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31.
Whole body radioiodine scanning (WBS), along with plasma thyroglobulin level, remains a reference method for detecting residual or metastatic differentiated thyroid cancer, however, false-positive WBS is not uncommon. External contaminations by body secretions or excretions, inflammation, and cystic structures mimicking metastases in WBS have been reported. Various benign and malignant tumors having different histopathological natures accumulate radioiodine, but intradermal melanocytic nevus was not previously described in the literature, as far as we know. This report describes an unusual cause of false-positive WBS after radioablation therapy due to an intradermal nevus, and the possible mechanisms are discussed.  相似文献   
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Objective

The target of radioiodine ablation therapy (RIAT) after complete tumor removal is the nontumoral remnant tissue. We aimed to evaluate sodium iodide symporter (NIS) expression in nontumoral thyroid tissue in differentiated thyroid cancer (DTC) patients who have complete but delayed structural response (DSR) to RIAT after surgery. Preoperative thyroid characteristics such as volume and nontumoral histology were also investigated for both DSR and its control group as potential predictors of insufficient NIS activity in this study.

Methods

Total of 600 patients with postoperative remnant thyroid tissue and who were in remission after RIAT spontaneously, were included in the study. Patients with positive diagnostic whole body scan (DxWBS) with thyroid bed uptake and stimulated serum Tg level <2 ng/mL at first year visit after initial therapy were defined as DSR group. Immunohistochemical staining of NIS protein was performed on the nontumoral tissue sections from surgery and semi quantified in terms of density and intensity. DSR and its control group were also compared in terms of NIS expression, radioiodine (RAI) uptake on post-therapy scan and preoperative thyroid characteristics.

Results

When compared with the control group, the density and intensity of NIS expression as well as the intensity of RAI uptake were significantly lower in DSR group (p = 0.001). There were also significant differences between groups regarding preoperative thyroid characteristics; i.e. preoperative thyroid volumes were significantly higher and the presence of concurrent benign thyroid disease was significantly more common in DSR group (p = 0.035, p = 0.001). Hashimoto thyroiditis was 8.59 times higher (95 % CI; 2.31–31.96) and multinodular goiter was 7.50 times higher (95 % CI; 1.88–29.91) among DSR group when compared with the control group.

Conclusions

Our findings suggest that insufficient NIS activity in nontumoral thyroid tissue associates with DSR in DTC patients who have postoperative remnant tissue. Preoperative thyroid characteristics such as volume and concomitant benign thyroid disease may have an important role in predicting the complete response time to RIAT in these patients.  相似文献   
34.

Objectives

Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center.

Materials and methods

Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities.

Results

The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically signi?cant difference was not detected between the sexes regarding LVC (P = 0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal–apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected.

Conclusion

Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.  相似文献   
35.
We have characterized a novel mutation in a male patient that affects the coding sequence of PDH-E1 gene and changes arginine-141 to a leucine. This nucleotide substitution was found in about 75% of the studied DNA (fibroblasts, liver and muscle), a scenario that would indicate a case of E1 mosaicism in a male patient. When the mutant E1 protein was expressed in human skin fibroblasts with zero endogenous pyruvate dehydrogenase complex activity and E1 protein expression, no significant restoration of activity was recorded, in contrast to the wild-type cDNA, even though both wild-type and mutant protein levels were comparable. We concluded that the R141L mutation is a severe one and that it must have occurred in one of the E1 alleles during early embryogenesis.  相似文献   
36.
Tracheobronchial-angle tumors involve the right main bronchus, the right upper lobar bronchus, and the lateral wall of the lower trachea. Resecting these tumors is one of the most complex procedures in thoracic surgery. In cases of high-caliber mismatch, the selection of a suitable anastomotic technique can be challenging. We found that our use of a one-stoma carinoplasty technique overcame high-caliber mismatch after the resection of these tumors.From 2009 through 2012, 8 men (mean age, 59 ± 6.2 yr; range, 46–66 yr) underwent complete resection of non-small-cell right-tracheobronchial-angle tumors at our institution. In every case, right upper sleeve lobectomy, wedge carinal resection, and one-stoma carinoplasty were applied.After tumor resection, one patient with hemoptysis and bronchopleural fistula underwent a completion pneumonectomy and died 10 days postoperatively. Bronchoscopy was necessary in 2 patients who had atelectasis in the contralateral lung. At a mean follow-up duration of 19.43 ± 8.4 months (range, 0.2–27.1 mo), 6 patients were alive and free of disease.We conclude that our one-stoma carinoplasty technique enables the resection of tumors at the right tracheobronchial angle, with acceptable morbidity and mortality rates. This method saves the unaffected part of the ipsilateral lung and can overcome high-caliber mismatch. Because of these and other advantages, we suggest that using our method first might preclude having to perform a right carinal sleeve pneumonectomy or using Barclay''s method.Key words: Bronchi/pathology/surgery, bronchial neoplasms/surgery, carcinoma, squamous cell/surgery, reconstructive surgical procedures/methods, trachea/surgery, treatment outcomeResecting tracheobronchial-angle tumors is complex, and carinal resection and reconstruction is one of the most problematic techniques in thoracic surgery. There is no ideal technique for the surgical reconstruction, the technical difficulty of which is accompanied by possible devascularization, separation, and stenosis.Right carinal pneumonectomy and lobectomy are challenging operations that are performed in less than 1% of non-small-cell lung cancer patients.1,2 Tracheobronchial-angle tumors are typically classified within the broader category of carinal tumors and are not considered to warrant a particularly different treatment. However, tracheobronchial-angle tumors do not completely invade the carina: they involve the right main bronchus, the right upper lobar bronchus, and the lateral wall of the lower trachea.The surgical technique that we applied in our patients was used by Grillo3 in a patient with tracheal cystic adenoma. Tanaka and colleagues4 used the same technique in treating a patient who had benign stricture of the right main bronchus. We found no other report that described the application of this technique.  相似文献   
37.
Reactive oxygen species (ROS) have been postulated to play a major role in postischemic acute renal injury. Moreover, lipid peroxidation has been described as an important pathway of ROS-induced postischemic acute renal failure. To evaluate effects of selenium (Se) and trimetazidine (TMZ) on postischemic renal failure, renal tissue malondialdehyde (MDA) and superoxide dismutase (SOD) concentrations were measured in Wistar rats with ischemic renal failure. Treatment groups consisted of rats treated with TMZ (5 mg/kg orally) or Se (30 μg/kg orally) or TMZ+Se for 15 days. Ischemic groups consisted of rats with clamped left renal arteries for 1 hour. Before left renal arterial clamping, right nephrectomy was performed; after 24 hours, left nephrectomy was done. The animals were divided into 5 groups. Group 1 (n=7) was the nonischemic control group without treatment; Group 2 (n=6) was the ischemic control group treated with physiologic solution; Group 3 (n=5) received TMZ; Group 4 (n=5) received Se; and Group 5 (n=6) received TMZ+Se for 15 days. After TMZ and Se treatment, right renal tissue MDA significantly decreased in Groups 3–5 when compared with those in Group 1. There was no significant difference between non-ischemic and ischemic renal tissue MDA in Groups 3, 4, and 5. Postischemic renal tissue SOD levels were higher than nonischemic levels in Group 3. In Groups 4 and 5, no significant differences were observed between nonischemic and ischemic renal tissue SOD levels. Moreover, total scores obtained from histopathologic evaluation of ischemic and nonischemic kidney samples in Groups 3, 4, and 5 were similar, but these scores in Group 2 were significantly different from those of Groups 3, 4, and 5. These results indicate that, under these study conditions, TMZ, Se, and TMZ+Se treatments prevent lipid peroxidation in ischemic and nonischemic renal tissue. Moreover, these treatments prevent histologic findings of postischemic-perfusion renal injury.  相似文献   
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PURPOSE: The purpose was to determine whether the diffusion weighted imaging (DWI) was able to differentiate necrotic tumor or metastatic lesions from infected necrotic lesions such as abscesses and necrotic lymphadenitis in the neck. MATERIALS AND METHODS: DWI was performed on 37 consecutive patients with 85 head and neck necrotic and cystic lesions. The lesions were classified into four categories: metastatic lymph node involvement including lymphoma, necrotic tumor, abscesses and necrotic lymphadenitis. Each lesion was histopathologically studied and proved. RESULTS: In 12 patients, there were 35 necrotic lymphadenitis (necrotic tuberculosis lymphadenitis, n=18; necrotic nonspecific suppurative lymphadenitis, n=17). Of the 15 necrotic metastatic nodes, 11 lesions were lymphomatous involvement and 4 lesions were other tumor involvement. Other 11 patients have abscesses. Thirteen primary tumoral necrotic lesions arose in the neck of nine patients. All of the abscesses and necrotic lymphadenitis showed hyperintensity on DWI, in contrast to necrotic tumor and necrotic nodal metastasis that showed hypointensity on DWI. DWI successfully differentiated metastatic nodes and necrotic tumors from necrotic lymphadenitis and abscesses. CONCLUSION: DWI may be supportive for differentiating necrotic tumor lesions such as necrotic tumor and metastatic necrotic nodes from the infective necrotic lesions such as necrotic lymphadenitis and abscesses in the head and neck.  相似文献   
40.
Crimean-Congo hemorrhagic fever (CCHF) is a viral hemorrhagic fever, which is common in Turkey and globally. The pathogenesis of coagulation disorders, which is seen in viral hemorrhagic fevers remains to be elucidated. Thrombin-activatable fibrinolysis inhibitor (TAFI) has a key role in this process In this study, we aimed to evaluate whether TAFI levels contributed to bleeding and whether it is related to prognosis in CCHF patients. Eighty-four patients older than 15 years of age, who were admitted to our hospital who had positive immunoglobulin M (enzyme-linked immunosorbent assay [ELISA]) and/or polymerase chain reaction test results for CCHF between 2009 and 2010, were included in the study. The control group included 30 healthy adults. The plasma TAFI levels were compared between patients and controls, and also between patients with bleeding and no bleeding, and between patients with mild-moderate and severe disease. The mean TAFI levels were lower in patients (mean: 87.82 ng/ml, median: 61.69 ng/ml (interquartile range [IQR] 30.49–537.95) than controls (mean: 313.5 ng/ml with a median: 338.5 ng/ml (IQR 182–418). However, median TAFI levels were significantly higher in patients with bleeding compared to those without bleeding (78.99 and 50.28 ng/ml, respectively; p = 0.032). Median IQR TAFI levels were similar between patients with mild-moderate and severe disease (64.72 (41.37–113.85), and, 58.66 (42.44–118.93) ng/ml, respectively; p = 0.09) and survivors and nonsurvivors (86.14 ± 77.98 and 103.48 ± 69.92, respectively; p = 0.3). Although TAFI levels were lower in the patients with CCHF compared to healthy controls, it does not seem to be a major player in the prognosis.  相似文献   
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