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Trema, a genus of the popularly known Cannabaceae, has recently been the subject of cannabinoid bioprospection. T. micrantha is a tree with pharmacological potential widely used in folk medicine. It has two types of glandular trichomes, bulbous and filiform, spread throughout the plant body. Considering the proximity of this species to Cannabis sativa and Trema orientalis, species containing cannabinoids, the glandular trichomes of T. micrantha are also expected to be related to the secretion of these compounds. Thus, this study aims to detail the morphology of secretory trichomes during the synthesis, storing and release of metabolites in T. micrantha. We tested the proposition that they could be a putative type of cannabinoid-secreting gland. Pistillate and staminate flowers and leaves were collected and processed for ontogenic, histochemical, and ultrastructural analyses. Both types of glandular trichomes originate from a protodermal cell. They are putative cannabinoid-secreting sites because: (1) terpene-phenols and, more specifically, cannabinoids were detected in situ; (2) their secretory subcellular apparatus is consistent with that found in C. sativa: modified plastids, polyribosomes, an extensive rough endoplasmic reticulum, and a moniliform smooth endoplasmic reticulum. Plastids and smooth endoplasmic reticulum are involved in the synthesis of terpenes, while the rough endoplasmic reticulum acts in the phenolic synthesis. These substances cross the plasma membrane by exocytosis and are released outside the trichome through cuticle pores. The study of the cell biology of the putative cannabinoid glands can promote the advancement of prospecting for natural products in plants. [ABSTRACT FROM AUTHOR]

The combustion of fossil fuels contributes to air pollution (AP), which was linked to about 8.79 million global deaths in 2018, mainly due to respiratory and cardiovascular-related effects. Among these, particulate air pollution (PM2.5) stands out as a major risk factor for heart health, especially during vulnerable phases. Our prior study showed that premature exposure to 1,2-naphthoquinone (1,2-NQ), a chemical found in diesel exhaust particles (DEP), exacerbated asthma in adulthood. Moreover, increased concentration of 1,2-NQ contributed to airway inflammation triggered by PM2.5, employing neurogenic pathways related to the up-regulation of transient receptor potential vanilloid 1 (TRPV1). However, the potential impact of early-life exposure to 1,2-naphthoquinone (1,2-NQ) on atrial fibrillation (AF) has not yet been investigated. This study aims to investigate how inhaling 1,2-NQ in early life affects the autonomic adrenergic system and the role played by TRPV1 in these heart disturbances. C57Bl/6 neonate male mice were exposed to 1,2-NQ (100 nM) or its vehicle at 6, 8, and 10 days of life. Early exposure to 1,2-NQ impairs adrenergic responses in the right atria without markedly affecting cholinergic responses. ECG analysis revealed altered rhythmicity in young mice, suggesting increased sympathetic nervous system activity. Furthermore, 1,2-NQ affected β1-adrenergic receptor agonist-mediated positive chronotropism, which was prevented by metoprolol, a β1 receptor blocker. Capsazepine, a TRPV1 blocker but not a TRPC5 blocker, reversed 1,2-NQ-induced cardiac changes. In conclusion, neonate mice exposure to AP 1,2-NQ results in an elevated risk of developing cardiac adrenergic dysfunction, potentially leading to atrial arrhythmia at a young age. [ABSTRACT FROM AUTHOR]

Studies on seed germination in Eugenia species after embryo fractionation have demonstrated that cotyledon cells have capacity for de-differentiation and consequent production of roots. However, there is no information about the origin of those new roots. Thus, the aim of this study was to characterize anatomically the cotyledon regions of seeds of five species of Eugenia to elucidate the tissue that originates such roots. Seeds were sectioned across the hillum region and immediately placed to germinate. As soon as the fractions of these cut seeds develop roots they were fixed and processed to the usual techniques for light microscopy. The adventitious roots originated only when the seed was fractioned, never occurring spontaneously in uninjured seeds. Adventitious roots were formed from perivascular parenchyma cells, located close to the injured region of the cotyledons. These cells divided periclinally and proliferated, giving rise to a root meristem. Therefore, new seedlings probably have a different genome than the mother plant, but they would be identical to the embryo that was a result of fertilization. [ABSTRACT FROM AUTHOR]

Camoensia scandens is a papilionoid legume inserted in the core genistoid clade. It has large, crepuscular, scented flowers but the corolla is non-papilionaceous, which deviates from the pattern found in the subfamily. The vexillum has a folded claw, forming a tube, which is opposed to the androecium opening; all petals have yellow-gold crinkled margins. In addition, there is a long hypanthium, which stores a translucid liquid. The goal of this study is to elucidate the ontogenetic pathways that result in such a peculiar flower and the glands responsible for the sweet fragrance of the petals. Floral buds and flowers were processed for SEM, TEM and light microscopy analyses. Five sepals arise unidirectionally followed by five petals that initiate simultaneously. After the petals, 11 stamens emerge unidirectionally; a pair of adaxial stamens is opposite to the vexillum. In the intermediate developmental stages the sepals unite basally; the two adaxial sepals unite with each other to a greater extent than with the other sepals. The filaments are basally connate, forming a tube with an adaxial opening at the base. The carpel emerges concomitantly with the two abaxial antepetalous stamens. The long hypanthium forms from the outer floral organs (base of the sepals, petals, filaments) and is attached to the base of the stipe. The corolla is noticeable in the intermediate stages of development. The crinkled golden margins house scent glands formed of a secretory epidermis with secretory trichomes and secretory subepidermal cells. The odor is composed of neutral polysaccharides, nitrogenous substances and essential oils. An extensive nectariferous region is found on the inner surface of the hypanthial tube. The nectar is translucent, viscous and released through large pores. The comparison of our data with that of other genistoid flowers enabled discussions about the pollination and systematics of the group. [ABSTRACT FROM AUTHOR]

The synstigma is a structure formed by clusters of two to several stigmas, whether in the same or between different flowers. Although rare in angiosperms, synstigmas are found in c. 500 out of the c. 750 Ficus spp. (Moraceae). This floral structure is associated with fig-fig wasp pollinating mutualism. The synstigma structure and pollen tube pathways were studied in six Ficus spp. from Ficus section Americanae to test the hypothesis that the synstigma allows pollen grains deposited on a stigma to emit pollen tubes that can grow laterally and fertilize surrounding flowers. Syconia containing recently pollinated stigmas were collected and dissected, and the stigmas were processed for analyses with light and scanning and transmission electron microscopy. The arrangement of the synstigmas across species can be spaced or congested, with the number of stigmas per synstigma ranging from two to 20. Contact between the stigmas in a synstigma occurs by the intertwining of the stigmatic branches and papillae; their union is firm or loose. The pollen tube grows through live cells of the transmitting tissue until reaching the ovule micropyle. Curved pollen tubes growing from one stigma to another were observed in five out of the six species studied. The curvilinear morphology of pollen tubes probably results from competition by pollen between the stigmas composing a synstigma via chemotropic signals. The synstigma appears to be a key adaptation that ensures seed production by flowers not exploited by the fig wasps in actively pollinated Ficus spp. [ABSTRACT FROM AUTHOR]

Parietaria debilis G. Forst. is gynomonoecious, which is a rare condition in the Urticaceae family and among angiosperms. Apetalous flowers of two different morph types (monoclinous, pistillate) occur in the same inflorescence and are reduced in size and in the number of whorls and of organs per whorl. The objective of this study was to compare the morphogenesis of monoclinous and pistillate flowers to determine whether the monoclinous flowers produce fertile gametophytes, and elucidate the pathways leading to the absence of stamens and to the changes in number of whorls and organs per whorl. Flower buds and flowers (non-fertilized, fertilized) were processed for surface and anatomical studies. Pollen ultrastructure and viability were determined. Inflorescences with fertilized flowers were checked for the presence and location of fruits/viable seeds. The monoclinous flower has four sepals, four stamens, and a uniovulate pseudomonomerous gynoecium. In the pistillate flower, the stamens are absent or, rarely, aborted. No petals are formed. The gynoecium is pseudomonomerous, originated as a central primordium that differentiates into two carpels, but only one develops and houses an ovule. Monoclinous and pistillate flowers produce viable seeds. Thus, our data confirmed that this species is indeed gynomonoecious. [ABSTRACT FROM AUTHOR]

The present chapter deals with the concept as well as the structure, ultrastructure and development of laticifer in plants. The morphological aspects of the laticifer development are used to better support the laticifer current classification. Some general functions attributed to the laticifer are discussed, especially those related to the plant protection. As a novelty we cited a role of laticifer presence and distribution in the pollination of the fig trees. An extensive bibliographic survey on taxonomic distribution of laticifers in plants is presented. Illustrations of anatomy, histochemistry and ultrastructure of laticifers are presented to exemplify the treated aspects. Unpublished or recently published aspects are highlighted in each topic. We showed that there is a great diversity of morphological types of laticifers and developmental processes involving the laticifer formation in plants. [ABSTRACT FROM AUTHOR]

The presence of articulated laticifers in the Moraceae family was recently discovered, which means that the location of pectinase and cellulase activities must be of great importance for their growth. Thus, the present study aimed to determine the role of these enzymes in the laticifer growth in Ficus montana and Maclura tinctoria. Reproductive meristems were collected and fixed in Karnovsky. Pectinase and cellulase labeling was performed in part of the samples, while another part was processed for usual TEM analyses. Pectinase and cellulase activities were detected in the vacuole and close to the middle lamella in both species. The presence of cellulases in the laticifers supports their articulated origin. Therefore, the occurrence of pectinase and cellulase activity in the laticifers points out that these enzymes could act in the dissolution of the transverse walls and in the processes of intrusive growth (through the dissolution of the middle lamella) and cell elongation (through the partial disassembly of components of the wall making it more plastic). Both enzymes are synthesized in the endoplasmic reticulum and transported to the cell wall by exocytosis or stored in the vacuole. The species studied showed a diverse subcellular composition, which is probably related to the species and not to the laticifer type (they present the same type) and to the composition of the latex (they show similar latex composition). We conclude that the presence of pectinases and cellulases can be used as a diagnostic condition for the laticifer types (articulated vs. non-articulated). [ABSTRACT FROM AUTHOR]

In this study, we reassessed the morphology and distribution of laticifers present in the inflorescences of nine Moraceae and three Urticaceae species and compared the substances found in their latices. Reproductive meristems and inflorescences at different developmental stages were collected, fixed and processed for light microscopy analysis. In Moraceae, laticifers occur in almost all inflorescence organs. In Urticaceae, the presence of laticifers in the inflorescence axis and sepals is a novelty, since the family is characterized by having laticifers only in the bark. The laticifers of Moraceae and Urticaceae show a thin pectocellulosic cell wall and are articulated and branched, although they are currently classified as non-articulated branched in Moraceae and non-articulated unbranched in Urticaceae. The latex contains proteins and alkaloids. Lipids are common in Moraceae latex, whereas phenolic compounds occur in the Urticaceae latex. Polysaccharides occur in the majority of the species studied, an unprecedented finding for the group. Thus, we found that the non-articulated type of laticifer may not consist of a synapomorphy for Moraceae and Urticaceae. Moreover, the laticifer branching in the inflorescences of Urticaceae indicates that its distribution and ramification as acknowledged in the literature (restricted to the bark and unbranched) should be reevaluated and may not constitute synapomorphies for this family either. The adaptive value of laticifers for Moraceae and Urticaceae is high, since they occur widely in the plant body of their representatives. The presence of proteins and alkaloids in the latex and the absence of starch grains are probably conserved traits in the urticinean rosids. [ABSTRACT FROM AUTHOR]

Locomotor behavioral sensitization represents an animal model for understanding neuroadaptive processes related to repeated drug exposure. Repeated stress can elicit a cross-sensitization to the stimulant response of ethanol, which involves neuronal nitric oxide synthase (nNOS). Activation of N-methyl d -aspartate (NMDA) glutamate receptors triggers nNOS and the synthesis of nitric oxide (NO). In this study, we investigated the effects of blocking NMDA receptors using the NMDA receptor antagonist MK-801 on the cross-sensitization between restraint stress and ethanol. We also evaluated the nNOS activity in the prefrontal cortex (PFC) and hippocampus. Mice were pretreated with saline or MK-801 30 min before an injection of saline or stress exposure for 14 days. On the following day, they were challenged with either saline or 1.8 g/kg ethanol. Swiss male mice pretreated with 0.25 mg/kg MK-801 exhibited a sensitized response to ethanol. Moreover, MK-801 potentiated the cross-sensitization between stress and ethanol. However, MK-801 prevented the enhanced nNOS activity in stress-exposed groups (challenged with saline or ethanol) in the PFC; the antagonist also prevented the ethanol-induced increase in nNOS activity and reduced this enzyme activity in mice exposed to stress in the hippocampus. These data indicate that systemic treatment with the NMDA antagonist potentiated, rather than blocked, ethanol-induced behavioral sensitization and that this effect is dissociable from the capacity of NMDA antagonists to reduce ethanol/stress-induced NOS stimulation in the PFC and hippocampus. • Repeated MK-801 elicits a sensitized response to acute ethanol. • MK-801 potentiates cross-sensitization between stress and ethanol. • Acute ethanol increases nNOS activity in the PFC and hippocampus. • Ethanol-induced nNOS activation in the hippocampus is prevented by MK-801. • NNOS activity in mice exposed to stress is mitigated by MK-801. [ABSTRACT FROM AUTHOR]

The stigma plays several roles such as pollen hydration and selection, and pollen tube nutrition. In the Ficus -fig wasp mutualism, stigmata have an additional, almost unknown, function by representing a physical interface for both plant and wasp reproduction. We used light and electron microscopy to compare the detailed morphology of the stigmata of nine Ficus species of different sections and with different pollination modes and sexual expressions. Figs were collected at the stage when the stigmata were receptive for pollination. Stigmata in actively pollinated monoecious species have well developed papillae concentrated on the adaxial surface exposed towards the fig cavity. Conversely, the passively pollinated monoecious species have the whole surface of the stigmata covered by somewhat smaller papillae. In both actively and passively pollinated monoecious species these features are consistent, irrespective of style length. In all actively pollinated gynodioecious species, the stigmata of pistillate flowers were tubular or infundibuliform whereas in almost all actively pollinated monoecious species (except F. racemosa ) the stigmata were filiform, with one branch or two asymmetric branches. In gynodioecious species the short-styled flowers in “male” figs show a limited receptive surface with small papillae, while the stigmata of long-styled flowers in “female” figs are covered by papillae that extend down the sides of the style, increasing the stigmatic surface. In actively pollinated species, stigmata are cohesive, forming a common surface for pollen tube germination (= synstigma). The synstigma arrangement was quite variable: lax, cohesive or very cohesive, with entanglement by stigmatic papillae and stylar trichomes. Entanglement by stylar trichomes is common in gynodioecious species. The synstigma arrangement did not correlate with phylogeny or breeding system. This study is the first to report a very loose synstigma in actively pollinated monoecious Ficus species. Our analyses revealed that, in Ficus , the synstigma is functionally analogous to an extra-gynoecial compitum. Comparative studies will be required to test further hypotheses about the evolutionary determinants of such variation. [ABSTRACT FROM AUTHOR]

Introduction and aim: The nutrition labelling of foods is important for the population because with it is easy to know the nutritional properties of each food, thereby contributing to an appropriate food consumption. In this order, the study proposed check the line of the amount of nutrients present in processed foods intended for children, focusing on the age group of 4 to 8 years of age, with the amount of nutrients recommended by the Dietary Reference Intakes. Materials and methods: Were collected data on the nutritional charts of 18 products, considering the average of three different brands for each item, as availability in a supermarket in the town of Pinhão-PR. Results: Presented products with high adequacy percentage in relation to the recommendations, and of eighteen foods evaluated, the instant noodles, the breaded chicken and the Burger stood out with greater amount of calorific value, of saturated fats, total fat and sodium. With respect to trans fats, food 14 claim not present significant amount in portion. Conclusion: Whereas the consumption of processed foods by children, it is important to perform actions to raise awareness among adults and children about the nutritional labels, to clarify the meanings of information and promote access to a higher quality power supply. [ABSTRACT FROM AUTHOR]

Premise of research. This study compares the development of staminate and hermaphrodite flowers of Parkia multijuga and Stryphnodendron adstringens, two andromonoecious mimosoid trees, in order to determine whether diclinous flowers result from the same developmental processes. The issues involving the interesting structure of the perianth were also addressed. Methodology. Flowers and flower buds of various sizes were processed for surface and histological observations. Pivotal results. Five sepal primordia emerge in the floral meristem from the abaxial side in a sequential order in P. multijuga and from the adaxial side of the flower in a modified helical order in S. adstringens. Five petal primordia initiated simultaneously in P. multijuga and S. adstringens. The carpel primordium initiates concomitantly with five antesepalous stamen primordia in P. multijuga and after petal elongation in S. adstringens. All connections among floral organs in P. multijuga (gamosepaly, gamopetaly, epipetaly, and staminal tube) and S. adstringens (gamosepaly and gamopetaly) are postgenital. A sixth sepal primordium found in some S. adstringens flowers is formed late in the development. Early ontogenetic stages are similar between hermaphrodite and staminate flowers of both species, and only in middevelopmental stages does the carpel primordium stop elongating; no ovule, style, or stigma is formed, leaving only a small carpellodium in the center of the staminate flowers. Conclusions. Our ontogenetic studies show that carpel abortion, not carpel absence from inception, results in staminate flowers in two andromonoecious legumes. [ABSTRACT FROM AUTHOR]

Premise of research. Anther glands display great morphological diversity and features with potential ecological and taxonomic value in the Mimosoideae group. The current knowledge about these glands is mainly based on external morphological observations, lacking data on the anatomy of the glands. A detailed anatomical study of the glands is a crucial step toward a more comprehensive understanding about these structures because it provides valuable information for further studies about their ontogeny, functions, and homology. Therefore, the goal of this study was to revisit anther gland anatomy in Mimosoideae species to provide a more detailed characterization. Methodology. We investigated anther glands from 25 species of Mimosoideae placed in different clades. Buds immediately preceding anthesis were collected and fixed in neutral buffered formalin solution. Anthers were removed and processed for surface and anatomical analyses. Pivotal results. We found four main types of anther glands in Mimosoideae. The general Piptadenia type is characterized by a stalked gland with rounded apex and includes three subtypes: Piptadenia, characterized by a gland composed of isodiametric cells; Adenanthera, a gland composed of one epidermal layer and isodiametric central cells; and Entada, composed of one epidermal layer that delimits a lumen. The Pentaclethra type is a robust gland composed of a palisade epidermal layer and isodiametric central cells, with vascularized stalk; the Prosopis africana type is a robust sessile and vascularized gland; and, finally, the Gagnebina type is an acuminate gland with elongated cells. Conclusions. The diversity of anther gland morphology lies in both external and anatomical features. Piptadenia subtype Piptadenia occurs in most of the studied species and likely is the common type for Mimosoideae. Glands with anatomical similarity occur in closely related groups, suggesting that the type of anther gland is a character with potential phylogenetic significance. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is particularly produced in the skin, where it participates in the regulation of inflammation, pruritus, cytoprotection, scarring, and angiogenesis. In this study, we compared the effects of dexamethasone (Dex) with two H2S-releasing Dex derivatives in a murine model of atopic dermatitis (AD) induced by topical application of 2,4-dinitrochlorobenzene (DNCB). After sensitization with DNCB, the animals were topically treated for five consecutive days with either the H2S-releasing compounds 4-hydroxy-thiobenzamide (TBZ) and 5-(p-hydroxyphenyl)-1,2-dithione-3-thione (ADT-OH), Dex, or the derivatives Dex-TBZ or Dex-ADT. Topical treatment with equimolar doses of either Dex, Dex-TBZ, or Dex-ADT resulted in similar reductions in dermatitis score, scratching behavior, edema, eosinophilia, splenomegaly, and histological changes. In contrast with Dex, the H2S-releasing derivatives prevented IL-4 elevation and oxidative modification of skin proteins. On an equimolar dose basis, Dex-TBZ, but not Dex-ADT, promoted the elevation of endogenous H2S production and GPx activity. Neither Dex-TBZ nor Dex-ADT decreased GR activity or caused hyperglycemia, as observed with Dex treatment. We conclude that the presence of H2S-releasing moieties in the Dex structure does not interfere with the anti-inflammatory effects of this corticosteroid and adds beneficial therapeutical actions to the parent compound. [ABSTRACT FROM AUTHOR]

Premise of research. We present a detailed analysis of the floral ontogeny ofAmburana cearensis, which is an early-branching papilionoid legume with an unusual floral morphology. Especially the reduced one-petalled corolla is noteworthy and stimulates the question about the ontogenetic background of this reduction. Are all five petals initiated and later reduced, or are four petals completely lost (i.e., without any primordia evident)? Ontogenetic studies of early-branching papilionoids provide important insights for the understanding of relationships down to caesalpinioid legumes and up to derived papilionoid lineages. Methodology. We analyzed inflorescences, flowers, and flower buds with the SEM using standard procedures. Pivotal results. Sepals and petals are initiated bidirectionally, which is a rare character among papilionoid legumes. The reduced one-petalled corolla is the result of early suppression of four petal primordia. Stamen formation is in reversed unidirectional order starting from the adaxial side of the flower. This is a rare character among Leguminosae. Floral characters that could be important for floral ecology are the rapid growth of the adaxial petal, which participates in bud protection; a long hypanthium with nectariferous stomata in the lower half; two fenestrae at the left and right of the adaxial stamen, through which nectar is accessible; and reduced anthers in the inner stamen whorl (i.e., heteranthery), which might be related to the reduction of four petals. Conclusions. Our study highlights the importance of ontogenetic studies among the diverse early-branching papilionoid lineages. Floral ontogeny in Amburana deviates considerably from the unidirectional pathway that is a common pattern among more derived papilionoid lineages. Organ reduction is based on the abortion of initiated primordia. Our study contributes to a better understanding of early-branching papilionoids and their systematic relationships. [ABSTRACT FROM AUTHOR]

Mitochondria-targeted hydrogen sulfide (H2S) donor compounds, such as compound AP39, supply H2S into the mitochondrial environment and have shown several beneficial in vitro and in vivo effects in cardiovascular conditions such as diabetes and hypertension. However, the study of their direct vascular effects has not been addressed to date. Thus, the objective of the present study was to analyze the effects and describe the mechanisms of action of AP39 on the in vitro vascular reactivity of mouse mesenteric artery. Protein and gene expressions of the H2S-producing enzymes (CBS, CSE, and 3MPST) were respectively analyzed by Western blot and qualitative RT-PCR, as well the in vitro production of H2S by mesenteric artery homogenates. Gene expression of CSE and 3MPST in the vessels has been evidenced by RT-PCR experiments, whereas the protein expression of all the three enzymes was demonstrated by Western blotting experiments. Nonselective inhibition of H2S-producing enzymes by AOAA abolished H2S production, whereas it was partially inhibited by PAG (a CSE selective inhibitor). Vasorelaxation promoted by AP39 and its H2S-releasing moiety (ADT-OH) were significantly reduced after endothelium removal, specifically dependent on NO-cGMP signaling and SKCa channel opening. Endogenous H2S seems to participate in the mechanism of action of AP39, and glibenclamide-induced KATP blockade did not affect the vasorelaxant response. Considering the results of the present study and the previously demonstrated antioxidant and bioenergetic effects of AP39, we conclude that mitochondria-targeted H2S donors may offer a new promising perspective in cardiovascular disease therapeutics. [ABSTRACT FROM AUTHOR]

Two legume trees largely known as tannin producers--Dimorphandra mollis Benth. (Caesalpinioideae) and Stryphnodendron adstringens (Mart.) Coville (Mimosoideae)--were used asmodels to elucidate themorphology and ontogeny of tannin cells. Vegetative parts of plantswere processed for observation using light and electronmicroscopy (scanning and transmission). Idioblasts, found even in young plants of both species, and secretory trichomes, observed in vegetative buds of mature plants of S. adstringens, are respon- sible for tannin production. The tanniniferous idioblasts originate from protoderm and also from ground meristem cells. The ground meristem proved to be the best place to study the development of tanniniferous idioblasts at different stages of development, which allowed us to monitor the production and accumulation of tannins in the same tissue. Our data indicate that there is a relationship between the production of tannins and the process of vacuolation of tanniniferous cells. The results also indicate the probable performance of rough endoplasmic reticulum (RER) and plastids in the production of tannins. [ABSTRACT FROM AUTHOR]

In this study, we recorded, for the first time, the occurrence of leaf glands in a member of Styracaceae and their association with bacteria. Samples of Styrax camporum Pohl shoot apices and leaves at different developmental stages were prepared according to the conventional techniques for light and electron microscopy. Glands are emergences constituted by epidermal and parenchyma cells and are differentiated into a secretory body on a short nonsecretory stalk supplied with phloem. Actively secreting glands occur from leaf primordia to mature leaves and produce mucilage that accumulates inside schizogenous intercellular spaces. The epidermal secretory cells have abundant cytoplasm rich in hyperactive dictyosomes, an extensive endoplasmic reticulum, and modified plastids. Bacteria enter the gland via the intact surface and proliferate in the intercellular spaces of the glands. Once inside the intercellular spaces of the glands, bacteria enter the cells owing to the weakening of the anticlinal and inner periclinal cell walls and by phagocytosis. Strands of actin filaments occur near the endocytical vesicles containing degenerating bacteria. Accumulations of phenolic compounds and callose could explain the absence of bacteria in the stalk cells. The presence of bacteria inside the leaf glands of S. camporum is a regular and cyclic trait. The significance of the bacteria (not yet identified) and the type of interaction between these two organisms remain unknown. [ABSTRACT FROM AUTHOR]

Abstract: The receptacles of fig trees (Ficus spp.) can harbor a highly diversified and complex community of chalcid wasps. Functional groups of fig wasps (e.g. gallers, cleptoparasites and parasitoids) oviposit into the fig at different developmental stages, reflecting different feeding regimes for these insect larvae. There are few direct data available on larval feeding regimes and access to resources. We studied the gall induction and larval feeding strategy of an Idarnes (group flavicollis) species, a non-pollinating fig wasp (NPFW) associated to Ficus citrifolia P. Miller in Brazil. This Idarnes species shares with the pollinator characteristics such as time of oviposition, ovipositor insertion through flower and location of the egg inside plant ovaries. Nevertheless, we show that the gall induction differs considerably from that of the pollinating species. This Idarnes species relies on the induction of nucellus cell proliferation for gall formation and as the main larval resource. This strategy enables it to develop in both pollinated and unpollinated figs. The large differences between this NPFW and other fig wasps in how ovules are galled suggest that there are different ways to be a galler. A functional analysis of NPFW community structure may require descriptions of the histological processes associated with larval development. [Copyright &y& Elsevier]

Abstract: Calliandra brevipes Benth. is an American shrubby species largely used for ornamental purposes. Like all other Calliandra species it has heteromorphic pollen grains shed in ellipse-shaped, calymmate polyads and a unique mode of pollen presentation by producing a sticky substance called “pollen adhesive”. The present study aimed to investigate in detail the origin of polyad adhesive in C. brevipes. Serial microtome sections of anthers in various developmental stages were used and histochemical tests applied to detect the adhesive production sites and investigate the subcellular characteristics of the anther cells under transmission electron microscopy. The pollen adhesive in C. brevipes is not only produced by parenchymatic cells of the anther transversal septum, as it is described for Calliandra angustifolia, but parenchymatic cells and tapetal cells next to the polyad apical pollen grain also participate in the pollen adhesive production. The cytoplasm of the degenerating tapetum cells contains oleoplasts and fibrogranular material inside the vacuoles which mixes with the adhesive produced by adjacent parenchymatic cells and which therefore contributes to its composition. Vacuoles containing fibrogranular material are very similar to those found in tryphine producing tapetal cells, and the subcellular structures of parenchymatic and tapetal cells are similar to each other. The fact that the pollen adhesive becomes solid in contact with the environment is attributed to dehydration and the presence of the protein fibrogranular material and lipid substances since resin could not be found in its composition. It seems that the sites of pollen adhesive production in Calliandra may vary among its members. Studies of polyad adhesive production in the genus should be standardized in order to verify the information already available in the literature. [Copyright &y& Elsevier]

Abstract: Inga vera, native to South America, is an important leguminous species used for ecological restoration of riparian forests and its seeds are among the most recalcitrant ones described up to date. In this work, we analysed the metabolic profile, cell ultrastructure as well as cell wall polysaccharides of I. vera seeds in order to better understand its maturation, which allows embryo germination without a quiescent phase. Increased amounts of citric, glutamic, pyroglutamic, and aspartic acids from stages I to II (120 and 129 days after flowering (DAF)) corroborate the hypothesis of high metabolism, shifting from fermentative to aerobic respiration at seed maturity. This phase was characterized by an extensive vacuolization of embryonic cells, which also indicate high metabolic activity. The proportion of arabinose in the cell walls of embryonic axis (approx. 20%) was lower than those found in some orthodox seeds (nearly 40%), suggesting that arabinose-containing polysaccharides, which are thought to provide more flexibility to the cell wall during natural drying, are less abundant in I. vera seeds. Taken together, our results provide evidence that the major changes occurred during early stages of seed maturation of I. vera, indicating that the rapid temporary metabolic shift observed between stages I and II may be related to the lack of desiccation phase, moving directly to germination. [Copyright &y& Elsevier]

The genus Miconia, Melastomataceae, has been highlighted for its high proportion of apomictic species, in which the occurrence of low pollen grain viability is commonly recorded. In this study, we compared aspects of pollen development and viability and ploidy level in a sexual species, Miconia pepericarpa, and an apomictic species, Miconia fallax, and investigated the possible causes of pollen grain sterility in apomictic species. Abnormal meiosis was observed only in apomictic M. fallax and leads to the formation of inviable pollen grains, often with little or no cytoplasmic content. Furthermore, the apomictic species is polyploid, and therefore, chromosomal imbalance would be expected. Symmetric mitotic division was found only inM. fallax, also resulting in inviable pollen grains, usually with cytoplasm content but without generative cell differentiation. At the end of development, the apomictic species also displays another difference when compared with the sexual species: the generative cell does not become fusiform but, rather, maintains a spherical shape. It is unknown whether the generative cell shape may interfere with its function. [ABSTRACT FROM AUTHOR]

The syconium is the urn-shaped inflorescence shared by all species of the genus Ficus. The orifice at the apex of the syconium is called the ostiole, and it is covered by interlocking bracts. The ostiolar bracts can have different arrangements, which only allow the entry of mutualist wasps and promote reproductive isolation among Ficus species. Here, we analyze the ostiolar structures that could play a role as selective filter and therefore impact the fig-fig wasp mutualism in the neotropical Ficus sections Americanae and Pharmacosycea. Samples of syconia with pistillate flowers during the receptive phase of seven species of Ficus were examined using light and scanning electron microscopy. Tests for histolocalization of substances were employed to detect secretory activity throughout the ostiolar tissues. Our results indicated that the ostiole has two components: ostiolar bracts and the periostiolar zone. Interspecies variation in ostiolar bract arrangement in both sections studied was broader than previously reported. We report for the first time for Ficus: (i) two types of ostiolar osmophores (mesophyll and diffuse), that could be a source of volatile compounds for attracting fig wasps; (ii) colleters in the axil of ostiolar bracts, which probably lubricate and facilitate the entry of pollinating wasps into the syconial cavity; (iii) secretory trichomes around the ostiolar bracts, and (iv) syconium basal bracts (F. isophlebia) covering the ostiole, which are the first physical barrier that the fig wasps must overcome to access receptive pistillate flowers. We describe the zones that compose the ostiole, which support the hypothesis that the ostiole is a selective filter in the interactions of fig trees with Agaonidae fig wasps. We also suggest that ostiolar osmophores, colleters, the periostiolar zone, and the arrangements of the ostiolar bracts may be informative with respect to Ficus systematics. [ABSTRACT FROM AUTHOR]

Mutualisms such as the fig-fig wasp mutualism are generally exploited by parasites. We demonstrate that amongst nonpollinating fig wasps (NPFWs) parasitic on Ficus citrifolia, a species of Idarnes galls flowers and another species feeds on galls induced by other wasps killing their larvae. The galling wasp inserts its ovipositor through the fig wall into the fig cavity. The ovipositor then follows a sinuous path and is introduced through the stigma and style of the flower. The egg is deposited between the integument and nucellus, in the exact location where the pollinating mutualistic wasp would have laid its egg. Gall induction is a complex process. In contrast, the path followed by the ovipositor of the other species is straightforward: attacking a larva within a developed gall poses different constraints. Shifts in feeding regime have occurred repeatedly in NPFWs. Monitoring traits associated with such repeated evolutionary shifts may help understand underlying functional constraints. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106, 114-122. [ABSTRACT FROM AUTHOR]

Abstract: The ecological and economic importance of oleoresin produced by Copaifera langsdorffii is well established. This study aims to investigate the ontogeny, anatomy and ultrastructure of the internal glands of C. langsdorffii during plant development. Samples were processed for light and electron microscopy and a specific technique was applied to impregnate endomembranes. Internal secretory glands were observed in the hypocotyl, epicotyl and eophylls of seedlings, and in the primary stem, pulvinus, petiole, rachis and leaf blade of adult plants. Canals and cavities show differential distribution. They arise from ground meristem cells, and the lumen is first formed by schizogenesis followed by later schizolysigenous development. The dense cytoplasm of epithelial cells shows mitochondria, plastids without thylakoids, polyribosomes and endoplasmic reticulum. A periplastidial reticulum was also observed. Secretion is released by eccrine, granulocrine and holocrine processes. Lipophilic and hydrophilic compounds were histochemically detected in both canals and cavities, whereas resin was detected only in canals. The presence of these substances has been associated with plants’ defences against dehydration, as well as against attacks from herbivores and pathogens, from seedling stage onwards. [Copyright &y& Elsevier]

Abstract: Research documents related to the morphology and function of style branches and stigmatic surface of Asteraceae are still rather few, and the literature reports are thus controversial. We report in the present study that the stigmatic surfaces of two non-related species of Asteraceae (Lessingianthus grandiflorus and Lucilia lycopodioides) have features of semidry stigmas. Sporodermis of both species was also analyzed so that we could understand how the stigmatic surface works during pollen deposition and rehydration. Stylar branches and pollen grains (sporodermis) were studied using scanning and transmission electron microscopy (SEM and TEM) and histochemistry techniques. The inner and marginal bands of stylar branches in these species display intermediary features between the dry and wet types of stigma: the cuticle characterizes the dry stigma and cells with secretory activity characterize the wet stigma; these showed differences from what has been described to the Asteraceae family, where stigmatic surface of species from several tribes is considered dry. Pollen grains are medium-size to large with exine ornamentation (echinate and echinolophate) and abundant secretion which latter characterizes pollenkitt. We can assume that two processes might help pollen grain hydration on stigmatic surface in Lessingianthus grandiflorus and Lucilia lycopodioides: (1) the presence of pollenkitt, as observed in the secretory content inside exine cavities and around pollen grains; and (2) the secretory activity of stigmatic surface cells, whose secretion accumulates among intercellular and subcuticular spaces and leads to cuticle disruption during the floral receptive phase. Our results suggest that ultrastructural and histochemical studies should be considered when describing stigmatic surface and that the “semidry” feature within Asteraceae should be investigated still more in detail, so that the taxonomic or adaptation value of this trait in the family can be verified. [Copyright &y& Elsevier]

Abstract: Inflorescence and floral development of two tropical legume trees, Dahlstedtia pinnata and Dahlstedtia pentaphylla, occurring in the Atlantic Forest of south-eastern and southern Brazil, were investigated and compared with other papilionoids. Few studies have been made of floral development in tribe Millettieae, and this paper is intended to fill that gap in our knowledge. Dahlstedtia species have an unusual inflorescence type among legumes, the pseudoraceme, which comprises axillary units of three or more flowers, each with a subtending bract. Each flower exhibits a pair of opposite bracteoles. The order of flower initiation is acropetal; inception of the floral organs is as follows: sepals (5), petals (5), carpel (1) plus outer stamens (5) and finally inner stamens (5). Organ initiation in sepal, petal and inner stamen whorls is unidirectional; the carpel cleft is adaxial. The vexillum originates from a tubular-shaped primordium in mid-development and is larger than other petals at maturity, covering the keels. The filament tube develops later after initiation of inner-stamen primordia. Floral development in Dahlstedtia is almost always similar to other papilionoids, especially species of Phaseoleae and Sophoreae. But one important difference is the precocious ovule initiation (open carpel with ovules) in Dahlstedtia, the third citation of this phenomenon for papilionoids. No suppression, organ loss or anomalies occur in the order of primordia initiation or structure. Infra-generic differences in the first stages of ontogeny are rare; however, different species of Dahlstedtia are distinguished by the differing distribution pattern of secretory cavities in the flower. [Copyright &y& Elsevier]

Abstract: Interactions of leukocytes with endothelium play a role for the immune system modulated by endogenous agents, such as glucocorticoids and nitric oxide (NO). Glucocorticoids inhibit leukocyte-endothelial interactions whereas the role of NO is still controversial. In this study, the activity of Ca+2-dependent nitric oxide synthases was in vivo blocked in male Wistar rats by given l-NAME, 20mgkg−1 for 14 days dissolved in drinking water and expression of adhesion molecules involved in leukocyte-endothelial interactions was investigated. Expressions of L-selectin and PECAM-1 in peripheral leukocytes and PECAM-1 in endothelial cells were reduced by l-NAME treatment. Only L-selectin expression was controlled at transcriptional levels. These effects were not dependent on endogenous glucocorticoids, as corticosterone levels were not altered in l-NAME-treated rats. Our results show that NO, produced at physiological levels, controls expression of constitutive adhesion molecules expressions in cell membranes by different mechanisms of action. [Copyright &y& Elsevier]

• Tropical plant reproductive processes are vulnerable to climate change. • Warming and eCO 2 induced early degeneration of tapetum cells of pollen sacs. • Warming and eCO 2 induced a less differentiated aperture of pollen and compaction of pollen exine. • Warming and eCO 2 induced abnormalities which may hinder the viability of pollen grain. Global climate change is expected to have impacts on the physiological, phenological, and morphological traits of plants. However, the vulnerability of tropical plant reproductive processes in response to climate change events has been poorly studied. Here, we assess if warming and elevated CO 2 compromise the pollen characteristics of Stylosanthes capitata Vogel, a tropical legume forage species. This work was conducted in a Trop-T-FACE (combined Free-Air Temperature Controlled Enhancement and Free-Air Carbon Dioxide Enrichment) facility, where we exposed the plants to four treatments: C (Control -ambient atmospheric carbon dioxide concentration [CO 2 ] and ambient temperature); eCO 2 (increase in [CO 2 ] to 600 ppm and ambient temperature); eT (canopy temperature increase by 2°C and ambient [CO 2 ]); and eCO 2 + eT, a combination of both treatments. We analyzed pollen morphology of samples taken from the different treatments through light microscopy (LM) and scanning electron microscopy (SEM). In addition, pollen viability was analyzed through colorimetry. Based on the histological LM analysis, the tapetum cells of pollen sacs showed early degeneration under eT (72%) added to hypertrophy under eCO 2 (67%) and eCO 2 + eT (90%) treatments. SEM images showed compaction of pollen exine and less distinguishable pollen apertures in the treated plots (eCO 2 , eT , and eCO 2 + eT), possibly, by the early death of the tapetum cells. These morphological abnormalities may hinder the viability of pollen grains, as observed especially in the eCO 2 + eT treatment (%V=64%) that was the lowest in comparison with the Control (71%) and the other treatments (eCO 2 = 69%, eT = 67%). These results indicate that during the reproductive cycle of S. capitata pollen sacs and pollen grains are vulnerable to warming, elevated CO 2 , and their combined effects. [ABSTRACT FROM AUTHOR]

Flower and inflorescence anatomy and morphology of Exostyles, Harleyodendron, Holocalyx, Lecointea, and Zollernia (Leguminosae, Lecointea clade) were studied. Features common to all genera but otherwise rare within the Leguminosae include: (1) the presence of phenolic compounds in the epidermal cells of the anthers and subepidermal cells of the bracteoles, sepals, petals, and ovaries (absent in Holocalyx balansae); (2) simple trichomes on the adaxial base of the bracteoles and on the surface of the calyx and ovaries; and (3) tapetum persisting until the androspores are formed. Other notable anatomical features are: (1) colleters on the adaxial bases of the bracts and bracteoles of Holocalyx balansae and Zollernia ilicifolia; (2) trichomes on the anthers of Harleyodendron unifoliolatum, Holocalyx balansae, Lecointea hatschbachii, Zollernia ilicifolia and Z. magnifica; (3) osmophores on the petals of Exostyles godoyensis; (4) asynchronous pollen development in the anthers of Holocalyx balansae and Zollernia magnifica; and (5) vascular bundles surrounded by lignified fibers in Harleyodendron unifoliolatum. These anatomical characters are discussed according to their possible phylogenetic implications. [ABSTRACT FROM AUTHOR]

The processes allowing evolutionary transitions in resources used by parasitic wasps are largely unknown. Microhymenopteran communities associated with figs could provide a model system to investigate such transitions. We investigate here a species of genus Idarnes. The larvae generally develop as inquilines of the pollinating wasp larvae. However, in figs where the parasitic pressure is high, eggs are laid in developing seeds. These eggs turn into small males. This is the first report of seed consumption by a fig wasp. Using an alternative resource to produce small males could provide a pathway to select for increased ability to use this resource and hence provide an intermediate step for evolving the capacity to use new resources. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 92, 9–17. [ABSTRACT FROM AUTHOR]

Abstract: Sciatic axotomy in 2-day-old rats (P2) causes lumbar motoneuron loss, which could be associated with nitric oxide (NO) production. NO may be produced by three isoforms of synthase (NOS): neuronal (nNOS), endothelial (eNOS) and inducible (iNOS). We investigated NOS expression and NO synthesis in the lumbar enlargement of rats after sciatic nerve transection at P2 and treatment with the antioxidant melatonin (sc; 1mg/kg). At time points ranging from P2 to P7, expression of each isoform was assessed by RT-PCR and immunohistochemistry; catalytic rates of calcium-dependent (nNOS, eNOS) and independent (iNOS) NOS were measured by the conversion of [3H]l-arginine to [3H]l-citrulline. All NOS isoforms were expressed and active in unlesioned animals. nNOS and iNOS were detected in some small cells in the parenchyma. Only endothelial cells were positive for eNOS. No NOS isoform was detected in motoneurons. Axotomy did not change these immunohistochemical findings, nNOS and iNOS mRNA expression and calcium-independent activity at all survival times. However, sciatic nerve transection reduced eNOS mRNA levels at P7 and increased calcium-dependent activity at 1 and 6h. Melatonin did not alter NOS expression. Despite having no action on NOS activity in unlesioned controls the neurohormone enhanced calcium-dependent activity at 1 and 72h and reduced calcium-independent catalysis at 72h in lesioned rats. These results suggest that NOS isoforms are constitutive in the neonatal lumbar enlargement and are not overexpressed after sciatic axotomy. Changes in NO synthesis induced by axotomy and melatonin administration in the current model are discussed considering some beneficial and deleterious effects that NO may have. [Copyright &y& Elsevier]

Abstract: Oxidative stress has been implicated in motoneuron death secondary to axotomy in the neonatal period. We studied the effect of sciatic transection at P2 on the motoneuron population in the lumbar enlargement of newborn rats looking for a protective role of daily doses of the antioxidant melatonin. The animals were allowed to survive from P2 to P7, and the spinal cords were processed for immunohistochemistry for superoxide dismutase (SOD) isoforms 1 and 2 and nitric oxide synthase (nNOS) (at 2, 3, 5, and 7 days post-natum), histological neuron counting and immunoblotting for the SOD isoforms (both at 2, 3, and 7 days post-natum). Melatonin reduced by 75% motoneuron loss due to axotomy at P3 and P7. Neither sciatic transection nor melatonin induced any detectable changes in the immunoreactivity patterns of the enzymes. SOD1 was expressed diffusely in the cytoplasm of neurons and ependyma and in the nuclei of presumed glial cells from P2 to P7. SOD2 was detected in neurons and ependyma and its expression was similar to SOD1 at P2 but decreased later to a spotty cytoplasmic pattern in motoneurons. nNOS was localized to the cytoplasm of a few small cells in the ventral and dorsal horns and around the central canal. Immunoblotting at 1 day postaxotomy detected a significant increase in SOD1 expression in melatonin-treated axotomized rats and a decrease in controls after axotomy and vehicle. Blotting for SOD2 did not show significant changes between groups at any time. This study provides the first evidence that SOD2 immunostaining pattern varies during motoneuron postnatal development and that melatonin alters the expression of SOD1 in the present model of peripheral nerve injury. [Copyright &y& Elsevier]

Caesalpinia echinata and C. ferrea var. ferrea have different seed behaviours and seed and fruit types. Comparison of the seed ontogeny and anatomy partly explained the differences in seed behaviour between these two species of Brazilian legumes; some differences were also related to fruit development. The seed coat in C. ferrea consisted of two layers of osteosclereids, as well as macrosclereids and fibres, to form a typical legume seed coat, whereas C. echinata had only macrosclereids and fibres. In C. echinata, the developing seed coat had paracytic stomata, a feature rarely found in legume seeds. These seed coat features may account for the low longevity of C. echinata seeds. The embryogeny was similar in both species, with no differences in the relationship between embryo growth and seed growth. The seeds of both species behaved as typical endospermic seeds, despite their different morphological classification (exendospermic orthodox seeds were described for C. echinata and endospermic orthodox seeds for C. ferrea). Embryo growth in C. ferrea accelerated when the sclerenchyma of the pericarp was developing, whereas embryonic growth in C. echinata was associated with the conclusion of spine and secretory reservoir development in the pericarp. Other features observed included an endothelial layer that secreted mucilage in both species, a nucellar summit, which grew up into the micropyle, and a placental obturator that connected the ovarian tissue to the ovule in C. ferrea. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 146, 57–70. [ABSTRACT FROM AUTHOR]

The activity and expression of nitric oxide synthase (NOS) isoforms and protein nitrotyrosine (NT) residues were investigated in whole encephalic mass (WEM) homogenates during the development of experimental allergic encephalomyelitis (EAE) in Lewis rats. EAE stages (0–III) were daily defined by clinical evaluation, and in the end of each stage, WEMs were removed for analysis of NOS activity, protein NT residues and mRNA for the different NOS isoforms. In the presence of NADPH, WEMs from EAE-III rats showed lower Ca2+-dependent NOS activity than those from control group. These differences disappeared in the presence of exogenous calmodulin, flavin adenine dinucleotide (FAD), tetrahydrobiopterin (BH4) and NADPH. Of all the cofactors, just the omission of FAD caused comparable decrease of Ca2+-dependent NOS activity from both groups. Ca2+-independent NOS activity from EAE-III animals was insensitive to the omission of any of the cofactors, while in control animals this activity was significantly inhibited by the omission of either FAD or BH4. Increased levels of both iNOS mRNA and protein NT expression were observed in animals with EAE, which also showed lower levels of a thermolabile NOS inhibitor in WEM homogenates and sera than controls. In conclusion, during late EAE stages, constitutive Ca2+-dependent NOS activity decreases concomitantly with iNOS upregulation, which could be responsible for the high protein NT levels. The differential dependence of iNOS activity on cofactors and the absence of an endogenous thermolabile NOS inhibitor in animals with EAE could reflect additional control mechanisms of NOS activity in this model of multiple sclerosis. [Copyright &y& Elsevier]

The androecium of Melastomataceae presents notable modifications in its merosity, morphology between whorls and in prolonged connectives and appendages. We carried out a comparative study of six Melastomataceae species to shed light on the developmental processes that originate such stamen diversity. The development of stamens was studied using scanning electron microscopy and histological observations. The stamens of all species studied have a curved shape because they emerge on a plane displaced by the perigynous hypanthium. They are the last flower organs to initiate and therefore their growth is inwards and towards the floral center. Despite the temporal inversion between carpels and stamens in Melastomataceae, the androecium maintains the centripetal pattern of development, the antepetalous stamens emerging after antesepalous stamens. The isomerous androecium can be the result of abortion of the antepetalous stamens, whereas heterostemony seems to be caused by differences in position and the stamen development time. Pedoconnectives and ventral appendages originate from the basal expansion of the anther late in floral development. The delay in stamen development may be a consequence of their dependence on the formation of a previous space so that they can grow. Most of the stamen diversity is explained by the formation of the connectives and their appendages. The formation of a basal-ventral anther prolongation, which culminates in the development of the pedoconnective, does not differ from other types of sectorial growth of the connective, which form shorter structures. [ABSTRACT FROM AUTHOR]

The Swartzia species are commonly known as bloodwood due to the red exudate released from the stem after injury. This exudate has aroused great interest, and an integrative study is essential to describe it in detail. Thus, this work aimed to identify the red exudate's secreting-site in S. flaemingii and S. langsdorffii, and determine if it is a latex or a resin. Samples of the stem bark and the secondary xylem were prepared for histological analysis. Fresh exudates were dissolved in deuterated methanol and analyzed by 1H-NMR; other samples were resuspended in MeOH:H2O (9:1), partitioned with organic solvents and analyzed by direct infusion mass spectrometry. Total phenolic and total flavonoid contents were determined spectrophotometrically, and antioxidant capacity was determined using ferric reducing antioxidant power assay. The results showed that the exudate is a red latex produced by articulated laticifers located among the phloem cells. The latex is composed of sucrose, catechin glucosides, chlorophyll derivatives, and hederagenin-type saponins. Both samples of S. flaemingii and S. langsdorffii presented high amounts of phenolics and flavonoids, as well as a strong antioxidant capacity. The anatomical study showed that the secreting-site of the Swartzia red exudates were laticifers. This finding allows us to exclude other substances such as resin or oleoresin, generally produced by secretory cavities or ducts. Furthermore, since laticifers are rare in Fabaceae, this finding is significant, and represents an essential taxonomic feature. The showy red color is due to the large amounts of flavonoids. This latex probably has a protective role against microorganisms and photodamage. The bioactive potential of this exudate inspires further studies, which may boost the economic importance of Swartzia. [ABSTRACT FROM AUTHOR]

Small flowers with tubular calyces and connate stamens, a small number of whorls and organs per whorl are found in species of the tribe Cecropieae (Urticaceae). This study elucidates the processes that lead to such floral conditions by comparing the morphology of the developing flowers of Cecropia pachystachya, Coussapoa microcarpa and Pourouma cecropiifolia. Buds and flowers were examined under scanning electron and light microscopy. The tubular calyx originates from the activity of a peripheral annular meristem that results in a tube with two or three lobes. In the staminate floral meristem, the androecium primordium arises as a central bulge that elongates and originates two stamens with the filaments basally or totally united; the anthers can also be united. In the pistillate floral meristem, the gynoecium primordium also arises as a central bulge that elongates and originates two carpel primordia: one expands, forming a cleft and an ovule, and the other does not differentiate and remains rudimentary. Pistillate and staminate flowers result from the absence of the stamen or carpel, respectively, from inception. Petals are also absent from inception. The formation of the tubular calyx and connate stamens occurs very early in development, characterizing a congenital union. The union of anthers by the connectives in C. microcarpa is postgenital and occurs between epidermal cell walls through a weak cohesion. The floral development of Cecropieae is quite similar and less labile than in the other Urticaceae species. [ABSTRACT FROM AUTHOR]

The presence of mucilage cells in plants, studied mainly in vegetative organs, is a condition shared by several taxonomic groups and aspects related to their diversity have been discussed with systematic purposes. This study explores the flower distribution and classification of mucilage cells in Rosales species, with inferences about flower functions. Floral buds from fifty-seven species representing seven of nine families recognized in the Rosales were sampled and processed for light and transmission electron microscopy. Mucilage cells were found in about 40% of the studied species of Cannabaceae, Rhamnaceae, Ulmaceae, and Urticaceae families, whereas no floral mucilage cells were found in species of Elaeagnaceae, Moraceae, and Rosaceae. Mucilage cells were found in the epidermis and internal tissues of many organs of different floral morph types. There is a great diversity of forms of presentation of mucilage in cells, from smaller individualized single cells to very bulky cells and to completely filled mucilage reservoirs. In some cases, cells with mucilage apparently in the cell wall and others with mucilage in the vacuole seem to occur side by side. This diversity challenges the existing classifications of mucilage cells and reinforces the importance of ontogenetic and ultrastructural studies following the path of mucilage in cells in order to propose a more natural classification and to elucidate the evolution of mucilage cells in plants. [ABSTRACT FROM AUTHOR]

We evaluated the floral development of Hymenaea verrucosa, the only African species of the genus. This species has unusual floral features, such as a tetramerous calyx, a corolla with three normal and two vestigial petals and stamens of different sizes. We analysed floral buds and flowers under scanning electron microscopy and light microscopy. The results indicated that sepals initiate helically and the petals initiate simultaneously, but the two abaxial ones develop more rapidly. In the intermediate stage, the abaxial petals stop growing and the three adaxial ones continue to develop until anthesis. Ten stamens of different sizes are distributed in two whorls, in which the antesepalous stamens are initiated before the carpel in a modified unidirectional order and the antepetalous stamens are initiated in a simultaneous order after the carpel. We speculate that the difference in size between the stamens may be related to changes in floral architecture due to the availability of space provided by the abortion of the abaxial petals. The ovary has glandular and non-glandular trichomes that overlie a broad base and a stipe with central insertion. Several secretory structures were found: secretory cavities; papillose phenolic epidermis; mucilaginous idioblasts; secretory trichomes and an annular nectary. The calyx is tetramerous as result of fusion of the two adaxial sepals. The two vestigial abaxial petals and a more pronounced growth of the abaxial stamens characterize the flower as zygomorphic. [ABSTRACT FROM AUTHOR]

The mulberry and fig family (Moraceae) has tiny flowers with a single whorled or absent perianth and inner whorls with a reduced number of organs. Relevant questions about this reduced floral structure still remain unresolved. Thus, we studied the ontogenic processes that culminate in such a reduced flower, as well as the close relationship between the floral envelope and the androecium in Brosimum gaudichaudii , Castilla elastica , Clarisia ilicifolia , Maclura tinctoria and Morus nigra . Flower buds and flowers were processed for surface (scanning electron microscopy) and anatomical (light microscopy) analyses. The perianth consists of sepals, except the flowers of B. gaudichaudii and C. elastica (staminate), in which the perianth is lacking. The staminate flower of B. gaudichaudii exhibits a bracteole enveloping the stamens. In monochlamydeous flowers the order of sepal initiation is helical or asynchronous. No petals are initiated. The calyx displays different degrees of synorganization being united only basally or along its entire extension. The sepals can have tector and glandular trichomes or only tector trichomes. Laticifers, phenolic and crystalliferous idioblasts occur in the sepal mesophyll. Stamens initiate concomitant with the pistillode in B. gaudichaudii and after initiation of the pistillode in M. tinctoria and M. nigra. In C. ilicifolia there is no pistillode and the stamens initiate after the sepals. The stamens show variation in filament shape and connective structure. The filament is inflexed in M. tinctoria and M. nigra and straight in the other species, although these structures are anatomically similar. The connective is expanded (except in M. nigra and C. ilicifolia ) and has phenolic idioblasts. We conclude that the tiny flowers of these species result of two distinct ontogenetic pathways: absence of organs from the inception and by abortion, mechanisms that act to decrease the number of floral whorls as well as the number of organs in each whorl. [ABSTRACT FROM AUTHOR]

Apomixis, the asexual formation of seeds, seems to be a reproductive alternative for many angiosperms, involving various pathways with different genetic and ecological consequences. It  is common in some megadiverse tropical groups such as Melastomataceae, of which approximately 70% of the species studied so far in the tribe Miconieae are autonomous apomictics. Hence, Miconia appears to be a good model for the study of the embryological pathways associated with apomixis. In the present study, we analyzed the polyploid and autonomous apomictic M. fallax and compared its embryology to that of the diploid and sexual M. pepericarpa, both treelets species common in the Cerrado, the Neotropical savanna areas of Central Brazil. Ovule structure and basic megasporogenesis and megagametogenesis events were similar in both species. However, M. fallax showed exclusive features associated with apomixis: aposporous embryo sac development, with the parthenogenetic development of unreduced egg cells, autonomous endosperm formation, nucellar embryony and polyembryony. Moreover, both gametophytic and sporophytic apomixis occurred in parallel to the development of a sexual embryo sac, a rarely described condition, which probably confers a great reproductive flexibility to the species. [ABSTRACT FROM AUTHOR]

Premise of research. The flower of Leandra melastomoides (Melastomataceae) exhibits a singular condition that is the presence of two distinct and opposite portions in the sepals forming what is known as a double calyx. These portions may correspond to individual sepals, explaining the recognition of two calyx whorls. No studies resolving this structure are available in the literature. Thus, we aimed to elucidate the nature of the double calyx of L. melastomoides by analyzing its ontogeny. This approach allowed us to test hypotheses about how this structure developed. Methodology. Flowers and buds were preserved and prepared for observation in LM and SEM. Pivotal results. The sepals originate in the margin of the floral apex as six spherical primordia in a single outer whorl. The growth is unidirectional until a basal protuberance arises on the ventral surface of each primordium, which allows us to distinguish an upper and a lower part of this structure. The upper portion later takes on a dorsal position. The lower portion shows laminar growth, various vascular traces, and nonglandular emergences. The dorsal portion becomes conical, is lined with nonglandular emergences, and is supplied by a single vascular trace. The vascularization of each part of a sepal has a common origin from the radial divergence of the same trace that emerges from the vascular ring of the hypanthium. Conclusions. The calyx of L. melastomoides actually consists of only one whorl, because both dorsal and laminar parts of a sepal originate from a single primordiumin a peripheral region of the floral meristem. The dorsal projection is similar to that described in the literature under the term Vorläuferspitze. The understanding of the existence of two distinct ontogenetic modules for the same organ allows us to compare it with other organs and taxonomic groups and to search for a better descriptive terminology for the structure in this group. [ABSTRACT FROM AUTHOR]

Mentha piperita L. (peppermint) possesses antimicrobial properties, but little is known of its ability to modulate macrophages. Macrophages are essential in bacterial infection control due to their antimicrobial functions and ability to link the innate and adaptive immune responses. We evaluated the effects of the peppermint leaf hydroalcoholic extract (LHAE) on cultured murine peritoneal macrophages stimulated or not with lipopolysaccharide (LPS) in vitro. Vehicle-treated cells were used as controls. The constituents of the extract were also identified. Epicatechin was the major compound detected in the LHAE. LPS-induced macrophage death was reversed by incubation with LHAE (1-30 μg/ml). Higher concentrations of the extract (≥100 μg/ml) decreased macrophage viability (49-57%) in the absence of LPS. LHAE (1-300 μg/ml) attenuated H2O2 (34.6-53.4%) but not nitric oxide production by these cells. At similar concentrations, the extract increased the activity of superoxide dismutase (15.3-63.5-fold) and glutathione peroxidase (34.4-73.6-fold) in LPS-treated macrophages. Only LPS-unstimulated macrophages presented enhanced phagocytosis (3.6-6.6-fold increase) when incubated with LHAE (3-30 μg/ml). Overall, the LHAE obtained from peppermint modulates macrophage-mediated inflammatory responses, by stimulating the antioxidant pathway in these cells. These effects may be beneficial when the excessive activation of macrophages contributes to tissue damage during infectious disease. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Although the ovary position is considered a stable character in angiosperms, Melastomataceae species have perigynous flowers in which the ovary varies from superior to inferior. Thus, we investigated the ontogenetic process involved in variation of the ovary position in Melastomataceae. We focused on histogenesis of the floral apex in search of developmental patterns for each type of ovary position. METHODS: Six species in which the ovary varies from superior to inferior were chosen: Henriettea saldanhae, L eandra melastomoides, Miconia dodecandra, Microlicia euphorbioides, Rhynchanthera grandiflora, and Tibouchina clinopodifolia. Buds and flowers were processed for surface and histological examinations. KEY RESULTS: The floral apex changes from convex to concave, resulting in a perigynous hypanthium. Cell divisions in the margins of the floral apex form an annular intercalary meristem that elevates the base of the primordia of almost all whorls. The joint growth of the carpel base with the gynoecial hypanthium originates semi-inferior ovaries in Leandra melastomoides, Miconia dodecandra, and Tibouchina clinopodifolia and inferior ovaries in Henriettea saldanhae. In Microlicia euphorbioides and Rhynchanthera grandiflora, the carpels are not affected by this hypanthial growth; flowers have a superior ovary. CONCLUSIONS: Changes in ovary position of Melastomataceae are due to intercalary meristematic activity, which is one of the main mechanisms for the origin of morphological innovations among plants. Our data illustrate the importance of the intercalary meristems in floral development, and we discuss the implications of this ontogenetic model for understanding the evolution of ovary position in Melastomataceae. [ABSTRACT FROM AUTHOR]

The six distinct gland types described in Mimosoideae anthers vary from simple projections to robust and vascularized structures. The origin of these glands is attributed to an extension of connective. However, except for an illustrative recording of some developmental stages, nothing is known about the origin and gland development, which prevents their correct classification. This study aimed to elucidate the ontogeny of four of the six gland types detected in the anthers of Mimosoideae. The intention was to understand whether the morphological diversity results from different ontogenetic processes. For this, flower buds of various sizes of four Mimosoideae species with different types of glands were collected : Stryphnodendron adstringens (Piptadenia subtype Piptadenia), Tetrapleura tetraptera (Piptadenia subtype Adenanthera), Adenanthera pavonina (Piptadenia subtype Entada), and Pentaclethra macroloba (Pentaclethra type). The samples were processed for surface (scanning electron microscopy) and anatomical analyses (light microscopy). Despite their morphological differences, the glands share a common meristematic origin. They arise from simultaneous divisions in the first three layers of meristematic cells that cover the apical portion of the young anther. After the formation of the protuberance, the developing glands undergo different specialized processes that include (1) elongation of the epidermal cells in Piptadenia subtype Adenanthera and Piptadenia subtype Entada, (2) degradation of central gland cells in Piptadenia subtype Entada, (3) change from a rounded to a triangular shape in the Pentaclethra type, and (4) cell differentiation into a procambial meristem and subsequently into vascular tissue in the Pentaclethra type, resulting in the diversity encountered in the group. Their origin from protodermal and fundamental meristem cells characterizes the anther glands as emergences. Our data indicate a conserved meristematic origin of glands, favoring the hypothesis of homology of these structures and supporting the monophyly of the Mimosoideae clade. [ABSTRACT FROM AUTHOR]

Introduction:Acute pancreatitis (AP) may be severe and cause hospitalization or death, and the available treatment is insufficient to control pancreatic inflammation and pain. Rutin is a natural flavonoid with the potential to treat AP via anti-inflammatory, antinociceptive, and antioxidant activities. Aim:This study investigated the beneficial effects of rutin on experimental AP induced byl-arginine administration in mice. Methods:Thel-arginine-induced AP model was used in Swiss mice (n = 6–8). Mice submitted to AP induction were treated with rutin (37.5, 75, or 150 mg kg−1, p.o.) or vehicle (saline) after 24, 36, 48, and 60 h of AP induction. Abdominal hyperalgesia, serum enzymes, interleukin (IL)-6 levels, pancreatic inflammatory parameters, malondialdehyde (MDA) levels, antioxidant enzyme activities, and 3-nitrotyrosine contents were measured 72 h after induction. Results:Mice submitted tol-arginine injections developed abdominal hyperalgesia and increased serum amylase, lipase, C-reactive protein and IL-6 concentrations; and increased pancreatic myeloperoxidase activity, edema index, MDA, and 3-nitrotyrosine contents. A marked decrease in catalase activity was observed in the pancreas without alterations of superoxide dismutase (SOD) activity compared with the control group. Rutin treatment significantly impaired all the parameters that were altered by AP induction, but increased catalase and SOD activities in the pancreas compared with the vehicle-treated group. Conclusion:Rutin treatment exerted a protective effect onl-arginine-induced AP by mechanisms involving the reduction of oxidative stress, which suggests that this flavonoid has a potential for future approaches designed for the management of AP. [ABSTRACT FROM PUBLISHER]

Summary 1. The aim of the present study was to examine the effects of long-term nitric oxide (NO) blockade on contractions of the rat ileum induced by muscarinic agonists. 2. Male Wistar rats received the NO synthesis inhibitor N G -nitro-l-arginine methyl ester (l-NAME; 20 mg/rat per day) in drinking water for 7, 15, 30 and 60 days. Concentration–responses curves to methacholine and carbachol were obtained and pEC50 values were calculated. Saturation binding assays were performed in membranes prepared from rat ileum after 60 days of l-NAME treatment and the dissociation constant (KD ) and maximal number of binding sites (Bmax ) were determined by Scatchard analysis. 3. The NO synthase activity of the ileum was markedly reduced in all l-NAME-treated groups. At 60 days after l-NAME treatment, a significant increase in the potency of methacholine (fourfold) and carbachol (threefold) was observed. In binding studies, we found a significant increase in Bmax for [3 H]-quinuclidinyl benzilate of approximately 57% in the l-NAME treated group without any significant change in KD values. The contractile response to methacholine was not modified by the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (3 µmol/L). No morphological alterations in the rat ileum were observed in l-NAME-treated rats. 4. Our findings suggest that treatment with l-NAME for 60 days induces a marked increase in the potency of methacholine and carbachol, as well as an increase in receptor number in the rat ileum. [ABSTRACT FROM AUTHOR]