Caveolin-1 influences mitochondrial plasticity and function in hepatic stellate cell activation.

Caveolin-1 (Cav-1) is an integral membrane protein present in all organelles, responsible for regulating and integrating multiple signals as a platform. Mitochondria are extremely adaptable to external cues in chronic liver diseases, and expression of Cav-1 may affect mitochondrial flexibility in hepatic stellate cells (HSCs) activation. We previously demonstrated that exogenous expression of Cav-1 was sufficient to increase some classical markers of activation in HSCs. Here, we aimed to evaluate the influence of exogenous expression and knockdown of Cav-1 on regulating the mitochondrial plasticity, metabolism, endoplasmic reticulum (ER)-mitochondria distance, and lysosomal activity in HSCs. To characterize the mitochondrial, lysosomal morphology, and ER-mitochondria distance, we perform transmission electron microscope analysis. We accessed mitochondria and lysosomal networks and functions through a confocal microscope and flow cytometry. The expression of mitochondrial machinery fusion/fission genes was examined by real-time polymerase chain reaction. Total and mitochondrial cholesterol content was measured using Amplex Red. To define energy metabolism, we used the Oroboros system in the cells. We report that GRX cells with exogenous expression or knockdown of Cav-1 changed mitochondrial morphometric parameters, OXPHOS metabolism, ER-mitochondria distance, lysosomal activity, and may change the activation state of HSC. This study highlights that Cav-1 may modulate mitochondrial function and structural reorganization in HSC activation, being a potential candidate marker for chronic liver diseases and a molecular target for therapeutic intervention.

Manejo de la intoxicación por celidonia (Chelidonium Majus L) en los servicios de Urgencias / Management of greater celandine (Chelidonium Majus L) intoxication in Emergency services

La planta de celidonia crece salvaje en nuestro medio y se vende libremente en internet. Se utiliza en la medicina tradicional china y en fitoterapia, por ejemplo, para diversas enfermedades cutáneas, como antiinflamatorio y como antiespasmódico. Su ingesta puede provocar toxicidad, en forma de insuficiencia renal aguda, tetania, paresias o hepatitis aguda, entre otros. Tras la revisión bibliográfica, recomendamos realizar en los servicios de Urgencias una exploración física completa del paciente, análisis de sangre (incluyendo hematimetría con fórmula, coagulación y bioquímica con iones (sodio, potasio, calcio), albúmina, creatinina, urea, transaminasas, bilirrubina, lactato deshidrogenasa) y de orina. Dado que no se dispone de un antídoto específico, el tratamiento será sintomático y de soporte. Si el paciente permanece asintomático, se recomienda observación durante 4-6 horas. (AU)

Greater celandine is a plant that grows wild in our area and it is sold freely on the web. It is used in traditional Chinese medicine and in phytotherapy, for example, to treat several dermatological disorders, as anti-inflammatory and as antispasmodic. If ingested, it can produce toxicity, as acute kidney injury, tetany, paresis or acute hepatitis, among others. After our bibliographical review, we recommend that a complete physical examination to the patient is performed in Emergency service, blood test —including hematometry, coagulation and biochemistry which includes ions (sodium, potassium and calcium), also albumin, creatinine, urea, transaminases, bilirubin, lactate dehydrogenase (LDH)— and a urine test.A specific antidote is not available; therefore, treatment will be symptomatic and supportive. If the patient remains asymptomatic, we recommend observation for 4-6 hours. (AU)

Previous herbivory alerts conspecific gravid sawflies to avoid unsuitable host plants.

The willow sawfly, Nematus oligospilus (Förster), is a pest in Salix commercial forests and has been reported worldwide. Female adults must recognize a suitable host plant to oviposit, since her offspring lack the ability to move to another host. We evaluated the effect of conspecific herbivory on the oviposition choices of N. oligospilus females by providing damaged (DP) and undamaged (UP) plants of Salix humboldtiana, a native willow from South America, as oviposition substrates. Local and systemic effects were studied. For the local treatment, a twig from the DP with damaged leaves was contrasted to a twig from a UP in dual choice experiments. For systemic treatment, a twig from the DP with intact leaves was contrasted to a twig from a UP. We estimated the use of olfactory and contact cues by comparing volatile emission of DP and UP, and by analysing the behaviour of the females during host recognition after landing on the leaf surface. In the context of the preference-performance hypothesis (PPH), we also tested if oviposition site selection maximizes offspring fitness by evaluating neonate hatching, larval performance and survival of larvae that were born and bred on either DP or UP. Our results demonstrate that previous conspecific herbivory on S. humboldtiana has a dramatic impact on female oviposition choices and offspring performance of the sawfly N. oligospilus. Females showed a marked preference for laying eggs on UP of S. humboldtiana. This preference was found for both local and systemic treatments. Volatile emission was quantitatively changed after conspecific damage suggesting that it could be related to N. oligospilus avoidance. In the dual choice preference experiments, the analysis of the behaviour of the females once landing on the leaf surface suggested the use of contact cues triggering egg laying on leaves from UP and avoidance of leaves from DP. Furthermore, 48 h of previous conspecific feeding was sufficient to dramatically impair neonate hatching, as well as larval development and survival, suggesting a rapid and effective reaction of the induced resistance mechanisms of the tree. In agreement with the PPH, these results support the idea that decisions made by colonizing females may result in optimal outcomes for their offspring in a barely studied insect model, and also opens the opportunity for studying tree-induced defences in the unexplored South American willow S. humboldtiana.

Yeast derivatives and wheat germ in the adult diet modulates fecundity in a tephritid pest.

Anastrepha fraterculus (Wiedemann), a pest of great economic importance in South America, needs urgently to be controlled by environmentally friendly methods such as the sterile insect technique for which mass rearing of insects is required. Because oogenesis takes place during the adult stage, mass-rearing facilities should provide the females a diet that maximizes egg production at the lowest cost. Accordingly, we investigated the effect of artificial protein sources in the adult diet (yeast derivatives of different cost but with similar amino acids profiles, and the addition of wheat germ) on fecundity. Additionally, we evaluated different ratios of yeast derivatives or wheat germ on ovary maturation, fecundity, and fertility as well as their association with the nutrient content of females. Females fed hydrolyzed yeast and yeast extract attained the highest fecundity level, and those fed brewer's yeast the lowest. Reducing the amount of hydrolyzed yeast, an expensive protein source, in the diet negatively affected fecundity and ovary maturation. Increasing the amount of brewer's yeast, a low-cost protein source, did not favor fecundity. The addition of wheat germ in the adult diet improved fecundity regardless of the yeast derivate considered. Percentage of egg hatch was not affected by the diet. Nutrient content of A. fraterculus females varied according to the adult diet provided and mating status. Our findings provide novel baseline information to understand the role of nutrition on reproductive performance of A. fraterculus females and are discussed in the context of resource allocation. They also provide valuable advances in the search for cost-effective adult diets at fruit fly mass rearing facilities.

Male sexual enhancement after methoprene treatment in Anastrepha fraterculus (Diptera: Tephritidae): A sustained response that does not fade away after sexual maturation.

The juvenile hormone (JH) of insects triggers physiological changes related to reproduction in adults of both sexes. Methoprene is a sesquiterpene with some effects that are analogous to those of JH. Treatments with methoprene accelerate sexual maturation in males of the South American fruit fly Anastrepha fraterculus, giving young males a mating advantage over non-treated males of the same age. Here, we evaluated the effects of methoprene treatment on A. fraterculus males after the sexual maturation phase and tested whether this compound provides a long-term mating advantage. Moreover, we took the first step to unravel the mechanisms that underlie male sexual enhancement. We treated males 1day or 8days after adult emergence and compared mate choice between recently matured (young) females and females that had been mature for ca. 10days (aged females). We also addressed methoprene treatment effects on male sexual signalling. We found that methoprene treatment enhanced male sexual competitiveness even after the sexual maturation phase, and the effect did not decrease until males were older than 20days. However, when methoprene treatment was carried out close to sexual maturity, the mating enhancement was no longer observed, suggesting a non-immediate effect and excluding the possibility that methoprene acts as a pheromonal compound. Young and aged females tended to mate more frequently with treated-males. This might indicate that in a context of sexual selection, the potential benefits associated with reproductive success would be similar for females of both ages. Treated males released larger amounts of pheromonal compounds than non-treated males, but their courtship behaviour was not altered to the same extent, suggesting that methoprene treatment may accelerate differently the components of male courtship. We discuss potential benefits of using methoprene to increase the efficiency of the sterile insect technique, which is an environmentally safe method to control this important South American fruit pest.

Differences in sperm storage and remating propensity between adult females of two morphotypes of the Anastrepha fraterculus (Diptera: Tephritidae) cryptic species complex.

The South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species composed of at least seven morphotypes. Some of them, such as the Peruvian and Brazilian 1 morphotypes (which include Argentinean populations), exhibit strong pre-copulatory isolation, yet it is possible to obtain heterotypic crosses when forcing copulation of adults under laboratory conditions. The cross involving Peruvian males and Argentinean females produces F1 offspring with reduced viability in terms of egg hatch. This low hatchability could be caused by a reduced amount of sperm transferred to and stored by females mated with heterotypic males, which in turn could affect their post-copulatory behaviour. To test these hypotheses, we investigated sperm transfer and female mating and remating behaviour for homotypic and heterotypic crosses between adults of two morphotypes (Brazilian 1 [Argentina] and Peruvian [Peru]) of the A. fraterculus cryptic species complex. As reported before, Argentinean males and females mated earlier in the day than the other three mating combinations. Peruvian females engaged in shorter copulation times than Argentinean females. Peruvian females tended to store smaller quantities of sperm than Argentinean females, and almost a half of the crosses involving Argentinean males and Peruvian females were unsuccessful (no sperm transfer). However, there was no evidence that the cross between Peruvian males and Argentinean females resulted in storage of a critically small amount of sperm (posing risk of sperm shortage). Argentinean females were more willing to remate than Peruvian females, irrespective of male morphotype, but latency to remating was not affected by male or female morphotype. This study shows that mating behaviour differs between some of the A. fraterculus complex morphotypes, with female but not male morphotype determining female likelihood to remate.

Spatial and temporal variation in Chaetanaphothrips orchidii Moulton (Thysanoptera: Thripidae) population and its damage on lemon.

Chaetanaphothrips orchidii Moulton has recently been detected in lemon (Citrus limon) orchards in northwest Argentina, causing high levels of damage on fruits. Severe damage results in the rejection of fruit for export, which must then be sold in the industry. However, the restrictions imposed by the citrus industry on insecticide residues sometimes also result in fruit rejection. Here, we studied the ecology and behavior of C. orchidii in order to propose a pest management strategy that could meet both export and industry demands. Seasonal occurrence and canopy distribution of C. orchidii in lemon orchards were evaluated, and field experimental manipulations of thrips populations were performed to analyze how the length (45, 100, 130, and 200 days) and timing (January, February, or March) of C. orchidii activity related with fruit damage. Lemons harvested during summer showed lower infestation levels (∼0.64 individual per fruit) than those harvested in winter (∼1.88 individuals per fruit). Higher proportions of damaged fruits were recorded in the lower part of the tree. Changes in the population levels of C. orchidii were closely associated with fruit phenology. The longer the lemon fruits were exposed to the thrips, the higher was the damage. However, the time of infestations did not affect fruit damage. Our data provide a first step towards understanding the factors that determine the severity of fruit damage caused by C. orchidii in northwest Argentina.

Mating compatibility among four pest members of the Bactrocera dorsalis fruit fly species complex (Diptera: Tephritidae).

Bactrocera dorsalis (Hendel), Bactrocera papayae Drew & Hancock, Bactrocera philippinensis Drew & Hancock, and Bactrocera carambolae Drew & Hancock are pest members within the B. dorsalis species complex of tropical fruit flies. The species status of these taxa is unclear and this confounds quarantine, pest management, and general research. Mating studies carried out under uniform experimental conditions are required as part of resolving their species limits. These four taxa were collected from the wild and established as laboratory cultures for which we subsequently determined levels of prezygotic compatibility, assessed by field cage mating trials for all pair-wise combinations. We demonstrate random mating among all pair-wise combinations involving B. dorsalis, B. papayae, and B. philippinensis. B. carambolae was relatively incompatible with each of these species as evidenced by nonrandom mating for all crosses. Reasons for incompatibility involving B. carambolae remain unclear; however, we observed differences in the location of couples in the field cage for some comparisons. Alongside other factors such as pheromone composition or other courtship signals, this may lead to reduced interspecific mating compatibility with B. carambolae. These data add to evidence that B. dorsalis, B. papayae, and B. philippinensis represent the same biological species, while B. carambolae remains sufficiently different to maintain its current taxonomic identity. This poses significant implications for this group's systematics, impacting on pest management, and international trade.

Remating behavior in Anastrepha fraterculus (Diptera: Tephritidae) females is affected by male juvenile hormone analog treatment but not by male sterilization.

The sterile insect technique (SIT) has been proposed as an area-wide method to control the South American fruit fly, Anastrepha fraterculus (Wiedemann). This technique requires sterilization, a procedure that affects, along with other factors, the ability of males to modulate female sexual receptivity after copulation. Numerous pre-release treatments have been proposed to counteract the detrimental effects of irradiation, rearing and handling and increase SIT effectiveness. These include treating newly emerged males with a juvenile hormone mimic (methoprene) or supplying protein to the male's diet to accelerate sexual maturation prior to release. Here, we examine how male irradiation, methoprene treatment and protein intake affect remating behavior and the amount of sperm stored in inseminated females. In field cage experiments, we found that irradiated laboratory males were equally able to modulate female remating behavior as fertile wild males. However, females mated with 6-day-old, methoprene-treated males remated more and sooner than females mated with naturally matured males, either sterile or wild. Protein intake by males was not sufficient to overcome reduced ability of methoprene-treated males to induce refractory periods in females as lengthy as those induced by wild and naturally matured males. The amount of sperm stored by females was not affected by male irradiation, methoprene treatment or protein intake. This finding revealed that factors in addition to sperm volume intervene in regulating female receptivity after copulation. Implications for SIT are discussed.

Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements.

Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.

Derrame pericárdico en un caso de linfohistiocitosis hemofagocítica secundaria a leishmaniasis / Pericardial effusion in a case of hemophagocytic lymphohistiocytosis secondary to leishmaniasis

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Random mating and reproductive compatibility among Argentinean and southern Brazilian populations of Anastrepha fraterculus (Diptera: Tephritidae).

As a prerequisite for area-wide application of the sterile insect technique in an area encompassing northern Argentina and southern Brazil, prezygotic and postzygotic reproductive compatibility among three geographically distant populations in the area was tested. In field cages, sexually mature adults of each population were found to be sexually compatible, mating duration was not affected by fly origin and there was no clear evidence of spatial partition of mating location. In the laboratory, homotypic and heterotypic crosses for all possible combinations displayed similar levels of fertility and yielded F1 adults without distortion of the sex ratio. Finally, F1 hybrid and parental adults produced equally viable F2 eggs. Put together, our results and those from earlier studies suggest that a large area, ranging from Buenos Aires to the surroundings of São Paulo, could be managed using a single A. fraterculus mass-reared strain. At the northern margin of this area, two A. fraterculus morphotypes appear to coexist in sympatry. We delineate future research to further delimit the distribution of the aff1 morphotype (Argentina-southern Brazil) and to gain insight into evolutionary patterns producing divergence and radiation of tropical fruit fly species.

Biological activities of ACL-I and physicochemical properties of ACL-II, lectins isolated from the marine sponge Axinella corrugata.

Lectin II from the marine sponge Axinella corrugata (ACL-II) was purified by affinity chromatography on rabbit erythrocytic stroma incorporated into a polyacrylamide gel, followed by gel filtration on Ultrogel AcA 44 column. Purified ACL-II is a lectin with an Mr of 80 kDa and 78 kDa, estimated by SDS-PAGE and by FPLC on Superose 12 HR column, respectively. ACL-II mainly agglutinates native rabbit erythrocytes and this hemagglutinating activity is independent of Ca(2+), Mg(2+) and Mn(2+), but is inhibited by d-galactose, chitin and N-acetyl derivatives, with the exception of GalNAc. ACL-II is stable for up to 65 °C for 30 min, with a better stability at a pH range of 2 to 6. In contrast, ACL-I displays a strong mitogenic and cytotoxic effect.

Management of protein intake in the fruit fly Anastrepha fraterculus.

This work tested if carbohydrates and proteins ingestion is regulated in the South American fruit fly, Anastrepha fraterculus, to optimize survival and reproduction. Adult food treatments were established by providing sugar and hydrolyzed yeast in various combinations either alone or mixed at a standard 3:1 ratio (sugar:hydrolyzed yeast). Individual food consumption was assessed and related to survival patterns. The effects of adult feeding on fecundity and fertility patterns were investigated in groups of flies. Sugar consumption was the lowest in the treatment where it was provided with hydrolyzed yeast at a fixed 3:1 ratio. Consumption of hydrolyzed yeast did not differ between this treatment and the one in which this solution was complemented with one solution of sugar. It seems that a mixture of sugar and hydrolyzed yeast at a fixed ratio of 3:1, respectively, restricts extra ingestion of sugar; most probably because of negative response of the fly to overconsumption of protein. Survival was affected by the treatments, being lower in those cases where protein was at the fixed ratio. Group experiments revealed that protein restriction expanded longevity and decreased egg production. In contrast, egg production was enhanced when flies were kept continuously with a mixture of yeast and sugar plus an extra source of sugar, and this was not in detriment of survival. Our results suggest that fixed sugar-protein ratios in which protein is in excess affects fitness components such as longevity and reproduction. These findings are discussed from a theoretical and applied perspective in the context of pest control by means of the sterile insect technique.

Anchored and soluble gangliosides contribute to myelosupportivity of stromal cells.

Stroma-mediated myelopoiesis depends upon growth factors and an appropriate intercellular microenvironment. Previous studies have demonstrated that gangliosides, produced by hepatic stromal cell types, are required for optimal myelosupportive function. Here, we compared the mielossuportive functions of a bone marrow stroma (S17) and skin fibroblasts (SF) regarding their ganglioside pattern of synthesis and shedding. The survival and proliferation of a myeloid precursor cell (FDC-P1) were used as reporter. Although the ganglioside synthesis of the two stromal cells was similar, their relative content and shedding were distinct. The ganglioside requirement for mielossuportive function was confirmed by the decreased proliferation of FDC-P1 cells in ganglioside synthesis-inhibited cultures and in presence of an antibody to GM3 ganglioside. The distinct mielossuportive activities of the S17 and SF stromata may be related to differences on plasma membrane ganglioside concentrations or to differences on the gangliosides shed and their subsequent uptake by myeloid cells, specially, GM3 ganglioside.

ACL-I, a lectin from the marine sponge Axinella corrugata: isolation, characterization and chemotactic activity.

The lectin from the marine sponge Axinella corrugata (ACL-I) was purified by affinity chromatography on rabbit erythrocytic stroma incorporated into a polyacrylamide gel followed by gel filtration on Ultrogel AcA 44 column. Purified ACL-I is a hexameric glycoprotein with a Mr of 82.3 kDa estimated by SDS-PAGE and 78.5 kDa by FPLC on Superose 12 HR column. The pI of lectin is 6.3 and ACL-I is constituted of 13.9 kDa similar subunits some of them linked by disulphide bridges. This lectin agglutinates native rabbit, goat and dog erythrocytes and in less extent human erythrocytes. The hemagglutinating activity is independent of Ca(2+), Mg(2+) and Mn(2+), but it is strongly inhibited by carbohydrates containing N-acetyl groups. ACL-I is stable up to 70 degrees C for 30 min, with optimum pH between 7 and 8, and it is also resistant to enzymatic proteolysis in vitro. In the presence of reducing or denaturant agents, the lectin activity decreases. ACL-I displays chemotactic effect on rat neutrophil in vitro which is inhibited by N-acetyl-d-glucosamine.

Reduction of gangliosides, phospholipids and cholesterol content in cerebral cortex of rats caused by chronic hypermethioninemia.

Neurological dysfunction is observed in patients with severe hypermethioninemia, whose physiopathology is still poorly understood. In the current study we investigated the effect of chronic administration of methionine on the content and species of gangliosides and phospholipids, as well as on the concentration of cholesterol in rat cerebral cortex. Wistar rats received subcutaneous injections of methionine (1.34-2.68 micromol/g of body weight), twice a day, from the 6th to the 28th day of age and controls received saline. Animals were killed 12h after the last injection. Results showed that methionine administration significantly decreased the total content of lipids in cerebral cortex of rats. We also observed that this amino acid significantly reduced the absolute quantity of the major brain gangliosides (GM1, GD1a, GD1b and GT1b) and phospholipids (sphingomyelin, phosphatidylcholine and phosphatidylethanolamine). We also showed that Na+,K+-ATPase activity and TBARS were changed in cerebral cortex of rats subjected to hypermethioninemia. If confirmed in human beings, these data could suggest that the alteration in lipid composition, Na+,K+-ATPase activity and TBARS caused by methionine might contribute to the neurophysiopathology observed in hypermethioninemic patients.