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101.
Myotonic dystrophy type 1 (DM1) is a multisystemic disorder affecting, among others, the endocrine system, with derangement of steroid hormones functions. Vitamin D is a steroid recognized for its role in calcium homeostasis. In addition, vitamin D influences muscle metabolism by genomic and non-genomic actions, including stimulation of the insulin-like-growth-factor 1 (IGF1), a major regulator of muscle trophism. To verify the presence of vitamin D deficit in DM1 and its possible consequences, serum 25-hydroxyvitamin D (25(OH)D), calcium, parathormone (PTH), and IGF1 levels were measured in 32 DM1 patients and in 32 age-matched controls. Bone mineral density (BMD) and proximal muscle strength were also measured by DXA and a handheld dynamometer, respectively. In DM1 patients, 25(OH)D levels were reduced compared to controls, and a significant decrease of IGF1 was also found. 25(OH)D levels inversely correlated with CTG expansion size, while IGF1 levels and muscle strength directly correlated with levels of 25(OH)D lower than 20 and 10 ng/ml, respectively. A significantly higher percentage of DM1 patients presented hyperparathyroidism as compared to controls. Calcium levels and BMD were comparable between the two groups. Oral administration of cholecalciferol in 11 DM1 patients with severe vitamin D deficiency induced a normal increase of circulating 25(OH)D, ruling out defects in intestinal absorption or hepatic hydroxylation. DM1 patients show a reduction of circulating 25(OH)D, which correlates with genotype and may influence IGF1 levels and proximal muscle strength. Oral supplementation with vitamin D should be considered in DM1 and might mitigate muscle weakness.  相似文献   
102.
Tourette syndrome is a neurodevelopmental disorder characterized by multiple tics and is often associated with comorbid behavioral problems. Research with generic instruments in child populations showed that comorbid disorders can have a greater impact on health-related quality of life than tic severity. This study investigated the usefulness of a newly developed disease-specific instrument, the Gilles de la Tourette Syndrome–Quality of Life Scale for Children and Adolescents (GTS-QOL-C&A), in assessing health-related quality of life in young patients with Tourette syndrome with and without behavioral comorbidity. We recruited 75 patients with Tourette syndrome (60 males; age 12.4 ± 3.2 years). All participants were evaluated by a neuropsychiatrist and completed a standardized psychometric battery, including the GTS-QOL-C&A, Child Depression Inventory, and Multidimensional Anxiety Scale for Children. Forty-two patients (56%) fulfilled diagnostic criteria for at least one comorbidity: obsessive-compulsive disorder (n = 25 patients [33.3%]); attention deficit/hyperactivity disorder (n = 6 patients [8%]); both (n = 11 patients [14.7%]). The GTS-QOL-C&A demonstrated usefulness in differentiating “pure” Tourette syndrome from Tourette syndrome “plus” behavioral problems with regard to health-related quality of life scores for the obsessive-compulsive subscale. In addition to focusing on core tic symptoms, the GTS-QOL-C&A showed sensitivity to the impact of behavioral comorbidities on health-related quality of life and can usefully complement existing nonspecific instruments.  相似文献   
103.
We studied how nicotinic acetylcholine receptors (nAChRs) regulate glutamate release in the secondary motor area (Fr2) of the dorsomedial murine prefrontal cortex, in the presence of steady agonist levels. Fr2 mediates response to behavioral situations that require immediate attention and is a candidate for generating seizures in the frontal epilepsies caused by mutant nAChRs. Morphological analysis showed a peculiar chemoarchitecture and laminar distribution of pyramidal cells and interneurons. Tonic application of 5 µM nicotine on Layer V pyramidal neurons strongly increased the frequency of spontaneous glutamatergic excitatory postsynaptic currents. The effect was inhibited by 1 µM dihydro‐β‐erythroidine (which blocks α4‐containing nAChRs) but not by 10 nM methyllicaconitine (which blocks α7‐containing receptors). Excitatory postsynaptic currents s were also stimulated by 5‐iodo‐3‐[2(S)‐azetidinylmethoxy]pyridine, selective for β2‐containing receptors, in a dihydro‐β‐erythroidine ‐sensitive way. We next studied the association of α4 with different populations of glutamatergic terminals, by using as markers the vesicular glutamate transporter type (VGLUT) 1 for corticocortical synapses and VGLUT2 for thalamocortical projecting fibers. Immunoblots showed higher expression of α4 in Fr2, as compared with the somatosensory cortex. Immunofluorescence showed intense VGLUT1 staining throughout the cortical layers, whereas VGLUT2 immunoreactivity displayed a more distinct laminar distribution. In Layer V, colocalization of α4 nAChR subunit with both VGLUT1 and VGLUT2 was considerably stronger in Fr2 than in somatosensory cortex. Thus, in Fr2, α4β2 nAChRs are expressed in both intrinsic and extrinsic glutamatergic terminals and give a major contribution to control glutamate release in Layer V, in the presence of tonic agonist levels. Synapse 00:000–000, 2013 . © 2013 Wiley Periodicals, Inc.  相似文献   
104.
Neurodegeneration of the striatum in Huntington disease (HD) is characterized by loss of medium‐spiny neurons, huntingtin nuclear inclusions, reactive gliosis, and iron accumulation. Neuroimaging allows in vivo detection of the macro‐ and micro‐structural changes that occur from presymptomatic stages of the disease (preHD). The aim of our study was to evaluate the reliability of multimodal imaging as an in vivo biomarker of vulnerability and development of the disease and to characterize macro‐ and micro‐structural changes in subcortical nuclei in HD. Macrostructure (T1‐weighted images), microstructure (diffusion tensor imaging), and iron content (R relaxometry) of subcortical nuclei and medial temporal lobe structures were evaluated by a 3 T scanner in 17 preHD carriers, 12 early‐stage patients and 29 matched controls. We observed a volume reduction and microstructural changes in the basal ganglia (caudate, putamen, and globus pallidus) and iron accumulation in the globus pallidus in both preHD and symptomatic subjects; all these features were significantly more pronounced in patients, in whom degeneration extended to the other subcortical nuclei (i.e., thalamus and accumbens). Mean diffusivity (MD) was the most powerful predictor in models explaining more than 50% of the variability in HD development in the caudate, putamen, and thalamus. These findings suggest that the measurement of MD may further enhance the well‐known predictive value of striatal volume to assess disease progression as it is highly sensitive to tissue microimpairment. Multimodal imaging may detect brain changes even in preHD stages. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
105.

Introduction

In renal cell carcinoma (RCC), lymph node status at preoperative imaging is affected by a non-negligible false-positive rate. We aimed to investigate which factors are related to a concordance between clinical suspicion and pathological confirmation of lymph node invasion (LNI).

Methods

At a single tertiary care institution, 2954 RCC patients underwent either partial or radical nephrectomy. For the aim of the study, only clinically positive lymph node cases were included (cN1). Statistical analyses assessed the concordance between preoperative and pathological nodal status.

Results

Preoperative axial CT scans revealed 424 (14.4 %) patients showing at least one enlarged lymph node suspected for LNI (cN1). All lymphadenopathies were removed at surgery, and LNI was pathologically confirmed (pN1) in 122 patients (28.8 %). When focusing the analyses on clinical characteristics (variables known before surgery), metastases at diagnosis [OR 3.0 (95 %1.9–4.8), p < 0.001] and tumor size [OR 1.1 (95 % 1.1–1.2), p < 0.001] were the two most informative predictors of concordance between clinical and pathological nodal status. Concordance was also more likely in patients with papillary type II tumors (55.6 %) relative to papillary type I (38.1 %), clear cell (27.7 %) and chromophobe (8.3 %) tumors. At multivariable analyses, none of the considered blood markers resulted to be independently associated with LNI.

Conclusions

Roughly 70 % of patients showing a suspected lymph node preoperatively do not show LNI at the final pathological report. Among patients with clinically positive nodes, clinical tumor size and metastases at diagnosis represent the most informative and independent predictors of confirmed LNI at final pathology.
  相似文献   
106.
107.
Testicular cancer (TC) is the most common solid cancer in men between the third and fourth decade of life. Due to successful treatment approaches, TC survivors (TCSs) have long life expectancy, but with numerous potential long-term sequelae, including sexual dysfunction. We investigated predictors of long-term normal sexual function (SF) recovery in TCSs. Sociodemographic, medical, and psychometric data were analyzed in 143 Caucasian-European TCSs, who underwent orchiectomy at a single institution. Health-significant comorbidities were scored with the Charlson Comorbidity Index (CCI). Patients completed the International Index of Erectile Function (IIEF). Statistical models tested the association between predictors (including age at surgery, body mass index, CCI, and adjuvant therapy: radiotherapy [RT], chemotherapy [CT], CT followed by retroperitoneal lymph node dissection [RPLND] and RPLND alone) and the long-term recovery of normal SF (defined as IIEF-erectile function [EF] ≥26, and sexual desire [SD], intercourse satisfaction [IS] orgasmic function [OF], and overall satisfaction [OS] domain scores in the upper tertiles). At a mean follow-up of 86 months, 35 (25.5%) TCSs had erectile dysfunction (ED), with 16 (11.2%) experiencing severe ED. Median time of EF recovery was 60, 60, and 70 months after CT, RT, and RPLND, respectively. Only adjuvant RT emerged as an independent predictor of nonrecovery of normal EF (HR: 0.55, P= 0.01). Neither adjuvant CT nor CT plus RPLND or RPLND alone significantly impaired the recovery of normal erections. Adjuvant therapy was not associated with impaired recovery of normal sexuality as a whole, considering the IIEF-SD, -OF, -IS, and OS domains.  相似文献   
108.
The aim of the present study was to investigate whether foetal hand movements are planned and how they are executed. We performed a kinematic analysis of hand movements directed towards the mouth and the eyes in the foetuses of eight women with normally evolving pregnancies. At 14, 18 and 22 weeks of gestation, eight foetuses underwent a 20-min four-dimensional-ultrasound session. The video recordings for these movements were then imported into in-house software developed to perform kinematic analysis. We found that spatial and temporal characteristics of foetal movements are by no means uncoordinated or unpatterned. By 22 weeks of gestation the movements seem to show the recognizable form of intentional actions, with kinematic patterns that depend on the goal of the action, suggesting a surprisingly advanced level of motor planning.  相似文献   
109.
110.
The selection of objects in the visual environment is important in everyday life when acting in a goal-directed manner. Here we used functional magnetic resonance imaging (fMRI) to investigate brain activity while healthy subjects (N=15) selectively reached to grasp a three-dimensional (3D) target stimulus presented either in isolation or in the presence of 3D non-target stimuli. A pneumatic MRI compatible apparatus was designed to precisely control the presentation of 3D graspable stimuli within the scanner. During scanning subjects were instructed to reach and grasp towards a target presented at an unknown location either in isolation or flanked by two distractor objects. Results indicated that reaching towards and grasping the target object in the presence of other non-target stimuli was associated with greater activation within the contralateral primary motor cortex and the precuneus as compared to the execution of reach-to-grasp movements towards the target presented in isolation. We conclude that the presence of non-targets evokes a differential level of neural activity within areas responsible for the planning and execution of selective reach-to-grasp movement.  相似文献   
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