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21.
Little information is available regarding distribution of HPV types in different histological subtypes of adenocarcinoma (AC). Thus, in this study we examined the frequency of high-risk (hr) HPV types in AC, adenocarcinoma in situ (AIS) and adenosquamous carcinoma (ADSQ). A total of 102 cases of primary cervical adenocarcinoma (26 AIS and 76 invasive AC) obtained from pathology files from 1995-2006 were histologically subtyped. Our results demonstrated that endocervical type occupied the major subtype of AC (22/66) followed by ADSQ (17/66) where as in the group of AIS endocervical type (12/23) was followed by intestinal type of AIS (7/23). Successful DNA extraction was obtained in 89 samples; 81 out of 89 (91.0%) tested positive for HPV DNA. The prevalence of HPV DNA in AIS, AC and ADSQ was 91.3% (21/23), 90.9% (60/66) and 94.1% (16/17), respectively. We found HPV 18 type to be the most predominant type in AIS (11/21) and AC (17/60) followed by HPVof undeternmined type in AIS (3/21) and HPV 16 in AC (9/60) as the sole viral type. HPV 18 was most frequently detected type in all histological subtypes of AIS and AC. We have detected HPV DNA in all 5 samples of clear cell carcinoma (CCC), although other studies have reported a highly variable prevalence of HPVDNA in CCC. The most prevalent HPV type in ADSQ was HPV-16 followed by HPV 33 as single type. The observed overall predominance of HPV 18 in AIS (chi(2) = 6.109, p< or = 0.025) and AC (chi(2) = 8.927, p< or =0.01) as well as of HPV 16 in ADSQ (chi(2) = 10.164, p < or = 0.01) was statistically significant. Our data revealed statistically significant predominance of single hrHPV infections in AIS (16/21; chi(2) = 11.523, p < 0.001) and AC (37/60; X2 = 6.533, p < 0.025) whereas multiple hrHPV infections were more abundant in AC comparing to AIS (23/81and 5/81, respectively; chi(2) = 13.989, p< or =0.001).  相似文献   
22.
The aim of this study was to examine health-related quality of life among Croatian HIV infected individuals, and to assess the impact of socio-demographic and disease-related variables on health-related quality of life. This was a crosssectional study of 111 HIV-infected adults who received care at the University Hospital for Infectious Diseases in Zagreb, Croatia. The World Health Organization Quality of Life Questionnaire for HIV brief version (WHOQOL-HIV BREF) was used to assess each patient's quality of life. Ratings of quality of life differed across age, marital status, level of education, health status and "currently ill" status. Subjects who perceived themselves as not ill and their health status as better reported better quality of life for all quality of life domains (p < 0.01). Subjects who were in relationships gave higher ratings for the social relationships domain (p < 0.01). Subjects with higher level of education gave significantly higher ratings within the independence (p < 0.05) and environment (p < 0.01) domains. Younger subjects perceived their psychological state as better (p < 0.05). The findings demonstrate a moderate degree of overall quality of life (X = 112.2; SD = 18.92) with main concerns related to social relationships. These results highlight the need for better access to psychosocial support and medical and legal services for people living with HIV/AIDS in Croatia.  相似文献   
23.
Cell detachment procedures can cause severe damage to cells. Many studies require cells to be detached before measurements; therefore, research on cells that have been grown attached to the bottom of the culture dish and later detached represents a special problem with respect to the experimental results when the properties of cell membranes undergo small changes such as in spectroscopic studies of membrane permeability. We characterized the influence of three different detachment procedures: cell scraping by rubber policeman, trypsinization and a citrate buffer treatment on V‐79 cells in the plateau phase of growth (arrested in G1). We have measured cell viability by a dye‐exclusion test; nitroxide reduction kinetics and membrane fluidity by EPR (electron paramagnetic resonance) method using the lipophilic spin‐probe MeFASL(10,3) (5‐doxylpalmitoyl‐methylester), which partitions mainly in cell membranes and the hydrophilic spin‐probe TEMPONE (4‐oxo‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl). The resulting cell damage due to the detachment process was observed with SEM (scanning electron microscopy). We found out that cell viability was 91% for trypsin treatment, 85% for citrate treatment and 70% for cell scraping. Though the plasma membrane was mechanically damaged by scraping, the membrane domain structure was not significantly altered compared with other detachment methods. On the other hand, the spin‐probe reduction rate, which depends both on the transport across plasma membrane as well as on metabolic properties of cells, was the highest for trypsin method, suggesting that metabolic rate was the least influenced. Only the reduction rate of trypsin‐treated cells stayed unchanged after 4 h of stirring in suspension. These results suggest that, compared with scraping cells or using citrate buffer, the most suitable detachment method for V‐79 cells is detachment by trypsin and keeping cells in the stirred cell suspension until measurement. This method provides the highest cell viability, less visible damage on SEM micrographs and leaves the metabolic rate of cells unchanged.  相似文献   
24.
C3H/HeCr mice are more susceptible to infection compared with other strains. Lactoferrin (LF), a protein involved in innate defense, was shown to protect mice against lethal endotoxemia. In this investigation we attempt to explain the cause of increased susceptibility of C3H/HeCr mice to LPS and lack of protective LF action in these mice. We found that C3H/HeCr mice produced up to 5-fold more serum TNFalpha and 66% higher IFNgamma levels in response to i.v. LPS injection than the control, CBA strain. 24 h pretreatment of C3H/HeCr mice with LF did not cause inhibition of the LPS-induced TNFalpha serum levels, whereas in CBA mice LF significantly decreased TNFalpha level. IL-6 serum levels, in turn, were lowered in C3H/HeCr mice but elevated in CBA mice. That differential regulation of cytokine production by LF in C3H/HeCr mice paralleled a decreased survival after lethal LPS injection - 10% vs. 60% in control, PBS treated mice. In addition, determination of colony forming units (CFU) in livers and spleens after administration of 10(8) Escherichia coli revealed that pretreatment of CBA mice with LF caused a marked reduction of CFU in these organs, whereas in C3H/HeCr mice the changes were insignificant. These results indicate that the altered TNFalpha/IL-6 ratio in C3H/HeCr mice, as compared to control CBA mice, as well as the increased IFNgamma level, may be responsible for the increased susceptibility to endotoxemia in that substrain. We also suggest that an association exists between the LF protective effect against endotoxic sequelae and the insult-induced systemic immune response.  相似文献   
25.
Human cytomegalovirus (HCMV) forms two gH/gL glycoprotein complexes, gH/gL/gO and gH/gL/pUL(128,130,131A), which determine the tropism, the entry pathways and the mode of spread of the virus. For murine cytomegalovirus (MCMV), which serves as a model for HCMV, a gH/gL/gO complex functionally homologous to the HCMV gH/gL/gO complex has been described. Knock-out of MCMV gO does impair, but not abolish, virus spread indicating that also MCMV might form an alternative gH/gL complex. Here, we show that the MCMV CC chemokine MCK-2 forms a complex with the glycoprotein gH, a complex which is incorporated into the virion. We could additionally show that mutants lacking both, gO and MCK-2 are not able to produce infectious virus. Trans-complementation of these double mutants with either gO or MCK-2 showed that both proteins can promote infection of host cells, although through different entry pathways. MCK-2 has been extensively studied in vivo by others. It has been shown to be involved in attracting cells for virus dissemination and in regulating antiviral host responses. We now show that MCK-2, by forming a complex with gH, strongly promotes infection of macrophages in vitro and in vivo. Thus, MCK-2 may play a dual role in MCMV infection, as a chemokine regulating the host response and attracting specific target cells and as part of a glycoprotein complex promoting entry into cells crucial for virus dissemination.  相似文献   
26.
Endoglin is a transforming growth factor-β (TGF- β) co-receptor that participates in the activation of a signaling pathway that mediates endothelial cell proliferation and migration in angiogenic tumor vasculature. Therefore, silencing of endoglin expression is an attractive approach for antiangiogenic therapy of tumors. The aim of our study was to evaluate the therapeutic potential of small interfering RNA (siRNA) molecules against endoglin in vitro and in vivo. Therapeutic potential in vitro was assessed in human and murine endothelial cells (HMEC-1, 2H11) by determining endoglin expression level, cell proliferation and tube formation. In vivo, the therapeutic potential of siRNA molecules was evaluated in TS/A mammary adenocarcinoma growing in BALB/c mice. Results of our study showed that siRNA molecules against endoglin have a good antiangiogenic therapeutic potential in vitro, as expression of endoglin mRNA and protein levels in mouse and human microvascular endothelial cells after lipofection were efficiently reduced, which resulted in the inhibition of endothelial cell proliferation and tube formation. In vivo, silencing of endoglin with triple electrotransfer of siRNA molecules into TS/A mammary adenocarcinoma also significantly reduced the mRNA levels, number of tumor blood vessels and the growth of tumors. The obtained results demonstrate that silencing of endoglin is a promising antiangiogenic therapy of tumors that could not be used as single treatment, but as an adjunct to the established cytotoxic treatment approaches.  相似文献   
27.
NY-ESO-1 and LAGE-1 are cancer testis antigens with an ideal profile for tumor immunotherapy, combining up-regulation in many cancer types with highly restricted expression in normal tissues and sharing a common HLA-A*0201 epitope, 157–165. Here, we present data to describe the specificity and anti-tumor activity of a bifunctional ImmTAC, comprising a soluble, high-affinity T-cell receptor (TCR) specific for NY-ESO-1157–165 fused to an anti-CD3 scFv. This reagent, ImmTAC-NYE, is shown to kill HLA-A2, antigen-positive tumor cell lines, and freshly isolated HLA-A2- and LAGE-1-positive NSCLC cells. Employing time-domain optical imaging, we demonstrate in vivo targeting of fluorescently labelled high-affinity NYESO-specific TCRs to HLA-A2-, NY-ESO-1157–165-positive tumors in xenografted mice. In vivo ImmTAC-NYE efficacy was tested in a tumor model in which human lymphocytes were stably co-engrafted into NSG mice harboring tumor xenografts; efficacy was observed in both tumor prevention and established tumor models using a GFP fluorescence readout. Quantitative RT-PCR was used to analyze the expression of both NY-ESO-1 and LAGE-1 antigens in 15 normal tissues, 5 cancer cell lines, 10 NSCLC, and 10 ovarian cancer samples. Overall, LAGE-1 RNA was expressed at a greater frequency and at higher levels than NY-ESO-1 in the tumor samples. These data support the clinical utility of ImmTAC-NYE as an immunotherapeutic agent for a variety of cancers.  相似文献   
28.

Background

Targeted Next Generation Sequencing (NGS) offers a way to implement testing of multiple genetic aberrations in diagnostic pathology practice, which is necessary for personalized cancer treatment. However, no standards regarding input material have been defined. This study therefore aimed to determine the effect of the type of input material (e.g. formalin fixed paraffin embedded (FFPE) versus fresh frozen (FF) tissue) on NGS derived results. Moreover, this study aimed to explore a standardized analysis pipeline to support consistent clinical decision-making.

Method

We used the Ion Torrent PGM sequencing platform in combination with the Ion AmpliSeq Cancer Hotspot Panel v2 to sequence frequently mutated regions in 50 cancer related genes, and validated the NGS detected variants in 250 FFPE samples using standard diagnostic assays. Next, 386 tumour samples were sequenced to explore the effect of input material on variant detection variables. For variant calling, Ion Torrent analysis software was supplemented with additional variant annotation and filtering.

Results

Both FFPE and FF tissue could be sequenced reliably with a sensitivity of 99.1%. Validation showed a 98.5% concordance between NGS and conventional sequencing techniques, where NGS provided both the advantage of low input DNA concentration and the detection of low-frequency variants. The reliability of mutation analysis could be further improved with manual inspection of sequence data.

Conclusion

Targeted NGS can be reliably implemented in cancer diagnostics using both FFPE and FF tissue when using appropriate analysis settings, even with low input DNA.  相似文献   
29.
Human monoclonal antibodies are promising agents for the development of more selective anticancer therapeutics. However, the tumor-targeting efficiency of most anticancer antibodies is severely limited by their poor penetration into the tumor mass. Recent studies have shown that a peptide derived from the HIV TAT protein could improve the distribution of cytoplasmic reporter proteins when administered systemically as fusion proteins or cross-linked chimeras. In this article, we tested by quantitative biodistribtution analysis whether conjugation to TAT peptides could improve the tumor targeting properties of scFv(L19)-Cys: an engineered human antibody fragment specific for the ED-B domain of fibronectin, a marker located in the modified extracellular matrix surrounding tumor neovasculature. Our results show that TAT peptides, consisting either of L-amino acids or D-amino acids, can efficiently transduce target cells when conjugated to fluorophores and/or antibody fragments, suggesting a receptor-independent cell entry mechanism. However, conjugation of scFv(L19)-Cys to TAT peptides resulted in a severely reduced tumor targeting performance compared to the unconjugated antibody, as measured in murine F9 teratocarcinoma-bearing mice, after intravenous injection of the radiolabeled antibody preparations. Our results outline the usefulness of TAT peptides for the efficient in vitro transduction of cells with globular proteins. In particular, the use of TAT peptides composed of D-amino acids may significantly reduce proteolytic degradation. At the same time, the poor biodistribution properties of antibody-TAT conjugates cast doubts over the applicability of this methodology for the delivery of biopharmaceuticals in vivo.  相似文献   
30.
Thrombin aptamer binding strength and stability is dependent on sterical parameters when used for atomic force microscopy sensing applications. Sterical improvements on the linker chemistry were developed for high-affinity binding. For this we applied single molecule force spectroscopy using two enhanced biotinylated thrombin aptamers, BFF and BFA immobilized on the atomic force microscopy tip via streptavidin. BFF is a dimer composed of two single-stranded aptamers (aptabody) connected to each other by a complementary sequence close to the biotinylated end. In contrast, BFA consists of a single DNA strand and a complementary strand in the supporting biotinylated part. By varying the pulling velocity in force-distance cycles the formed thrombin-aptamer complexes were ruptured at different force loadings allowing determination of the energy landscape. As a result, BFA aptamer showed a higher binding force at the investigated loading rates and a significantly lower dissociation rate constant, koff, compared to BFF. Moreover, the potential of the aptabody BFF to form a bivalent complex could clearly be demonstrated.  相似文献   
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