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81.
This study examined if children with cryptogenic epilepsy and complex partial seizures (CPS) have smaller total brain, frontal, and temporal lobe volumes than normal children and how this is related to seizure, cognitive, psychiatric, and demographic variables. Forty-four children with CPS and 38 normal children, aged 5-16 years, underwent brain MRI scans at 1.5 T. Tissue was segmented, and total brain, frontal lobe, frontal parcellation, and temporal lobe volumes were computed. Other than significantly larger temporal lobe white matter volumes in the CPS group, there were no significant differences in brain volumes between the CPS and normal groups. Earlier onset, longer duration of illness, younger chronological age, and presence of a psychiatric diagnosis were significantly related to smaller frontotemporal volumes in subjects with CPS. Although these findings suggest that CPS might affect development of the temporal and frontal regions, we are unable to rule out the possibility that smaller frontotemporal volumes might predispose children to CPS. These findings highlight the need to control for seizure, cognitive, psychiatric, and demographic variables in studies of frontotemporal volumes in pediatric CPS.  相似文献   
82.
Semaphorins and their receptors, plexins, have emerged as key regulators of various aspects of neuronal development. In contrast to the Plexin-A family, the cellular functions of Plexin-B family proteins in developing neurons are only poorly understood. An activation of Plexin-B1 via its ligand, semaphorin 4D (Sema4D), produces an acute collapse of axonal growth cones in hippocampal and retinal neurons over the early stages of neurite outgrowth. However, the functional role of Sema4D-Plexin-B interactions over subsequent stages of neurite development, differentiation and maturation has not been characterized. Here we addressed this question using morphogenetic assays and time-lapse imaging on developing rat hippocampal neurons as a model system. Interestingly, Sema4D treatment over several hours was observed to promote branching and complexity in hippocampal neurons via the activation of Plexin-B1. The activation of receptor tyrosine kinases and the Rho kinase following Sema4D treatment was found to control dendritic and axonal morphogenesis by differentially regulating branching and extension. Phosphoinositide-3-kinase, but not extracellular signal-regulated kinase 1/2, was observed to be important for the stimulatory effects of Sema4D on dendritic branching. Furthermore, we observed that the mammalian target of rapamycin is activated downstream of Plexin-B1 and contributes to Sema4D-induced effects on dendritic branching. In contrast, glycogen synthase kinase-3 beta, another effector of phosphoinositide-3-kinase signalling, was not involved. Thus, our results show that Sema4D-Plexin-B interactions modulate dendritic and axonal arborizations of developing neurons by co-ordinated and concerted activation of diverse signalling pathways.  相似文献   
83.
Purpose:   This study examined the severity and range of linguistic impairments in young, intermediate, and adolescent youth with epilepsy and how these deficits were associated with illness effects, nonverbal intelligence, psychopathology, and reading.
Methods:   Tests of language, intelligence, achievement, and structured psychiatric interviews were administered to 182 epilepsy youth, aged 6.3–8.1, 9.1–11.7, and 13.0–15.2 years, as well as to 102 age- and gender-matched normal children. Parents provided demographic, seizure-related, and behavioral information on their children.
Results:   Significantly more epilepsy subjects had language scores 1 standard deviation (SD) below average than the age-matched control groups did. The intermediate and adolescent epilepsy groups also had significantly lower mean language scores compared to their matched controls. The older compared to the younger epilepsy groups had more language impairment and a wider range of linguistic deficits. Longer duration of illness, childhood absence epilepsy, psychiatric diagnosis, and socioeconomic status were associated with linguistic deficits in the young group. Prolonged seizures, lower Performance IQ, and minority status predicted low language scores in the intermediate epilepsy group. In the adolescent group, language impairment was associated with poor seizure control, decreased Performance IQ, and lower socioeconomic status. Linguistic and reading deficits were significantly related in each epilepsy group.
Conclusions:   The age-related increase in linguistic impairment, different profiles of predictors in each age group, and the relationship of linguistic deficits with poor reading skills have important clinical, developmental, theoretical, and academic implications.  相似文献   
84.
Atypical patterns of metastatic spread from colorectal primary tumors are often misdiagnosed, with potential implications for the clinical outcome. Metastatic diffusion to the splanchnocranium is extremely rare in colorectal cancer. A histological proof of diagnosis is rarely obtained and therapeutic management is a challenge. We describe the case of a 46-year-old patient who presented with a radiologically proven sphenoid wing metastasis. The patient presented with left-sided exophthalmos while receiving systemic chemotherapy for relapsed high-risk colorectal cancer. A left sphenoid wing metastasis was proven by a head computed tomography scan. A metastatic spread to the sino-nasal tract is regarded as a poor prognosis determinant in colorectal cancer and presents a unique set of diagnostic and therapeutic challenges. The compression of noble structures such as the optic nerve holds serious implications in terms of quality of life but there is insufficient evidence clarifying whether radiotherapy or surgery represent the best option for these patients, leaving the therapeutic plan to be decided case by case.  相似文献   
85.
86.
Grasspea (Lathyrus sativus), because of its low cost and ease of cultivation, is often an adulterant of other legumes. The seeds—albeit rich in protein (~20–32% of dry seed weight)—contain a neurotoxin, 3-N-oxalyl-l-2,3-diaminopropanoic acid (β-ODAP). An efficient and sensitive RP-HPLC method for detecting β-ODAP by pre-column derivatisation with O-phthalaldehyde (OPA) was developed in our laboratory. The usefulness of this method for measuring the β-ODAP content of thermally processed legume-based foods with various substitution levels of grasspea flour is demonstrated. The β-ODAP content of dehulled grasspea flour used was 5.26 ± 0.11 mg/g. The method shows a clear resolution between β-ODAP and its non-toxic α-isomer. At 1% (w/w) substitution it was possible to detect and distinguish the two isomers. Among the unit heat operations deep-frying results in the β-ODAP content being lowered by ~80% irrespective of the substitution level. The decrease in β-ODAP content by fermentation was ~58%, which was further decreased on steaming. The results indicate that levels as low as 0.01 mg of β-ODAP/g of product are measurable. Therefore this method is a useful tool in detecting the unwarranted use of grasspea flour in processed foods that pose health risks to unsuspecting customers.  相似文献   
87.
88.
OBJECTIVE: The objective of this study was to evaluate the efficacy of paroxetine in treating major depressive disorder (MDD) in persons with multiple sclerosis (MS). METHOD: In this double-blind trial, 42 participants with MS and MDD were randomly assigned to one of two parallel 12-week treatment arms: paroxetine or placebo. The participants started at an initial dose of 10 mg/day paroxetine or placebo, titrated up to 40 mg daily based on symptoms response and side effects. The primary outcome measure was the Hamilton Rating Scale for Depression (HAM-D). Secondary outcomes included fatigue, anxiety and self-reported quality of life. RESULTS: Intent-to-treat analyses revealed that both groups improved from pretreatment to posttreatment. Although the treatment group improved more than the control group on most measures, few differences were statistically significant. For the primary outcome, 57.1% of participants in the treatment arm had at least a 50% reduction in HAM-D score, compared with 40% in the control group (nonsignificant). Treatment effects were greater among the participants who completed the study; 78.6% of completers had a treatment response compared with 42.1% of controls (P=.073). CONCLUSION: Although paroxetine may not be efficacious for all persons with MS and MDD, it appears to benefit some individuals.  相似文献   
89.
Cellular-level anatomical data from early fetal brain are sparse yet critical to the understanding of neurodevelopmental disorders. We characterize the organization of the human cerebral cortex between 13 and 15 gestational weeks using high-resolution whole-brain histological data sets complimented with multimodal imaging. We observed the heretofore underrecognized, reproducible presence of infolds on the mesial surface of the cerebral hemispheres. Of note at this stage, when most of the cerebrum is occupied by lateral ventricles and the corpus callosum is incompletely developed, we postulate that these mesial infolds represent the primordial stage of cingulate, callosal, and calcarine sulci, features of mesial cortical development. Our observations are based on the multimodal approach and further include histological three-dimensional reconstruction that highlights the importance of the plane of sectioning. We describe the laminar organization of the developing cortical mantle, including these infolds from the marginal to ventricular zone, with Nissl, hematoxylin and eosin, and glial fibrillary acidic protein (GFAP) immunohistochemistry. Despite the absence of major sulci on the dorsal surface, the boundaries among the orbital, frontal, parietal, and occipital cortex were very well demarcated, primarily by the cytoarchitecture differences in the organization of the subplate (SP) and intermediate zone (IZ) in these locations. The parietal region has the thickest cortical plate (CP), SP, and IZ, whereas the orbital region shows the thinnest CP and reveals an extra cell-sparse layer above the bilaminar SP. The subcortical structures show intensely GFAP-immunolabeled soma, absent in the cerebral mantle. Our findings establish a normative neurodevelopment baseline at the early stage.  相似文献   
90.
Schmidtko A  Luo C  Gao W  Geisslinger G  Kuner R  Tegeder I 《Pain》2008,139(3):632-643
The synaptic vesicle protein synapsin II is specifically expressed in synaptic terminals of primary afferent nociceptive neurons and regulates transmitter release in the spinal cord dorsal horn. Here, we assessed its role in nerve injury-evoked molecular and behavioral adaptations in models of peripheral neuropathic pain using mice genetically lacking synapsin II. Deficiency of synapsin II resulted in reduced mechanical and cold allodynia in two models of peripheral neuropathic pain. This was associated with decreased glutamate release in the dorsal horn of the spinal cord upon sciatic nerve injury or capsaicin application onto the sciatic nerve and reduced calcium signals in spinal cord slices upon persistent activation of primary afferents. In addition, the expression of the vesicular glutamate transporters, VGLUT1 and VGLUT2, was strongly reduced in synapsin II knockout mice in the spinal cord. Conversely, synapsin II knockout mice showed a stronger and longer-lasting increase of GABA in lamina II of the dorsal horn after nerve injury than wild type mice. These results suggest that synapsin II is involved in the regulation of glutamate and GABA release in the spinal cord after nerve injury, and that a imbalance between glutamatergic and GABAergic synaptic transmission contributes to the manifestation of neuropathic pain.  相似文献   
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