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71.
We report a case of basaloid squamous carcinoma with a spindle cell component of the hypopharynx, in a 61-years-old-man. An excisional biopsy of a pedonculated and polypoid tumour was performed by endoscopy. The histologic examination revealed a biphasic tumour with both a basaloid carcinomatous and a spindle cell component. Focally, osseous metaplasia was seen. The spindle cell component demonstrated immunoreactivity with the p63 epithelial marker. The patient was treated with chemotherapy followed by radiotherapy. The patient has been free of disease for one year. It's the ninth case reported in the literature of a biphasic carcinoma with both a basaloid squamous and a spindle cell component and the first case with osseous metaplasia.  相似文献   
72.
The aim of the present study was to achieve the immobilization of dermatan sulfate (DS) on polyethylene terephthalate (PET) surfaces and to evaluate its biocompatibility. DS obtained from the skin of Scyliorhinus canicula shark was immobilized via carbodiimide on knitted PET fabrics, modified with carboxyl groups. PET-DS characterization was performed by SEM, ATR-FTIR and contact angle measurements. Biocompatibility was evaluated by investigating plasma protein adsorption and endothelial cell proliferation, as well as by subcutaneous implantations in rats. The results indicated that DS immobilization on PET was achieved at ~8 μg/cm2. ATR-FTIR evidenced the presence of sulfate groups on the PET surface. In turn, contact angle measurements indicated an increase in the surface wettability. DS immobilization increased albumin adsorption on the PET surface, whereas it decreased that of fibrinogen. In vitro cell culture revealed that endothelial cell proliferation was also enhanced on PET-DS. Histological results after 15 days of subcutaneous implantation showed a better integration of PET-DS samples in comparison to those of nonmodified PET. In summary, DS was successfully grafted onto the surface of PET, providing it new physicochemical characteristics and biological properties for PET, thus enhancing its biointegration.  相似文献   
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74.
The poor specificity of diagnostic strategy for prostate cancer (digital rectal examination and seric PSA) induces both a great number of useless prostate biopsies and diagnosis of non evolutive cancers. A urinary test (Progensa PCA3(?), Gen-Probe) measuring the expression of PCA3, a prostate cancer-specific gene, has recently be proposed to indicate re-biopsy. The aim of this prospective study was to evaluate diagnostic value of urinary PCA3 test for prostate cancer. In the urines of 245 patients submitted to prostate biopsy, expression of the PCA3 gene was measured and reported to that of PSA to calculate PCA3 score using a method amplifying and detecting RNA. Patients with informative samples (98%) were classified depending of the presence (n?=?126) or absence (n?=?114) of cancer tissue on biopsies. The median PCA3 score was significantly higher in the group with positive biopsies (p?相似文献   
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76.
NK cells are key players in the fight against persistent viruses. Human cytomegalovirus (HCMV) infection is associated with the presence of a population of CD16+ CD56dim NKG2C+ NK cells in both acutely and latently infected individuals. Here, we studied the nature of these terminally differentiated NK cells in different human populations infected with HCMV: healthy donors stratified by age, thymectomized individuals, pregnant women suffering from primary CMV infection, and lung transplant patients. Both CD16+ CD56dim NK‐ and CD8 T‐cell phenotypes as well as functional capacities were determined and stratified according to age and/or CMV event. Similarly to T‐cell responsiveness, we observe an accumulation over time of NKG2C+ NK cells, which preferentially expressed CD57. This accumulation is particularly prominent in elderly and amplified further by CMV infection. Latent HCMV infection (without replication) is sufficient for NKG2C+ CD57+ NK cells to persist in healthy individuals but is not necessarily required in old age. Collectively, the present work supports the emerging concept that CMV shapes both innate and adaptive immunity in humans.  相似文献   
77.
Hepatitis A virus (HAV) is a worldwide disease; in most cases, it causes an acute self-limited illness that does not lead to a chronic state. The course of HAV viremia in a homosexual male with human immunodeficiency virus type 1 (HIV-1) and the correlation between HIV and HAV viral load, alanine aminotranferase (ALT) level, and CD4(+) lymphocyte count were investigated during the course of the infection. HAV RNA was detected quantitatively up to 256 days after clinical onset. To our knowledge, this specific case is the first report of a prolonged infection with hepatitis A in a male with HIV-1. The ALT levels decreased gradually; however, 286 days after clinical onset of hepatitis, ALT levels were three times higher than normal values. HIV viral load was not affected by the infection with HAV and CD4(+) cell count was stable during the course of the co-infection. The duration and the high-titer viremia of hepatitis A virus in an immunodeficient patient constitute a serious risk of the spread of hepatitis A within this population. As inactivated HAV vaccine is safe in HIV-positive subjects, it would be wise to establish a strategy of preventive vaccination in this high-risk group.  相似文献   
78.
Proximal 19p13.12 microdeletion has been rarely reported. Only five postnatal cases with intellectual disability, facial dysmorphism, branchial arch defects and overlapping deletions involving proximal 19p13.12 have been documented. Two critical intervals were previously defined: a 700 kb for branchial arch defects and a 350 kb for hypertrichosis-synophrys-protruding front teeth. We describe the first prenatal case, a fetal death in utero at 39 weeks of gestation. Agilent 180K array-CGH analysis identified a heterozygous interstitial 745 kb deletion at 19p13.12 chromosome region, encompassing both previously reported critical intervals, including at least 6 functionally relevant genes: NOTCH3, SYDE1, AKAP8, AKAP8L, WIZ and BRD4. Quantitative PCR showed that the deletion occurred de novo with a median size of 753 kb. NOTCH3 and SYDE1 were candidate genes for placental pathology whilst AKAP8, AKAP8L, WIZ and BRD4 were highly expressed in the branchial arches. Molecular characterization and sequencing of candidate genes for placental pathology and branchial arch defects were carried out in order to correlate the genotype-phenotype relationship and unravel the underlying mechanism of proximal 19p13.12 microdeletion syndrome. This case also contributes to define the novel critical interval and expand the clinical phenotype spectrum of proximal 19p13.12 microdeletion syndrome.  相似文献   
79.
Identifying signaling pathways that regulate hematopoietic stem and progenitor cell (HSPC) formation in the embryo will guide efforts to produce and expand HSPCs ex vivo. Here we show that sterile tonic inflammatory signaling regulates embryonic HSPC formation. Expression profiling of progenitors with lymphoid potential and hematopoietic stem cells (HSCs) from aorta/gonad/mesonephros (AGM) regions of midgestation mouse embryos revealed a robust innate immune/inflammatory signature. Mouse embryos lacking interferon γ (IFN-γ) or IFN-α signaling and zebrafish morphants lacking IFN-γ and IFN-ϕ activity had significantly fewer AGM HSPCs. Conversely, knockdown of IFN regulatory factor 2 (IRF2), a negative regulator of IFN signaling, increased expression of IFN target genes and HSPC production in zebrafish. Chromatin immunoprecipitation (ChIP) combined with sequencing (ChIP-seq) and expression analyses demonstrated that IRF2-occupied genes identified in human fetal liver CD34+ HSPCs are actively transcribed in human and mouse HSPCs. Furthermore, we demonstrate that the primitive myeloid population contributes to the local inflammatory response to impact the scale of HSPC production in the AGM region. Thus, sterile inflammatory signaling is an evolutionarily conserved pathway regulating the production of HSPCs during embryonic development.  相似文献   
80.
Functional proteomics mapping of a human signaling pathway   总被引:5,自引:0,他引:5       下载免费PDF全文
Access to the human genome facilitates extensive functional proteomics studies. Here, we present an integrated approach combining large-scale protein interaction mapping, exploration of the interaction network, and cellular functional assays performed on newly identified proteins involved in a human signaling pathway. As a proof of principle, we studied the Smad signaling system, which is regulated by members of the transforming growth factor beta (TGFbeta) superfamily. We used two-hybrid screening to map Smad signaling protein-protein interactions and to establish a network of 755 interactions, involving 591 proteins, 179 of which were poorly or not annotated. The exploration of such complex interaction databases is improved by the use of PIMRider, a dedicated navigation tool accessible through the Web. The biological meaning of this network is illustrated by the presence of 18 known Smad-associated proteins. Functional assays performed in mammalian cells including siRNA knock-down experiments identified eight novel proteins involved in Smad signaling, thus validating this integrated functional proteomics approach.  相似文献   
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