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81.
82.
Immunoglobulin (Ig) E and IgG anti-thyroid autoantibodies (AAbs) play important roles in the immunopathogenesis of chronic spontaneous urticaria (CSU). To date, association of IgE and IgG AAbs with Chinese CSU patients has not been fully investigated. We aimed to explore prevalence rates of IgE and IgG AAbs in Chinese CSU patients and their association with clinical and laboratory parameters. Serum IgE and IgG AAbs against thyroid peroxidase (TPO) and thyroglobulin (TG), total IgE (tIgE) and specific IgEs were measured using enzyme-linked immunosorbent assay, chemiluminescence microparticle immunoassay and immunoblotting. Meta-analyses and literature review were conducted. The meta-analyses indicated that CSU cases were 4.98, 6.90 and 6.68 times more likely to have positive anti-TPO IgE, anti-TPO IgG and anti-TG IgG (all P < 0.001) compared with controls, respectively, and revealed a positive correlation between the prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.53, P = 0.025). A total of 1,100 Chinese Han adult CSU patients and 1,100 ethnicity-, age- and sex-matched healthy controls were recruited from 15 centers. Prevalence rates of anti-TPO IgE, anti-TPO IgG, anti-TG IgE or anti-TG IgG in the patients were all significantly higher than those in the controls. Significant correlations were observed between prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.297, P < 0.001) as well as between those of anti-TG IgE and anti-TG IgG in the patients (r = 0.137, P < 0.001). Patients with anti-TPO IgE or anti-TPO IgG had significantly lower tIgE levels (P < 0.001). Positive anti-TPO IgE, positive anti-TPO IgG and tIgE < 40 IU/mL were independent predictors of antihistamine-refractory cases. In conclusion, the prevalence rates of IgE and IgG AAbs in Chinese CSU patients are significantly elevated and reciprocally correlated. This study verifies the results of previous case-control studies of CSU patients from other populations and ethnicities.  相似文献   
83.
The oculomotor organization of two elasmobranch species, smooth dogfish (Mustelus canis) and little skate (Raja erinacea), was studied by investigating the extraocular muscle apparatus and the oculomotor motoneuron distribution. The macroscopic appearance of the eye muscles was similar to any lateral-eyed vertebrate species (e.g., goldfish, rabbit). The size of extraocular muscles was expressed by counting single muscle fibers and comparing cross-sectional areas of the extraocular muscles. There were significant differences in the number of fibers in the six extraocular muscles in dogfish, but not in skate. Fiber sizes varied considerably; thus, the number of fibers did not relate to cross-sectional areas. In the dogfish, no one pair of agonist-antagonist extraocular muscles was larger than the others, suggesting that there was no preference for eye movements in a particular plane of space. However, the lateral rectus was more than twice the size of most of the other muscles. In the skate, cross-sectional areas of the horizontal eye muscles were smaller than those of the vertical eye movers. This may indicate a reduced utilization of horizontal eye muscles, which may reflect the bottom-dwelling habitat and mode of locomotion of the skate. The distribution of the extraocular motoneurons was determined by injecting horseradish peroxidase (HRP) into single eye muscles. Medial rectus, superior rectus, and superior oblique motoneuron populations were located contralateral to their respective muscles. Lateral rectus, inferior rectus, and inferior oblique motoneurons were located ipsilateral to their muscles. This distribution is in contrast to almost all other vertebrates studied thus far, where medial rectus motoneurons are located ipsilateral to the muscle which they innervate. The oculomotor arrangement in elasmobranchs is likely to have consequences for the circuitry responsible for the production of conjugate compensatory eye movements in the horizontal plane. We hypothesize that, in contrast to other vertebrates, the basic elasmobranch vestibulo-ocular reflex pathway consists of three identically structured three-neuron-arcs connecting the three semicircular canals to their respective extraocular muscles. This innervation pattern may constitute a special feature of the elasmobranch brain or a phylogenetically older arrangement of eye movement pathways.  相似文献   
84.
Intracranial trajectories of sympathetic nerve fibers originating in the superior cervical ganglion (SCG) in the rat were investigated by means of anterograde labeling following the injection of wheat germ agglutinin-horseradish peroxidase conjugate (WGA-HRP) into the unilateral SCG. The trajectory of the sympathetic fiber innervating the pineal gland and its continuing structures was found advancing along the abducent nerve, through the cavernous plexus, then along the trochlear nerve. Labeled sympathetic fibers showed two patterns of distribution in the blood vessels on the basal surface of the brain. The sympathetic fibers originating in the unilateral SCG were intermingled with those fibers from the contralateral SCG in the pineal gland, its continuing structures and the choroid plexus of the third ventricle as well as in the cerebral blood vessels.  相似文献   
85.
Pyramidal tract (PT) or corticopontine neurons of the cat somatosensory cortex (SI) were identified with antidromic activation on stimulation of the bulbar pyramid or pontine nuclei (PN) and stained intracellularly with HRP after examining the electrophysiological properties. Comparison of the conduction velocity of the stem axons and the soma-dendritic morphology revealed that in the cat SI, there exists two types of layer V pyramidal neurons, i.e. one has smooth apical dendrites with larger soma (51.6 +/- 9.5 x 22.7 +/- 2.8 micron) and the other has richly spinous apical dendrites with smaller soma (34.0 +/- 8.8 x 15.3 +/- 3.3 micron). The former group responded antidromically at latencies shorter than 1 ms by PT stimulation or 1.5 ms by PN stimulation, respectively. These values were consistent with the borderline latencies between two similar groups of layer V pyramidal neurons in the motor (fast and slow PTNs) and parietal (aspiny and spiny layer V corticopontine neurons) cortices in the cat.  相似文献   
86.
The spatial organization of olfactory nerve projections   总被引:1,自引:0,他引:1  
The spatial organization of olfactory nerve projections was examined in the rat. The pathway was traced by orthograde transport of HRP following nasal lavage and by retrograde transport of HRP following injections into the olfactory bulb. The results indicated that there was a broad relationship between the epithelium and the olfactory bulb. Specific regions of the olfactory bulb received input from a large region of the epithelium. However, there was evidence that olfactory nerve terminations were not uniformly dense across their terminal fields. The results suggest that there may be finer sorting of olfactory nerves based on functional specificity.  相似文献   
87.
The hypothalamus is known to be intimately involved in the control of autonomic function. This study provides detailed information about pathways between the hypothalamus and the dorsal vagal complex in cat. Injection of horseradish peroxidase into the dorsomedial medulla produced retrograde neuronal labeling in the paraventricular nucleus of the hypothalamus. Injection of 3H-leucine into the paraventricular nucleus produced dense anterograde labeling in the dorsal motor nucleus of the vagus, and lighter labeling in the nucleus of the tractus solitarius, particularly in its medial subnucleus. The subnucleus gelatinous was virtually free of label, except in its medial and lateral portions. Anterograde labeling was distributed bilaterally, with an ipsilateral predominance. Injection of horseradish peroxidase into the area of the paraventricular nucleus produced retrograde neuronal labeling bilaterally in the nucleus of the tractus solitarius and the reticular formation ventrolateral to the dorsal vagal complex. anterograde terminal labeling overlapped the distribution of retrogradely labeled neurons. These findings are compared to those in rat, and discussed in relation to their functional implications.  相似文献   
88.
Our horseradish peroxidase retrograde tracing study revealed a specific subpopulation of ventral tegmental area (VTA) neurons that send axons to the occipital cortex in the rat. A fluorescent retrograde tracing study demonstrated that neuronal populations in the VTA projecting to the occipital cortex are distributed in a manner separate from those projecting to forebrain structures such as the frontal/anterior cingulate cortices and nucleus accumbens. The scarcity of collateral projections from the VTA contrasts with the extensive collateralization of projection neurons in the substantia nigra pars compacta. Projections to the occipital cortex may define the distribution of cells comprising the VTA and thus the clear hodological separation of the A9 and A10 dopamine cell groups.  相似文献   
89.
Glutaric Aciduria type I (GA-I) is caused by mutations in the GCDH gene. Its deficiency results in accumulation of the key metabolites glutaric acid (GA) and 3-hydroxyglutaric acid (3-OHGA) in body tissues and fluids. Present knowledge on the neuropathogenesis of GA-I suggests that GA and 3-OHGA have toxic properties on the developing brain.We analyzed morphological and biochemical features of 3D brain cell aggregates issued from Gcdh?/? mice at two different developmental stages, day-in-vitro (DIV) 8 and 14, corresponding to the neonatal period and early childhood. We also induced a metabolic stress by exposing the aggregates to 10 mM l-lysine (Lys).Significant amounts of GA and 3-OHGA were detected in Gcdh?/? aggregates and their culture media. Ammonium was significantly increased in culture media of Gcdh?/? aggregates at the early developmental stage. Concentrations of GA, 3-OHGA and ammonium increased significantly after exposure to Lys. Gcdh?/? aggregates manifested morphological alterations of all brain cell types at DIV 8 while at DIV 14 they were only visible after exposure to Lys. Several chemokine levels were significantly decreased in culture media of Gcdh?/? aggregates at DIV 14 and after exposure to Lys at DIV 8.This new in vitro model for brain damage in GA-I mimics well in vivo conditions. As seen previously in WT aggregates exposed to 3-OHGA, we confirmed a significant ammonium production by immature Gcdh?/? brain cells. We described for the first time a decrease of chemokines in Gcdh?/? culture media which might contribute to brain cell injury in GA-I.  相似文献   
90.
高脂血症,脂质过氧化,抗氧化酶活性与动脉粥样硬化的关系   总被引:27,自引:0,他引:27  
用大剂量胆固醇(1.5g/日)喂家兔60天后停胆固醇30天塑造动脉粥样硬化(AS)模型。观察血胆固醇、过氧化脂(LPO)含量和抗氧化酶活性与AS病变发生发展的关系。发现:血清胆固醇水平随喂胆固醇时间延长而升高,至60天时达高峰,停饲胆固醇,血清胆固醇水平迅速下降,而同样升高的LPO水平不但未降,反而继续升高,明显高于对照的水平。抗氧化酶SOD和GSH-Px活性在LPO升高的早期显示代偿性增高,以后即降低并保持在低于对照的水平。主动脉、肺动脉和冠状动脉均发生程度不等的AS病变,即使在停饲胆固醇一个月后亦可见进行性病变,如大量平滑肌细胞增生和炎细胞浸润,且其病变较前更重。以上结果提示,血中过量的LPO抑制了抗氧化酶活性,可能在AS的发生发展中起重要作用。  相似文献   
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