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Cationic block copolymers spontaneously assemble via electrostatic interactions with DNA molecules in aqueous solution giving rise to micellar structures that protect the DNA from enzymatic degradation both in vitro and in vivo. In addition, we have previously shown that they are safe, not immunogenic and greatly increased antigen-specific CTL responses following six intramuscular inoculations of a very low dose (1 μg) of the vaccine DNA as compared to naked DNA. Nevertheless, they failed to elicit detectable humoral responses against the antigen. To gain further insight in the potential application of this technology, here we show that a shorter immunization protocol based on two DNA intramuscular inoculations of 1 μg of DNA delivered by these copolymers and a protein boost elicits in mice broad (both humoral and cellular) and long-lasting responses and increases the antigen-specific Th1-type T cell responses and CTLs as compared to priming with naked DNA. These results indicate that cationic block copolymers represent a promising adjuvant and delivery technology for DNA vaccination strategies aimed at combating intracellular pathogens.  相似文献   
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Parkinson's disease (PD) occurs worldwide, but little is known about PD in Africa. We systematically reviewed publications on PD in Africa, with emphasis on epidemiologic and genetic studies. Articles published between 1944 and December 2004 were identified using several strategies. The studies emanated from 13 African countries (Kenya, Uganda, Tanzania, Ethiopia, Nigeria, Senegal, Ghana, Togo, Libya, Tunisia, Algeria, Zimbabwe, and South Africa). The publications fell into four categories: clinical series (n = 17), prevalence studies (n = 7), incidence studies (n = 1), and genetic studies (n = 3). The clinical series documented the occurrence of PD in Africa and described its clinical characteristics. The prevalence studies suggested some intracontinental geographic variation in PD prevalence. Overall, the prevalence figures and the incidence rates of PD in Africa appeared lower than those reported for European and North American populations. Few genetic studies of PD have been reported from Africa, and none in blacks. There are no case-control or cohort studies of PD reported from Africa. This review provides a summary of PD research in Africa over the past 60 years and highlights the information gaps and potential areas for future research.  相似文献   
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We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
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The aim of the study was to evaluate the applicability to urine samples of the AmplifiedMycobacterium tuberculosis Direct Detection Test (AMTD), which is currently used to identify this organism in respiratory specimens within a few hours. The study was performed on 95 patients, comprising 35 subjects with a high index of suspicion for active tuberculosis of the urinary tract and 60 subjects with evidence of non-mycobacterial disease. One urine specimen from each subject was examined by microscopy, culture and AMTD. AMTD was positive in 38 specimens and negative in 57. Assuming culture as the reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 91.93%, 86.84% and 100%, respectively. Reassessing the discrepancies between AMTD and culture by review of patients' charts, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 93.44%, 89.47% and 100%. The results of the study as well as the characteristics of AMTD encourage its use for the rapid recognition of urinary tract tuberculosis, although its findings should be interpreted cautiously when the clinical picture is not consistent with an active tuberculosis.  相似文献   
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We report a case of cervical dystonia occurring in a 33-year-old without personal history of movement disorder but with family history of essential tremor, primigravid, primiparous woman at 1 weeks' amenorrhea, resolved completely after delivery in the course of 3 months. Dystonia never recurred in the following 5 years. Several neurological disorders are known to occur or worsen during pregnancy. As far as we know, this is the second reported case of dystonia occurring during pregnancy, thus confirming that dystonia gravidarum represents a new entity and should be considered in women of reproductive age affected by dystonia, especially when presenting with rapid-onset cervical dystonia.  相似文献   
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S100A1 is a calcium-binding protein, which has been recently found in renal cell neoplasms. We evaluated the diagnostic utility of immunohistochemical detection of S100A1 in 164 renal cell neoplasms. Forty-one clear cell, 32 papillary, and 51 chromophobe renal cell carcinomas, and 40 oncocytomas, 164 samples of normal renal parenchyma adjacent to the tumors and 13 fetal kidneys were analyzed. The levels of S100A1 mRNA detected by quantitative RT-PCR analysis of frozen tissues from seven clear cell, five papillary, and six chromophobe renal cell carcinomas, four oncocytomas, and nine samples of normal renal tissues adjacent to neoplasms were compared with the immunohistochemical detection of protein expression. Clear cell and papillary renal cell carcinomas showed positive reactions for S100A1 in 30 out of 41 tumors (73%) and in 30 out of 32 (94%) tumors, respectively. Thirty-seven renal oncocytomas out of 40 (93%) were positive for S100A1, whereas 48 of 51 (94%) chromophobe renal cell carcinomas were negative. S100A1 protein was detected in all samples of unaffected and fetal kidneys. S100A1 mRNA was detected by RT-PCR in all normal kidneys and renal cell neoplasms, although at very different levels. Statistical analyses comparing the different expression of S100A1 in clear cell and chromophobe renal cell carcinomas observed by immunohistochemical and RT-PCR methods showed significant values (P<0.001), such as when comparing by both techniques the different levels of S100A1 expression in chromophobe renal cell carcinomas and oncocytomas (P<0.001). Our study shows that S100A1 protein is expressed in oncocytomas, clear cell and papillary renal cell carcinomas but not in chromophobe renal cell carcinomas. Its immunodetection is potentially useful for the differential diagnosis between chromophobe renal cell carcinoma and oncocytoma. Further, S100A1 protein expression is constantly detected in the normal parenchyma of the adult and fetal kidney.  相似文献   
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