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Most Aristolochiaceae species studied so far are from temperate regions, bearing self-compatible protogynous trap flowers. Although self-incompatibility has been suggested for tropical species, the causes of self-sterility in this family remain unknown. To fill this gap, we studied the pollination of the tropical Aristolochia esperanzae, including the physical and physiological anti-selfing mechanisms. Floral visitors trapped inside flowers were collected to determine the pollinators. Protogyny was characterized by observing the temporal expression of sexual phases and stigmatic receptivity tests. The breeding system was investigated using hand-pollination treatments. Pollen tube growth was observed using epifluorescence to identify the self-incompatibility mechanism. Flies were the most frequent visitors found inside A. esperanzae trap flowers, with individuals from the family Ulidiidae being potential pollinators since they carried pollen. The characteristic flower odour and presence of larvae indicate that A. esperanzae deceives flies through oviposition-site mimicry. Although this species showed incomplete protogyny, stigmatic receptivity decreased during the male phase, avoiding self-pollination. Fruits developed only after cross- and open pollination, indicating that the population is non-autonomous, non-apomictic, and self-sterile. This occurred through a delay in the growth of geitonogamous pollen tubes to the ovary and lower ovule penetration, indicating a late-acting self-incompatibility mechanism. Our findings expand the number of families in which late-acting self-incompatibility has been reported, demonstrating that it is more widespread than previously thought, especially when considering less-studied tropical species among the basal angiosperms.

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Longer stigmas in short-styled morphs of distylous plants have been considered an adaptive characteristic that increases intermorph pollen deposition. The greater pollen deposition in short-styled stigmas may be a by-product of their longer length, making deposition effectiveness comparison between morphs unfeasible. Thus, investigating which morph has the relatively most efficient stigma (i.e., pollen deposition per unit length) can boost our understanding of the adaptive significance of longer stigmas. Here, we compared pollen deposition between morphs relative to stigma length and assessed whether short-styled stigmas are more, less, or equally effective in receiving pollen grains per unit length. We reviewed the literature to characterize the extent of sigma length differences between morphs using the two most speciose distylous genera as model systems: Palicourea and Psychotria (Rubiaceae). Then, we conducted a between-morph comparison of raw and relative pollen depositions in a Palicourea rigida population. We confirmed that short-styled stigmas were longer than long-styled stigmas in both Palicourea (194.31% longer) and Psychotria (52.59% longer) flowers. Furthermore, in the focal Pal. rigida, although short-styled stigmas were 268.04% longer and received 97.04% more pollen grains than long-styled stigmas, the relative pollen deposition had a reverse pattern, with short-styled stigmas being two-times less efficient in receiving pollen. Our results indicate that the longer length of the short-styled stigmas may have a compensatory effect, increasing the chances of pollen grains reaching the stigma and probably maintaining disassortative intermorph pollination in distylous plants.

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Fish processing provides waste of around 50.0% to 70.0% of the animal's initial weight, especially the skin. Thus, this residue contains the by-product that allows biopolymers to be obtained, highlighting collagen, which can be widely used in different areas. The present study aimed to evaluate the yield of collagen extracted from peacock bass Cichla monoculus skin and to characterize them physicochemically. Twenty-five peacock bass with an average weight of 646 ± 175 g were used. The skin samples were removed by manual filleting and weighed, with an average yield of 3.7%. Subsequently, such models were analyzed for chemical composition, showing 61.8% for moisture, 29.3% for crude protein, 1.5% for ash, 6.3% for total lipids, and 1.2% for non-nitrogenous extract (NNE). Acid-soluble collagen (ASC) presented an average yield of 8.2%, presenting in its analysis of centesimal composition 12.5% ​​of moisture, 82.6% of crude protein, 1.1% of ash, 2.6% of total lipids, and 1.2% NNE. The skin and collagen extracted from the tucunaré skin have technological potential for use in the preparation of products, adding value to these by-products from fish processing.

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In many families, plants undergo floral resupination by twisting through approximately 180° during floral development so that the flower is effectively positioned upside down. In most orchids, resupination results in the median petal (i.e., the labellum) becoming lowermost, which plays a crucial role in pollination by serving as a landing platform or as a trapping device, or both. Incomplete resupination is predicted to lead to reduced pollination, although tests of this assumption are still lacking. We investigated the effect of resupination using Phragmipedium vittatum, a rare lady's slipper orchid whose specialized labellum forms a trapping device. First, we surveyed the natural occurrence of incomplete resupination. Then we manipulated flowers into non- (≈0°), half- (≈90°), and fully resupinate (≈180°) positions to test the effect of orientation on pollen smear removal and deposition by pollinators (female hoverflies). We found that ca. 10% of flowers in the natural population were not fully resupinate, being either non- (upward, 0-60°) or half-resupinate (sideward, 60-120°). The change in orientation prevented the effectiveness of pollination by hoverflies since no pollen smear removal or deposition were found in flowers from non- and half-resupinate treatments. Although these flowers still attracted hoverflies, they were not trapped effectively. As this orchid is incapable of autonomous self-pollination, flowers that do not resupinate fail to set fruits. These results highlight the importance of correct floral orientation provided by resupination to ensure pollination in orchids and other resupinate flowers.

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OBJECTIVES: To investigate smoking trajectories and their association with pulmonary function (PF) and respiratory symptoms at age 22. METHODS: Data from a population-based cohort study of 3350 individuals and their spirometries were analysed. The outcomes were: forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), forced expiratory flow at the mid expiratory phase (FEF25-75 %), FEV1/FVC and FEF25-75/FVC ratio. Smoking data were collected at perinatal follow-up (gestational exposure) and 15, 18 and 22 years. Group-based trajectory model was applied. RESULTS: Four groups were identified: no exposure (NE), gestational (GE), gestational and adulthood (GAE) and continuous (CE) exposure. Both CE and GAE trajectories were associated with lower values of FEV1/FVC (-1.77pp; p = 0.01 and -1.58 pp; p<0.001 respectively) and FEF25-75/FVC ratio (-7.27pp; p = 0.019 and -6.04pp; p<0.001 respectively) compared to the NE trajectory. Lower FEV1 and FEF25-75 % values were also related to the GAE trajectory (-68 ml; p = 0.03 and -253 ml/s;p<0.001 respectively). Compared to those who never smoked, individuals who smoked 10 or more cigarettes daily presented a reduction in the FEV1/FVC ratio by 1.37pp (p<0.001), FEF25-75 % by 126 ml (p = 0.012) and FEF25-75 %/FVC ratio by 3.62pp (p = 0.011). CE trajectory showed higher odds of wheezing (OR 4.14; p<0.001) and cough (OR 2.39; p = 0.002) compared to the non-exposed group. CONCLUSIONS: The in-uterus exposure to maternal smoking reduces PF later in life. However, the perpetuation of smoking behaviour throughout adolescence and early adulthood is determinant for PF main reduction and the emergence of respiratory-related symptoms.

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ABSTRACT Diets with high energy density and additives that enhance energy use are necessary for finishing feedlot cattle. The objective of the present study was to evaluate the performance, ingestive behavior, apparent digestibility of the diet and the carcass traits of feedlot steers fed concentrates from different energy sources, one derived from starchy sources and the other, from lipid sources, combined or not with whole soy lecithin, at a dose of 40 g animal day-1. The experimental design was completely randomized blocks, in a 2 x 2 factorial arrangement. The combination of whole soy lecithin with the lipid energy source concentrate increased the dry matter digestibility and the carcass yield of the animals (76.03% and 57.20%, respectively). The lipid energy source concentrate showed higher ether extract digestibility and animals fed on it had higher carcass yield (84.18% and 56.85%, respectively). Whole soy lecithin promoted a reduction in fecal pH due to a greater fermentation of carbohydrates and fatty acids in the intestinal lumen. Using whole soy lecithin combined with energy concentrate from a lipid source is recommended due to its improvements in the use of the diet and in the carcass yield.

RESUMO O uso de dietas com alta densidade energética e aditivos que potencializem o aproveitamento energético se faz necessário na terminação de bovinos em confinamento. O objetivo do presente estudo foi avaliar o desempenho, o comportamento ingestivo, a digestibilidade aparente da dieta e as características de carcaça de novilhos confinados, alimentados com concentrados de diferentes fontes energéticas, um derivado de fontes amiláceas e outro de fontes lipídicas, associados ou não com lecitina integral de soja, na dose de 40g animal dia-1. O delineamento experimental foi o de blocos inteiramente ao acaso, em esquema fatorial 2 x 2. A associação da lecitina integral de soja com o concentrado de fonte energética lipídica melhorou a digestibilidade da matéria seca e o rendimento de carcaça dos animais (76,03% e 57,20%, respectivamente). O concentrado de fonte energética lipídica teve maior digestibilidade do extrato etéreo, e os animais alimentados com este possuíram maior rendimento de carcaça (84,18% e 56,85%, respectivamente). A lecitina integral de soja isolada promoveu redução no pH fecal em virtude de uma maior fermentação de carboidratos e ácidos graxos no lúmen intestinal. Utilizar lecitina integral de soja associada com concentrado energético de fonte lipídica é recomendado devido a suas melhorias no aproveitamento da dieta e no rendimento de carcaça.

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Uncaria tomentosa is a plant native to the Amazon that has immunomodulatory and antitumor properties due to the alkaloids found in the plant, being able to modify the immune response by potentiating or suspending the action of cytokines secreted by macrophages that induce the immune response, either by the classical route (M1) or through the alternative route (M2). Macrophages activated by M1 convert L-arginine into L-citrulline and nitric oxide (NO), whereas macrophages activated by the M2 pathway use the enzymatic activity of arginase to convert the same substrate into L-ornithine and urea. The aim of this work was to evaluate the immunostimulating activity of the crude hydroalcoholic extract from the bark of the U. tomentosa stem in RAW 264.7 macrophages. Concentrations of 0.2, 0.1 and 0.05 mg/mL of U. tomentosa extract associated with LPS, INF-γ and IL-4 inducers were tested by determining NO production and arginase enzyme activity. Nitric oxide production was enhanced by the extract when associated with LPS and LPS + INF-γ inducers. In the activity of the arginase enzyme, the extract decreased the stimulation of IL-4 on the enzyme, mainly at 0.2 mg/mL concentration. Therefore, it is concluded that the crude hydroalcoholic extract of the stem bark of U. tomentosa in RAW 264.7 cells, at a concentration of 0.2 mg/mL, showed considerable pro-inflammatory activity.

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DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

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BACKGROUND: Horizontal atrophic ridges need a regenerative procedure for implant positioning and fixed rehabilitation. Cone Morse taper implants are characterized by the intimate fitting of the prosthetic interface with the absence of microgaps and micromovements of the interfaces. The aim of this case report was to evaluate the clinical outcome of Cone Morse implant design in split crest augmentation treatment. CASE REPORT: A female patient with partial edentulism of atrophic posterior maxilla was treated for split crest procedure and implant-supported rehabilitation. A full-thickness flap was elevated, and horizontal and vertical osteotomic lines were produced with piezoelectric device. A total of 4 Cone Morse Taper implants (Universal III, Implacil de Bortoli, Brasil) were positioned and the site was grafted with bone substitute and covered by a heterologous membrane. CONCLUSIONS: A complete healing of the surgical site was evident at the follow-up with no evidence of bone resorption. No radiolucency or inflammatory aspects of the treated site were evident in the radiographic control. Simultaneous Cone Morse implants positioning with split crest technique seems to be a promising treatment for posterior maxillary rehabilitation of atrophic edentulous ridges.

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Polyploidy and whole genome duplication are major evolutionary drivers in plants. Climate variations during the Pleistocene have influenced distribution and range expansion worldwide. Similar trends have been reported for Cerrado plants, but no attempt has been made to link phylogeography with ploidy and breeding changes. Thus, we aimed to (i) assess ploidy and genome size of Eriotheca estevesiae Carv.-Sobr., and compare it with E. pubescens (Mart.) Schott & Endl. (Both included into the Eriotheca Stellate Trichome Species Complex - ESTSC). (ii) Subsequently, we investigated their phylogeography to see whether genetic structure and range expansion trends were similar to those previously described for the Cerrado biome. Finally (iii), we discuss whether ESTSC phylogeographic patterns could be associated with geographic parthenogenesis processes. Common cytogenetic techniques and flow cytometry were used to confirm chromosome number and genome size of E. estevesiae. We used three cpDNA regions to analyse 14 ESTSC Cerrado populations, for which we also obtained ploidy level and breeding information. We investigated haplotype diversity, population structure and tested neutrality, aiming to reconstruct phylogeographic scenarios. We found three ploidy levels and eight cpDNA haplotypes in ESTSC, one shared by most populations. Haplotype and ploidy distribution corroborated that E. pubescens, the widely distributed polyploid and apomictic species, may have originated from northern diploid and probably sexual E. estevesiae. Matrilinear cpDNA links support the idea that apomixis and polyploidy in ESTSC may have allowed range expansion during the Pleistocene, in a process analogous to the geographic parthenogenesis described elsewhere.

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