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231.
Hereditary spastic paraplegia (HSP) is a degenerative neurologic disorder that causes progressive, often severe, spastic weakness in the legs. Autosomal dominant HSP is a highly penetrant, genetically heterogeneous disorder with loci present on chromosomes 2p21-24, 2q24-34, 8q23-24, 10q23.3-24, 12q13, 14q12-23, 15q11-14 and 19q13.1. We identified a large HSP kindred in which the disorder was tightly linked to chromosome 14q12-23. We tested chorionic villus DNA samples of two at-risk fetuses for inheritance of microsatellite polymorphisms flanking and within this locus that segregated with the disease in this family. Whereas samples from the first fetus showed inheritance of a haplotype segregating with the disease allele (indicating high risk of developing HSP), samples from the second fetus showed inheritance of a haplotype segregating with the normal allele (indicating low risk of developing HSP). This is the first report of prenatal testing for HSP. Published in 2001 by John Wiley & Sons, Ltd.  相似文献   
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Background:

There are a few published studies about prognostic markers of Epstein-B virus (EBV) related to outcomes in pediatric Hodgkin Lymphoma (HL).

Objectives:

We aimed to investigate the prognostic value and effect of EBV on survival by using biopsy materials in children and adolescents diagnosed with HL.

Patients and Methods:

EBV LMP-1 expression was examined using immunohistochemical methods in 58 tumor samples. Clinical features, overall survival (OS) and failure free survival time (FFS) were compared between EBV LMP-1 positive and negative patients.

Results:

In 20 (35%) patients tumors were LMP-1 positive. When compared with patients above 10 years old, EBV LMP-1 was often positive in patients under 10 years old (30% vs. 70%, P = 0.02). In our most cases having B symptoms and advanced stage, EBV positiveness in Hodgkin Reed-Stenberg cells (H-RS) was not a significant determinant for survival (P = 0.78). Half of the past clinical trials in childhood HL reported longer survival rates in EBV LMP-1 positive patients. In some trials similar to our results there was no significant relationship between EBV and prognosis.

Conclusions:

The reason of diminished EBV positiviness may be related to technical methods such as not using immunohistochemical and in situ hybridization for EBER antigen but in laboratory conditions painting of control tissues with EBV impair this probability. In addition, cases enrolled to our study were living in Istanbul where social and economical factors are improved rather than generally.  相似文献   
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Objectives

Our aim was to compare three different definitions of treatment failure and discuss their use as quality outcome measures for a clinical service.

Methods

Data for treatment‐naïve patients who attended the Melbourne Sexual Health Centre (MSHC) between 1 January 2000 and 31 December 2008 were analysed. Definition 1 was the strict Food and Drug Administration (FDA) definition of treatment failure as determined using the time to loss of virological response (TLOVR) algorithm. Definition 2 defined treatment failure as occurring in those whose viral load never fell to <400 HIV‐1 RNA copies/mL or who developed two consecutive viral loads ≥400 copies/mL on any treatment (switching or stopping treatment with a viral load <400 copies/mL was permitted). Definition 3 was the same as definition 2 except that individuals were also deemed to have failed if they stopped treatment for 6 months or longer.

Results

There were 310 antiretroviral‐naïve patients who started treatment in the study period. Of these, 156 [50.3%; 95% confidence interval (CI) 42.1–53.3%] experienced treatment failure under definition 1, 10 (3.2%; 95% CI 1.5–5.8%) experienced treatment failure under definition 2, and 16 (4.5%; 95% CI 2.5–7.4%) experienced treatment failure under definition 3 over the 108 months of follow‐up. The probability of failing definition 1 was statistically different from the probability of failing definition 2 or 3 (P=0.01).

Conclusion

There were significant differences in treatment failure for the three definitions. If definition 1 were used, the outcomes would be sufficiently common to enable clinics to be compared but would be less meaningful. If definition 2 or 3 were used, the events would be too rare to enable clinics to be compared, but it would be possible to set a benchmark level of success that clinics could aim to reach.  相似文献   
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Background and the purpose of the study

Microemulsions are thermodynamically stable, clear dispersions of water, oil, surfactant, and cosurfactant. This study was aimed to develop flurbiprofen microemulsion for enhanced transdermal delivery and investigate the effects of different surfactants and cosurfactants on its delivery and phase behavior.

Method

Various surfactant-cosurfactant mixtures in ratio of 2:1 (Smix) along with oleic acid (oil) were selected and phase diagrams were constructed. Six microemulsions each containing 5% drug, 5% oil, 56% Smix and 34% water, were prepared and compared for their permeation and phase behaviors to determine the effects of the type of Smix.

Results

In vitro transdermal permeation through rabbit skin of all microemulsions was high than saturated aqueous drug solution. Tween 20 and ethanol as Smix produced the highest flux amongst all the Smix, and were used to prepare formulations with different values of oil and Smix. While the type of surfactant did not affect the droplet size, propylene glycol as cosurfactant produced the largest droplets and highest viscosity. Decrease in oil or Smix concentration resulted in decrease of the droplet size and increase in permeation flux while decrease in viscosity also increased the permeation flux of microemulsions. Finally the selected microemulsion formulation comprising 5% flurbiprofen, 5% oleic acid, 46% Tween 20:ethanol (2:1) and 44% water, showed the highest transdermal flux and caused no skin irritation.

Conclusion

Type of surfactant and cosurfactant affect both the phase behavior and transdermal drug delivery of microemulsion; and results of this study showed that they are promising vehicles for improved transdermal delivery and sustained action of flurbiprofen.  相似文献   
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Inflammatory myofibroblastic tumors (IMTs), otherwise known as the inflammatory pseudotumor, is a rare solid mesenchymal tumor, simulating malignant neoplasms, histologically characterized by the proliferation of spindle cells in a fibrous myxoid stroma containing inflammatory cells. CT and MR imaging are the most used tools in their assessment. Clinical features are nonspecific and depend on the localization of the tumor, radiologic findings are polymorphic and no-conclusive and present a diagnostic challenge to the radiologist. Although histology remains obligatory for the final diagnosis. Heren, we report a case of splenic IMT with histological correlation.  相似文献   
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