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121.

Objectives

The aim of the current study was to assess the utility of F-18-fluoro-2-deoxy-d-glucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) in assessing bone marrow involvement (BMI) compared to bone marrow biopsy (BMB) in initial staging of Hodgkin’s lymphoma (HL) in pediatric patients.

Methods

Data of 38 pediatric patients (mean age 9.8 years, range 3–18 years) with HL were analyzed for the involvement of bone marrow. All patients underwent non-contrast F-18 FDG PET/CT study. BMB was done in 31 patients from the bilateral iliac crests. Scans were interpreted by two nuclear medicine physicians blinded to the details of BMB.

Results

Of the 31 patients who underwent BMB, 5 patients had lymphomatous involvement on BMB. PET/CT was positive in four of these five patients. In 26 patients negative on BMB, PET was negative in 23 patients and positive in 3 patients for BMI. The sensitivity and negative predictive value of F-18 FDG PET/CT was 87.5 and 96 %, respectively, for BMI.

Conclusions

F-18 FDG PET/CT can predict BMB results with high accuracy. F-18 FDG PET/CT may be used at initial staging of pediatric Hodgkin’s lymphoma as it uncovers unsuspected BMI and BMB may be omitted in patients with PET-positive BMI.  相似文献   
122.
The recently discovered iron regulatory peptide hormone hepcidin holds promise as a novel biomarker in iron metabolism disorders. To date, various mass spectrometry and immunochemical methods have been developed for its quantification in plasma and urine. Differences in methodology and analytical performance hinder the comparability of data. As a first step towards method harmonization, several hepcidin assays were compared. Worldwide eight laboratories participated in a urinary and plasma round robin in which hepcidin was analyzed. For both urine and plasma: (i) the absolute hepcidin concentrations differed widely between methods, (ii) the between-sample variation and the analytical variation of the methods are similar. Importantly, the analytical variation as percentage of the total variance is low for all methods, indicating their suitability to distinguish hepcidin levels of different samples. Spearman correlations between methods were generally high. The round robin results inform the scientific and medical community on the status and agreement of the current hepcidin methods. Ongoing initiatives should facilitate standardization by exchanging calibrators and representative samples.  相似文献   
123.
Cyclooxygenase-2 (COX-2) is implicated in pathophysiological processes associated with the initiation or maintenance of host inflammatory responses to infection. Our results demonstrates that Mycobacterium bovis BCG ( M. bovis BCG) downregulates tumour necrosis factor-α (TNF-α)-induced COX-2 gene expression in alveolar epithelial cells by inhibiting the phosphorylations of Raf-1 and p38 kinases. Further, M. bovis BCG-mediated inhibition of COX-2 or p38 mitogen-activated protein kinase could be reversed by Calyculin A, a selective inhibitor of Ser/Thr phosphatases. Moreover, M. bovis BCG inhibited the TNF-α-triggered NF-κB activation following IκB degradation. Taken together, these results suggest that the attenuation of COX-2 expression by vaccine strain, M. bovis BCG, represents a novel strategy to maintain robust host proinflammatory responses to subsequent challenges with virulent tuberculosis bacilli.  相似文献   
124.
125.
Sridhar MS  Murthy S  Bansal AK  Rao GN 《Cornea》2000,19(3):333-335
PURPOSE: We report the indications, complications, and outcomes of 104 corneal triple procedures in our institute. METHODS: Patient records of 104 consecutive cases of corneal triple procedure (penetrating keratoplasty with extracapsular cataract extraction and intraocular lens implantation) performed by experienced corneal surgeons between January 1992 and December 1997 were retrospectively reviewed. Relevant preoperative, operative, and postoperative data were collected. The outcome was assessed by the graft clarity and visual acuity at the last visit. Survival analysis of these grafts was determined by Kaplan-Meier method. RESULTS: Of 104 patients, 70 were men and 34 were women. Mean age of these patients was 48.5+/-17.1 years (range, 1-75 years). Corneal scarring with cataract was the reason for surgery in 69 (66.4%) cases. The intraoperative complications included vitreous upthrust in seven (6.9%) cases and posterior capsular dehiscence in three (2.9%) cases. The most common early postoperative complications were increased intraocular pressure in 19 (18.3%) and increased anterior chamber reaction in 25 (24%) cases. Posterior capsular opacification was seen in 26 (25%), graft reaction in 15 (14.4%), and secondary glaucoma in 15 (14.4%) cases. These formed the important late postoperative complications. The average postoperative follow-up was 23.7+/-17.6 months (range, 1.6-79.4 months); at which time 72% of the grafts remained clear. At last follow-up, 40% of patients had a visual acuity of > or = 20/40. CONCLUSIONS: Corneal scarring with cataract is the most common reason for triple procedure in this part of the world. This is a safe surgical procedure with good graft clarity and reasonable visual recovery.  相似文献   
126.
127.
We report a case of anterior chamber Cysticercus cellulosae that was removed by viscoexpression.  相似文献   
128.
We attempted to determine the level and form of selenium (Se) that yielded the maximum Se status of yeast cells, for their evaluation as a source of Se for chemopreventive action. The influence of various Se concentrations from organic (selenomethionine) and inorganic (sodium selenite) Se compounds on growth pattern and cell viability and the alterations in the antioxidant enzyme system of yeast were evaluated. A continuous decrease in cell and colony-forming units counts was observed with increasing concentrations of Se from either source. Increasing Se status of yeast cells was found with increasing concentrations of Se with both forms, with much greater uptake for organic Se at maximum Se concentrations. A continuous increase in glutathione peroxidase (GSH-Px) activity with increasing Se concentrations in both forms revealed an active Se response in terms of antioxidant activity, with a more pronounced percentage increase with selenomethionine. A highly significant increase in total glutathione was observed with selenomethionine supplementation, compared with sodium selenite. A decreasing trend in reduced glutathione was observed with increasing organic or inorganic Se concentrations. An increasing trend in glutathione-S-transferase activity was observed with increasing Se concentrations for both forms. Significantly higher values of glutathione-S-transferase were associated with the organic form at higher Se concentrations. There was normal activity of Se in mammalian cells. The results showed that an organic Se source more greatly enhances the Se status of yeast cells and hence could help in chemoprevention if consumed by the population.  相似文献   
129.
We report a rare case of high cervical intramedullary ependymal cyst in a young boy. This was associated with atlantoaxial dislocation. After partial removal and marsupialization, the cyst recurred and needed radical total resection.  相似文献   
130.
Sentinel lymph node (SLN) identification and biopsy in breast cancer have been carried out successfully since the early 1990s. In early-stage breast cancer, the negative predictive value of a SLN biopsy is as high as 93%-100%. With a negative SLN, no axillary treatment would be required and the breast can be treated by tangential radiation fields. Currently, for a patient with a positive SLN, axillary dissection is recommended. Axillary irradiation can replace surgery with a low risk of recurrence (< 7%). The modern practice of radiotherapy, delivering a dose of 50 Gy to the axilla, has a low rate of late morbidity. Hence, it is now time to plan clinical trials comparing axillary irradiation with axillary dissection in SLN-positive, early-stage breast cancer. These approaches to the axilla, guided by the status of the SLN can reduce arm problems in women with breast cancer and improve their quality of life. Just as the treatment of the primary breast tumour has changed from Halstedian mastectomy to conservation surgery combined with breast irradiation, SLN biopsy may allow a move away from surgical axillary clearance and the associated morbidity in the future.  相似文献   
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