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1.
This case control study aims to investigate the role of MMP-2 ?1306C > T polymorphism as a potential risk factor and possible prognostic marker for breast cancer in a South European population. 113 consecutive incident cases of histologically confirmed ductal breast cancer and 124 healthy controls were recruited. MMP-2 ?1306C > T polymorphism was genotyped; multivariate logistic regression as well as Cox regression analysis were performed. MMP-2 ?1306C > T status was not associated with breast cancer risk either at the total sample or at the subanalyses on premenopausal and postmenopausal women. At the survival analysis, a trend towards a favorable association between MMP-2 ?1306C > T allele and disease-free survival as well as overall survival was observed. Regarding subanalyses on ER-negative and ER-positive cases, the favorable association implicating MMP-2 ?1306C > T allele was particularly evident among ER-positive cases; no significant associations emerged among ER-negative cases. MMP-2 ?1306C > T polymorphism does not seem to be a risk factor for breast cancer in South European population; however, a trend towards a favorable association with survival has been observed.  相似文献   
2.
Oxytocin is a nine amino acid peptide involved in a wide spectrum of physiological functions; predominantly those concerning reproduction and differentiation are of interest. Oxytocin receptors are expressed at early developmental stages of mammals, suggesting that oxytocin might be involved in the determination of the germ stem cell line, at the very early stages of mammalian development. In this respect, the proximate aim of the present study was to confirm and further analyze the existence of oxytocin receptors at a very early level of cell commitment, that is, the determination of germ cells derived from embryoid bodies. To achieve our purpose we have cultured mouse embryonic stem cells under conditions inducing formation of embryoid bodies. In this work, ES cells were allowed to aggregate in a novel medium, “Stefanidis medium” from day 0 to day 14 until formed EBs. RNA was isolated from EBs and using RT-PCR we showed that EBs expressed Oct-4, OTR, OT, and DAZL. To demonstrate simultaneous expression immunocytochemistry was preformed, in which EBs showed strong immunoreactivity for both, OTR and DAZL molecular markers. We found that 35% of the cells displayed OTR, using flow cytometry. In addition, this novel medium showed to increase OTR mRNA. We propose, that at least in murine induced embryoid bodies there is simultaneous expression of oxytocin receptors and germ cell markers (DAZL) in many cells (expressing Oct-4). We thus conclude that, the oxytocin might indeed be a molecule playing a leading role in germ cell determination.  相似文献   
3.
BACKGROUND: Genetic skeletal disorders of the fetus and infant are a large group of genetic disorders, comprising the groups formerly assigned as skeletal dysplasias (osteochondrodysplasias), dysostoses, and malformation syndromes with a skeletal component. Genetic skeletal disorders may be prenatally detected by ultrasonography or result in intrauterine or early postnatal death, constituting one difficult diagnostic field met by the pathologist who performs the perinatal autopsy. METHODS: In this retrospective study, we have gathered radiologic, physical, histopathologic, and molecular data regarding 41 cases of genetic skeletal disorders diagnosed among 1980 fetal and perinatal autopsies over a 10‐year period. RESULTS: Our series of cases were classified according to the 2006 Nosology and Classification of Genetic Skeletal Disorders. The overall frequency of genetic skeletal disorders was 1:48 autopsies. The FGFR3 group and osteogenesis imperfecta type 2 were the more frequently encountered disorders. The mean gestational age at autopsy was 21.9 weeks (range, 12–37 weeks). A final diagnosis was obtained in 95% of cases. Genetic skeletal disorders were detected by prenatal ultrasound in 90% of cases, with a correct typing of the disorder achieved in only 34%. Molecular analysis was confirmative in 5 cases. CONCLUSIONS: The central role of the perinatal pathologist in collaboration with specialized services is essential for the correct interpretation of the radiologic, physical, and histopathologic findings, to accurately classify specific types of genetic skeletal disorders and enable genetic counseling. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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Invariant NKT (iNKT) cells are a subset of highly conserved immunoregulatory T cells that modify a variety of immune responses, including alloreactivity. Central to their function is the interaction of the invariant TCR with glycosphingolipid (GSL) ligands presented by the nonpolymorphic MHC class I molecule CD1d and their ability to secrete rapidly large amounts of immunomodulatory cytokines when activated. Whether iNKT cells, like NK and conventional T cells, can directly display alloreactivity is not known. We show in this study that human iNKT cells and APC can establish a direct cross-talk leading to preferential maturation of allogeneic APC and a considerably higher reactivity of iNKT cells cultured with allogeneic rather that autologous APC. Although the allogeneic activation of iNKT cells is invariant TCR-CD1d interaction-dependent, GSL profiling suggests it does not involve the recognition of disparate CD1d/GSL complexes. Instead, we show that contrary to previous reports, iNKT cells, like NK and T cells, express killer Ig receptors at a frequency similar to that of conventional T cells and that iNKT cell allogeneic activation requires up-regulation and function of activating killer Ig receptors. Thus, iNKT cells can display alloreactivity, for which they use mechanisms characteristic of both NK and conventional T cells.  相似文献   
7.

Background

Hyaluronan (HA) a glycosaminoglycan, is capable of transmitting extracellular matrix derived signals to regulate cellular functions. In this study, we investigated whether the changes in HT1080 and B6FS fibrosarcoma cell lines HA metabolism induced by basic fibroblast growth factor (bFGF) are correlated to their migration.

Methods

Real-time PCR, in vitro wound healing assay, siRNA transfection, enzyme digestions, western blotting and immunofluorescence were utilized.

Results

bFGF inhibited the degradation of HA by decreasing hyaluronidase-2 expression in HT1080 cells (p = 0.0028), increased HA-synthase-1 and -2 expression as we previously found and enhanced high molecular weight HA deposition in the pericellular matrix. Increased endogenous HA production (p = 0.0022) and treatment with exogenous high molecular weight HA (p = 0.0268) correlated with a significant decrease of HT1080 cell migration capacity. Transfection with siHAS2 and siHAS1 showed that mainly HAS1 synthesized high molecular weight HA regulates HT1080 cell motility. Induced degradation of the HA content by hyaluronidase treatment and addition of low molecular weight HA, resulted in a significant stimulation of HT1080 cells' motility (p < 0.01). In contrast, no effects on B6FS fibrosarcoma cell motility were observed.

Conclusions

bFGF regulates, in a cell-specific manner the migration capability of fibrosarcoma cells by modulating their HA metabolism.HA metabolism is suggested to be a potential therapeutic target in fibrosarcoma.  相似文献   
8.
Klinefelter syndrome is a sex chromosomal abnormality (47, XXY karyotype), occurring approximately in 1 in 1000 male live births. In the present study proteomic analysis was performed in twelve 2nd trimester amniotic fluid samples, eight coming from pregnancies with normal males and four with Klinefelter syndrome foetuses, as shown by routine prenatal cytogenetic analysis. Samples were analysed by 2-DE, coupled with MALDI-TOF-MS analysis. Three proteins (Ceruloplasmin, Alpha-1-antitrypsin and Zinc-alpha-2-glycoprotein) were found to be up-regulated in samples obtained from pregnancies with Klinefelter syndrome foetuses, whereas four proteins (Apolipoprotein A-I, Plasma retinol-binding protein, Gelsolin, and Vitamin D-binding protein) were down regulated when compared to proteins detected in samples from normal foetuses. The differential expression of Ceruloplasmin, Apolipoprotein A-I and Plasma retinol-binding protein was further confirmed by immunoblotting. Since these proteins are likely to cross the placenta barrier and be detected in maternal plasma they could be used as biomarkers for the non-invasive prenatal diagnosis of Klinefelter syndrome.  相似文献   
9.
Amino acid transport is an attractive target for oncologic imaging. Despite a high demand of cancer cells for cationic amino acids, their potential as PET probes remains unexplored. Arginine, in particular, is involved in a number of biosynthetic pathways that significantly influence carcinogenesis and tumor biology. Cationic amino acids are transported by several cationic transport systems including, ATB0,+ (SLC6A14), which is upregulated in certain human cancers including cervical, colorectal and estrogen receptor-positive breast cancer. In this work, we report the synthesis and preliminary biological evaluation of a new cationic analog of the clinically used PET tumor imaging agent O-(2-[18F]fluroethyl)-l-tyrosine ([18F]FET), namely O-2((2-[18F]fluoroethyl)methylamino)ethyltyrosine ([18F]FEMAET). Reference compound and precursor were prepared by multi-step approaches. Radiosynthesis was achieved by no-carrier-added nucleophilic [18F]fluorination in 16–20 % decay-corrected yields with radiochemical purity >99 %. The new tracer showed good stability in vitro and in vivo. Cell uptake assays demonstrated that FEMAET and [18F]FEMAET accumulate in prostate cancer (PC-3) and small cell lung cancer cells (NCI-H69), with an energy-dependent mechanism. Small animal PET imaging with NCI-H69 xenograft-bearing mice revealed good tumor visualization comparable to [18F]FET and low brain uptake, indicating negligible transport across the blood–brain barrier. In conclusion, the non-natural cationic amino acid PET probe [18F]FEMAET accumulates in cancer cells in vitro and in vivo with possible involvement of ATB0,+.  相似文献   
10.
We present a compelling case of simultaneous, bilateral tibial stress fractures occurring in a unique epiphyseal and posterior location, with unclear aetiology. An overweight, Caucasian male in his late 20s developed synchronous bilateral medial knee pain following an intense 10-day training regimen. His radiographies were normal, but MRI revealed almost identical bilateral stress fracture lines in the posteromedial tibial epiphyses. Bone mineral densitometry and a full metabolic and hormonal panel were performed to further investigate potential underlying metabolic bone disease. He was found to have normal bone mineral densitometry and low Vitamin D serum values. Symptomatology greatly improved with activity modification. There were no further complaints and complications at 12 months’ follow-up. Diagnosis can be challenging and the treating physician should be acquainted with the basic science of stress fractures and main discriminating clinical, biochemical and radiological characteristics from insufficiency fractures, to avoid pitfalls in treatment decision.  相似文献   
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