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Studies of cell development in artificial microenvironments can contribute to understanding a series of physiological mechanisms that might be influenced by geometrical features of the microenvironment itself. In this work we applied two-photon polymerization to fabricate threedimensional microenvironments composed of a matrix arrangement of microstructures (circular and square cross-sections pillars) with distinct spacing. Such microenvironments were used to evaluate the growth of Michigan Cancer Foundation-7 (MCF-7) cells that are commonly used as a model system to investigate fundamental aspects of the tumor biology. Our results reveal that the cell density decreases as the distance between structures in the environment is increased. Additionally, cell growth shows slightly better results for the microenvironments composed of circular crosssection structures. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Hydrocarbon reservoirs are generally located beneath complex geological structures. Frequently, such areas contain seismic diffractors that carry detailed structure information in the order of the seismic wavelength. Therefore, the development of computational facilities capable of detecting diffractor points with a good resolution is desirable but has been a challenge in the area of seismic processing. In this work, we present a method for the detection of diffraction points in the common-offset-gather domain. The method applies a two-class k nearest neighbours (kNN) pattern recognition technique to amplitudes along diffraction traveltime curves to distinguish between diffractions and reflections or noise. While the method, in principle, requires knowledge of the migration velocity field, it is very robust with respect to an erroneous model. Numerical examples using synthetic seismic and field ground-penetrating-radar (GPR) data demonstrate the feasibility of the technique and show its usefulness for automatically mapping diffraction points in a seismic section. In our applications, the method was able to detect all diffractions present in the data and did not produce any false positives. [ABSTRACT FROM AUTHOR]

The fungus Pochonia chlamydosporia is currently one of the most studied biological control agents for its great potential in management of root-knot nematode. The objective of this study was to evaluate the efficiency of a biological product, at the development phase, based on the fungus P. chlamydosporia, isolate Pc-10, for the control of Meloidogyne javanica on lettuce and carrot at the field level. Rizoflora Biothecnology Inc. had the special temporary registration for field application of Pc-10 isolate for agronomic efficiency tests. The experiment was arranged in a randomized block design with eight replicates per treatment. Each experimental plot was 2 m2. The treatments consisted of the doses 0.0, 3.0, 3.8, 4.5 or 9.5 g of rice colonized with P. chlamydosporia and dried, /m2 of experimental plot. Fifteen days after the incorporation of the product 21-d-old lettuce seedlings of the cultivar 'Babá de verão' were transplanted into each experimental plot, and the experiment was conducted for 50 d. The doses of 3.8 and 9.5 g of the product reduced the number of galls in 46.0% and 38.9% on the roots, and the number of nematode eggs in the soil by 52.3% and 53.1%, respectively. All treatments enhanced the development of the lettuce plants, compared with the control treatment. After the lettuce harvest, doses of 0, 25, 50, 75 and 100 g of product /m2 were applied, with the plot position of the new doses, lowest to highest corresponding with the doses in the previous experiment. After 15 d, the plots were seeded with carrot 'Nantes superior'. At all of the doses, including the control treatment, low numbers of galls were observed on the roots of the carrots, without significant differences between the treatments. No statistical differences were observed for the development of plants. [ABSTRACT FROM AUTHOR]

Less invasive and more effective cancer treatments have been the aim of research in recent decades, e.g. photothermal tumour ablation using gold nanorods. In this study we investigate the cell death pathways activated, and confirm the possibility of CTAB-coated nanoparticle use in vivo. Nanorods were synthesized by the seeding method; some of them were centrifuged and washed to eliminate soluble CTAB. The MTT cytotoxicity test was performed to evaluate cytotoxicity, and the particles' viability after their synthesis was assessed. Once it had been observed that centrifuged and washed nanorods are harmless, and that nanoparticles must be used within 48 h after their synthesis, in vivo hyperthermic treatment was performed. After irradiation, a tumour biopsy was subjected to a chemiluminescence assay to evaluate membrane lipoperoxidation, and to a TRAP assay to evaluate total antioxidant capacity. There was a 47 °C rise in temperature observed at the tumour site. Animals irradiated with a laser (with or without nanorods) showed similar membrane lipoperoxidation, more intense than in control animals. The antioxidant capacity of experimental animal tumours was elevated. Our results indicate that necrosis is possibly the cell death pathway activated in this case, and that nanorod treatment is worthwhile. [ABSTRACT FROM AUTHOR]

Copyright of Lua Nova is the property of CEDEC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A water soluble polysaccharide and its selective precipitated fractions (Fl, F2, and F3) were isolated from hot water extract of fruiting bodies of Agaricus blazei Murril known as Agaricus brasiliensis to evaluate the analgesic activity of the materials in Swiss mice. The isolated material and its fractions were characterized by two-dimensional COSY and HMQC spectra as β-(1 → 6)-α-(1 → 4)-glucan-bound-protein polysaccharide constituted mainly by β-(1 → 6) glucan. The glucan-protein polysaccharide and its fractions were analyzed in relation to the protein, carbohydrate, and mineral elements contents. The analysis of the glucan-protein complex revealed a total carbohydrate content of 36.95% and protein conjugated content of 17.24%. The mineral elements found in larger proportion were K, Na, Ca, P, and Zn. The analgesic activity bioassay of the β-(1 → 6)-α-(l → 4)-glucan bound-protein polysaccharide and its fractions in Swiss mice indicated a significant effect. [ABSTRACT FROM AUTHOR]

Breast cancer is the malignant neoplasia with the highest incidence in women worldwide. Chronic oxidative stress and inflammation have been indicated as major mediators during carcinogenesis and cancer progression. Human studies have not considered the complexity of tumor biology during the stages of cancer advance, limiting their clinical application. The purpose of this study was to characterize systemic oxidative stress and immune response parameters in early (ED; TNM I and II) and advanced disease (AD; TNM III and IV) of patients diagnosed with infiltrative ductal carcinoma breast cancer. Oxidative stress parameters were evaluated by plasmatic lipoperoxidation, carbonyl content, thiobarbituric reactive substances (TBARS), nitric oxide levels (NO), total radical antioxidant parameter (TRAP), superoxide dismutase, and catalase activities and GSH levels. Immune evaluation was determined by TNF-α, IL-1β, IL-12, and IL-10 levels and leukocytes oxidative burst evaluation by chemiluminescence. Tissue damage analysis included heart (total CK and CKMB), liver (AST, ALT, GGT), and renal (creatinine, urea, and uric acid) plasmatic markers. C-reactive protein (CRP) and iron metabolism were also evaluated. Analysis of the results verified different oxidative stress statuses occur at distinct cancer stages. ED was characterized by reduction in catalase, 8-isoprostanes, and GSH levels, with enhanced lipid peroxidation and TBARS levels. AD exhibited more pronounced oxidative status, with reduction in catalase activity and TRAP, intense lipid peroxidation and high levels of NO, TBARs, and carbonyl content. ED patients presented a Th2 immune pattern, while AD exhibited Th1 status. CRP levels and ferritin were increased in both stages of disease. Leukocytes burst impairment was observed in both the groups. Plasma iron levels were significantly elevated in AD. The data obtained indicated that oxidative stress enhancement and immune response impairment may be necessary to ensure cancer progression to advanced stages and may result from both host and tumor inflammatory mediators. [ABSTRACT FROM AUTHOR]

Several adverse effects of chemotherapy treatments have been described, and most of these effects are associated with direct interactions between blood cells and indirect effects generated during the oxidative metabolism of antineoplastic drugs. In this study we evaluated the oxidative systemic status and hematological profiles of breast cancer patients with advanced ductal infiltrative carcinoma treated with doxorubicin (DOX) or paclitaxel (PTX) within 1 h after chemotherapy. Blood analyses included evaluation of hemogram, pro-oxidative markers, and antioxidant status. The results showed that advanced breast cancer diseased (AD) patients without previous chemotherapy presented anemia and high oxidative stress status characterized by elevated levels of lipid peroxidation and nitric oxide, and reduced catalase activity when compared with controls. DOX-treated patients exhibited increased anemia and reduced antioxidant status, which was revealed by decreases in reduced glutathione levels and the total antioxidant capacity of plasma; however, these changes did not lead to further increases in lipid peroxidation or carbonyl proteins when compared with the AD group. PTX-treated patients also showed increased anemia, lactate dehydrogenase leakage, and enhanced lipid peroxidation. These data reveal for the first time that patients subjected to chemotherapy with DOX or PTX present immediate systemic oxidative stress and red blood cell oxidative injury with anemia development. These findings provide a new perspective on the systemic redox state of AD and patients subjected to chemotherapy regarding oxidative stress enhancement and its possible involvement in the aggravation of chronic anemia. [ABSTRACT FROM AUTHOR]

This study investigated the prevalence of adeno-associated virus (AAV) and human papillomavirus (HPV) DNA in cervical samples of HIV-seropositive and -seronegative women attending a clinic in south-eastern Brazil. Both viruses were investigated by polymerase chain reaction (PCR) and cytological exams were performed. AAV was typed by PCR and restriction fragment length polymorphism analysis. AAV prevalence was 19.7% (56/284), with 18.7% (21/112) and 20.3% (35/172) in HIV-positive and -negative women, respectively. AAV type 2 was the single virus type detected. AAV was detected with higher frequency in HPV- infected women (P < 0.05) as was HPV in HIV-positive women (P < 0.05). The AAV-HPV co-infected women showed a lower rate of atypical squamous cells of undetermined significance or cervical intraepithelial neoplasia development compared with those infected only with HPV. The prevalence of AAV2 confirms this type as the most common in human samples. This is the first report examining AAV in cervical samples of HIV-infected women and indicates that HIV infection does not appear to influence AAV prevalence or AAV-HPV co-infection. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effect of incorporation of petroleum coke in the physical and mechanical properties of red ceramic. The study determines the formation of rectangular specimens by extrusion to fire at 850 and 1050 °C. It notes that flexural strength and absorption of water were determined along with the microstructure of the fired ceramics. It also mentions the reduction of energy consumption throughout the firing stage due to the petroleum coke waste.