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In the last years, microtomography has proved to be a powerful technique on insects' studies, allowing a detailed view of the structures' internal with a high resolution. One of the most important advantages about the use of microtomography in these studies is the fact that the dissection is not necessary, which decreases considerably the number of samples used on the insects' research. Some insects are used constantly in studies about morphology, metamorphosis, and reproduction, because they work as a model for others, and Rhodnius prolixus is one of the most studied in this group. This insect is also one of the main insect vectors of Chagas disease that kills around 12,000 people every year in Latin America. Some studies using laboratory microtomography conventional scanners combining with the correct staining methods have proved that it could be a powerful tool in biological research, allowing the visualisation of low‐density tissues. The main goal of the present work was to use staining protocols to study Rhodnius prolixus with laboratory microtomography conventional scanners. The experiments were carried out at the imaging lab in the Theoretical Biology Department, University of Vienna, using an Xradia MicroXCT and at the University of Oslo, using a Skyscan 2211. LAY DESCRIPTION: Microtomography is a technique widely used to study the inside of insects without the need to cut or dissect them. In this work we used this technique to study an insect called Rhodnius prolixus, well known in Latin America for being the main vector of Chagas disease, which kills around 12,000 people a year. Microtomography can be used in two different ways, through particle accelerators, known as a synchrotron, and also through conventional microtomography. The main objective of this work was to show results of conventional microtomography of Rhodnius prolixus through different staining techniques, to visualize its internal anatomy and thus contribute to future studies of pest control and Chagas disease. The measurements were performed at the University of Vienna and at the University of Oslo [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Background: Rhodnius prolixus is a major vector of Trypanosoma cruzi, the causative agent of Chagas disease in Latin America. In natural habitats, these insects are in contact with a variety of bacteria, fungi, virus and parasites that they acquire from both their environments and the blood of their hosts. Microorganism ingestion may trigger the synthesis of humoral immune factors, including antimicrobial peptides (AMPs). The objective of this study was to compare the expression levels of AMPs (defensins and prolixicin) in the different midgut compartments and the fat body of R. prolixus infected with different T. cruzi strains. The T. cruzi Dm 28c clone (TcI) successfully develops whereas Y strain (TcII) does not complete its life- cycle in R. prolixus. The relative AMP gene expressions were evaluated in the insect midgut and fat body infected on different days with the T. cruzi Dm 28c clone and the Y strain. The influence of the antibacterial activity on the intestinal microbiota was taken into account. Methods: The presence of T. cruzi in the midgut of R. prolixus was analysed by optical microscope. The relative expression of the antimicrobial peptides encoding genes defensin (defA, defB, defC) and prolixicin (prol) was quantified by RT-qPCR. The antimicrobial activity of the AMPs against Staphylococcus aureus, Escherichia coli and Serratia marcescens were evaluated in vitro using turbidimetric tests with haemolymph, anterior and posterior midgut samples. Midgut bacteria were quantified using colony forming unit (CFU) assays and real time quantitative polymerase chain reaction (RT-qPCR). Results: Our results showed that the infection of R. prolixus by the two different T. cruzi strains exhibited different temporal AMP induction profiles in the anterior and posterior midgut. Insects infected with T. cruzi Dm 28c exhibited an increase in defC and prol transcripts and a simultaneous reduction in the midgut cultivable bacteria population, Serratia marcescens and Rhodococcus rhodnii. In contrast, the T. cruzi Y strain neither induced AMP gene expression in the gut nor reduced the number of colony formation units in the anterior midgut. Beside the induction of a local immune response in the midgut after feeding R. prolixus with T. cruzi, a simultaneous systemic response was also detected in the fat body. Conclusions: R. prolixus AMP gene expressions and the cultivable midgut bacterial microbiota were modulated in distinct patterns, which depend on the T. cruzi genotype used for infection. [ABSTRACT FROM AUTHOR]

The majority of the citriculture in Brazil is located in the state of São Paulo, with a total production area of 700,000 ha. Trees are grafted mostly on ‘Rangpur’ lime (RL; Citrus limonia Osbeck) rootstock. Despite its good horticultural performance, use of other rootstocks has increased with the search for disease-tolerant varieties to improve grove productivity and longevity. Furthermore, there is a lack of information on young tree response to fertilization, and optimal nutrient requirements of different scion/rootstock combinations for maximum fruit yield. A network of field experiments was conducted to study the differential response of young sweet orange trees on selected rootstocks to nitrogen (N), phosphorus (P), and potassium (K) fertilization. The application of soil and leaf analyses to develop optimal fertilizer recommendations was evaluated. Experiments were conducted in three locations using fractional factorial design of one-half (4 × 4 × 4) type with four rates of N, P, or K calculated to be applied for five years after tree planting. Fruit yield response was evaluated during the last two years and correlated with soil and leaf analyses data. The trees on RL rootstock demonstrated increased efficiency of nutrient use and fruit production compared with those on ‘Cleopatra’ mandarin (CL; C. reshni hort. ex Tanaka) or ‘Swingle’ citrumelo [SW; Poncirus trifoliata (L.) Raf. × C. × paradisi Macfad.] rootstocks. The trees on SW rootstock appeared to require greater N and K rates than those on RL rootstock. Phosphorus requirement was greater for ‘Natal’ or ‘Valencia’ trees on CL than on RL rootstock. These results will become the basis for revising current fertilizer recommendation guidelines for young trees in Brazil. [ABSTRACT FROM AUTHOR]

Increasingly nitrate nitrogen (NO[SUB3]-N) is found in excess of maximum contaminant limit (MCL) in groundwater adjacent to citrus production areas of central Florida. Understanding of fate of N in the environment following the application of fertilizers is critical to improve nutrient uptake efficiency, minimize nutrient losses and reduce the adverse effects on the groundwater. A study evaluated ammonia volatilization NH[SUB3] and effects of ammonium nitrate (AN) and urea (UR) on N budget of citrus trees on a sandy Entisol. Dry granular N fertilizers were surface applied to irrigated 'Hamlin' orange trees. Ammonia volatilization was evaluated using a semi-open NH[SUB3] trapping system with and without additional air circulation, while net N mineralization and leaching losses were evaluated using in situ incubations with polyvinyl chloride (PVC) columns. Significant N losses by NH[SUB3] volatilization were observed from applied N fertilizers, which accounted for up to 13% of applied N as AN, and 33% as UR with additional air circulation in the collection chamber. These values were significantly greater than those observed with no additional air circulation. Maximum rates of NH[SUB3] volatilization occurred within 5 d after fertilizer application and were greater during the day than during the evening. This study demonstrated that fertilizer use efficiency is reduced due to increased gaseous losses of NH[SUB3] when urea is used, and that N fertilization affects soil N mineralization in a short time period after fertilizer application. Fertilization decreased N mineralization and increased the amount of soil microbial biomass N during incubation. Leaching of N accounted to 13% of applied N during a 90-d period. [ABSTRACT FROM AUTHOR]

Focuses on a study which investigated the possibility of genotype x environment interactions for weaning weight between cattle from different regions in the United States, Canada and Uruguay. Materials and methods; Results and discussion; Implications.

Presents information on a study which estimated genetic and phenotypic variances and covariances for weaning weight in populations of Hereford beef cattle located in the United States, Canada and Uruguay. Similarities of genetic and environmental parameters across the three countries; Methodology of the study; Results and discussion.

Resumo Buscou-se caracterizar a produção científica acerca da experiência da religiosidade/espiritualidade (R/E) em lésbicas, gays e bissexuais (LGBs), via revisão integrativa de literatura nacional e internacional, no período de 2005 a 2015. A busca foi feita nas bases de dados SciELO, PePSIC, LILACS, IndexPsi, PsycINFO, PUBMED e E-journals, sendo identificados e analisados 58 artigos após a consideração dos critérios de inclusão e exclusão. Foram encontrados exclusivamente, estudos internacionais, predominando artigos norte-americanos, empíricos, transversais e qualitativos. As principais categorias de análise qualitativa versam sobre: integração R/E e homossexualidade; R/E como fator de risco e/ou proteção para LGBs; homonegatividade internalizada; e prática clínica. Ressalta-se a contribuição do estudo para a literatura nacional, bem como a relevância da R/E na vivência de LGBs.

Lime application to acid soils usually increases N mineralization but little is known about how it affects the N determined by methods that assess organic N availability. One incubation and three chemical methods were compared in twenty samples of unlimed or limed soils in a pot experiment with maize (Zea mays, L). The N availability methods included the NH4 +‐N released from soils by: a) anaerobic incubation for 7 days at 40°C; b) 2 mol/L KC1 at 100°C for 4 hours and distilled with MgO (hot KCl); c) this same procedure but distilled with 5 mol/L NaOH (hot KCl‐NaOH); and d) 30% v/v H2O2 and MnO2. In addition, inorganic N, total N and organic C were also determined in the soil samples. Readily available inorganic N presented the highest correlation coefficient with N uptake by maize but anaerobic incubation, hot KCl, hot KCl‐NaOH, and total N were also good predictors of soil N availability. The H2O2/MnO2 procedure and organic C produced inconsistent results. The amounts of N extracted by the methods tested were little affected by lime application. Multiple regression analysis showed that, among the methods that assess mineralizable organic N, the hot KCl methods accounted for most of the variation in N uptake by maize. [ABSTRACT FROM PUBLISHER]

Discusses the abstract of the study 'Effect of forage vs. concentrate feeding with or without antioxidants on carcass characteristics, fatty acid composition and quality of Uruguayan beef,' presented at the American Society of Animal Science's Southern Section conference on January 31-February 4, 2003, in Mobile, Alabama.

Thirty Hereford steers were finished either on pasture (n=10) or concentrate (n=20) to determine dietary and antioxidant treatment effects on carcass characteristics, fatty acid composition, and quality of Uruguayan beef. Half of the steers finished on concentrate were supplemented with 1000 I.U. vitamin E head−1 day−1 for 100 days. Postmortem vitamin C was added to ground beef (0.05% v/w) displayed for 8 days at 2 °C. Carcasses from steers finished on concentrate had greater (P<0.05) carcass weight, conformation, degree of finishing, fat depth, and ribeye area than pasture finished animals. Carcasses from pasture-fed steers showed darker (P<0.05) longissimus color and yellower (P<0.05) fat at 24 h postmortem than concentrate-fed. Initial longissimus Warner-Bratzler shear force (WBSF) values were similar (P>0.05) between pasture- and concentrate-fed animals. However, beef from pasture-fed cattle had lower (P<0.05) WBSF values at 7 and 14 days postmortem. Longissimus α-tocopherol concentrations were greater (P<0.01) for pasture- and concentrate-fed animals that were supplemented with vitamin E compared to concentrate-fed. Steaks from pasture-fed and vitamin E supplemented cattle had similar (P>0.05) TBARS values, which were lower (P<0.05) than steaks from concentrate-fed steers during 21 days of display. Ground beef from vitamin E supplemented steers had the lowest TBARS values; whereas samples from pasture-fed animals had the lowest lipid stability with higher TBARS levels than other treatments. Vitamin C addition to ground beef did not (P>0.05) reduce lipid oxidation. Vitamin E supplementation of concentrate-fed cattle had no effect (P>0.05) on color stability of ground beef or steaks. The a&ast; (redness) and b&ast; (yellowness) values were higher (P<0.05) when vitamin C was added to ground beef. Longissimus fatty acid content of concentrate-fed animals was twofold greater (P<0.01) than pasture-fed. The percentages of C14:0, C16:0, and C18:1 fatty acids were higher (P<0.01) in the intramuscular fat of concentrate-fed steers, whereas pasture-fed cattle showed greater (P<0.01) proportions of C18:0, C18:2, C18:3, C20:4, C20:5, and C22:5. Total conjugated linoleic acid (CLA) and CLA isomer c9t11 were higher (P<0.01) for pasture- than concentrate-fed cattle. Vitamin E supplementation of concentrate-fed steers increased lipid stability of ground beef and steaks, but was unable to improve color stability; whereas vitamin C addition to ground beef increased color stability without altering lipid oxidation. Finishing cattle on pasture enhanced the unsaturated fatty acid profile of intramuscular fat in beef including CLA and omega-3 fatty acids. [Copyright &y& Elsevier]

Background: Hemolytic disease of the fetus and newborn is a public health problem caused by maternal-fetal incompatibility; no prophylaxis is available for most alloantibodies that induce this disease. This study reviews the literature regarding which antibodies are the most common in maternal plasma and which were involved in hemolytic disease of the fetus and newborn., Method: Seventy-five studies were included in this review using a systematic search. Two independent authors identified studies of interest from the PubMed and SciELO databases., Main Results: Forty-four case reports were identified, of which 11 babies evolved to death. From 17 prevalence studies, the alloimmunization rate was 0.17 % with 161 babies receiving intrauterine transfusions and 23 receiving transfusions after birth. From 28 studies with alloimmunized pregnant women (7616 women), 455 babies received intrauterine transfusions and 21 received transfusions after birth., Conclusion: Rh, Kell, and MNS were the commonest blood systems involved. The geographical distribution of studies shows that as these figures vary between continents, more studies should be performed in different countries. Investing in early diagnosis is important to manage the risks and complications of hemolytic disease of the fetus and newborn., Competing Interests: Conflicts of interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier España, S.L.U. All rights reserved.)