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Abstract: Advances in structural and biochemical properties of carmovirus movement proteins (MPs) have only been obtained in p7 and p9 from Carnation mottle virus (CarMV). Alignment of carmovirus MPs revealed a low conservation of amino acid identity but interestingly, similarity was elevated in regions associated with the functional secondary structure elements reported for CarMV which were conserved in all studied proteins. Nevertheless, some differential features in relation with CarMV MPs were identified in those from Melon necrotic virus (MNSV) (p7A and p7B). p7A was a soluble non-sequence specific RNA-binding protein, but unlike CarMV p7, its central region alone could not account for the RNA-binding properties of the entire protein. In fact, a 22-amino acid synthetic peptide whose sequence corresponds to this central region rendered an apparent dissociation constant (K d) significantly higher than that of the corresponding entire protein (9 mM vs. 0.83–25.7 μM). This p7A-derived peptide could be induced to fold into an alpha-helical structure as demonstrated for other carmovirus p7-like proteins. Additionally, in vitro fractionation of p7B transcription/translation mixtures in the presence of ER-derived microsomal membranes strongly suggested that p7B is an integral membrane protein. Both characteristics of these two small MPs forming the double gene block (DGB) of MNSV are discussed in the context of the intra- and intercellular movement of carmovirus. [Copyright &y& Elsevier]

Summary: Pregnant goats were inoculated subcutaneosly with Coxiella burnetii and the course of infection was studied. Abortion in the last third of pregnancy occurred in all infected animals. Tissues from the placenta and other organs were studied before and after abortion by immunohistochemistry and PCR analysis. After infection, mild lesions were observed in several maternal organs, mainly the mammary gland but also the lung and the liver. The trophoblast cells of the choriallantoic membrane were the first target cells of the placenta; there was, however, a substantial delay between initial infection and placental colonization. In the last weeks of pregnancy, just before abortion, massive bacterial multiplication was detected in the placenta. In this stage of infection a necrotic and suppurative placentitis separated the fetal trophoblast cells from maternal syncytial epithelium. Vasculitis was observed in the fetal mesenchyme. A strong maternal T-cell response was detected in the inter-placentomal areas but not in the placentomes, where only neutrophils and smaller numbers of macrophages were associated with the lesions. Neither lesions nor C. burnetii DNA were found in maternal organs in animals maintained until day 120 post-abortion. [Copyright &y& Elsevier]

Copyright of Boletin Intexter del Instituto de Investigacion Textil y Cooperacion Industrial Terrassa is the property of Universitat Politecnica de Catalunya 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.)

Summary: The role of the specific cellular immune response is well established in Chlamydiaceae infections, but the importance of each T-cell subset seems to be species-dependent. This study was designed to clarify the role of T-cell subsets in the response to Chlamydophila abortus primary infection. C57BL/6 mice were depleted of CD4+or CD8+, or both, by monoclonal antibody injections and subsequently infected with C. abortus. Mice were killed at intervals and samples were collected for bacteriological and histopathological analysis. Also carried out were spleen cell culture, cytokine quantification, immunolabelling for C. abortus antigen, and a TUNEL assay for apoptosis. CD8+ T cell-depleted mice all died within 12 days of C. abortus infection, while no mortality was observed in the other groups; surprisingly, CD4+ T cell-depleted mice showed lower morbidity (expressed as weight loss) than did a non-depleted (control) group. CD8+ T cell-depleted mice also differed from the other groups in showing a significantly higher chlamydial burden in the liver. CD8+ T cell-depleted mice also had a higher number of apoptotic cells in hepatic inflammatory foci and showed exacerbated IFN-γ production by spleen cells after specific stimulation. Simultaneous depletion of both T-cell subpopulations led to a chronic infection, but not to early mortality. It is concluded that CD8+ T cells may play a role in the regulatory control of the CD4+ T-cell response and may have a direct cytotoxic or IFN-γ-mediated effect on infected cells. [Copyright &y& Elsevier]

Copyright of Boletin Intexter del Instituto de Investigacion Textil y Cooperacion Industrial Terrassa is the property of Universitat Politecnica de Catalunya 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.)

Two methods were used to apply self-absorption corrections for the determination of beta radioactivity in water samples (either for an identified radionuclide or for monitoring trends). One method was performed by estimating the absorption coefficient by assuming an exponential behaviour of absorption using external absorbers, while the other method was performed by preparing empirical curves using standards of different mass. In the first method, a relationship between absorption coefficient and maximum beta energy was also derived. In the second method, self-absorption curves for 90Sr/90Y standard were prepared with several sodium salts (carbonate, nitrate and sulphate salts) and, for 40K standard using a potassium salt. Both beta emitters are usually necessary to calibrate detectors for beta radioactivity measurements. This study showed that, for 90Sr/90Y, results using standards of different mass were more accurate than using external absorbers. Furthermore, it is highly recommended to melt sodium nitrate salts in order to perform a self-absorption curve for 90Sr/90Y because standards were stable in time and homogeneously distributed. For 40K, a self-absorption curve may be easily derived using paper absorbers of different thickness, instead of performing a time consuming self-absorption curve using a set of varying thickness of 40K standards. In order to test the two methods, the gross beta activity of several environmental water samples was analysed. [Copyright &y& Elsevier]

High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method. [Copyright &y& Elsevier]

The development of new chemical structures for dyes is currently aimed at seeking products of lower ecological impact that conserve or even improve on the dying properties and level of quality. Recently, attention has been paid to amphiphilic structures that meet the needs of textile technology and show low toxicity and high biodegradability. In this work we synthesised disperse dyes that, in addition to the traditional azoic chromophoric system, contain glucosydic replacements in their structure whose hydrophilic nature should lead to greater biodegradability. The dyeing behaviour and final fastness of these dyes was analysed on polyester fibre and cellulose diacetate. The dyeing kinetics of polyester were studied as a function of the temperature. The activation energy, the exhaustion and the light and heat fastness were assessed. Only the exhaustion at equilibrium was assessed for cellulose diacetate. The conclusion had been reached that the introduction of such glycoside groups in an azoic chromophoric system did not necessarily affect the dying properties. According to the hydrophilic-lipophilic balance of the final structure it will give rise to disperse dyes that are more suitable for a hydrophobic fibre such as polyester or a more hydrophilic one such as diacetate, but in all cases the toxicity was reduced and the biodegradability of the waste increased. This therefore paves the way for research to define the possibilities and limitations of dyes with glycoside groups. [ABSTRACT FROM AUTHOR]

Melon necrotic spot virus (MNSV) is a water and soil-borne pathogen affecting species of the Cucurbitaceae family both in hydroponic and soil crops. Molecular methods for detecting MNSV in water samples, nutrient solutions and melon plants were developed. For this purpose, water samples from a water source pool of a hydroponic culture or from the recirculating nutrient solution were concentrated by ultracentrifugation or PEG precipitation followed by RT-PCR analysis. Both concentration methods were suitable to allow the detection of MNSV and represent, as far as we know, the first time that this virus has been detected in water samples. A non-isotopic riboprobe specific for MNSV was obtained and used to detect the virus in plant tissue. Different parts of mechanically infected plants were examined including the roots, stems, inoculated cotyledons and young leaves. Excluding the inoculated cotyledons, the tissues showing the highest accumulation levels of the virus were the roots. The potential inclusion of such tools in management programs is discussed. [Copyright &y& Elsevier]

The recent appearance of this fibre has offered the advantages of a manufacturing process that pollutes less than conventional viscose and improves properties of wet tenacity and strength. The behaviour of lyocell fibre in absorption of direct dyes takes on particular importance in the corresponding dyeing stage during the chemical and industrial processing of this fibre. The objective of this study is to characterise the parameters influencing the process of absorption of direct dyes by lyocell fibres by analysing the equilibrium absorption isotherms of C.I. Direct Blue 1 dye. The experimental results were used to define equilibrium equations for interpreting the behaviour of the system through comparative analysis of the equations formulated by Nemst, Freundlich and Langmuir, and the characteristic free internal volume, V(l/kg), for lyocell fibre was calculated. In addition, the characteristic thermodynamic magnitudes of the system were calculated, i.e. the standard enthalpy, entropy and affinity of the dye, to allow satisfactory repetition and prediction of experimental results. Different operating alternatives can thus be compared quantitatively, obtaining the minimum data required for comparative evaluation of the process. [ABSTRACT FROM AUTHOR]

Examines the distribution of B cells in the lymphoid organs of the goat. Utilization of a panel of monoclonal antibodies; Recognition of the greatest number of B cells in the germinative centers; Combined effects of monoclonal antibodies against immunoglobulins.

Focuses on the postnatal development of lymphocyte subpopulations in the intestinal lymph nodes in goats. Role of the intestinal lymph nodes in the absorption and presentation of antigens; Importance of enteric disease in ruminants; Distribution of lymphoid cells.

Three methods were compared for the detection of prunus necrotic ringspot virus in herbaceous and woody plants: DAS-ELISA, nonisotopic dot-blot hybridization and reverse transcriptional polymerase chain reaction (RT-PCR). When purified virus preparations were used, the detection limit of the RT-PCR technique was 1.28 pg mL[sup -1] whereas nonisotopic molecular hybridization and DAS-ELISA allowed detection of 0.8 ng mL[sup -1] and 4 ng mL[sup -1], respectively. Several sample processing procedures were evaluated for virus detection by the nonisotopic molecular hybridization technique. When a very short and simple sample processing method was used, the detection limit of the nonisotopic molecular hybridization technique was 25 times higher than that of DAS-ELISA and 625 times lower than that of RT-PCR. A comparison of the level of virus accumulation in mature fruits and in leaf tissue showed that, on average, 125 times more virus was found in the fruits. [ABSTRACT FROM AUTHOR]