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91.
Neural substrates for functionally discriminating self-face from personally familiar faces 总被引:5,自引:0,他引:5
Platek SM Loughead JW Gur RC Busch S Ruparel K Phend N Panyavin IS Langleben DD 《Human brain mapping》2006,27(2):91-98
Understanding the neurobiological substrates of self-recognition yields important insight into socially and clinically critical cognitive functions such as theory of mind. Experimental evidence suggests that right frontal and parietal lobes preferentially process self-referent information. Recognition of one's own face is an important parameter of self-recognition, but well-controlled experimental data on the brain substrates of self-face recognition is limited. The goal of this study was to characterize the activation specific to self-face in comparison with control conditions of two levels of familiarity: unknown unfamiliar face and the more stringent control of a personally familiar face. We studied 12 healthy volunteers who made "unknown," "familiar," and "self" judgments about photographs of three types of faces: six different novel faces, a personally familiar face (participant's fraternity brother), and their own face during an event-related functional MRI (fMRI) experiment. Contrasting unknown faces with baseline showed activation of the inferior occipital lobe, which supports previous findings suggesting the presence of a generalized face-processing area within the inferior occipital-temporal region. Activation in response to a familiar face, when contrasted with an unknown face, invoked insula, middle temporal, inferior parietal, and medial frontal lobe activation, which is consistent with an existing hypothesis suggesting familiar face recognition taps neural substrates that are different from those involved in general facial processing. Brain response to self-face, when contrasted with familiar face, revealed activation in the right superior frontal gyrus, medial frontal and inferior parietal lobes, and left middle temporal gyrus. The contrast familiar vs. self produced activation only in the anterior cingulate gyrus. Our results support the existence of a bilateral network for both perceptual and executive aspects of self-face processing that cannot be accounted for by a simple hemispheric dominance model. This network is similar to those implicated in social cognition, mirror neuron matching, and face-name matching. Our findings also show that some regions of the medial frontal and parietal lobes are specifically activated by familiar faces but not unknown or self-faces, indicating that these regions may serve as markers of face familiarity and that the differences between activation associated with self-face recognition and familiar face recognition are subtle and appear to be localized to lateral frontal, parietal, and temporal regions. 相似文献
92.
Navarro-Quiroga I Hernandez-Valdes M Lin SL Naegele JR 《The Journal of comparative neurology》2006,497(5):833-845
The rodent dentate gyrus (DG) is formed in the embryo when progenitor cells migrate from the dentate neuroepithelium to establish a germinal zone in the hilus and a secondary germinal matrix, near the fimbria, called the hippocampal subventricular zone (HSVZ). The developmental plasticity of progenitors within the HSVZ is not well understood. To delineate the migratory routes and fates of progenitors within this zone, we injected a replication-incompetent retrovirus, encoding the enhanced green fluorescent protein (EGFP), into the HSVZ of postnatal day 5 (P5) mice. Between P6 and P45, retrovirally-infected EGFP(+) of progenitors migrated into the DG, established a reservoir of progenitor cells, and differentiated into neurons and glia. By P6-7, EGFP(+) cells were observed migrating into the DG. Subsets of these EGFP(+) cells expressed Sox2 and Musashi-1, characteristic of neural stem cells. By P10, EGFP(+) cells assumed positions within the DG and expressed immature neuronal markers. By P20, many EGFP(+) cells expressed the homeobox prospero-like protein Prox1, an early and specific granule cell marker in the CNS, and extended mossy fiber projections into the CA3. A subset of non-neuronal EGFP(+) cells in the dentate gyrus acquired the morphology of astrocytes. Another subset included EGFP(+)/RIP(+) oligodendrocytes that migrated into the fimbria, corpus callosum, and cerebral cortex. Retroviral injections on P15 labeled very few cells, suggesting depletion of HSVZ progenitors by this age. These findings suggest that the early postnatal HSVZ progenitors are multipotent and migratory, and contribute to both dentate gyrus neurogenesis as well as forebrain gliogenesis. 相似文献
93.
PURPOSE: To evaluate the incidence of sexual dysfunction in men with focal epilepsy and to establish their hormonal profiles. METHODS: We prospectively analyzed sexual functions and hormone blood levels in 40 male patients (age ranged from 18 to 44 years, with an average age of 27.6+/-5.6 years) with refractory focal epilepsy. We used the Czech version of the structured questionnaire entitled International Inventory of Erectile Function (IIEF) to assess the patients' sexual functions. The subscales of this questionnaire separately evaluate erectile function (IIEF I), orgasmic function (IIEF II), sexual desire (IIEF III), intercourse satisfaction (IIEF IV), and overall satisfaction with sex life (IIEF V). In all of the patients, the following blood tests were performed: quantitative assessment of blood levels of prolactin (PRL), total testosterone (total-T), free androgen index (FAI), sexual hormone-binding globulin (SHBG), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS), progesterone (PRG), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). All these quantitative laboratory data were correlated with other clinical variables and with the results of the IIEF. chi2 and Wilcoxon tests were used for the statistical analysis. A p-value<0.05 was considered to be statistically significant. RESULTS: At least one of the types of sexual dysfunction, as defined by IIEF (IIEF I, II, and III), was found in 22 (55%) of the 40 patients (55%). Erectile dysfunction (IIEF I) was found in six (15%) of 40 patients, orgasmic dysfunction (IIEF II) in six (15%) of 40 patients, and loss of sexual desire (IIEF III) in 16 (40%) of 40 patients. According to other subscales of IIEF, 22 (55%) of 40 patients were not satisfied with sexual intercourse (IIEF IV), and 20 (50%) of 40 patients were not satisfied with their sex livee (IIEF V). None of the subscales of IIEF was significantly correlated with the age of the patients or with the duration of epilepsy. In patients with at least one of the sexual dysfunctions (IIEF I, II, and III), we found a statistically significant increase of FSH and SHBG, and a decrease of DHEAS and FAI in comparison with those in the patients with normal sexual functions. In patients with erectile dysfunction, we found the same changes and a significant increase of E2. In patients with orgasmic dysfunction, we found a statistically significant decrease of DHEAS. In patients with dysfunction of sexual desire, we noticed a significant increase of SHBG and a decrease of DHEAS and FAI. All patients with orgasmic dysfunction were being treated with carbamazepine (CBZ) in monotherapy or combination therapy. In patients with at least one type of sexual dysfunction (IIEF I, II, and III), we found a higher proportion of valproate treatment in monotherapy or combination therapy in comparison with CBZ. CONCLUSIONS: Our study showed a relatively high incidence of sexual dysfunction and dissatisfaction with sexual intercourse and sex life, as defined by the IIEF I-V questionnaire, in men with refractory focal epilepsy. The most frequent dysfunction in these patients is the impairment of sexual desire. However, our study indicates some specific hormonal changes related to various types of sexual dysfunction that are not related to antiepileptic drug treatment. 相似文献
94.
Roppolo D Ribaud V Jungo VP Lüscher C Rodriguez I 《The European journal of neuroscience》2006,23(11):2887-2894
In mammals, sensory neurons from the main olfactory and vomeronasal systems project their axons to the olfactory bulbs in the brain. We here report that a cluster of neurons, distinct from these two systems, located at the very tip of the mouse nose and called the Grüneberg ganglion expresses the mature olfactory-sensory neuron-specific marker olfactory marker protein (OMP), but is unlikely to express known odorant or pheromone receptors. The ganglion is present at birth and maintained during adult life. Tracing experiments indicate that these neurons target ipsilaterally to a specific set of glomeruli located on the caudal part of the olfactory bulb, and that this connection is necessary for the survival of the ganglion. The glomerular targets are structures previously proposed to be associated with suckling behaviour. These observations strongly suggest that this peculiar olfactory neuronal population plays a sensory role, possibly linked to chemoperception. 相似文献
95.
Dagmar Fojtiková Milan Brázdil Jaroslav Horky Michal Mikl Robert Kuba Petr Krupa Ivan Rektor 《Seizure》2006,15(7):533-540
PURPOSE: To investigate possible neuronal dysfunction of the thalamus in patients suffering from typical absence epilepsy, using magnetic resonance spectroscopy (MRS). Special attention was paid to levels of N-acetylaspartate (NAA) and creatine (Cr), and to the NAA/Cr ratio. METHODS: MRS was performed over the right and left thalamus in nine patients suffering from typical absence epilepsy, and in nine sex- and age-matched healthy controls. All patients and controls were examined using a standard MRS-CSI (chemical shift imaging) technique. RESULTS: Statistical analysis of the obtained data demonstrated a significantly lower thalamic NAA/Cr ratio in patients with typical absence epilepsy when compared to the healthy controls. Our MRS data showed symmetrical distribution of NAA/Cr ratio in the right and left thalamus within both the patient group and the group of healthy controls. No significant correlation between the patients' thalamic NAA/Cr values and the duration of the epilepsy or seizure frequency was revealed. CONCLUSIONS: The present MRS data clearly indicate neuronal dysfunction in the thalami of patients with typical absence epilepsy. In agreement with other recent MRS findings in different idiopathic generalized epilepsy syndromes, our results confirm the role of the thalamus as an important structure in the pathogenesis of typical absence epilepsy. 相似文献
96.
Aortic dissection during pregnancy is a potentially catastrophic clinical condition and can be lethal to both mother and fetus. The treatment of aortic dissection in pregnancy is based on location, severity, and gestational age. We report a case of acute aortic dissection in a 30-year-old female patient in her 26th week of gestation. Ascending aorta resection and interposition of a 26-mm Dacron graft was carried out without circulatory arrest by means of a double-felt "sandwich" technique on both anastomoses. The patient was discharged from the hospital 10 days after her initial admission. At the 34th week of gestation, the patient delivered a healthy baby by cesarean section. Because our patient was hemodynamically unstable, our aim at the 26th week of gestation was to perform a simplified surgical procedure, to avoid circulatory arrest, and to maintain a high perfusion pressure, in order to save the patient's life and to decrease the potential risk of damage to the fetus. 相似文献
97.
Bing Wang Guohua Lü Youwen Deng Weidong Liu Jing Li Ivan Cheng 《European spine journal》2011,20(9):1526-1532
Anterior decompression and/or reconstruction can be an effective method for the surgical treatment of ventral spinal cord
compression in the upper cervical spine. Options for traditional surgical approaches include transoral, transnasal, and extraoral.
The risk and complex anatomy with the aforementioned approaches induces surgeons to use the transcervical route to expose
the upper cervical spine. A traditional transcervical approach, however, carries the disadvantages of a deep operative field
and steep trajectory. We performed a new endoscopically assisted method of anterior reconstruction for the treatment of ventral
lesions in upper cervical spine. Six patients were treated from January 2005 to December 2007. Among those six patients, three
patients were diagnosed with fixed atlantoaxial dislocations, two with plasmacytomas, and one with a giant cell tumor. All
patients were treated by combined endoscopically assisted anterior reconstruction and posterior fusion. One patient with a
fixed atlantoaxial dislocation sustained a cerebrospinal fluid leak in the immediate postoperative period, which spontaneously
resolved 7 days after surgery. None of the patients had any neurologic deterioration following surgery, nor did any require
admission to the intensive care unit for any reason. At the final follow-up, all patients were found to have evidence of a
successful clinical outcomes and radiographic fusion. There were no implant failures or radiographic signs of implant migration
or loosening. In conclusion, this study demonstrates that an anterior transcervical decompression using endoscopic visualization
combined with a posterior arthodesis can achieve good clinical and radiographic outcomes. 相似文献
98.
Vulev I Klepanec A Madaric J Tomka J Sefranek V 《Annals of vascular surgery》2011,25(8):1140-1140.e16
Vascular complications after lumbar laminectomy are rare, but are potentially life-threatening. A 59-year-old man presented with progressive and worsening abdominal pain over several weeks. Multidetector computed tomography angiography revealed a large aorto-ostial left renal artery pseudoaneurysm 3 years after lumbar laminectomy. The pseudoaneurysm was successfully treated with a combination of various endovascular techniques ("jailed" microcatheter technique, stent-graft implantation, thrombin injection, balloon remodeling technique, Onyx application), with preserved patency of the left renal artery and pseudoaneurysm exclusion on 6-month follow-up multidetector computed tomography angiography. The size and location of this pseudoaneurysm and the combination of different techniques for endovascular treatment provides an update on current endovascular technology. Combination of different endovascular techniques can be a safe and feasible alternative for the treatment of complicated iatrogenic postlaminectomy vascular injuries and renal artery pseudoaneurysms. 相似文献
99.
Pohlemann T Stengel D Tosounidis G Reilmann H Stuby F Stöckle U Seekamp A Schmal H Thannheimer A Holmenschlager F Gänsslen A Rommens PM Fuchs T Baumgärtel F Marintschev I Krischak G Wunder S Tscherne H Culemann U 《Injury》2011,42(10):997-1002
Study objective
To determine longitudinal trends in mortality, and the contribution of specific injury characteristics and treatment modalities to the risk of a fatal outcome after severe and complex pelvic trauma.Methods
We studied 5048 patients with pelvic ring fractures enrolled in the German Pelvic Trauma Registry Initiative between 1991 and 1993, 1998 and 2000, and 2004 and 2006. Complete datasets were available for 5014 cases, including 508 complex injuries, defined as unstable fractures with severe peri-pelvic soft tissue and organ laceration. Multivariable mixed-effects logistic regression analysis was employed to evaluate the impact of demographic, injury- and treatment-associated variables on all-cause in-hospital mortality.Results
All-cause in-hospital mortality declined from 8% (39/466) in 1991 to 5% (33/638) in 2006. Controlling for age, Injury Severity Score, pelvic vessel injury, the need for emergency laparotomy, and application of a pelvic clamp, the odds ratio (OR) per annum was 0.94 (95% confidence interval [CI] 0.91–0.96). However, the risk of death did not decrease significantly in patients with complex injuries (OR 0.98, 95% CI 0.93–1.03). Raw mortality associated with this type of injury was 18% (95% CI 9–32%) in 2006.Conclusion
In contrast to an overall decline in trauma mortality, complex pelvic ring injuries remain associated with a significant risk of death. Awareness of this potentially life-threatening condition should be increased amongst trauma care professionals, and early management protocols need to be implemented to improve the survival prognosis. 相似文献100.
Rakovac I Tudor A Sestan B Prpic T Gulan G Madarevic T Santic V Ruzic L 《International orthopaedics》2011,35(10):1523-1528