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11.
Chronic microvascular inflammation and oxidative stress are inter-related mechanisms underpinning white matter disease and vascular cognitive impairment (VCI). A proposed mediator is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2), a major source of reactive oxygen species (ROS) in the brain. To assess the role of Nox2 in VCI, we studied a tractable model with white matter pathology and cognitive impairment induced by bilateral carotid artery stenosis (BCAS). Mice with genetic deletion of Nox2 (Nox2 KO) were compared to wild-type (WT) following BCAS. Sustained BCAS over 12 weeks in WT mice induced Nox2 expression, indices of microvascular inflammation and oxidative damage, along with white matter pathology culminating in a marked cognitive impairment, which were all protected by Nox2 genetic deletion. Neurovascular coupling was impaired in WT mice post-BCAS and restored in Nox2 KO mice. Increased vascular expression of chemoattractant mediators, cell-adhesion molecules and endothelial activation factors in WT mice post-BCAS were ameliorated by Nox2 deficiency. The clinical relevance was confirmed by increased vascular Nox2 and indices of microvascular inflammation in human post-mortem subjects with cerebral vascular disease. Our results support Nox2 activity as a critical determinant of VCI, whose targeting may be of therapeutic benefit in cerebral vascular disease.  相似文献   
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Guit  GL; Shaw  PC; Ehrlich  J; Kroon  HM; Oudkerk  M 《Radiology》1985,154(2):305-306
A case of mixed connective tissue disease (MCTD) is presented in which mediastinal lymphadenopathy was the most prominent radiological finding detected by plain chest radiographs and computed tomography. Pulmonary arterial hypertension, which is a rare and often fatal complication of MCTD, also developed in this patient.  相似文献   
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Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
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High-dose (HD) cytosine arabinoside (ARA-C) is more effective treatment than conventional-dose ARA-C regimens for patients with relapsed acute nonlymphocytic leukemia (ANLL). We report here that HD ARA-C given during the first remission of ANLL has resulted in long remission durations and a high proportion of patients who survive more than three years free of disease. From August 1979 to September 1983, 36 adult patients with ANLL in first remission received one to three courses of HD ARA-C (3 g/m2 by one-hour infusion every 12 hours for 12 doses on days 1 through 6) alone or with daunorubicin (30 mg/m2 for two or three doses on days 7 through 9). Three patients died of sepsis or hemorrhage during consolidation, and 14 patients have relapsed from five to 48 months after diagnosis. The remaining 19 patients are in continued complete remission (CCR) from 11 to 62 months. Denoting all deaths in remission as relapse, the actuarial probability of CCR is 42% at 62 months, with an apparent plateau in the survival curve. Of the first 22 patients treated, ten remain in CCR from 37 to 62 months with no therapy for at least three years. Due to its heightened anti-leukemic activity, HD ARA-C allows brief but effective consolidation of ANLL in first remission, with long-term disease-free survival comparable to other approaches.  相似文献   
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PURPOSE: To evaluate how sutureless amniotic membrane patches may affect visual functions in normal human eyes. DESIGN: Prospective intervention study. METHODS: Ten sets of sutureless amniotic membrane patch manufactured as PROKERA were inserted in one eye of six normal patients. Four sets (one each) were inserted in four patients, while six sets (three each) were inserted in two patients. Uncorrected distant and near visual acuities, color vision, amniotic membrane thickness measured by pachymetry, and total symptom scores were compared before and after insertion. RESULTS: Within 30 minutes after insertion, mean distant visual acuities decreased from -0.22 +/- 0.06 to 0.92 +/- 0.45 logarithmic minimum angle of resolution (logMAR). Among 10 sets of PROKERA inserted, the largest optotype (1.0 logMAR) of the near vision chart could not be recognized in five, but color vision evaluated by Panel D-15 was still preserved in all. Total symptom scores increased to 47.8 +/- 9.1 points (maximum, 100 points). Among symptoms, total scores for foreign body sensation (17.8 +/- 3.6) and blurred vision (17.8 +/- 4.4) were high. Loss of distant visual acuity and increases of symptom scores were not correlated with amniotic membrane thickness, of which the mean was 67.6 +/- 25.2 mum. However, amniotic membrane that was less opaque tended to provide relatively good visual acuities. CONCLUSION: Because of the relative non-transparency of sutureless amniotic membrane patches in PROKERA, distant and near visual acuities decreased in normal human eyes. The foreign body sensation noted after insertion is primarily derived from the rigid supporting skirt.  相似文献   
17.
Patients with hairy cell leukemia (HCL) and chronic lymphocytic leukemia (CLL) were treated with recombinant interferon alpha A (rIFN- alpha A). The binding of iodinated recombinant interferon-alpha to baseline samples of peripheral blood mononuclear cells (PBMCs) from the leukemia patients was compared with clinical responsiveness to rIFN- alpha A. HCL patients (8/10) responded to rIFN-alpha A therapy, whereas none (0/10) of the CLL patients studied responded. The PBMCs from the eight responsive HCL patients bound approximately twice as much iodinated interferon as the PBMCs from nonresponsive CLL patients. This difference was due to more high-affinity receptors per cell with no difference in the affinity of the interferon-receptor interaction. However, because PBMCs from HCL patients were larger than PBMCs from CLL patients, the cell surface receptor density was similar. The leukemic cells from one of the two nonresponsive HCL patients bound iodinated interferon similarly to the cells from the responsive HCL patients, whereas the leukemic cells from the other nonresponsive HCL patient bound considerably less. The rapidity of response of the HCL patients did not correlate with the level of binding of iodinated interferon. Our results suggest that the absolute number of interferon receptors per cell may be only one of several important parameters in the response to rIFN-alpha A therapy, and that the responsiveness of a particular lymphoproliferative disease or a particular patient to rIFN- alpha A therapy cannot be predicted or explained solely by the degree of interaction between IFN and its cell surface receptor.  相似文献   
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Ion-channel gene defects are associated with a range of paroxysmal disorders, including several monogenic epilepsy syndromes. Two autosomal dominant disorders present in the first year of life: benign familial neonatal seizures, which is associated with potassium-channel gene defects; and benign familial infantile seizures, for which no genes have been identified. Here, we describe a clinically intermediate variant, benign familial neonatal-infantile seizures, with mutations in the sodium-channel subunit gene SCN2A. This clinico-molecular correlation defines a new benign familial epilepsy syndrome beginning in early infancy, an age at which seizure disorders frequently have a sombre prognosis.  相似文献   
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