as the diagnostic standard of reference.

Results

The sensitivity and the specificity of MDCT angiography for the detection of various anatomic variants of renal arteries as well as renal venous anomalies were 100%. The anatomic variants of renal arteries included accessory arteries (n = 7) and early arterial branching (n = 10). Whereas, the detected venous anomalies were of major category of the circumaortic left renal vein anomaly (n = 2). No minor renal venous anomaly was identified in any subject.

Conclusion

16-Slice MDCT angiography is highly accurate for preoperative assessment of diverse anomalies of the renal vascular anatomy in potential living renal donors; in consequence, it markedly affects the surgical planning.  相似文献   
6.

Aim of the work

To detect interictal changes of the metabolic concentration ratios in the thalami of patients with migraine without aura by using 1H-MRS.

Materials and methods

Twenty-two patients of migraine without aura were enrolled in this study in addition to 10 healthy controls. Patients were further divided into 2 subgroups; 12 with left-sided migraine and 10 with right-sided migraine. Patients were imaged interictally with multivoxel 1H-MRS for measuring the NAA/Cho, NAA/Cr, Cho/Cr, MI/NAA and Lac/NAA ratios in both thalami.

Results

Each of the mean NAA/Cho and NAA/Cr ratios was significantly decreased in patients compared to controls, and also on the contralateral side compared to the side of migraine in each subgroup of patients. In contrary, no significant difference was found in Cho/Cr, MI/NAA and Lac/NAA ratios between patients and controls, as well as on comparing both sides in each subgroup of patients. Furthermore, increased duration of illness and frequency of attacks were significantly associated with decreased NAA/Cho and NAA/Cr ratios as well as increased MI/NAA and Lac/NAA ratios.

Conclusion

Migraine without aura is associated with thalamic interictal changes in the mean metabolite concentration ratios, detected with multivoxel 1H-MRS.  相似文献   
7.
BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making.  相似文献   
8.
9.
Intramyocardial dissecting hematoma (IDH) is a rare complication of myocardial infarction (MI). It can affect the left ventricular free wall, the right ventricle, or the interventricular septum. We report a case of a 58-year-old man with an IDH following an acute anterior wall myocardial infarction detected by echocardiography and confirmed by Cardiac magnetic resonance (CMR).  相似文献   
10.
Acanthamoeba castellanii is a protozoan parasite that may cause sight-threatening keratitis in some individuals. Its eradication is difficult because the trophozoites encyst making organisms highly resistant to anti-amoebic drugs. To test new anti-Acanthamoeba agents, usually having low water solubility, organic solvents and surfactant agents should be used. Therefore, the lethal effect of different concentrations of the solvents acetone, methanol, ethanol, and DMSO and surfactant agents Tween 20, Tween 80, and Triton X-100 was tested. The minimal inhibitory concentrations (MIC) were determined against Acanthamoeba cysts. Results of the present study showed that the MIC for ethanol, methanol, acetone and DMSO was 25, 12.5, 12.5, and 10 %, respectively and for Tween 20, Tween 80, and Triton X-100 was 0.25, 0.06, and 0.03 %, respectively. There was no significant inhibitory effect on the multiplication of Acanthamoeba cysts as compared to parasite control when using the concentrations 3.12 % for ethanol, 1.6 % for methanol and acetone, 1.25 % for DMSO, and 0.016 % for Tween 20. On the other hand, both Tween 80 and Triton X-100 showed highly significant difference in comparison to parasite control almost among all the range of concentrations used in this study, and both showed lethal effect of 19 and 27.2 %, respectively at their least concentration.  相似文献   
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