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321.
Only a handful of the hundreds of known vertebrate retroviruses have been deliberately subverted for use as carriers of recombinant genetic material. Retroviruses receive their name from the fact that their genome undergoes conversion from RNA to DNA following infection of a host cell. Also characteristic of retroviruses and uncommon for most other types of viruses is that the genome of the retrovirus integrates itself permanently into the DNA of the host cell. Once integrated into the host genome, the inserted provirus acts as a factory for producing more retroviral RNA genomes and expressing retroviral packaging proteins. Both components combine to form viral particles that bud from the surface of the infected cells.  相似文献   
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BACKGROUND & AIMS: Systemic glucocorticosteroids (GCSs) have proven efficacy in active ulcerative colitis but cause undesired systemic side effects. Therefore, new GCSs with high topical activity and a high rate of metabolism may be of clinical value in this condition. The aim of this study was to explore the efficacy and safety of the topically acting GCS budesonide in an oral controlled-release formulation in extensive or left-sided, mild to moderately active ulcerative colitis. METHODS: A 9-week, randomized, double-blind, controlled trial was performed, and treatments with 10 mg budesonide or 40 mg prednisolone daily, both gradually tapered, were compared. Endoscopic improvement and effect on endogenous plasma cortisol were assessed. RESULTS: Thirty- four patients were administered budesonide, and 38 patients were administered prednisolone. Mean endoscopic scores improved significantly in both groups but without difference between the groups. Five patients in the budesonide group and 7 patients in the prednisolone group deteriorated and were withdrawn from the study. Morning plasma cortisol levels were suppressed in the prednisolone group (entry, 449 nmol/L; 2 weeks, 116 nmol/L; 4 weeks, 195 nmol/L) but were unchanged in the budesonide group. CONCLUSIONS: The GCS budesonide administered in an oral controlled-release formulation seems to give an overall treatment result in active ulcerative colitis approaching that of prednisolone but without suppression of plasma cortisol levels. This concept merits further evaluation. (Gastroenterology 1996 Jun;110(6):1713-8)  相似文献   
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Disease progression in amyotrophic lateral sclerosis (ALS) is characterized by degeneration of motoneurons (MN) and their axons, but is also influenced by neighboring cells such as astrocytes and microglial cells. The role of microglia in ALS is complex as it switches from an anti‐inflammatory and neuroprotective phenotype in early disease to a proinflammatory and neurotoxic phenotype in later stages. Our previous studies in models of neurodegeneration identified rho kinase (ROCK) as a target, which can be manipulated to beneficially influence disease progression. Here, we examined the neuroprotective potential of the ROCK inhibitor Fasudil to target the central pathogenic features of ALS. Application of Fasudil to kainic acid‐lesioned primary MN in vitro resulted in a strong prosurvival effect. In vivo, SOD1G93A mice benefited from oral treatment with Fasudil showing prolonged survival and improved motor function. These findings were correlated to an improved survival of motor neurons and a pronounced alteration of astroglial and microglial cell infiltration of the spinal cord under Fasudil treatment. Modeling a proinflammatory microglial phenotype by stimulation with LPS in vitro, Fasudil decreased the release of proinflammatory cytokines and chemokines TNFα, Il6, CCL2, CCL3, and CCL5 while CXCL1 release was only transiently suppressed. In sciatic nerve motor axons, neuromuscular junction remodeling processes were increased. In conclusion, we provide preclinical and neurobiological evidence that inhibition of ROCK by the clinically approved small molecule inhibitor Fasudil may be a novel therapeutic approach in ALS combining both neuroprotection and immunomodulation for the cure of this devastating disease. GLIA 2014;62:217–232  相似文献   
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BACKGROUND: Familial amyloidotic polyneuropathy (FAP) is a hereditary systemic amyloidosis with cardiac involvement. As early identification of the cardiac involvement is of major clinical interest we performed this study to test the hypothesis that tissue Doppler imaging (TDI) and strain imaging (SI) might disclose cardiac involvement in patients with early stages of FAP. METHODS: Twenty-two patients with FAP and 36 healthy controls were studied. Standard M-mode and Doppler echocardiography were performed. TDI and SI were used to assess the regional longitudinal left ventricular (LV) lateral and septal and right ventricular (RV) wall functions. All time intervals were corrected for heart rate by dividing with R-R interval and presented as percentage. RESULTS: We found that patients in comparison with controls had increased LV and RV wall thickness and by using TDI a prolonged isovolumic relaxation time (IVRt) at the septal segment (15.0+/-7.0 vs 10.7+/-4.1%, p<0.05) and prolonged isovolumic contraction time (IVCt) at LV lateral (12.8+/-4.3 vs 10.1+/-3.3%, p<0.05), septal (12.5+/-3.5 vs 8.9+/-1.9%, p<0.001) and RV free wall segments (12.0+/-3.6 vs 8.3+/-2.1%, p<0.001). Strain was reduced at LV lateral basal segment (-4.6+/-14.0 vs -20.2+9.1, p<0.001), RV free wall mid segment (-16.2+/-12.8 vs -29.4+/-15.2) as well as both septal segments (-4.1+/-11.7 vs -16.2+/-9.0%, p<0.001, -8.8+/-11.5 vs -19.4+/-8.4%, p<0.001 for septal basal and mid-segment). Even in the absence of septal hypertrophy the septal strain was reduced and the regional IVCt was prolonged. CONCLUSIONS: This is the first clinical study using TDI and strain in patients with FAP showing functional abnormalities before any morphological echocardiographic abnormalities were present. Both the left and right heart functions are involved and the disease should therefore be regarded as biventricular.  相似文献   
328.
Heart complications are frequently encountered in hereditary transthyretin amyloidosis. Lately, reports of late onset familial amyloid polyneuropathy (FAP) cases presenting with a phenotype similar to that observed in senile systemic amyloidosis have emerged. The aim of the present study was to evaluate morphological and functional features of the heart by echocardiography including myocardial strain measurements, and to compare the outcome for early with those of late onset FAP cases. Eighty-one biopsy and genetically proven FAP, ATTR Val30Met patients were investigated with two-dimensional, M-mode echocardiography and myocardial strain with special attention to inter-ventricular septum (IVS) thickness. IVS thickness was closely related to the age at onset (P < 0.0001), but not to duration of disease. Seventeen percent of the patients had severe left ventricular hypertrophy (IVS > 15 mm). These patients were all late onset cases and represented 39% of all of the late onset cases. Strain measurements were also closely related to IVS thickness and age at onset thereby signifying a decreased function of the heart muscle in late onset cases. From the present investigation it appears that late onset Swedish FAP-cases more readily develop cardiomyopathy with an increased IVS thickness. Different pathways for amyloid formation in the heart may operate in early and late onset cases.  相似文献   
329.
Familial amyloidotic polyneuropathy (FAP) designates TTR mutations where the phenotype is dominated by a peripheral sensory-motor polyneuropathy. The most common mutation is ATTR Val30Met. FAP in association with ATTR Phe33Leu has been described previously in two American families, one of Polish-Lithuanian descent and the other of Polish-American. In this study, we report the phenotype of the ATTR Phe33Leu in a Swedish family. The proband is a 48 year-old patient from northern Sweden, whose father died with symptoms suggestive of FAP. Characteristic clinical features included polyneuropathy, carpal tunnel syndrome and asymptomatic, but echocardiographic examination diagnosed cardiomyopathy. The family history supports an early intervention with orthotopic liver transplantation in patients with FAP associated with the TTR Phe33Leu, and the patient was submitted for liver transplantation.  相似文献   
330.
We report two new amyloidogenic transthyretin (TTR) variants detected in the Swedish population. One variant was previously unknown, while the other has been described in a French family. In Swedish patients, both variants have caused late-onset cardiac amyloidosis characterised by heart failure. In both cases, the diagnosis was determined by the detection of amyloid deposits in skin and/or rectal biopsies and identification of TTR mutations by genetic analysis. The index case of the previously unknown mutation (ATTR His88Arg) was a 66-year-old Swedish man, who sought medical attention for increasing dyspnea. Echocardiographic examination disclosed a restrictive cardiomyopathy, and subsequent examinations disclosed TTR amyloidosis. The patient is alive with moderate symptoms one year after the onset of disease. The index case for the new Swedish mutation (ATTR Gly53Glu) is a woman who sought medical attention at the age of 57 because of increasing dyspnea. Echocardiographic examination disclosed a hypertrophic cardiomyopathy with diastolic impairment. The diagnosis of systemic amyloidosis was made by fat aspiration biopsy and histopathology. The patient developed severe intractable heart failure, with pulmonary effusion and ascites. She died four years after the onset of her disease of intractable heart and kidney failure. Post mortem examination of biopsy specimens and blood revealed TTR amyloid deposits and the ATTR Gly53Glu mutation was detected.  相似文献   
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