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991.
BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is, aside skin cancer, the most common malignancy occurring after solid organ transplant in adults. Fluorodeoxyglucose (FDG) positron emission tomography (PET) has proved useful in the management of lymphomas. METHODS: We report our experience with the use of FDG-PET inline with computed tomography (CT) scanning in the management of four transplant recipients with histologically confirmed PTLD, including three monomorphic PTLDs and one polymorphic PTLD. RESULTS: FDG-PET/CT scan at diagnosis showed increased FDG uptake in all examined PTLD lesions, and the disease was upstaged on the basis of FDG-PET/CT scan results over conventional CT scanning in one patient. At the end of treatment, PET/CT scans no longer demonstrated FDG uptake in the original PTLD lesions in all patients. Complete remission of disease persisted for at least 1 year after diagnosis in all. CONCLUSIONS: Our results strongly support that FDG-PET scanning is highly specific for diagnosis and follow-up of PTLD. The clinical relevance of including FDG-PET/CT scanning in the management of PTLD should be evaluated in a larger prospective cohort study.  相似文献   
992.
Background  The mechanisms by which increased body weight influence bone mass density (BMD) are still unknown. The aim of our study was to analyze the relationship between anthropometric and body composition variables, insulin growth factor-I (IGF-I), adiponectin and soluble tumor necrosis factor-α receptors (sTNFR) 1 and 2 with BMD in two cohorts of morbid obese patients, before and after bypass surgery. Methods  The first cohort included 25 women aged 48 ± 7.6 years studied before bypass surgery. The second included 41 women aged 46 ± 9.2 years, 12 months after surgery. We studied anthropometric variables obtained from whole body DEXA composition analysis. Serum IGF-I, intact serum parathyroid hormone, 25-hydroxivitamin D3, plasma adiponectin concentrations, sTNFR1, sTNFR2 concentrations were measured. Results  In the first cohort, the BMI was 44.5 ± 3.6 kg/m2, parathyroid hormone, IGF-I, and adiponectin concentrations were lower, and sTNFR1 concentrations were higher than in the second cohort. In the multiple regression analysis, BMD remained significantly associated with body fat percentage (β −0.154, p = 0.01), lean mass (β 0.057, p = 0.016) and phosphate concentration (β 0.225, p = 0.05). In the second cohort, BMI was 31 ± 5.1 kg/m2. In the multiple regression analysis, BMD remained significantly associated with lean mass (β 0.006, p = 0.03). Conclusion  The inverse correlation found between body fat and BMD in the first cohort indicates morbid obesity increases the risk of osteoporosis and we found a positive correlation with lean and fat mass before bariatric surgery and with lean mass after bypass surgery.  相似文献   
993.
Background: Patients with primary hyperparathyroidism usually show decreased bone strength that are often not well diagnosed by conventional Dual-energy X-ray absorptiometry (DXA). Trabecular Bone Score (TBS) is a new technique for assessing bone microarchitecture indirectly. This cross-sectional study evaluates the usefulness of TBS in patients with primary hyperparathyroidism in clinical practice. Methodology: Bone mineral density (BMD) by DXA and TBS values by TBS InSight® software were determined in 72 patients with primary hyperparathyroidism to analyze its relationship with fragility fractures. A receiver operating curve was performed to evaluate the usefulness of TBS as predictor of fragility fractures. FRAX index with and without adjustment by TBS was calculated. Additionally, longitudinal data of a subgroup of patients according to the therapeutic management were also evaluated. Results: A total of 51.4% of the patients showed degraded microarchitecture while only 37.5% of them were diagnosed of osteoporosis by DXA. No significant correlation was found between TBS values and BMD parameters. However, TBS values were lower in osteoporotic patients compared to those classified as normal by BMD (1.16 ± 0.12vs 1.26 ± 0.17; p?=?0.043) and in patients with fragility fractures compared to nonfractured patients (1.19 ± 0.03vs 1.24 ± 0.02, p < 0.001). The area under the curve for TBS performed better than the combination of femoral, hip and spine-BMD for prevalent fractures (0.714vs 0.679). TBS-adjusted FRAX was higher than nonadjusted model for both major osteoporotic and hip fracture (4.5% vs 3%; 0.9% vs 0.7%; p < 0.001). At follow-up, an improvement in TBS values was observed in treated patients (medical or surgical) vs nontreated close to significance (1.27 ± 0.10vs 1.24 ± 0.11, p?=?0.074). Conclusions: TBS could be a useful tool to identify increased fracture risk in patients with primary hyperparathyroidism underdiagnosed by BMD. Moreover, FRAX adjusted by TBS could be a more robust tool for predicting the risk of osteoporotic fracture to help in therapeutic decisions in this population.  相似文献   
994.

Introduction

Patients with resistant hypertension (RH) have a high risk of developing cardiovascular events; therefore, new therapeutic approaches to better control blood pressure may be useful in improving cardiovascular outcomes. The prevalence of obstructive sleep apnea (OSA) is very high among patients with RH. Continuous positive airway pressure (CPAP) has been shown to be an effective treatment for reducing blood pressure in patients with RH. Nevertheless, the long-term effect of CPAP treatment on cardiovascular outcomes has not been explored.The main objective of the SARAH study is to assess the impact of OSA and its treatment on cardiovascular outcomes (morbidity and mortality) in patients with RH.

Methods

This study is a multi-center, prospective, observational cohort study. A total of 1371 patients with RH will be enrolled in the study and followed once a year for five years. At inclusion, ambulatory blood pressure monitoring (ABPM) and a sleep study will be performed in all subjects. Socio-demographic, clinical and cardiovascular variables will be collected at baseline and follow-up. Subsequently, subjects with OSA will be managed according to local standard practice. Based on the OSA diagnosis and its treatment, three cohorts of subjects with RH will be defined: non-OSA, treated OSA and non-treated OSA.

Conclusions

This study will contribute to elucidating the long-term impact of OSA treatments on blood pressure control and cardiovascular outcomes in patients with RH. These results will contribute to improve the cardiovascular prognosis of patients with RH.  相似文献   
995.
BACKGROUND: Endoscopic management of laryngeal carcinoma has gained popularity among laryngologists based on the good oncologic and functional results. We evaluated the voice quality after laser cordectomy for early glottic cancer in a variety of vocal situations and its relation with the extension of resection and the age. METHODS: We conducted a cross-sectional study of voice quality in 42 consecutive male patients treated for T1 glottic carcinoma with laser cordectomy. Patients were compared with 21 controls. Voice quality was self-assessed by the patients. Perceptual analysis was done by a speech pathologist on a running speech sample [GRBAS (grade, roughness, breathiness, asthenicity, strain)]. Acoustic analysis included fundamental frequency (F0), jitter, shimmer, noise to harmonic ratio (N/H), and maximum phonation time (MPT) on the sustained vowels /a/ and /i/, and on various running speech voice samples. RESULTS: Distribution of the patients included in the study by T classification was as follows: Tis, n = 2 (4.8%); T1a, n = 35 (83.3%); and T1b, n = 5 (11.9%). Cordectomy types were: (I), 14%; (II), 26%; (III), 21%; and (V), 38%. Voice improved in almost 60% of patients, returning to normal in 45%. GRBAS showed significant differences between patients and controls and correlated with type of cordectomy. Acoustic analysis showed significant differences in F0, and jitter, with smaller differences in shimmer, N/H, and MPT. CONCLUSION: Voice quality after laser cordectomy differs from controls, but improves in a majority of patients after the surgery, with almost 50% of patients with subjective normal or near normal voice. Voice quality depends on type of cordectomy.  相似文献   
996.
997.
Two case reports illustrate the application of mnemonic techniques for the remediation of memory problems common to brain-damaged patients. A clinical paradigm for such work that includes general and specific assessment, laboratory evaluation of intervention strategies, and finally in-vivo application is described.  相似文献   
998.
Papillary tumor of the pineal region is a rare neuroepithelial tumor characterized by papillary architecture and epithelial cytology, immunopositivity for cytokeratin and ependymal differentiation. It is considered grade II–III by the World Health Organization and was first described by Jouvet in 2003. We present a 34-year-old male with headaches, blurred vision and normal examination. Radiological study showed a nodulocystic lesion in the pineal region compatible with pineocytoma. Surgery was performed using an infratentorial supracerebellar approach, finding a cystic tumor in the quadrigeminal cistern which was completely resected. Histopathology reported a papillary tumor of the pineal region. The patient made good progress without adjuvant therapy, and after 57 months of follow-up he remained asymptomatic and free of recurrence. A review of the literature was performed to collect all the cases published with gross total resection and no complementary treatment. In conclusion, there is still much to be learned about the pathogenesis, prognosis and management of this tumor.  相似文献   
999.
Spontaneous modulations of corticospinal excitability during action observation have been interpreted as evidence for the activation of internal motor representations equivalent to the observed action. Alternatively or complementary to this perspective, growing evidence shows that motor activity during observation of rhythmic movements can be modulated by direct visuomotor couplings and dynamical entrainment. In‐phase and anti‐phase entrainment spontaneously occur, characterized by cyclic movements proceeding simultaneously in the same (in‐phase) or opposite (anti‐phase) direction. Here we investigate corticospinal excitability during the observation of vertical oscillations of an index finger using Transcranial Magnetic Stimulation (TMS). Motor‐evoked potentials (MEPs) were recorded from participants’ flexor and extensor muscles of the right index finger, placed in either a maximal steady flexion or extension position, with stimulations delivered at maximal flexion, maximal extension or mid‐trajectory of the observed finger oscillations. Consistent with the occurrence of dynamical motor entrainment, increased and decreased MEP responses – suggesting the facilitation of stable in‐phase and anti‐phase relations but not an unstable 90° phase relation – were found in participants’ flexors. Anti‐phase motor facilitation contrasts with the activation of internal motor representation as it involves activity in the motor system opposite from activity required for the execution of the observed movement. These findings demonstrate the relevance of dynamical entrainment theories and methods for understanding spontaneous motor activity in the brain during action observation and the mechanisms underpinning coordinated movements during social interaction.  相似文献   
1000.
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