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91.

Purpose

The aim of this study was to investigate relationships between the immunohistochemical results and radioiodine scan and 18F-FDG PET findings in papillary thyroid cancer (PTC) patients with recurrent cervical nodal metastases.

Methods

A total of 46 PTC patients who had undergone a radioiodine scan and/or 18F-FDG PET/CT and a subsequent operation on recurrent cervical lymph nodes were enrolled. Twenty-seven patients underwent 18F-FDG PET/CT, 8 underwent radioiodine scans, and 11 underwent both scans. In all surgical specimens, the immunoexpressions of thyroglobulin (Tg), sodium-iodide symporter (NIS), glucose transporter 1 (Glut-1), and somatostatin receptor 1 and 2A (SSTR1 and SSTR2A) were assessed, and associations between these expressions and radioiodine scan and 18F-FDG PET findings were evaluated.

Results

Of the 38 patients who underwent 18F-FDG PET/CT, all patients with weak Tg expression had positive 18F-FDG uptake, while only 45 % of the patients with moderate or strong Tg expression showed positive uptake (p = 0.01). The proportion of patients with positive 18F-FDG uptake increased as the degree of Glut-1 expression with luminal accentuation increased. Of the 19 patients who underwent a radioiodine scan, the proportion with positive radioiodine uptake was greater among patients with strong NIS and SSTR2A expression than among patients expressing these markers at weak levels (p = 0.04 for all). All three patients with weak Tg expression were negative for radioiodine uptake.

Conclusion

The 18F-FDG uptakes of recurrent cervical nodes are related to strong Glut-1 expression with luminal accentuation and weak Tg expression, whereas radioiodine uptake is related to the strong expressions of NIS and SSTR2A.  相似文献   
92.
Uncontrolled type 2 diabetes mellitus (T2DM) and post-transplant diabetes mellitus (PTDM) increase morbidity and mortality after kidney transplantation. Conventional strategies for diabetes management in this population include metformin, sulfonylureas, meglitinides and insulin. Limitations with these agents, as well as promising new antihyperglycemic agents, create a need and opportunity to explore additional options for transplant diabetes pharmacotherapy. Novel agents including sodium glucose co-transporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP1RA), and dipeptidyl peptidase IV inhibitors (DPP4i) demonstrate great promise for T2DM management in the non-transplant population. Moreover, many of these agents possess renoprotective, cardiovascular, and/or weight loss benefits in addition to improved glucose control while having reduced risk of hypoglycemia compared with certain other conventional agents. This comprehensive review examines available literature evaluating the use of novel antihyperglycemic agents in kidney transplant recipients (KTR) with T2DM or PTDM. Formal grading of recommendations assessment, development, and evaluation (GRADE) system recommendations are provided to guide incorporation of these agents into post-transplant care. Available literature was evaluated to address the clinical questions of which agents provide greatest short- and long-term benefits, timing of novel antihyperglycemic therapy initiation after transplant, monitoring parameters for these antihyperglycemic agents, and concomitant antihyperglycemic agent and immunosuppression regimen management. Current experience with novel antihyperglycemic agents is primarily limited to single-center retrospective studies and case series. With ongoing use and increasing comfort, further and more robust research promises greater understanding of the role of these agents and place in therapy for kidney transplant recipients.  相似文献   
93.
We reviewed 27 cases of tibial bone defects treated by internal bone transport using the Ilizarov method. The causes of the bone defects were open fractures in 14 segments and infected non-unions in 13. The average length of the defects was 8.3 cm (range, 3–20 cm). There were 21 one-level tibial transports, 3 two-level tibial transports, 1 one-level tibial transport with fibular transport, and 2 fibular transports. At the docking site, 25 segments underwent bone grafting. Eleven of the 25 were Papineau-type open cancellous bone grafts. Acute shortening or docking was performed in 10 segments. Bone union was obtained in every instance. The average time of external fixation was 8 months and the average time to union was 7.1 months. Bone grafting at the docking site is recommended in order to shorten the duration of treatment and to prevent refracture and non-union.
Résumé. Nous avons passé en revue 27 cas de perte de substance du tibia traités par ?transport osseux interne? conformément à la méthode Ilizarov. Ces anormalies provenaient de fractures ouvertes dans 13. La longeur moyenne des defect osseux était de 8,3 cm (entre 3 et 20 cm). On a effectué 21 ?transports tibiaux? de niveau 1, 3 ?transports tibiaux? de niveau 2, 1 ?transport tibial? avec ?transport du péroné?, ainsi que 2 ?transport du péroné?. Dans 25 cas une greffe osseuse a été pratiquée sur le site de réduction. 11 cas des 25 greffes pratiquées étaitent du type Papinau. D’importances réduction ont d?étre effectuées dans 10 cas. Des fusions ont été obtenues dans tous les cas. Le temps moyen de fixation externe était de 8 mois et celui de fusion de 7,1 mois. La greffe osseuse est recommandée sur le site de réduction afin de raccourcir la durée du traitement et de prévenir toute récidive de fracture ou de non-consolidation.


Accepted: 7 November 1997  相似文献   
94.

Purpose

Texture analysis on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scan is a relatively new imaging analysis tool to evaluate metabolic heterogeneity. We analyzed the difference in textural characteristics between non-small cell lung carcinoma (NSCLC) subtypes, namely adenocarcinoma (ADC) and squamous cell carcinoma (SqCC).

Methods

Diagnostic 18F-FDG PET/computed tomography (CT) scans of 30y patients (median age, 67; range, 42-88) with NSCLC (17 ADC and 13 SqCC) were retrospectively analyzed. Regions of interest were manually determined on selected transverse image containing the highest SUV value in tumors. Texture parameters were extracted by histogram-based algorithms, absolute gradient-based algorithms, run-length matrix-based algorithms, co-occurrence matrix-based algorithms, and autoregressive model-based algorithms. Twenty-four out of hundreds of texture features were selected by three algorithms: Fisher coefficient, minimization of both classification error probability and average correlation, and mutual information. Automated clustering of tumors was based on the most discriminating feature calculated by linear discriminant analysis (LDA). Each tumor subtype was determined by histopathologic examination after biopsy and surgery.

Results

Fifteen texture features had significant different values between ADC and SqCC. LDA with 24 automate-selected texture features accurately clustered between ADC and SqCC with 0.90 linear separability. There was no high correlation between SUVmax and texture parameters (|r| ≤ 0.62).

Conclusion

Each subtype of NSCLC tumor has different metabolic heterogeneity. The results of this study support the potential of textural parameters on FDG PET as an imaging biomarker.  相似文献   
95.

Objectives

To assess the image quality of ultra-low-dose computed tomography (ULDCT) using sinogram-affirmed iterative reconstruction (SAFIRE) compared to reduced dose CT (RDCT).

Methods

Eighty-one consecutive patients underwent non-enhanced ULDCT using 80 kVp and 30 mAs and contrast-enhanced RDCT using automated tube potential selection and tube current modulation. CT images were reconstructed with SAFIRE. Image noise and subjective image quality of normal structures and various pulmonary lesions were assessed.

Results

The mean effective doses were 0.29?±?0.03 and 2.88?±?1.11 mSv for ULDCT and RDCT, respectively. ULDCT had significantly higher noise (p?<?0.001). Image quality of five normal structures was diagnostic in 91.1 % of ULDCT and 100 % of RDCT. With ULDCT, the frequencies of non-diagnostic image quality were 2.0 (1/50), 4.6 (13/280), 25.5 (14/55), and 40.0 (8/20)% for BMIs of?<?20, 20–25, 25–30, and >30. In the assessment of pulmonary lesions, non-diagnostic image quality was observed for 11.2 % of all lesions, 60.9 % of decreased attenuation (significantly more frequent for upper lung lesions), and 23.5 % of ground-glass nodules.

Conclusion

ULDCT generates diagnostic images in patients with a BMI ≤25, but is of limited use for lesions with decreased attenuation, ground-glass nodules, or those located in the upper lobe.

Key Points

? Iterative reconstruction enables ultra-low-dose CT (ULDCT) with very low radiation doses. ? Image quality of ULDCT depends on the patient body mass index (BMI). ? Selection of kVp and mAs depends on both BMI and lesion type. ? Diagnosis of pulmonary emphysema or ground-glass nodules requires higher radiation doses.  相似文献   
96.

Purpose

The new modality of an integrated positron emission tomography/magnetic resonance imaging (PET/MRI) has recently been introduced but not validated. Our objective was to evaluate clinical performance of 18F-fluoro-2-deoxyglucose (18F-FDG) PET/MRI in patients with head and neck cancer.

Methods

This retrospective study was conducted between January 2013 and February 2013. Ten patients (eight men, two women; mean age, 61.4 ± 13.4 years) with histologically proven head and neck tumors were enrolled. Whole-body PET/MRI and regional positron emission tomography (PET) with dedicated MRI were sequentially obtained. Maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume, total lesion glycolysis and contrast enhancement were analyzed. A total of ten whole-body positron emission tomography (PET), ten regional positron emission tomography (PET), ten dedicated MRI and ten regional PET/gadolinium-enhanced T1-weighted (Gd)-MRI images were analyzed for initial staging. Two nuclear medicine physicians analyzed positron emission tomography (PET) and PET/MRI with a consensus. One radiologist analyzed dedicated MRI. The primary lesions and number of metastatic lymph nodes analyzed from each image were compared.

Results

Eight patients were diagnosed with head and neck cancer (one tongue cancer, four tonsillar cancers, one nasopharyngeal cancer and two hypopharyngeal cancers) by histological diagnosis. Two benign tumors (pleomorphic adenoma and Warthin tumor) were diagnosed with surgical operation. Whole-body positron emission tomography (PET) and regional positron emission tomography (PET) attenuated by MRI showed good image quality for the lesion detection. Whole-body positron emission tomography (PET) and regional positron emission tomography (PET) detected ten primary sites and compensated for a missed lesion on dedicated MRI. A discordant number of suspicious lymph node metastases was noted according to the different images; 22, 16, 39 and 40 in the whole-body positron emission tomography (PET) only, dedicated MR, regional positron emission tomography (PET) only and regional PET/Gd-MRI, respectively. There was no distant metastasis based on analysis of whole-body positron emission tomography (PET) and whole-body PET/Dixon-volume interpolated breathhold examination (VIBE) MRI. Regional PET/Gd-MRI combined with whole-body PET/MRI modified staging in three patients. Lesions of primary tumor and suspicious metastasis were well detected on both value of SUVmax and visual analysis. The regional PET/Gd-MRI combined with whole-body PET/MRI showed convenient clinical staging performance compared with positron emission tomography (PET) and MRI alone.

Conclusion

In this preliminary study, PET attenuated by MRI showed good image quality to detect lesions. And whole-body PET/MRI as a single modality was feasible for staging in a clinical setting. Whole-body positron emission tomography (PET), regional positron emission tomography (PET), dedicated MRI and regional PET/Gd-MRI showed discordant results in lesion detection. These discordant results might be synergistic effect for accurate staging.  相似文献   
97.
We had an opportunity to perform replantation of both legs on a 2-year-old girl, and our decision to perform replantation rather than amputation surgery was carefully made taking her age, degree of crushing injury, ischaemic time and level of the amputation into consideration. Painstakingly designed rehabilitation treatments were continuously performed on this girl from the early stage after the operation, and the treatments were comprised of four parts; that is, flexion and extension exercise for the ankle in order to prevent it from stiffness or contracture, functional electrical stimulation (FES) in order to prevent muscular atrophy on the lower extremities, muscle strengthening exercise for the lower extremities, and electrical stimulation to regenerate the damaged nerves and to prevent muscular atrophy from occurring. For an objective assessment of the postoperative conditions, total active motion angles of the ankle joint were measured, and also EMG and NCV were conducted at the end of the first month as well as at the end of the 6th month. Total active motion angles of the ankle joint were increased progressively as time went on, from 15 to 60 degrees on the right and from 10 to 45 degrees on the left. NCV did not show any sensation or response from motor nerves, or amplitude decreased considerably 1 month after the operation; however, at the end of the 6th month conditions improved a great deal with both amplitude and latency. And most muscles that did not show any signals on EMG or showed less than normal at the end of the first month after the operation eventually recovered at the end of the 6th month. The patient had no particular difficulties in walking after 6 months or rather she started running in small steps showing her legs functioning superbly. An infant with both of lower extremities amputated is quite a rare case. We believe that the replantation surgery was successful due to the fact that carefully selected preoperative factors were taken into consideration and well designed postoperative rehabilitation program consisted of four parts was carried out continuously.  相似文献   
98.

Purpose

To compare the perioperative relative renal function and determine predictors of deterioration and recovery of separate renal function in patients with renal stones >10 mm and who underwent mini-percutaneous nephrolithotomy or retrograde intra-renal surgery.

Patients and methods

A main stone >10 mm or stones growing, high-risk stone formers and extracorporeal shock-wave lithotripsy-resistant stones were prospectively included in 148 patients. Patients with bilateral renal stones and anatomical deformities were excluded. Renal function was evaluated by estimated glomerular filtration rate, 99m-technetium dimercaptosuccinic acid and 99m-technetium diethylenetriamine pentaacetate prior to intervention and at postoperative 3 months. Logistic regression analyses were performed to find predictors of functional deterioration and recovery.

Results

The overall stone-free rate was 85.1 %. A third of patients (53/148, 35.8 %) with renal stones >10 mm showed deterioration of separate renal function. Mean renal function of operative sites showed 58.2 % (36.8 %/63.2 %) of that of contralateral sites in these patients. Abnormal separate renal function showed postoperative recovery in 31 patients (58.5 %). Three cases (5.7 %) showed deterioration of separate renal function despite no presence of remnant stones. Improvement rates of the abnormal separate renal function did not differ according to the type of surgery. The presence of hydronephrosis and three or more stones were significant predictors for renal function deterioration. Female gender and three or more stones were significantly correlated with postoperative recovery.

Conclusions

Mini-percutaneous nephrolithotomy or retrograde intra-renal surgery was effective and safe for renal function preservation. Patients with multiple large stones should be considered for candidates of active surgical removal.
  相似文献   
99.

Purpose

Curcumin, a biphenolic compound extracted from turmeric (Curcuma longa), possesses potent anti-inflammatory activity. The present study investigated whether curcumin could increase 5′ adenosine monophosphate-activated protein kinase (AMPK) activity in macrophages and modulate the severity of lipopolysaccharide (LPS)-induced acute lung injury.

Methods

Macrophages were treated with curcumin and then exposed (or not) to LPS. Acute lung injury was induced by intratracheal administration of LPS in BALB/c mice.

Results

Curcumin increased phosphorylation of AMPK and acetyl-CoA carboxylase (ACC), a downstream target of AMPK, in a time- and concentration-dependent manner. Curcumin did not increase phosphorylation of liver kinase B1, a primary kinase upstream of AMPK. STO-609, an inhibitor of calcium2+/calmodulin-dependent protein kinase kinase, diminished curcumin-induced AMPK phosphorylation, but transforming growth factor-beta-activated kinase 1 inhibitor did not. Curcumin also diminished the LPS-induced increase in phosphorylation of inhibitory κB-alpha and the production of tumor necrosis factor alpha (TNF-α), macrophage inflammatory protein (MIP)-2, and interleukin (IL)-6 by macrophages. Systemic administration of curcumin significantly decreased the production of TNF-α, MIP-2, and IL-6 as well as neutrophil accumulation in bronchoalveolar lavage fluid, and also decreased pulmonary myeloperoxidase levels and the wet/dry weight ratio in mice subjected to LPS treatment.

Conclusion

These results suggest that the protective effect of curcumin on LPS-induced acute lung injury is associated with AMPK activation.
  相似文献   
100.
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