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991.

Objective

Besides cardiac sarcoidosis, FDG-PET is rarely used in the diagnosis of myocardial inflammation, while cardiac MRI (CMR) is the actual imaging reference for the workup of myocarditis. Using integrated PET/MRI in patients with suspected myocarditis, we prospectively compared FDG-PET to CMR and the feasibility of integrated FDG-PET/MRI in myocarditis.

Methods

A total of 65 consecutive patients with suspected myocarditis were prospectively assessed using integrated cardiac FDG-PET/MRI. Studies comprised T2-weighted imaging, late gadolinium enhancement (LGE), and simultaneous PET acquisition. Physiological glucose uptake in the myocardium was suppressed using dietary preparation.

Results

FDG-PET/MRI was successful in 55 of 65 enrolled patients: two patients were excluded due to claustrophobia and eight patients due to failed inhibition of myocardial glucose uptake. Compared with CMR (LGE and/or T2), sensitivity and specificity of PET was 74% and 97%. Overall spatial agreement between PET and CMR was κ = 0.73. Spatial agreement between PET and T2 (κ = 0.75) was higher than agreement between PET and LGE (κ = 0.64) as well as between LGE and T2 (κ = 0.56).

Conclusion

In patients with suspected myocarditis, FDG-PET is in good agreement with CMR findings.
  相似文献   
992.

Background and purpose

Current prognostic models for soft tissue sarcoma (STS) patients are solely based on staging information. Treatment-related data have not been included to date. Including such information, however, could help to improve these models.

Materials and methods

A single-center retrospective cohort of 136 STS patients treated with radiotherapy (RT) was analyzed for patients’ characteristics, staging information, and treatment-related data. Therapeutic imaging studies and pathology reports of neoadjuvantly treated patients were analyzed for signs of response. Random forest machine learning-based models were used to predict patients’ death and disease progression at 2 years. Pre-treatment and treatment models were compared.

Results

The prognostic models achieved high performances. Using treatment features improved the overall performance for all three classification types: prediction of death, and of local and systemic progression (area under the receiver operatoring characteristic curve (AUC) of 0.87, 0.88, and 0.84, respectively). Overall, RT-related features, such as the planning target volume and total dose, had preeminent importance for prognostic performance. Therapy response features were selected for prediction of disease progression.

Conclusions

A machine learning-based prognostic model combining known prognostic factors with treatment- and response-related information showed high accuracy for individualized risk assessment. This model could be used for adjustments of follow-up procedures.
  相似文献   
993.
994.
995.
Filtering procedures have been the gold standard in glaucoma surgery for more than 30 years. Trabeculotomy, deep sclerectomy, and viscocanalostomy might become the procedures of first choice in the future. These new, non-penetrating procedures have not yet been compared to filtering procedures in prospective randomized studies with long-term follow-up. In addition, it is not really known how they modify outflow of the aqueous humor. The surgical technique is described and the most likely underlying effects are discussed.  相似文献   
996.
BACKGROUND: GPs have many patients with gastrointestinal discomfort. Among bowel-related complaints, the sign of rectal bleeding is of particular importance in patients aged 50 years and above, as it can be an early sign for serious bowel diseases such as colon carcinoma. Despite many guidelines offered to GPs for screening and early detection of colorectal carcinomas, there is very little information about the actual diagnostic approach to the sign of rectal bleeding. AIM: The aim of the study was to collect data concerning treatment strategies used by GPs who treat patients presenting with rectal bleeding. DESIGN OF STUDY: Prospective data collection. SETTING: General practices in Germany. METHOD: Over the course of a year, GPs recorded their treatment strategies in patients presenting with rectal bleeding and associated symptoms. Using a digital practice patient file, physicians participating in the study were able to continuously transmit data electronically to the researchers of the study about diagnostics, referrals, hospital admissions, and final diagnoses. RESULTS: During the course of 1 year, 94 participating physicians collected data on 1584 patients. Information about treating rectal bleeding was recorded for 422 patients; 60% of the patients were referred to specialists in internal medicine or gastroenterologists for further diagnostics. A colonoscopy was the most frequently performed diagnostic procedure (46.2%). Twenty-two per cent (n = 93) of the patients--54 of them aged 50 years and above--were exclusively treated by their GP without conducting a colonoscopy or cooperating with specialists. For these patients, GPs diagnosed less severe diseases like haemorrhoids or other proctologic diseases. CONCLUSION: By using a study that allows GPs to transmit electronically their findings and data, it is possible to draw a picture of treatment strategies of GPs in patients presenting with rectal bleeding. The high percentage of patients who received medical treatment in consultation with specialists underscores the significance of the sign of rectal bleeding in general practice. The need for further diagnostic measures in patients who have been treated exclusively by GPs has to be discussed.  相似文献   
997.
998.
The presence of immunoglobulin crystal inclusions in plasma cells from plasmacytomas and B-NHLs (linked to overstimulation and overproduction) has been frequently reported. Our case describes a lymphoplasmacellular synovitis in a patient with osteoarthritis (OA) showing an unusually high plasma cell infiltration and for the first time crystals in plasma cells. Using immunohistochemistry. these crystals were identified as being IgG with a balanced lambda/kappa ratio. IgV(H) gene analysis (n = 5 clones) showed that they were somatically mutated (R/S of CDR > 3): in one case, an insertion of 9 nucleotides on the CDR2 region was observed. High R/S values in the CDR indicated antigen selectivity and affinity (4/5). Since no germinal centers could be detected and the analyzed B cells showed antigen selectivity, it may be concluded that already antigenically activated B cells migrated into the synovium and locally differentiated into plasma cells, leading to the extensive infiltration observed. Rheumatoid fibroblasts were shown to support terminal B cell differentiation. Our data suggests that the ability of fibroblasts to activate B cells is not only restricted to RA, but also occurs in OA. The intense plasma cell infiltration contributed to further cartilage damage by altering the microenvironment of the nourishing synovial tissue or by the local production of pathogenic autoantibodies.  相似文献   
999.
1000.
SUMMARY: The pathomechanisms that cause renal damage in diabetes have not been completely clarified. Treatment with angiotensin-converting enzyme inhibitors (ACE-i) is highly effective but fails to completely prevent end-stage renal disease. The effects of ET(A)-receptor blockers (ET(A)-RB) on renal damage are controversial and have rarely been investigated in type 2 diabetes. We compared the influence of the selective ET(A)-RB LU135252 and the ACE-i Trandolapril on renal structure in the SHR/N-cp rat model of type 2 diabetes. Three-month-old male SHR/N-cp rats were left untreated or received daily either Trandolapril or LU135252. The experiment was terminated after 6 months. The glomerulosclerosis index; tubulointerstitial damage index; and glomerular geometry, glomerular cell number, and capillary density were investigated. Proliferating cell nuclear antigen and desmin expression of podocytes, renal mRNA expression of endothelin (ET-1) and transforming growth factor-beta, blood pressure, and urine albumin excretion were measured. The glomerulosclerosis index was significantly higher in untreated diabetic animals than in the groups that were treated with ACE-i and ET(A)-RB. There were analogous changes in tubulointerstitial damage index. Treatment with either substance comparably lowered urinary albumin excretion in diabetic SHR/N-cp. Podocyte and endothelial cell numbers per glomerulus decreased in untreated diabetic animals; this was prevented by the ACE-i but not by the ET(A)-RB. Glomerular capillary length density was lower in SHR/N-cp, and this was normalized by ACE-i only. Increased expression of desmin and proliferating cell nuclear antigen expression of podocytes in the SHR/N-cp was abrogated by ACE-i but not by ET(A)-RB. Treatment with ACE-i or ET(A)-receptor antagonist resulted in less structural and functional alterations, but the ET(A)-RB was inferior to the ACE-i. This is particularly the case for podocyte changes pointing to angiotensin II-dependent pathomechanisms.  相似文献   
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