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101.
We present the case of a Japanese male infant with Alexander disease who developed infantile spasms at 8 months of age. The patient had a cluster of partial seizures at 4 months of age. He presented with mild general hypotonia and developmental delay. Macrocephaly was not observed. Brain magnetic resonance imaging (MRI) findings fulfilled all MRI-based criteria for the diagnosis of Alexander disease and revealed mild atrophy of the dorsal pons and medulla oblongata with abnormal intensities. DNA analysis disclosed a novel heterozygous missense mutation (c.1154 C>T, p.S385F) in the glial fibrillary acidic protein gene. At 8 months of age, tonic spasms occurred, and electroencephalography (EEG) revealed hypsarrhythmia. Lamotrigine effectively controlled the infantile spasms and improved the abnormal EEG findings. Although most patients with infantile Alexander disease have epilepsy, infantile spasms are rare. This comorbid condition may be associated with the distribution of the brain lesions and the age at onset of Alexander disease.  相似文献   
102.
Izumi Y  Tokuda K  Zorumski CF 《Hippocampus》2008,18(3):258-265
Low-level activation of N-methyl-d-aspartate receptors (NMDARs) results in a decrease in the ability of tetanic stimulation to induce long-term potentiation (LTP). This NMDAR-mediated LTP inhibition is observed with low micromolar concentrations of NMDA or chelation of ambient extracellular zinc. In rat hippocampal slices, we examined whether LTP inhibition by 1 muM NMDA and zinc chelation share common mechanisms. We found that both forms of LTP inhibition involve nitric oxide (NO) synthase (NOS) and calcineurin. Furthermore, both forms of LTP inhibition are overcome by block of p38 mitogen-activated protein kinase (MAPK), but not by inhibition of extracellular signal-regulated kinase 1/2 or c-Jun-N-terminal kinase. A p38 antagonist also overcame the block of LTP by sodium nitroprusside, an agent that releases NO, suggesting that NO release occurs upstream of MAPK activation. Despite the involvement of p38 MAPK in NMDAR-mediated LTP inhibition, p38 antagonism did not enhance LTP induction in response to weak tetanic stimulation under baseline conditions. These results indicate that p38 MAPK is part of a complex NMDAR-driven signaling pathway involving calcineurin and NO that helps to regulate synaptic plasticity in the CA1 region.  相似文献   
103.
BACKGROUND: Knowledge of the normal MRI appearances of the ankle ligaments and tendons is particularly important in the diagnosis of ankle sprains. In most clinical practices, the ankle is imaged in a neutral position with standard imaging planes and sequences. The purpose of our study was to investigate whether passive positioning influences the MRI appearances of the ligaments of the ankle. METHODS: The axial and coronal T1-weighted MR images obtained from 10 subjects were reviewed by two musculoskeletal radiologists. The following imaging planes were used: dorsiflexion with inversion, dorsiflexion with neutral, dorsiflexion with eversion, neutral with inversion, neutral, neutral with eversion, plantarflexion with inversion, plantarflexion with neutral, and plantarflexion with eversion. A subjective rating system was used to determine the optimal imaging plane and position for individual ligaments in each volunteer. Each ligament was rated on a scale (of 1 to 6). RESULTS: There were significant differences in the appearances of the anterior talofibular (p = 0.0002), calcaneofibular (p < 0.0001), and posterior talofibular (p < 0.0001) ligaments between the optimal and least optimal ankle positions in the axial plane, and in those of the (plantar calcaneonavicular) spring (p < 0.0001), tibiocalcaneal (p < 0.0001), posterior tibiotalar (p = 0.0087) and posterior talofibular (p = 0.0213) ligaments in the coronal plane. CONCLUSIONS: Kinematic MRI of the ankle is feasible and appears to improve visualization of ankle ligaments compared to MRI.  相似文献   
104.

Background

Immunoglobulin (Ig) A nephropathy (IgAN) is characterized by mesangial deposits of IgA1 and C3, often with co-deposits of IgG. We attempted to clarify the clinical significance of mesangial IgG deposition in patients with IgAN.

Methods

We retrospectively reviewed 57 patients who were diagnosed with IgAN on the basis of pathological examination of renal biopsy specimens obtained between October 2006 and December 2010. Subjects were divided into two groups: IgA+IgG deposition (IgA-IgG) group (n = 29) and IgA deposition alone (IgA) group (n = 28). The study outcome was complete remission (CR), defined as negative proteinuria by dipstick urinalysis and urinary erythrocytes of less than 1–4/high-power field.

Results

Proteinuria was greater in the IgA-IgG group than the IgA group (1.1 ± 0.8 vs. 0.7 ± 0.6 g/day, Mann–Whitney U test, P = 0.042). Capillary wall IgA deposits were noted more frequently in the IgA-IgG group than the IgA group (59 vs. 11 %, Fisher’s exact test, P = 0.014). During the median follow-up period of 33.3 months (range 6–55 months) in the 57 patients, we observed CR in 24 cases (42.1 %). After the start of treatment, urinary abnormalities disappeared earlier in the IgA group than in the IgA-IgG group (log rank test, P = 0.012). Cox’s regression model showed that IgG deposition reduced the hazard ratio for CR (hazard ratio 0.35; 95 % confidence interval 0.14–0.82, P = 0.014). Therefore, IgG deposition is a risk factor for persistent urinary abnormalities.

Conclusion

Mesangial IgG deposition is associated with more severe clinical features in patients with IgAN.  相似文献   
105.

Background

C1 lateral mass screw was widely used for fixation of the upper cervical spine. However, massive bleeding from the C1–2 venous plexus is sometimes encountered. In this study, we proposed an alternate method for C1 lateral mass screw insertion, which involves insertion of the screws caudally from the C2 nerve root to reduce bleeding from C1–2 venous plexus.

Methods

Seven patients with atlantoaxial lesions were included in this study. The mean age at surgery was 65.9 (34–82) years. The mean follow-up period was 23.1 (12–38) months. All patients underwent atlantoaxial fusion with C1 lateral mass screws, which were inserted caudally from the C2 nerve root. All screws were inserted using O-arm based navigation system. Operative time, blood loss, C2 nerve root injury and perioperative complications were investigated. The accuracy of C1 screws and bone union were evaluated using postoperative computed tomography.

Results

A total of 13 C1 lateral mass screws were inserted using this method. The mean operative time was 224 (144–305) min. The mean blood loss was 209 (100–357) g. One perioperative complication was observed, which was recurrent laryngeal nerve palsy. There were no vertebral artery or spinal cord injuries. No case of massive bleeding from the C1–2 venous plexus was observed. One patient complained of postoperative occipital neuralgia, which disappeared in 2 weeks. No malposition of C1 lateral mass screws was observed on postoperative computed tomography. Bone union was observed in all patients.

Conclusion

The C1 lateral mass screw insertion caudally from the C2 nerve root may become an alternate method for insertion of C1 screws.  相似文献   
106.

Background

Lumbar decompression surgery is often used to treat neurological symptoms of the lower extremity as a result of lumbar disease. However, this method also leads to the improvement of the accompanying low back pain (LBP). We studied the extent of LBP improvement after lumbar decompression surgery without fusion and the associated preoperative factors.

Methods

Patients (n = 140) with lumbar spinal stenosis (n = 90) or lumbar disc herniation (n = 50) were included. To evaluate the change in LBP, VAS scores and the Oswestry disability index scores were measured before surgery and 2 weeks, 3 months, and 6 months after surgery. The predictors of residual LBP were investigated using logistic regression analyses.

Results

In total, 140 patients were examined. The VAS scores for LBP before surgery and 2 weeks, 3 months, and 6 months after surgery were 4.4 ± 3.0 (mean ± standard deviation), 1.1 ± 1.5, 1.3 ± 1.8, and 1.9 ± 2.2, respectively. LBP significantly improved 2 weeks after surgery (P < 0.001), stabilized between 2 weeks and 3 months after surgery, but was significantly aggravated 3–6 months after surgery (P < 0.001). At 6 months after surgery, 67 (47.9%) patients had a VAS score of >1. The predictors of residual LBP included severe preoperative LBP, degenerative scoliosis and the size of the Cobb angle. The independent predictors, determined by multivariate analysis were degenerative scoliosis and the size of the Cobb angle.

Conclusions

LBP was alleviated at 2 weeks after lumbar decompression surgery for lumbar disc herniation and lumbar spinal stenosis. The predictors of residual LBP after decompression included more severe LBP at baseline, degenerative scoliosis and the size of Cobb angle.

Level of evidence

Level 3.  相似文献   
107.
108.
The c-erbB-2 product is thought to be a unique and useful target for antibody therapy of cancers overexpressing the c-erbB-2 gene. In vitro and in vivo anti-tumour effects of a humanised antibody against the extracellular domain of the c-erbB-2 gene product, rhu4D5, were examined. Rhu4D5 was less effective than its murine counterpart, mu4D5, for the direct antiproliferative activity against the c-erbB-2-overexpressing SK-BR-3 cell line. In vivo treatment of severe combined immunodeficient (SCID) mice carrying the c-erbB-2-overexpressing 4-1ST human gastric carcinoma xenograft with 4hu4D5 revealed that the recombinant protein had potent anti-tumour activity. Furthermore, cytotoxicity of human peripheral blood mononuclear cells against 4-1ST was significantly augmented with rhu4D5, but not with mu4D5. These results indicate that rhu4D5 might perform better in patients than predicted from preclinical studies.  相似文献   
109.
The structures of two novel 3,4-seco-lanostane-type triterpenes isolated from the sclerotium of Poria cocos were established to be 16alpha-hydroxy-3,4-seco-lanosta-4(28),8,24-triene-3,21-dioic acid (1; poricoic acid G) and 16alpha-hydroxy-3,4-seco-24-methyllanosta-4(28),8,24(24(1))-triene-3,21-dioic acid (2; poricoic acid H) on the basis of spectroscopic methods. These two, and eight other known compounds isolated from the sclerotium, poricoic acid B (3), poricoic acid A (4), tumulosic acid (5), dehydrotumulosic acid (6), 3-epidehydrotumulosic acid (7), polyporenic acid C (8), 25-hydroxy-3-epidehydrotumulosic acid (9), and dehydroabietic acid methyl ester (10), showed potent inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Evaluation of the cytotoxicity of compounds 1 and 4 against human cancer cell lines revealed that 1 was significantly cytotoxic to leukemia HL-60 cells [GI(50) (concentration that yields 50% growth) value 39.3 nM], although it showed only moderate cytotoxicity to the other cells. Compound 4 exhibited moderate cytotoxicity to all of the cancer cell lines tested.  相似文献   
110.
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