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991.
In 1942, Jaffe and Lichtenstein introduced the term aneurysmal bone cyst (ABC). Primary ABC is characterized by the presence of spongy or multi-cameral cystic tissue filled with blood. The process is benign, but it is locally destructive and has a high propensity for recurrence. In this paper, we present the third case of multiple metachronous primary ABCs as a rare variant of ABC. We describe the 10-year history of a 12-year-old boy with metachronous multiple primary ABCs at five different sites (right proximal humerus, right ulna, bilateral distal radius and right lateral clavicle). Furthermore, our patient suffered from vascular malformations, such as aortic isthmus stenosis, hypoplastic thoraco-abdominal aorta and bilateral renal artery stenosis. To date, in contrast to solitary ABC, the multiple lesions have been found more frequently in male individuals. Using interphase cytogenetics, we analyzed three of five of the patients ABCs and one of these was also analyzed by GTG-banding. No chromosomal abnormalities were found. Significantly, we excluded the missense mutation of codon 201 in guanine nucleotide-binding protein 1 gene consistently found in McCune-Albright syndrome (MAS) and in non-MAS cases of polyostotic fibrous dysplasia of bone with or without secondary ABC.  相似文献   
992.
Antigen presentation by major histocompatibility complex type II (MHC II) molecules and activation of CD4+ helper T cells are critical for the generation of immunological memory. We previously described a DNA vaccine encoding human immunodeficiency virus-1 p55Gag as a chimera with the lysosome-associated membrane protein (LAMP/gag). The LAMP/gag chimera protein traffics to the MHC II compartment of transfected cells and elicits enhanced immune responses as compared to a DNA vaccine encoding native gag not targeted to the MHC II compartment. We have now investigated the long-term responses of immunized mice and show that the LAMP/gag DNA vaccine promotes long-lasting B cell- and CD4+ and CD8+ T-cell memory responses induced by DNA encoding non-targeted Gag decay rapidly and elicit very low or undetectable levels of gag DNA is sufficient to generate T-cell memory. Following this initial priming immunization with LAMP/gag DNA, booster immunizations with native gag DNA or the LAMP/gag chimera are equally efficient in eliciting B- and T-cell secondary responses, results in accordance with observations that secondary expansion of CD8+ cells in the boost phase does not require additional CD4+ help. These findings underscore the significance of targeting DNA-encoded vaccine antigens to the MHC II processing compartments for induction of long-term immunological memory.  相似文献   
993.
994.
BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size.  相似文献   
995.
RNA interference is a powerful tool for studying gene function and for drug target discovery in diverse organisms and cell types. In mammalian systems, small interfering RNAs (siRNAs), or DNA plasmids expressing these siRNAs, have been used to down-modulate gene expression. However, inefficient transfection protocols, in particular, for primary cell types, have hampered the use of these tools in disease-relevant cellular assays. To be able to use this technology for genome-wide function screening, a more robust transduction protocol, resulting in a longer duration of the knock-down effect, is required. Here, we describe the validation of adenoviral vectors that express hairpin RNAs that are further processed to siRNAs. Infection of cell lines, or primary human cells, with these viruses leads to an efficient, sequence-specific, and prolonged reduction of the corresponding target mRNA, resulting in a reduction of the encoded protein level in the cell. For knock-down of one of the targets, GalphaS, we have measured inhibition of ligand-dependent, G-protein-coupled signaling. It is expected that this technology will prove to be of great value in target validation and target discovery efforts.  相似文献   
996.
997.
The facultatively intracellular pathogen Brucella, characterized by its capacity to replicate in professional and non professional phagocytes, also causes abortion in ruminants. This property has been linked to the presence of erythritol in the placenta, as brucellae preferentially utilize erythritol. The ery operon encodes enzymes involved in erythritol metabolism, and a link with virulence has since been discussed. Allelic exchange mutants in eryC of Brucella suis were erythritol sensitive in vitro with a MIC of 1 to 5 mM of erythritol. Their multiplication in macrophage-like cells was 50- to 90-fold reduced, but complementation of the mutant restored wild-type levels of intracellular multiplication and the capacity to use erythritol as a sole carbon source. In vivo, the eryC mutant colonized the spleens of infected BALB/c mice to a significantly lower extent than the wild type and the complemented strain. Interestingly, eryC mutants that were in addition spontaneously erythritol tolerant nevertheless exhibited wild-type-like intramacrophagic and intramurine replication. We concluded from our results that erythritol was not an essential carbon source for the pathogen in the macrophage host cell but that the inactivation of the eryC gene significantly reduced the intramacrophagic and intramurine fitness of B. suis.  相似文献   
998.
Background: Fabry disease is an X linked lysosomal storage disease caused by deficiency of the lysosomal enzyme α-galactosidase A. This leads to accumulation of globotriaosylceramide in nearly all tissues, including the blood vessels, kidney, myocardium, and nervous system. Symptoms often begin in childhood and include acroparaesthesia, with burning or tingling pain that spreads from the extremities to more proximal sites.

Aims: This study set out to evaluate pain and its influence on quality of life in patients with Fabry disease receiving enzyme replacement therapy (ERT) with agalsidase alfa.

Methods: Data were obtained from the Fabry Outcome Survey. Pain was measured using the Brief Pain Inventory (BPI), and health-related quality of life (HRQoL) was documented with the European Quality of Life Questionnaire (EQ-5D).

Results: The mean (SD) score for "pain at its worst" on the BPI prior to ERT was 5.1 (2.7). One year after commencement of ERT, this had improved by 0.5, and improved by a further 0.6 after 2 years (p<0.05). Similar statistically significant improvements were seen for "pain on average" and "pain now" after 2 years of ERT. The mean HRQoL utility score prior to ERT was 0.66 (0.32). After 12 months of treatment with agalsidase alfa, this had improved to 0.74 (0.26; p<0.05); this improvement was maintained after 2 years.

Conclusions: ERT with agalsidase alfa significantly reduces pain and improves quality of life in patients with Fabry disease.

  相似文献   
999.
An allele-specific amplification method based on two genetic polymorphisms to differentiate Mycobacterium tuberculosis from Mycobacterium bovis was tested. Based on the differences found at position 169 in the pncA genes from M. tuberculosis and M. bovis, a PCR system which was able to differentiate most of the 237 M. tuberculosis complex isolates tested in one of the two species was developed. All 121 M. tuberculosis strains showed the expected base (cytosine) at position 169. Most of the M. bovis isolates had a guanine at the cited position. Nevertheless, 18 of the 116 M. bovis isolates, all of them goat isolates, showed the pncA polymorphism specific to M. tuberculosis. These results suggest that goat M. bovis may be the nicotinamidase-missing link at the origin of the M. tuberculosis species. Based on the polymorphism found at position 285 in the oxyR gene, the same system was used to differentiate M. tuberculosis from M. bovis. In this case, DNAs from all 121 M. tuberculosis isolates had the expected base (guanine) at this position. In addition, all 116 M. bovis isolates, including those from goats, showed the identical polymorphism (adenine). The oxyR allele-specific amplification method can differentiate M. bovis from M. tuberculosis, is rapid (results can be obtained in less than 3 h), and is easy to perform.  相似文献   
1000.
The human single-stranded DNA-binding replication A protein (RPA) is involved in various DNA-processing events. By comparing the affinity of hRPA for artificial DNA hairpin structures with 3′- or 5′-protruding single-stranded arms, we found that hRPA binds ssDNA with a defined polarity; a strong ssDNA interaction domain of hRPA is positioned at the 5′ side of its binding region, a weak ssDNA-binding domain resides at the 3′ side. Polarity appears crucial for positioning of the excision repair nucleases XPG and ERCC1–XPF on the DNA. With the 3′-oriented side of hRPA facing a duplex ssDNA junction, hRPA interacts with and stimulates ERCC1–XPF, whereas the 5′-oriented side of hRPA at a DNA junction allows stable binding of XPG to hRPA. Our data pinpoint hRPA to the undamaged strand during nucleotide excision repair. Polarity of hRPA on ssDNA is likely to contribute to the directionality of other hRPA-dependent processes as well.  相似文献   
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