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91.
Susac syndrome.     
OBJECTIVE: The objective of this study was to describe the clinical manifestations; radiographic, audiometric, and retinal fluorescein angiography findings; pathogenesis and treatment of Susac syndrome with review of the literature. STUDY DESIGN: We conducted a retrospective case review. SETTING: This study was conducted at a tertiary referral center. PATIENT: A 50-year-old woman presented with recurrent episodes of neurologic symptoms, bilateral sensorineural hearing loss, and silent retinal artery occlusion. INTERVENTIONS: The patient underwent complete evaluation, including magnetic resonance image studies, audiometric tests, and retinal fluorescein angiography. She was treated initially with corticosteroids and later with other immunosuppressive agents. RESULTS: The patient was initially diagnosed with left sudden sensorineural hearing loss. Despite comprehensive clinical and laboratory studies that did not reveal systemic disease, 3 weeks later, the patient developed vertigo, sensorineural hearing loss, and tinnitus in the opposite ear. The neurologic involvement and the bilateral audiologic manifestations raised the possibility of Susac syndrome. CONCLUSION: Susac syndrome is a rare disorder of unknown origin characterized by the triad of encephalopathy, fluctuating hearing loss, and visual loss resulting from microangiopathy of the brain, cochlea, and retina. The multiple organ involvement seen in Susac syndrome raises a differential diagnosis ranging from autoimmune disease, through systemic vasculitis, to multiple sclerosis. Otolaryngologists should be aware of this syndrome as a result of the vestibulocochlear manifestations and the multidisciplinary evaluation that is required.  相似文献   
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We describe a novel form of myopathy in a mother and her two daughters from an inbred Samaritan family. The patients displayed severe neonatal hypotonia, lethargy and dysmorphic features. Motor milestones were delayed; however, the hypotonia and muscle weakness gradually improved during the first 2 years of life and independent walking was achieved by 18 months. The mother at the age of 23 years shows myopathic facies and minimal proximal weakness. Her intelligence is normal. Her muscle biopsy revealed central nuclei and disruption of the intermyofibrillary network with moth eaten and spiral fibers. Mutations in SMN, MTM1 and the myotonic dystrophy genes were excluded. We suggest this is a new benign form of congenital myopathy. Inheritance is probably autosomal recessive.  相似文献   
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A recent study has suggested that a dodecamer duplication in the HOPA gene in Xq13 may occur in a significant portion of male patients with autism. We have determined the incidence of this duplication in 202 patients from the South Carolina Autism Study. The incidence of the duplication was not significantly different between patients and controls. Three of the female patients inherited the duplication from nonautistic fathers. In addition, there was no systematic skewing of X inactivation in the female patients with the duplication, or in nonautistic mothers and sisters with the duplication. These findings suggest that the dodecamer duplication in the HOPA gene does not play a significant role in the etiology of autism.  相似文献   
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PURPOSE: In biopsies of patients with locally advanced breast cancer, we investigated the in vivo changes of the gene expression pattern induced by chemotherapy to find genes that are potentially responsible for the efficacy of the drug. EXPERIMENTAL DESIGN: Early cellular responses to chemotherapy-induced damage, both in vivo and in vitro, were investigated by analyzing chemotherapy-induced changes in gene expression profiles. Core biopsies were taken from nine patients with locally advanced breast cancer, before and at 6 hours after initiation of doxorubicin-based chemotherapy. Both samples were cohybridized on the same microarray containing 18,000 cDNA spots. RESULTS: The analysis revealed marked differences in gene expression profile between treated and untreated samples. The gene which was most frequently found to be differentially expressed was p53 up-regulated modulator of apoptosis (PUMA). This gene was up-regulated in eight of nine patients with an average factor of 1.80 (range, 1.36-2.73). In vitro MCF-7 breast cancer cells exposed to clinically achievable doxorubicin concentrations for 6 hours revealed marked induction of PUMA mRNA, as well. CONCLUSIONS: This is the first report describing PUMA mRNA to be up-regulated as a response to chemotherapy in patients. Because PUMA is a known member of the family of BH3-only proapoptotic proteins, this finding suggests PUMA's potential importance for the response to anticancer drugs.  相似文献   
95.
PURPOSE: Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer. PATIENTS AND METHODS: Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m(2) orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8. RESULTS: Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment. CONCLUSION: The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points.  相似文献   
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Background: Loneliness is a common problem in adolescence. Earlier research focused on genes within the serotonin and oxytocin systems, but no studies have examined the role of dopamine‐related genes in loneliness. In the present study, we focused on the dopamine D2 receptor gene (DRD2). Methods: Associations among the DRD2, sex, parental support, and loneliness were examined in a longitudinal study spanning five annual waves (N = 307). Results: Using Latent Growth Curve Modeling, DRD2 genotype was not directly related to loneliness. Interactions were found between parental support and DRD2 genotype, showing that adolescents with the A2A2 genotype who perceived little support from their parents had the highest baseline levels of loneliness. Adolescents with an A1 allele were not susceptible to the rewarding effect of parental support. Conclusions: The present study is the first to examine the role of the DRD2 genotype in loneliness. Our results contribute to a further understanding of the environmental and genetic basis of loneliness in adolescence.  相似文献   
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