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The perpendicular magnetocrystalline anisotropy, magnetoelastic properties as well as the Gilbert damping factor in Co2Fe0.4Mn0.6Si thin films were found to depend on a magnetic layer thickness, and they can be also tuned by the application of additional Ag buffer layer. The tetragonal distortion of a magnetic layer was found to increase with decreasing thickness, and after the application of an additional Ag buffer layer, the character of this distortion was changed from tensile to compressive in the plane of a film. A correlation between the tetragonal distortion and perpendicular magnetocrystalline anisotropy was found. However, the magnitude of the observed tetragonal distortion for most samples seems to be too small to explain alone the experimentally found large magnitude of the perpendicular magnetocrystalline anisotropy. For these samples, other mechanisms including both surface and volume effects must be taken into account. [ABSTRACT FROM AUTHOR]

The influence of the addition of Bi to the dilute ferromagnetic semiconductor (Ga,Mn)As on its electronic structure as well as on its magnetic and structural properties has been studied. Epitaxial (Ga,Mn)(Bi,As) layers of high structural perfection have been grown using low-temperature molecular-beam epitaxy. Post-growth annealing of the samples improves their structural and magnetic properties and increases the hole concentration in the layers. Hard X-ray angle-resolved photoemission spectroscopy reveals a strongly dispersing band in the Mn-doped layers, which crosses the Fermi energy and is caused by the high concentration of Mn-induced itinerant holes located in the valence band. An increased density of states near the Fermi level is attributed to additional localized Mn states. In addition to a decrease in the chemical potential with increasing Mn doping, we find significant changes in the valence band caused by the incorporation of a small atomic fraction of Bi atoms. The spin–orbit split-off band is shifted to higher binding energies, which is inconsistent with the impurity band model of the band structure in (Ga,Mn)As. Spectroscopic ellipsometry and modulation photoreflectance spectroscopy results confirm the valence band modifications in the investigated layers. [ABSTRACT FROM AUTHOR]

Incorporation of Bi into GaAs-(Ga,Al)As-Ga(As,Bi) core–shell nanowires grown by molecular beam epitaxy is studied with transmission electron microscopy. Nanowires are grown on GaAs(111)B substrates with Au-droplet assisted mode. Bi-doped shells are grown at low temperature (300 °C) with a close to stoichiometric Ga/As flux ratio. At low Bi fluxes, the Ga(As,Bi) shells are smooth, with Bi completely incorporated into the shells. Higher Bi fluxes (Bi/As flux ratio ~ 4%) led to partial segregation of Bi as droplets on the nanowires sidewalls, preferentially located at the nanowire segments with wurtzite structure. We demonstrate that such Bi droplets on the sidewalls act as catalysts for the growth of branches perpendicular to the GaAs trunks. Due to the tunability between zinc-blende and wurtzite polytypes by changing the nanowire growth conditions, this effect enables fabrication of branched nanowire architectures with branches generated from selected (wurtzite) nanowire segments. [ABSTRACT FROM AUTHOR]

Ultrasound-guided thrombin injection (UGTI) is often the first-line treatment for iatrogenic post-catheterization pseudoaneurysms (psA). There are also first reports of the use of biologically derived tissue glues (TG) instead of sole thrombin especially when UGTI was unsuccessful or in case of psA recurrence. Previously, we have established that a late to early velocity index (LEVI) < 0.2 could be a predictor of an increased risk of psA recurrence after standard UGTI. In this paper, we report our first experiences when the choice of the first-line treatment method was based on LEVI assessment. From May 2017 till January 2020 we included 36 patients with psA. Of them, 10 had LEVI < 0.2 and they underwent ultrasound-guided tissue glue injection (UGTGI) with biological TG and 26 had LEVI > 0.2 and they underwent UGTI. The injection set containing human thrombin and fibrinogen was used for UGTGI. Bovine thrombin was used for UGTI. The success rate was 100% and no psA recurrence was detected during a 2-week follow-up. It was significantly better when compared to the expected recurrence rates based on our previous 14 years of experience (0% vs. 13%, p = 0.01). All complications (10% in the UGTGI group and 15% in the UGTI group) were mild and transient and included clinical symptoms of paresthesia, numbness, tingling, or pain. Their rates were comparable to the rates we previously reported. No significant differences in other characteristics were observed. The approach to choose the first-line treatment method for iatrogenic psA based on LEVI is encouraging. It may increase the success rate and avoid unnecessary repetition of the procedure, without increasing complication rate while keeping costs of the procedure reasonable. [ABSTRACT FROM AUTHOR]

Co2Fe0.4Mn0.6Si (CFMS) and Co2FeGa0.5Ge0.5 (CFGG) Heusler alloys are among the most promising thin film materials for spintronic devices due to a high spin polarization, low magnetic damping and giant/tunneling magnetoresistance ratios. Despite numerous investigations of Heusler alloys magnetic properties performed up to now, magnetoelastic effects in these materials remain not fully understood; due to quite rare studies of correlations between magnetoelastic and other magnetic properties, such as magnetic dissipation or magnetic anisotropy. In this research we have investigated epitaxial CFMS and CFGG Heusler alloys thin films of thickness in the range of 15–50 nm. We have determined the magnetoelastic tensor components and magnetic damping parameters as a function of the magnetic layer thickness. Magnetic damping measurements revealed the existence of non-Gilbert dissipation related contributions, including two-magnon scattering and spin pumping phenomena. Magnetoelastic constant B11 values and the effective magnetic damping parameter αeff values were found to be in the range of − 6 to 30 × 106 erg/cm3 and between 1 and 12 × 10–3, respectively. The values of saturation magnetostriction λS for CFMS Heusler alloy thin films were also obtained using the strain modulated ferromagnetic resonance technique. The correlation between αeff and B11, depending on magnetic layer thickness was determined based on the performed investigations of the above mentioned magnetic properties. [ABSTRACT FROM AUTHOR]

Background: Left atrial appendage closure (LAAC) is an alternative treatment strategy for patients with atrial fibrillation who are at risk for thromboembolic events and considered not suitable for oral anticoagulation (OAC). LAAC is mainly performed under the guidance of transesophageal echocardiography (TEE) and fluoroscopy. The study presented here should analyze whether fusion imaging (FI) of transesophageal echocardiography and X-ray performed during LAAC is feasible and can improve the results of the procedure. Methods: The data presented here are from a retrospective single center study. Sample size was defined as 50 patients in which LAAC was performed without fusion imaging (control group) and 25 patients were the LAAC procedure was guided by fusion imaging (treatment group). Inclusion criteria were defined as age > 18 years and completion of an LAAC procedure defined as deployment of a WATCHMAN 2.5 LAA occluder. Study endpoints were procedure time, amount of used contrast medium, radiation dose, final position of the WATCHMAN in TEE (deviation from ideal positioning), and clinical endpoints, respectively. Results: LAA closure was successfully performed in all patients. No case of device embolism was occurring, and none of the patients experienced a periprocedural stroke/TIA nor a systemic embolism, respectively. Mean procedure time was 15 min shorter in the group of patients where fusion imaging was applied (p < 0.001). Additionally, the use of fusion imaging was associated with a significant reduction of contrast medium (20.6 ml less than in control; p < 0.045). Regarding the final position of the WATCHMAN, no relevant differences were found between the groups. Summary: The use of fusion imaging significantly reduced procedure time and the amount of contrast medium in patients undergoing LAAC. [ABSTRACT FROM AUTHOR]

Objectives: An immunotherapy was found to be effective in achieving long-term survival in some lung cancer patients. It has emerged to searching for new immune biomarkers for select the best candidates to this therapy. It is suggested that cancer stem cells (CSCs) are responsible for tumor initiation, maintenance and its metastatic potential. However, a role of CSCs in escape of cancer from immunosurveillance is unknown. The aim of the study was assess the phenotype of putative CSCs and to examine the expression of PD-L1 on CSCs in metastatic lymph nodes (LNs) in lung cancer patients. Material and Methods: Flow cytometry was used for CSCs evaluation in peripheral blood and EBUS/TBNA aspirates from N1,N2 lymph nodes in lung cancer patients. Results: Of 30 patients the LNs metastases were confirmed in 18 patients. We noticed presence of PD-L1 on putative lung CSCs- CD133 + EpCAM+ cells. A higher percentage of CD133 + EpCAM+PD-L1+ cells was observed in patients with metastatic in LNs- median value = 4.38% than in patients without LNs metastases– median value = 0,015% (p < 0.05). The highest proportion of PD-L1+ CSCs was found in adenocarcinoma patients and in those with oncogene addiction what indicate an particular biology of this type of lung cancer. Conclusion: The presence of CSCs with expression of PD-L1 in the metastatic LNs might suggest their immunogenic potential. EBUS/TBNA is commonly used in diagnosis and staging of lung cancer, so the analysis of the cells in metastatic LNs may fit in "immunoscoring" before immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Our previous work has shown peroxiredoxin-1 (PRDX1), one of major antioxidant enzymes, to be a biomarker in human breast cancer. Hereby, we further investigate the role of PRDX1, compared to its close homolog PRDX2, in mammary malignant cells.Methods: CRISPR/Cas9- or RNAi-based methods were used for genetic targeting PRDX1/2. Cell growth was assessed by crystal violet, EdU incorporation or colony formation assays. In vivo growth was assessed by a xenotransplantation model. Adenanthin was used to inhibit the thioredoxin-dependent antioxidant defense system. The prooxidant agents used were hydrogen peroxide, glucose oxidase and sodium L-ascorbate. A PY1 probe or HyPer-3 biosensor were used to detect hydrogen peroxide content in samples.Results: PRDX1 downregulation significantly impaired the growth rate of MCF-7 and ZR-75-1 breast cancer cells. Likewise, xenotransplanted PRDX1-deficient MCF-7 cells presented a retarded tumour growth. Furthermore, genetic targeting of PRDX1 or adenanthin, but not PRDX2, potently sensitised all six cancer cell lines studied, but not the non-cancerous cells, to glucose oxidase and ascorbate.Conclusions: Our study pinpoints the dominant role for PRDX1 in management of exogeneous oxidative stress by breast cancer cells and substantiates further exploration of PRDX1 as a target in this disease, especially when combined with prooxidant agents. [ABSTRACT FROM AUTHOR]

The reproductive activity of females of the Chinese pond mussel (Sinanodonta woodiana) was investigated in a European population inhabiting cooling water. The study used histological and stereological methods to determine gonad structure, changes in reproductive follicles during gametogenesis, oocyte development, glochidia structure, and brooding periods. Water in the channel of the “Dolna Odra” power plant did not freeze during the winter, and its mean annual temperature was 18.4°C. The population sex ratio was female biased (χ2 = 25.70, df = 1, P < 0.0001). Ovaries in mussels were formed by reproductive follicles. Previtellogenic and vitellogenic oocytes were attached to the follicle wall via the cytoplasmic stalk, and mature ovulated oocytes were present in the follicle lumen. Individuals with mature oocytes in gonads were present over the whole two-year study period, which indicates the continuous activity of gonads. Hooked glochidia had a larval thread. Females incubated the offspring in gill marsupia of outer demibranchs and were characterized by multiple tachytictic brooding periods. All gravid individuals presented mature and spent stages of gonadal development. The study provides the first direct information about the reproductive dynamics of this invasive species outside its original Asiatic range. [ABSTRACT FROM AUTHOR]

The first comprehensive spectroelectrochemical account of the behaviour of regioregular (RR-P3HT) and statistical (ST-P3HT) poly(3-hexylthiophenes) in solution is presented, in contrast to the many reports dealing with P3HT films merely deposited from solution. The conducted experiments revealed that the two types of P3HTs behave in sharply different ways upon the application of electrochemical stimuli: ST-P3HT readily precipitates at mildly oxidative potentials, while the precipitation of the RR-P3HT takes place to a much lesser extent, even at higher potentials. The two polymers, studied via UV-Vis-NIR-EPR spectroelectrochemistry, exhibited properties mostly in line with earlier reports. Further study revealed that RR-P3HT largely remains in solution, even in its doped form, whereas only traces of the doped ST-P3HT are observed in solution in identical conditions. The high concentration of the doped RR-P3HT in solution can be explained by its ability to form soluble polymer agglomerates, in which the positive charge of the p-doped chains is stabilised by and delocalised over neighbouring, interacting undoped chains. These conclusions are consistent with SEM micrographs, which show that after cycling the potential of the electrode in a solution of ST-P3HT, a uniform layer is formed, covering most of the surface of the electrode, whereas in the case of RR-P3HT surface coverage is marginal and formed layer has the appearance of veined blotches. Graphical abstract: [ABSTRACT FROM AUTHOR]

Background: Studies on the expression of thymidylate synthase (TS) in colorectal cancers (CRCs) have failed to provide unequivocal prognostic or predictive information. Here, we assessed the prognostic significance of TS expression in Astler-Coller stage B2 and C CRCs defined by a p21/p53 immunophenotype in patients subjected to 5-fluorouracil (5FU)-based adjuvant therapy. Methods: A cohort of 189 CRCs was asssessed for TS, p21 and p53 expression on tissue microarrays using immunohistochemistry, and associations with disease-free survival (DFS) and overall survival (OS) of the patients were assessed using univariate and multivariate analyses. Results: TS expression led to the stratification of patients with colon cancer, but not rectal cancer, with immunophenotypes other than p21+/p53- (referred to as P&P) into subgroups characterized by a worse (P&P TS+) and a better (P&P TS-) DFS and OS, in univariate ( P = 0.006 and P = 0.005, respectively) and multivariate ( P = 0.0004 and P = 0.002, respectively) analyses. The p21+/p53- immunophenotype was associated with a favorable prognosis, irrespective of TS expression. Conclusions: The strong association observed between the P&P TS+ immunophenotype and a worse DFS and OS suggests a predictive significance of TS expression for 5FU-based adjuvant therapy in patients with colon cancers exhibiting the P&P immunophenotype. In addition, our findings suggest that the appropriate target for assessment of TS expression as a prognostic/predictive marker is a subgroup of colon cancers with an immunophenotype other than p21+/p53-, and that only in this subgroup high TS expression is associated with an unfavorable DFS and OS. Therefore, we suggest that assessing TS expression in conjunction with p21/p53 immunophenotyping of colon cancers may improve the selection of patients suitable for 5FU-based adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Magnetic and magneto-transport properties of thin layers of the (Ga,Mn)(Bi,As) quaternary dilute magnetic semiconductor grown by the low-temperature molecular-beam epitaxy technique on GaAs substrates have been investigated. Ferromagnetic Curie temperature and magneto-crystalline anisotropy of the layers have been examined by using magneto-optical Kerr effect magnetometry and low-temperature magneto-transport measurements. Post-growth annealing treatment of the layers has been shown to enhance the hole concentration and Curie temperature in the layers. A significant increase in the magnitude of magneto-transport effects caused by incorporation of a small amount of Bi into the (Ga,Mn)As layers, revealed in the planar Hall effect (PHE) measurements, is interpreted as a result of enhanced spin-orbit coupling in the (Ga,Mn)(Bi,As) layers. A two-state behaviour of the planar Hall resistance at zero magnetic field provides its usefulness for applications in non-volatile memory devices. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) play an important role in the suppression of the immune response in lung cancer. Cytotoxic T-lymphocyte antigen 4 (CTLA-4) expressed on T lymphocytes is capable of downregulating cytotoxic T cells and is constitutively expressed on Tregs. Little is known about the population of Tregs with two forms of CTLA-4: surface (s) and intracellular (in) in the lung cancer environment. Th17 cells defined by production of IL-17 have pleiotropic functions in anticancer immune response. Our aim was to detect the elements of immune response regulation in lung cancer in three compartments: by analysis of bronchoalveolar lavage fluid (BALF) from the lung affected by cancer (clBALF), healthy symmetrical lung (hlBALF) and peripheral blood (PB) from the same patient. A total of 54 samples were collected. Tregs, (s)CTLA-4, (in)CTLA-4 were detected by flow cytometry with antibodies against CD4, CD25, Foxp3, CD127, CTLA-4, and concentration of IL-17 was estimated by ELISA. We observed a significantly higher proportion of Tregs in clBALF than in hlBALF or PB (8.5 vs. 5.0 vs. 5.1%, respectively, p < 0.05). The median proportion of (in)CTLA-4+ Tregs was higher in clBALF than in hlBALF or PB (89.0, 81.5, 56.0%, p < 0.05). IL-17 concentration was the highest in clBALF-6.6 pg/ml. We observed a significant correlation between the proportion of Tregs and (in)CTLA-4+ Tregs with IL-17A concentration in clBALF. We confirmed significant differences in the proportion of regulatory elements between cancerous lung and healthy lung and PB and the usefulness of BALF analysis in evaluation of immune response regulation in local lung cancer environment. [ABSTRACT FROM AUTHOR]

Germline mutations in BRCA1 were already linked to basal-like subtype of immunophenotypic molecular classification of breast cancer (BC). However, it is not known whether mutations in other BC susceptibility genes are associated with molecular subtypes of this cancer. We tested the hypothesis that distinct mutations in another BC susceptibility gene involved in DNA repair, i.e., CHEK2 may be associated with particular immunophenotypic molecular subtypes of this cancer. Two groups of patients: 1255 with BCs and 5496 healthy controls were genotyped for four CHEK2 mutations (I157T and three truncating mutations: 1100delC, IVS2 + 1G > A, del5395). BCs were tested by immunohistochemistry on tissue microarrays for ER, PR, HER-2, EGFR, and CK5/6 and were assigned to appropriate subtypes of immunophenotypic molecular classification. There was a significant association between CHEK2 mutations and the immunophenotypic molecular classification ( P = 0.004). CHEK2-associated cancers were predominantly luminal (108/117 = 92.3%). CHEK2-I157T variant was associated with the luminal A subtype ( P = 0.01), whereas CHEK2-truncating mutations were associated with the luminal B subtype ( P = 0.005). Comparing the prevalence of CHEK2 mutations in BC with controls revealed that carriers of an I157T variant had OR of 1.80 for luminal A subtype and carriers of truncating mutations had OR of 6.26 for luminal B subtype of BC. To our knowledge, this is the first study showing that specific mutations in the same susceptibility gene are associated with different immunophenotypic molecular subtypes of BC. This association represents independent evidence supporting the biological significance of immunophenotypic molecular classification of BC. [ABSTRACT FROM AUTHOR]

Despite ongoing trials of PARP inhibitors in the treatment of breast cancer (BC), the extent of poly(ADP-ribose)polymerase-1 (PARP-1) protein expression in BCs, which may influence treatment results, is not known. The purpose of this report is to assess expression of PARP-1 in BC including BRCA1-associated, triple negative (TN), and basal-like tumors. Immunohistochemistry with a PARP-1 antibody on tissue microarrays from 130 BRCA1-associated and 594 BRCA1-non-related BCs was used. The vast majority of breast carcinomas expressed high level of nuclear PARP-1 protein and a small percentage of tumors exhibited both nuclear and cytoplasmic PARP-1 expression. There was a significant difference between the mean nuclear PARP-1 quickscore in BRCA1-associated versus BRCA1-non-associated carcinomas in all tumors ( P < 0.0001), in the basal-like group ( P = 0.0086), TN ( P = 0.0015), and non-basal-like groups ( P = 0.016) but not in the non-TN group. Among BRCA1-associated BCs, low PARP-1 expression was found in 18.5% of all cases, 18.9% of basal-like and 21% of TN cancers. Among BRCA1-non-related tumors, low PARP-1 expression was found in 8.8% of all cases, 3.1% of basal-like, and 2.7% of TN cancers. PARP-1 expression is significantly associated with BRCA1 status in basal-like and TN BCs. The assessment of PARP-1 expression in tumor samples may improve the selection of BC patients for PARP inhibitor therapy. [ABSTRACT FROM AUTHOR]

In several, but not all, previous studies, positive p21(WAF1) expression has been suggested as an indicator of a good prognosis in patients with stage III/IV colorectal cancer. However, it is not known whether the same is true for stage B2 patients. The purpose of this study is to assess the influence of p21(WAF1) expression in tumor cells on disease-free survival (DFS) and overall survival (OS) of Astler-Coller stage B2 and C patients with colorectal cancer who underwent 5-fluorouracil-based adjuvant chemotherapy. Nuclear p21(WAF1) was detected by immunohistochemistry in tissue microarrays from 275 colorectal cancers. The expression of p21(WAF1) was associated with DFS (p = 0.025) and OS (p = 0.008) in the subgroup of stage B2 patients that was treated with adjuvant chemotherapy. In multivariate analysis, it remained the only independent prognostic parameter in relation to DFS and OS (p = 0.035 and p = 0.02, respectively). In the subgroup of 72 stage B2 patients with positive p21(WAF1) expression but not in the subgroup of 61 stage B2 patients with negative p21(WAF1) expression, adjuvant chemotherapy was associated with better DFS (85% 5-year survival versus 65% without chemotherapy, p = 0.03) and OS (96% versus 82%, p = 0.014). In the combined stage B2 and C group of patients treated with adjuvant chemotherapy, positive p21(WAF1) expression was also associated with better DFS and OS (p = 0.03, p = 0.002, respectively). Expression of p21(WAF1) in colorectal tumor cells identifies a subgroup of Astler-Coller stage B2 patients who could benefit significantly from 5FU-based chemotherapy and may improve the selection of patients for adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

The immunophenotypic predictive profile of BRCA1-associated cancers including major predictive markers, i.e., PARP-1, EGFR, c-kit, HER-2, and steroid hormones (ER/PR) that may have therapeutic relevance has not yet been reported in a comprehensive study. Using immunohistochemistry, we examined the expression of these proteins in a large cohort of BRCA1-associated breast cancers. PARP-1 immunoreactivity was found in 81.9%, EGFR in 43.6%, ER/PR in 17.9%, c-kit in 14.7%, and overexpression of HER-2 in 3.6% of cancers. For all markers studied, 8.2% of tumors were negative. Expression of only one predictive marker was found in 29.7% of cancers, and most frequently, it was PARP-1 (20.8%). In 62.1% of tumors, more than one predictive marker was expressed: PARP-1 and EGFR in 30.4%, PARP-1, and hormone receptors in 13.3% and PARP-1 with c-kit in 7.5% of all tumors. Coexpression of two or more other predictive markers was rare. There were significant differences in the median age at diagnosis of BRCA1-associated cancer between patients with ER+ vs. ER- and grades 1-2 vs. grade 3 tumors. These results demonstrate that BRCA1-associated cancers differ with respect to expression of proteins that are regarded as targets for specific therapies and that 92% of patients with BRCA1-associated cancers may benefit from one or several options for specific therapy (in addition to DNA damaging agents, e.g., cisplatin). About 8% of cancers which do not express therapeutic target proteins may not respond to such therapies. Knowledge of the immunophenotypic predictive profile may help with the recruitment of patients for trials of targeted therapies. [ABSTRACT FROM AUTHOR]

Colorectal carcinoma (CRC) is a heterogeneous disease with specific epidemiological, pathological, molecular, and clinical characteristics that depend on the location of the tumor relative to the splenic flexure. Thymidylate synthase (TS) is a major target of 5-fluorouracil-based chemotherapy for CRC and high expression of this enzyme in tumor cells can influence the effect of therapy. We examined differences in TS protein expression in nuclei of tumor cells between CRCs located proximal and distal to the splenic flexure. Nuclear TS was detected by immunohistochemistry with a TS 106 monoclonal antibody on tissue microarrays constructed from 269 CRCs. The median histological score of nuclear TS expression of all proximal tumors was two times higher (p = 0.0003) and in men three times higher (p = 0.00023) than that found in distal tumors. In multivariate analysis which included age, sex, Astler-Coller stage, histological grade, and site, only proximal location of the tumor was identified as an independent factor associated with higher TS expression (odds ratio 2.46, 95% confidence interval = 1.29-4.70, p = 0.0062). These results demonstrate significant differences in nuclear TS expression between proximal and distal cancers and suggest the potential importance of the site of the tumor for proper stratification of patients for chemotherapy. [ABSTRACT FROM AUTHOR]

Five and six heterocycle ring assemblies, comprising triazole or oxadiazole acceptor (A) units and thiophene or alkylthiophene donor (D) units in a DDADD and DDAADD arrangement, have been synthesised and characterised by spectroscopic and electrochemical means. It is demonstrated that the replacement of a weaker acceptor (triazole) by a stronger one (oxadiazole) in DDADD compounds results in lowering of the frontier molecular energy gap by 70 meV from 2.94 to 2.87 eV. For oxadiazole-centred compounds these gaps can be further lowered by increasing the number of A units and alkyl solubilising substituents, down to 2.76 eV for the DDAADD compound containing four alkyl pendants. The photoluminescence quantum yield exceeds 50 % for DDADD compounds and reaches 78 % for DDAADD ones. All compounds, when dispersed in a blend consisting of 70 % poly(vinylcarbazole) (PVK) and 30 % of 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole (PBD) (host-guest configuration), demonstrate light-emitting diode behaviour, affording blue, tuneable emission with luminances reaching 120 cd m and luminous efficiencies of 0.12 cd A for non-optimised devices. [ABSTRACT FROM AUTHOR]

The p21/WAF1/Cipl antibody, DCS-60, was characterized by means of immunoblotting and immunofluorescence on a variety of human breast cancer cell lines. Heterogeneous staining of nuclei was observed with strong staining of cells in early G1. p21/WAF1/Cipl expression in invasive ductal, not otherwise specified breast carcinomas was determined using immunohistochemistry with this antibody and computerized image analysis. Two hundred and twenty-two tumors, including 130 from patients with no axillary node involvement, were examined. p21-positive tumor cell nuclei were found in 30% of the breast carcinomas. The percentage of tumor cell nuclei that were positive ranged from less than 1% to greater than 10%. In the whole cohort of patients, p21 expression was significantly associated with a low histological grade. In the node-negative group, there was a significant negative correlation between p21 positivity and a high (>10%) MIB-1 score. The mean MIB-1 score was significantly lower in p21-positive tumors in the whole cohort of patients (P=0.03) and in the nodenegative group (P=0.02). No association was found between p21 expression and overall survival at 5 years. With respect to p21/p53 phenotype, the significant difference in survival was noted only for the group of patients treated with adjuvant chemotherapy. The p21- p53+ phenotype had the worst survival (58% surviving 5 years), while the p21+ p53- phenotype had good survival (83% surviving 5 years; P<0.05). The results seem to suggest a correlation between p21/p53 phenotype and response to adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of a novel polypyrrole material grafted with biodegradable oligo-3-hydroxybutyrate pendants. The polymer was prepared in a two-step process. Firstly, the potassium salt 1-(2-carboxyethyl)pyrrole was reacted with β-butyrolactone affording N-substituted macromonomer. Secondly, the macromonomer was oxidatively polymerised with FeCl Lewis acid. The reaction was carried out in solvents of assorted polarity: dimethylsulphoxide, acetonitrile, dimethylformamide and water. Obtained polymers have been characterised comprehensively using a suite of spectral techniques. The material was found to combine the well-known merits of 3-hydroxybutyrate polymers with the electrical conductivity imparted by polypyrrole units. [ABSTRACT FROM AUTHOR]

We have studied the influence of the beryllium doping on strain in the II-type InAs/GaSb superlattices (SLs) by means of high-resolution X-ray diffraction (HRXRD). Three analyzed superlattices were grown by molecular beam epitaxy. One of the examined superlattices was undoped. Two others structures, called doped SLs, composed of two superlattices: Be-doped and undoped which were grown one on the top of each other. The doping concentration was determined by secondary ion mass spectroscopy. The doping level was 1×10 cm and 2×10 cm. For doped superlattices, the HRXRD measurements showed splitting of satellite (ST) peaks. Furthermore, the separation of ST peaks increase with doping level. In contrast, for undoped superlattice, the splitting of the ST peaks was not observed. Sometimes the separation of ST peaks can be caused by change of thickness period of superlattice or partial relaxation of the structure. However, we claim that in our experiment the splitting is caused by another mechanism: The presence of Be atoms in SL causes the change of average lattice constant of the superlattice. The influence of Be dopant on lattice parameter of superlattice was confirmed by theoretical simulations. Furthermore, the change of the lattice constant (Δ a/ a) of the GaSb:Be buffer was examined. The reduction of lattice parameter of GaSb was noticed. It was caused by the presence of Be doping and unintentionally incorporated As-atoms in the GaSb layer. It is very important to know that even very small Be concentration (1×10 cm) causes the change of average lattice parameter of SL. [ABSTRACT FROM AUTHOR]

Epitaxial layers of (Ga,Mn)As ferromagnetic semiconductor have been subjected to low-energy ion implantation by applying a very low fluence of either chemically active, oxygen ions or inactive ions of neon noble gas. Several complementary characterization techniques have been used with the aim of studying the effect of ion implantation on the layer properties. Investigation of their electrical and magnetic properties revealed that implantation with either O or Ne ions completely suppressed both the conductivity and ferromagnetism in the layers. On the other hand, Raman spectroscopy measurements evidenced that O ion implantation influenced optical properties of the layers noticeably stronger than did Ne ion implantation. Moreover, structural modifications of the layers caused by ion implantation were investigated using high-resolution x-ray diffraction technique. A mechanism responsible for ion-implantation-induced suppression of the conductivity and ferromagnetism in (Ga,Mn)As layers, which could be applied as a method for tailoring nanostructures in the layers, is discussed in terms of defects created in the layers by the two implanted elements. [ABSTRACT FROM AUTHOR]

Spatially resolved X-ray diffraction (SRXRD) is used for micro-imaging of strain in GaAs:Si layers grown by liquid phase epitaxial lateral overgrowth (ELO) on SiO2-masked GaAs substrates. We show that laterally overgrown parts of the layers (wings) are tilted towards the underlying mask. By SRXRD mapping local wing tilt is easily distinguished from macroscopic sample curvature. The direction of the tilt and distribution of tilt magnitude across the width of each layer can also be readily determined. This allows measuring of the shape of the lattice planes in individual ELO stripes. Downward wing tilt disappears completely when the mask is removed by selective etching. Then residual strain in ELO layers is exposed. In particular, upward tilt is found in free-standing ELO wings. Numerical simulations show that this phenomenon is caused by different concentrations of silicon dopant in vertically and laterally grown parts of the layer. [ABSTRACT FROM AUTHOR]

As a development of our previous analysis of a single GaAs stripe, in this work spatially resolved X-ray diffraction (SRXRD) was applied for micro-imaging of strain in partially and fully overgrown GaAs layers grown by epitaxial lateral overgrowth (ELO) on SiO2-masked GaAs substrates. We show that a standard X-ray diffraction providing information integrated over many stripes leads to overestimation of lattice misorientation in such samples. On the contrary, the SRXRD allows precise measurements of local wing tilts of individual ELO stripes with micrometer-scale spatial resolution. A complex strain field was found in fully overgrown GaAs ELO samples. With the use of the SRXRD technique, the distribution of this strain was measured that allowed reproducing the shape of deformed lattice planes both inside the epitaxial layer as well as in the substrate underneath. [ABSTRACT FROM AUTHOR]

The effect of high-temperature annealing at high hydrostatic pressures on photoluminescence of heavily doped GaAs:Be layers grown by molecular-beam epitaxy on GaAs substrates was studied. A blue shift of the band-edge luminescence line and an increase in the relative intensity of the shoulder at the high-energy wing of this line were detected after annealing in the spectra of layers with a beryllium atom concentration higher than 5 × 10[sup 19] cm[sup –3]. The same layers featured a concentration-related decrease in the GaAs lattice parameter, which does not conform to the Vegard law. These effects can be attributed to the formation of beryllium inclusions in heavily doped GaAs. Due to different compressibility and thermal expansion coefficients of Be inclusions and GaAs, high-temperature and high-pressure treatment gives rise to structural defects; hence, the probability of transitions that are indirect in the k space increases. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Demonstrates that bovine articular chondrocytes cultured in low oxygen tension respond to interleukin-1Β by an increased DNA binding activity of NF-ΚB and AP-1 transcription factors. Effect of normoxia and hypoxia on interleukin-1Β-induced NF-ΚB and AP-1 DNA binding; Effect of rhein on interleukin-1Β-induced NF-ΚB and AP-1 activation.

This paper provides data concerning biochemical composition of milt of two sturgeon species, Siberian sturgeon bred in aquaculture facility of Inland Fisheries Institute in North Poland and sterlet (from two different populations from Danube and Odra). Milt plasma of Siberian sturgeon and sterlet, when compared to teleost fish, is characterized by much lower osmolality (up 70 to 96 mOsm kg−1) and protein concentration (0.24–0.58 g l−1). In spite of the presence of an acrosome and acrosin the antiproteinase activity of seminal plasma was low (12.79–25.40 U l−1). Activities of arylsulfatase and β-N-acetylglucosaminidase were found in spermatozoa. This agrees with the presence of an acrosome in sturgeons sperm. Similarly to mammals, these enzymes are also present in milt plasma. We determined a range of enzymatic activities from the minimal (seminal plasma) to the maximal damage (supernatants obtained after freezing-thawing without cryoprotectant). Activities of arylsulfatase, β-N-acetylglucosaminidase, lactic dehydrogenase and acid phosphatase were released from spermatozoa after freezing-thawing. For this reason they are good potential candidates as a markers of cryoinjury to sperm acrosome and midpiece. [ABSTRACT FROM AUTHOR]

Biosensors provide a sophisticated and discriminating means of probing biomolecular interactions. Specific ligands such as peptides and proteins can be immobilized onto sensor surfaces by a number of means including covalent attachment via amine, thiol or aldehyde chemistry, capture via biotin-avidin interaction or the use of specific tags. We have devised a simple chemoselective ligation method to selectively conjugate an anchoring functionality onto N-terminal serine or threonine residues of peptides and proteins allowing them to be immobilised onto the sensor surface in a defined orientation. It is based on the specific reaction of the 1,2-aminothiol of cysteine with an aldehyde under acidic conditions to form a stable thiazolidine product. The carbonyl precursors are derived from the 1,2-aminoalcohols of Ser or Thr that can be selectively and rapidly converted to the aldehyde form by periodate oxidation. Biotinylation of the aldehyde is then achieved via simple conjugation with a novel water-soluble dipeptide that contains a lysine residue bearing an Nε-cysteine-derived 1,2-aminothiol and an Nα-biotin moiety. Use of this method allowed selective biotinylation of a native form of murine EGF (mEGF) that has an N-terminal serine residue. This derivative was then immobilised onto a streptavidin biosensor surface, and the resultant surface activity compared with those obtained by immobilising recombinant human EGF or the soluble extracellular domain of the EGF receptor (sEGFR) using amine coupling (NHS/EDC) chemistry.The surface recognised the recombinant sEGFR with a similar K to that of human EGF immobilised using NHS/EDC chemistry, or if the receptor was immobilised and murine EGF injected. [ABSTRACT FROM AUTHOR]

Double-crystal and triple-axis x-ray diffractometry and transmission electron microscopy are used to characterize the microstructure, strain, and composition of InGaN layers grown on GaN by metalorganic chemical vapor deposition (MOCVD). Three different samples with increasing In concentration have been studied, all grown on GaN deposited on sapphire either with GaN or AlN buffer layers. It was found that InGaN layers with nominal 28% and 40% InN content consist of two sub-layers; the first sub-layer is pseudomorphic with the underlying GaN with lower In content than nominal. The top sub-layer is fully relaxed with a high density of planar defects and In content close to the nominal value. This is in contrast to a common assumption applied to InGaN quantum wells that ‘quantum-dot like areas’ are formed with different In content. The sample with the nominal indium concentration of 45% does not exhibit any intermediate strained layer, is fully relaxed and the In concentration (43.8%) agrees well with the nominal value. [ABSTRACT FROM AUTHOR]

We examined 59 breast cancers for p53 and bcl-2 protein expression by immunohistochemistry. The results were correlated with Ki-67 immunostaining. p53-negativity was noted in 40 cases and the remaining 19 tumours were p53-positive. Thirty-six tumours showed strong expression of bcl-2 and in 23 no staining for this protein was observed. We found statistically significant reverse correlation between expression of p53 and bcl-2 in majority of carcinomas: 31 cases were bcl-2 positive and p53-negative, and 14 tumours were bcl-2-negative and p53-positive. Six carcinomas showed no nuclear staining for Ki-67 and in the remaining 53 the percent of cancer cells positive for Ki-67 ranged from 1 to 60 (mean: 14.6). In these 53 cases we found that bcl-2-positive tumours were characterized by lower proliferation than bcl-2-negative tumours, the mean value of Ki-67 immunostaining being 10.7% and 23.0%, respectively. p53-negative tumours showed lower proliferation than p53-positive tumours: mean Ki-67 index was 10.2% and 23.9%, respectively. We conclude that immunohistochemically detected p53 and bcl-2 proteins show a significant inverse relationship in majority of breast carcinomas and their expression correlates with tumour proliferation (Ki-67 immunostaining). [ABSTRACT FROM AUTHOR]

Vimentin, p53 protein and cathepsin D positivity were assessed by immunohistochemistry, and oestrogen receptor (ER) by an enzyme immunoassay, in invasive lobular carcinomas (LC) of the breast. While vimentin was positive in only 5% (3/57) and p53 protein was positive only in 3% (2/63), cathepsin D was expressed in 86% (48/56) and ER in 78% (25/32). Classical LC were negative for p53 protein and all except one were cathepsin D positive. These results are in contrast to invasive ductal breast carcinomas (DC), where the reported average incidence of vimentin and p53 protein is much higher (19% and 33% respectively) and that of cathepsin D and ER lower (63% and 67% respectively). Thus lack of expression of vimentin and lack of p53 positivity together with high incidence of expression of cathepsin D and ER are more often associated with lobular than with ductal differentiation of invasive breast cancer. The results show that LC, distinguished morphologically, can further be defined by its immunohistochemical profile. This in turn may point to underlying biological differences between LC and DC. [ABSTRACT FROM AUTHOR]

The proliferative activity of crypt epithelial cells was studied in 64 duodenal biopsies using immunohistochemistry and proliferating cell nuclear antigen (PCNA)/cyclin monoclonal antibodies in alcohol-fixed paraffin-embedded sections. A positive correlation between duodenitis as defined by histological criteria and increased mean percentage of PCNA positive crypt cell nuclei (PCNA index) was found. The mean PCNA index in normal mucosa was 11.8±2.7% (mean ± SD), in mild (grade 1) duodenitis 17.3±3.9%, in moderate (grade 2) 30.6±6.9%, and in severe (grade 3) duodenitis 41.1±8.5%. The inclusion of PCNA index, which is easily measured in paraffin-embedded sections, in the existing histopathological grading systems of duodenitis may improve their clinical relevance. [ABSTRACT FROM AUTHOR]

Surface configuration of mesothelial cells identified by light microscopy (LM) has been studied by scanning electron microscopy (SEM). It has been shown that mesothelial cells may have a variable SEM appearance. The surfaces of a small proportion of mesothelial cells are covered by regular microvilli (MV) and show openings of the pinocytotic vesicles. The surfaces of the majority of these cells are covered by vesicles or blebs. An intermediate population of mesothelial cells, i.e., cells displaying side-by-side blebs and MV, has also been observed. The latter cells no longer display pinocytotic vesicles. Occasional mesothelial cells have smooth surfaces. It has been shown by LM and transmission electron microscopy that cells with blebs are viable and capable of mitotic activity. It is concluded that mesothelial cells, detached from their epithelial setting, lose microvilli and pinocytotic vesicles and acquire surface blebs. The possible relationship between mesothelial cells and macrophages based on surface features has been discussed. [ABSTRACT FROM AUTHOR]

The surfaces of viable cells of metastatic human carcinomas of various histologic types and primary origin, suspended in pleural and ascitic fluids, were shown by scanning electron microscopy to be covered by microvilli of variable configuration and distribution. Microvilli of some cancer cells appeared biologically active since they were capable of forming extensions and anastomoses when settling on glass. The possible specificity and significance of microvilli in the light of the experimental data were discussed. [ABSTRACT FROM AUTHOR]

The paper reports on the changes of lattice parameters by free electrons (via deformation potential of the conduction band minimum) and by point defects (via size effect) for gallium nitride. The measurements were performed on single crystals grown at about 15 kbar and 1800 K and on homoepitaxial layers using high-resolution X-ray diffraction methods at temperatures 40-770 K. It was found that a high free-electron concentration increase both, the lattice parameters and thermal expansion. It was observed that most of the single crystals of gallium nitride possess different lattice parameters on their two sides and this difference increases at high temperature. The experimental results of X-ray diffraction, electron microscopy and Hall measurements served for creating a model of generation of low-angle boundaries in the pressure-grown single crystals. [ABSTRACT FROM AUTHOR]

It has been shown that an experimental 4 wt pet Mn steel can be successfully treated to produce a very high surface hardness (in excess of 700 VPN) and a substantial core strength. The base steel has sufficient hardenability to give through-hardening without quenching from the carburization furnace. [ABSTRACT FROM AUTHOR]

The article "Fusion Imaging of X-ray and Transesophageal Echocardiography Improves the Procedure of Left Atrial Appendage Closure." [ABSTRACT FROM AUTHOR]

Abstract The NOD2 gene has been associated with susceptibility to Crohns disease, and more recently with carcinoma of the colon as well. NOD2 is involved in the inflammatory response and the activation of the NFkB pathway. The range of cancer types associated with NOD2 has not been well studied. The 3020insC allele results in a truncated NOD2 protein and is present in approximately 7% of the population. We studied a possible association between the 3020insC allele of the NOD2 gene and breast cancer using 462 cases and 1910 controls from Poland. Patients were diagnosed with invasive breast cancer at are of two Szczecin regional hospitals between 2002 and 2004. Pathology specimens were reviewed for histological subtype and for the presence of ductal carcinoma in situ (DCIS). Overall there was no association between breast cancer and NOD2 (OR=1.1; p =0.76), but significant associations were observed between the presence of the allele and early-onset breast cancer (OR=1.9; p =0.01) and between the allele and ductal breast cancer with an in situ component (OR=2.2; p =0.006). [ABSTRACT FROM AUTHOR]