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Growth arrest specific 1 (GAS1) is a pleiotropic protein that induces apoptosis and cell arrest in different tumors, but it is also involved in the development of the nervous system and other tissues and organs. This dual ability is likely caused by its capacity to interact both by inhibiting the intracellular signaling cascade induced by glial cell-line derived neurotrophic factor and by facilitating the activity of the sonic hedgehog pathway. The presence of GAS1 mRNA has been described in adult mouse brain, and here we corroborated this observation. We then proceeded to determine the distribution of the protein in the adult central nervous system (CNS). We detected, by western blot analysis, expression of GAS1 in olfactory bulb, caudate-putamen, cerebral cortex, hippocampus, mesencephalon, medulla oblongata, cerebellum, and cervical spinal cord. To more carefully map the expression of GAS1, we performed double-label immunohistochemistry and noticed expression of GAS1 in neurons in all brain areas examined. We also observed expression of GAS1 in astroglial cells, albeit the pattern of expression was more restricted than that seen in neurons. Briefly, in the present article, we report the widespread distribution and cellular localization of the GAS1 native protein in adult mammalian CNS.  相似文献   
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Recently, there are controversial opinions on the presence of Mycoplasmas/Ureaplasmas as colonizers or pathogens, and on the use of a targeted therapy. This study aimed to characterize Mycoplasmas/Ureaplasmas infections in reproductive age women, including the acquisition of sexually transmitted (ST) pathogens and poor birth outcomes. A total of 646 healthy Italian women fulfilled the inclusion criteria including 521 infertile women, 65 pregnant women, and 60 fertile women with identified risk factors and symptomatic for vaginitis/cervicitis. Multiplex and quantitative molecular techniques and direct automatic DNA sequencing were performed to assess the genome structure of Mycoplasma/Ureaplasma species and ST infected pathogens. Ureaplasma parvum serovar 3 represented the predominant colonizer of the urogenital tract of this series and the unique species significantly associated with ST pathogens coinfection (p < 0.01). U. parvum load >104 bacteria/ml, suggestive of active infection, has been measured only in asymptomatic high-risk human papillomavirus infected women (24.3%) and in 40% of women with idiopathic infertility. To note, 16% of the follicular fluid from these idiopathic women resulted infected with U. parvum. In conclusion, the present study focused the attention on U. parvum serovar 3 as emerging microorganism in sexually active women that may have the benefit of targeted therapy.  相似文献   
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Bovine lactoferrin catalyzes the hydrolysis of synthetic substrates (i.e., Z-aminoacyl-7-amido-4-methylcoumarin). Values of Km and kcat for the bovine lactoferrin catalyzed hydrolysis of Z-Phe-Arg-7-amido-4-methylcoumarin are 50 microM and 0.03 s(-1), respectively, the optimum pH value is 7.5 at 25 degrees C. The bovine lactoferrin substrate specificity is similar to that of trypsin, while the hydrolysis rate is several orders of magnitude lower than that of trypsin. The bovine lactoferrin catalytic activity is irreversibly inhibited by the serine-protease inhibitors PMSF and Pefabloc. Moreover, both iron-saturation of the protein and LPS addition strongly inhibit the bovine lactoferrin activity. Interestingly, bovine lactoferrin undergoes partial auto-proteolytic cleavage at positions Arg415-Lys416 and Lys440-Lys441. pKa shift calculations indicate that several Ser residues of bovine lactoferrin display the high nucleophilicity required to potentially catalyze substrate cleavage. However, a definitive identification of the active site awaits further studies.  相似文献   
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Objective

Polyomavirus simian virus 40 (SV40) sequences have been detected in various human specimens and SV40 antibodies have been found in human sera from both healthy individuals and cancer patients. This study analyzed serum samples from healthy pregnant women as well as cord blood samples to determine the prevalence of SV40 antibodies in pregnancy.

Methods

Serum samples were collected at the time of delivery from two groups of pregnant women as well as cord bloods from one group. The women were born between 1967 and 1993. Samples were assayed by two different serological methods, one group by neutralization of viral infectivity and the other by indirect ELISA employing specific SV40 mimotopes as antigens. Viral DNA assays by real-time polymerase chain reaction were carried out on blood samples.

Results

Neutralization and ELISA tests indicated that the pregnant women were SV40 antibody-positive with overall prevalences of 10.6% (13/123) and 12.7% (14/110), respectively. SV40 neutralizing antibodies were detected in a low number of cord blood samples. Antibody titers were generally low. No viral DNA was detected in either maternal or cord bloods.

Conclusions

SV40-specific serum antibodies were detected in pregnant women at the time of delivery and in cord bloods. There was no evidence of transplacental transmission of SV40. These data indicate that SV40 is circulating at a low prevalence in the northern Italian population long after the use of contaminated vaccines.  相似文献   
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The α-ASTREE e-Tongue instrument uses seven sensors to characterize taste signals associated with a liquid sample. The instrument was used to study eight test preparations (comprised of a blank, four preparations corresponding to four known tastes and Sodium Topiramate in three concentrations known to have a bitter taste) and eight washes. Serially balanced residual effects designs were used to order the samples to estimate residual and main effects. The design provided for eight repeated measurements per test preparation. The experimental results suggested the following: (1) The seven sensors can be separated into three groups according to the ability to discriminate test preparations, and three of the sensors contributed little or no information. Further investigation suggested the lack of differentiability might be due to the age of the sensors. (2) The sensors discriminated known tastes from blank. The residual effect due to test preparations might appear after repeated usage. (3) Exploratory principal component analysis of the data indicated that nearly 90% of the total variability across the seven sensors could be explained by a single principal component. (4) The four standard taste preparations did not correspond to orthogonal dimensions in the principal component axes. (5) The three Sodium Topiramate test preparations could neither be associated with the corresponding known bitter taste sample nor could the three doses be shown to follow a quantitative dose-response relationship on the e-Tongue measurement scale. The practical interpretation of the results of the statistical analysis indicates only poor discriminative ability of the e-Tongue to distinguish clearly between increasing concentrations of a known bitter compound such as Sodium Topiramate. No apparent linear relationship could be discerned over increasing concentrations that would allow the quantification of bitterness.KEY WORDS: cluster analysis, electronic tongue, principal component analysis, residual effects designs, serially balanced design  相似文献   
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Background

Tuberous sclerosis (TSC) related tumors are characterized by constitutively activated mTOR signaling due to mutations in TSC1 or TSC2.

Methods

We completed a phase 2 multicenter trial to evaluate the efficacy and tolerability of the mTOR inhibitor, sirolimus, for the treatment of kidney angiomyolipomas.

Results

36 adults with TSC or TSC/LAM were enrolled and started on daily sirolimus. The overall response rate was 44.4% (95% confidence intervals [CI] 28 to 61); 16/36 had a partial response. The remainder had stable disease (47.2%, 17/36), or were unevaluable (8.3%, 3/36). The mean decrease in kidney tumor size (sum of the longest diameters [sum LD]) was 29.9% (95% CI, 22 to 37; n = 28 at week 52). Drug related grade 1–2 toxicities that occurred with a frequency of >20% included: stomatitis, hypertriglyceridemia, hypercholesterolemia, bone marrow suppression (anemia, mild neutropenia, leucopenia), proteinuria, and joint pain. There were three drug related grade 3 events: lymphopenia, headache, weight gain. Kidney angiomyolipomas regrew when sirolimus was discontinued but responses tended to persist if treatment was continued after week 52. We observed regression of brain tumors (SEGAs) in 7/11 cases (26% mean decrease in diameter), regression of liver angiomyolipomas in 4/5 cases (32.1% mean decrease in longest diameter), subjective improvement in facial angiofibromas in 57%, and stable lung function in women with TSC/LAM (n = 15). A correlative biomarker study showed that serum VEGF-D levels are elevated at baseline, decrease with sirolimus treatment, and correlate with kidney angiomyolipoma size (Spearman correlation coefficient 0.54, p = 0.001, at baseline).

Conclusions

Sirolimus treatment for 52 weeks induced regression of kidney angiomyolipomas, SEGAs, and liver angiomyolipomas. Serum VEGF-D may be a useful biomarker for monitoring kidney angiomyolipoma size. Future studies are needed to determine benefits and risks of longer duration treatment in adults and children with TSC.

Trial Registration

Clinicaltrials.gov NCT00126672  相似文献   
10.
Invasive pulmonary aspergillosis is typically caused by a single Aspergillus species, most frequently Aspergillus fumigatus. Here we report that a lung transplant recipient developed invasive aspergillosis due to a mixed infection caused by Aspergillus flavus and A. fumigatus. The implications for this unusual finding are discussed.  相似文献   
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