Ecological consequences when organisms avoid a contaminated environment: A study evaluating the toxicity of fipronil

The ability of aquatic organisms to sense the surrounding environment chemically and interpret these signals correctly is crucial to their survival and ecological niche. This study applied the Heterogenous Multi-Habitat Assay System - HeMHAS to evaluate the avoidance potential of Daphnia magna to detect fipronil-contaminated habitats in a connected landscape after a short (48 h), previous, forced exposure to an environmentally relevant concentration of the same insecticide. The swimming of daphnids was also analyzed by recording the total distance covered. D. magna preferred areas with less contamination, although the effect of fipronil on their swimming ability (a decrease) was observed for all the concentrations tested. The application of non-forced multi-compartment exposure methodologies is a recent trend and is ecologically relevant as it is based on how contamination can really produce changes in an organism's habitat selection. Finally, we consider the importance of more non-forced exposure approaches where Stress Ecology can be aggregated to improve systemic understanding of the risk that contaminants pose to aquatic ecosystems from a broader landscape perspective.

Physiological responses on the reproductive, metabolism and stress endpoints of Astyanax lacustris females (Teleostei: Characiformes) after diclofenac and ibuprofen exposure

Diclofenac (DCF) and ibuprofen (IBU) are pharmaceutical compounds frequently detected in aquatic compartments worldwide. Several hazard effects including developmental abnormalities and redox balance impairment have been elucidated in aquatic species, but multiple endocrine evaluations are scarce. Therefore, the present study aimed to assess the disruptive physiological effects and toxicity of DCF and IBU isolated and combined, using females of the native freshwater teleost Astyanax lacustris. In regards to NSAIDs bioavailability, the results showed absence of degradation of IBU and DCF after 7 days of exposure. IBU LC50 for A. lacustris was 137 mgL-1 and females exposed to IBU isolated increased thyroxine (T4) concentration at 24 h and decreased after 96 h; DCF exposure decreased triiodothyronine (T3) concentration at 96 h. Circulating levels of 17β-estradiol (E2), cortisol (F) and testosterone (T) were not affected by any treatment. HPG and HPI axis genes fshβ, pomc and vtg were upregulated after 24 h of IBU exposure, and dio2 was downregulated in DCF fish exposed group after 96 h compared to the mixture. Protein concentration was reduced in muscle and increased in the liver by DCF and mixtures exposures at 24 h; while liver lipids were increased in the mixture groups after 96 h. The study point out the capacity of NSAIDs to affect endocrine endpoints in A. lacustris females and induce changes in energetic substrate content after acute exposure to isolated and mixed NSAIDs treatments. Lastly, the present investigation brings new insights into the toxicity and endocrine disruptive activity of NSAIDs in Latin America teleost species and the aquatic environment.

How natural and anthropogenic factors should drive microplastic behavior and fate: The scenario of Brazilian urban freshwater

Brazil maintains its position at the top of the global ranking of plastic producers, yet recycling efforts have been incipient. Recent data reveals an annual production of approximately 14 million tons of plastic waste, not accounting for the surge in the usage of plastic masks and related materials due to the COVID-19 pandemic. However, what remains largely unreported is that over half of post-consumer plastic packaging in Brazil is managed without any monitoring, and it remains unclear how this will contribute to the occurrence of plastic waste and microplastics in Brazilian freshwaters. This scenario requires the consideration of several other crucial factors. Studies have been carried out mainly in marine and estuarine waters, while data on freshwaters are lacking. Brazil has continental dimensions and the highest water availability on the planet, yet the demand for water is greatest in regions with medium to low supply. Many densely populated Brazilian urban areas face chronic flood problems, possess inadequate levels of wastewater treatment, and display inadequate solid waste management practices. Consequently, urban freshwater with tropical characteristics in Brazil presents an intriguing scenario and is complementary to the most commonly studied marine environments. In this study, we explore the nuances of pollution in Brazilian urban freshwater and discuss how various parameters, such as organic matter, suspended solids, temperature, and pH, among others, influence the behavior of microplastics and their interactions with organic and inorganic contaminants. Furthermore, we address how microplastic conditions, such as biofouling, the type of plastic, or degradation level, may impact their behavior. By analyzing how these conditions change, we propose priority themes for investigating the occurrence of microplastics in Brazilian urban freshwater systems under different degrees of human impact. Ultimately, this study aims to establish a network dedicated to standardized monitoring of microplastic pollution in Brazilian urban freshwaters.

Insights into sorption and molecular transport of atrazine, testosterone, and progesterone onto polyamide microplastics in different aquatic matrices

Microplastics can act as vectors of a wide class of contaminants in aquatic environments. The sorption behavior of two hormones known to cause adverse effects in biota even in low concentrations (testosterone-TTR and progesterone-PGT), and a pesticide with a high environmental persistence known as endocrine disruptor chemical (atrazine-ATZ) onto polyamide (PA) microplastics is investigated under different aquatic matrices using kinetic and isotherm experiments. The sorption equilibrium is achieved in 48 h, and the experimental results are better fitted by pseudo-2nd-order model. Langmuir isotherm better describes the sorption of the contaminants onto PA microplastics. PGT presents the highest sorption efficiency at around 90%, followed by TTR at 70% and ATZ at approximately 20%. Moreover, ATZ is the contaminant with the highest desorption efficiency (∼65%), indicating its preference for staying solubilized in water. Combining classical molecular dynamics and density functional theory calculations, the sorption energies were calculated as 12-15 kcal mol^-1, 13-16 kcal mol^-1, and 19-22 kcal mol^-1 for PGT, TTR, and ATZ, respectively, showing that PGT needs less energy to be transferred from the solvent network to the PA surface, in agreement with experimental results. The sorption mechanism is driven by hydrogen bonds onto PA outer surface, while the electrostatic interactions dominate the PA inner surface sorption. Moreover, the sorption efficiency is statistically different between the investigated matrices, indicating that physicochemical characteristics of water systems could influence the interactions between PA-contaminant. In seawater, the phenomena of salting-out/in and competitive sorption with saline ions are observed for three contaminants. The PA-contaminant complexes are more polar and soluble than the dissociated ones, which increases the contaminant's co-transport by PA in water.

Short and long-term exposure to the pesticides fipronil and 2,4-D: Effects on behavior and life history of Daphnia magna

The high levels of contamination in aquatic ecosystems caused by pesticides and the organisms' consequent continuous exposure to it has made them vulnerable to damage. However, mobile organisms can avoid this continued exposure to contaminants by moving to less disturbed habitats. Therefore, through the use of the Heterogenous Multi-Habitat Assay System (HeMHAS), our objective was to evaluate the ability of Daphnia magna to detect and avoid habitats contaminated by fipronil and 2,4-D, in a spatially connected landscape. Further, the role of contamination by these pesticides, isolated and in mixtures, concerning the colonization of habitats by daphnids was also evaluated. Given that not all organisms successfully escape contamination, the chronic toxicity of the same pesticides using different parameters for D. magna (maternal survival, fecundity and maternal body length) was also evaluated. When evaluating the avoidance response by D. magna exposed to pesticides, there was no preference for the less contaminated areas for both compounds. However, organisms did not move to contaminated zones in the colonization experiments, with no immigration of daphnids to the zones with intermediate and the highest levels of fipronil, nor to the highest concentration of 2,4-D. Finally, the colonization by daphnids was significantly prevented when exposed to a mixture of the pesticides, in which the areas with the highest combinations of pesticide concentrations were not colonized by D. magna. Regarding the long-term chronic effects, negative consequences were observed, particularly for maternal body length, fecundity and maternal survival, due to the exposure to fipronil. Considering that pesticides can limit the areas colonized by organisms by making them unattractive, the risk of local population extinction may be underestimated if only standard endpoints involving forced exposure are studied.

Avoidance responses by Danio rerio reveal interactive effects of warming, pesticides and their mixtures

Temperature variations and thermal extremes events caused by climate change can have profound implications for the toxicity of pesticides in aquatic organisms. Using an innovative system (Heterogeneous Multi-Habitat Test System - HeMHAS) that allows the simulation of different scenarios within a spatially heterogeneous landscape, the effects on the habitat selection of Danio rerio fish caused by the pesticides fipronil and 2,4-D were studied as single compounds and in mixture and integrated with air temperature variation (20, 24 and 28 °C). As a result, D. rerio detected and avoided both pesticides at air temperatures of 20 and 24 °C; however, at 28 °C no significant difference was observed in habitat choice by fish. Additionally, when pesticides were mixed in a heterogeneously contaminated landscape, it was observed that D. rerio detected contamination and preferred the clean zone at 20 and 24 °C; however, at 28 °C the potential to escape from the most contaminated areas was impaired. Thus, contamination by both pesticides made the habitat selection behavior of fish at 20 and 24 °C more noticeable. In addition, the association between pesticides and temperature showed negative effects on the response of fish to detect and escape from contaminated environments, suggesting the influence of temperature in altering the ability of the organism to provide an efficient response to stress.

Foldable cones as a framework for nonrigid origami

The study of origami-based mechanical metamaterials usually focuses on the kinematics of deployable structures made of an assembly of rigid flat plates connected by hinges. When the elastic response of each panel is taken into account, novel behaviors take place, as in the case of foldable cones (f-cones): circular sheets decorated by radial creases around which they can fold. These structures exhibit bistability, in the sense that they can snap through from one metastable configuration to another. In this work, we study the elastic behavior of isometric f-cones for any deflection and crease mechanics, which introduce nonlinear corrections to a linear model studied previously. Furthermore, we test the inextensibility hypothesis by means of a continuous numerical model that includes both the extended nature of the creases, stretching and bending deformations of the panels. The results show that this phase-field-like model could become an efficient numerical tool for the study of realistic origami structures.

Von Hippel-Lindau disease: a single gene, several hereditary tumors

The Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by the predisposition for multiple tumors caused by germline mutations in the tumor suppressor gene VHL. This disease is associated with a high morbidity and mortality and presents a variable expression, with different phenotypes from family to family, affecting different organs during the lifetime. The main manifestations of VHL are hemangioblastomas of the central nervous system and retina, renal carcinomas and cysts, bilateral pheochromocytomas, cystic and solid tumors of the pancreas, cystadenomas of the epididymis, and endolymphatic sac tumors. The discovery of any of the syndrome components should raise suspicion of this disease and other stigmas must then be investigated. Due to the complexities associated with management of the various VHL manifestation, the diagnosis and the follow-up of this syndrome is a challenge in the clinical practice and a multidisciplinary approach is needed. The particular relevance to endocrinologists is the detection of pheochromocytomas in 35% and islet cell tumors in 17% of VHL patients, which can be associated with hypertension, hypoglycemia, cardiac arrhythmias, and carcinoid syndrome. The purpose of this review is to define the Von Hippel-Lindau syndrome addressing its clinical aspects and classification, the importance of genetic counseling and to propose a protocol for clinical follow-up.

Programmed buckling by controlled lateral swelling in a thin elastic sheet

Recent experiments have imposed controlled swelling patterns on thin polymer films, which subsequently buckle into three-dimensional shapes. We develop a solution to the design problem suggested by such systems, namely, if and how one can generate particular three-dimensional shapes from thin elastic sheets by mere imposition of a two-dimensional pattern of locally isotropic growth. Not every shape is possible. Several types of obstruction can arise, some of which depend on the sheet thickness. We provide some examples using the axisymmetric form of the problem, which is analytically tractable.

Application of factorial design to study of heavy metals biosorption by waste biomass from beverage distillery

A full factorial design leading to 20 sets of sorption runs was conducted to study the influence of four variables (bleaching earth and biomass concentrations, pH, and sorption time) on the iron, nickel, and chromium removal from stainless steel effluent using waste biomass from a beverage industry. Similar factor effects and interactions were found for each metal involved in this biosorption study, and the main factors were pH (positive effect) and biomass concentration (negative effect). Response surface methodology was adopted and an empirical linear polynomial model constructed on the basis of the specific uptake (mg of metal/g of biomass as dryweight) for each metal species. Under optimized process conditions (pH 4.0, biomass concentration of 2.0 g/L, absence of Celite), uptake values of 155 mg of Fe/g, 38 mg of Cr/g, and 0.4 mg of Ni/g were achieved after 3 h. This corresponded to a reduction in heavy metals concentration of approx 94% for Cr, 57% for Fe, and 25% for Ni.

Removal of heavy metals by an Aspergillus terreus strain immobilized in a polyurethane matrix

AIMS

The aim was to investigate the biosorption of chromium, nickel and iron from metallurgical effluents, produced by a steel foundry, using a strain of Aspergillus terreus immobilized in polyurethane foam.

METHODS AND RESULTS

A. terreus UFMG-F01 was immobilized in polyurethane foam and subjected to biosorption tests with metallurgical effluents. Maximal metal uptake values of 164.5 mg g(-1) iron, 96.5 mg g(-1) chromium and 19.6 mg g(-1) nickel were attained in a culture medium containing 100% of effluent stream supplemented with 1% of glucose, after 6 d of incubation.

CONCLUSIONS

Microbial populations in metal-polluted environments include fungi that have adapted to otherwise toxic concentrations of heavy metals and have become metal resistant. In this work, a strain of A. terreus was successfully used as a metal biosorbent for the treatment of metallurgical effluents.

SIGNIFICANCE AND IMPACT OF THE STUDY

A. terreus UFMG-F01 was shown to have good biosorption properties with respect to heavy metals. The low cost and simplicity of this technique make its use ideal for the treatment of effluents from steel foundries.

[Analysis of infant mortality in coverage areas of health centers in Belo Horizonte, Minas Gerais, Brazil (1994-1996)]

Geographic analysis of health conditions highlights regional and intra-urban inequalities. This study aims to identify intra-urban discrepancies in the city of Belo Horizonte, studying the infant mortality coefficients (IMC) in the various areas of the metropolitan area and evaluating their evolution from 1994 to 1996. The study uses data from 1994 to 1996 regarding birth and death records (from the SINASC and SIM registries). It also uses "thematic maps" related to geographic coverage areas of municipal health centers to demonstrate differences in infant mortality coefficients. The empirical Bayesian method was applied to correct possible random fluctuation in IMC due to small and unstable numbers. A 24.4% reduction in the overall coefficient was observed in the city from 1994 to 1996. Decreases also occurred in the health center coverage areas. In 1994, eight areas presented an IMC above 50/1,000, while in 1996 no area reached that coefficient. In 1994, 29 areas presented an IMC from 35 to 50/1,000, as compared to only four areas in 1996. In 1996 there were more areas with IMC below 35/1,000 as compared to 1994. In 1996, more homogeneity was observed in IMC distribution and hence a reduction in intra-urban inequalities.

Mouse B-1 cell-derived mononuclear phagocyte, a novel cellular component of acute non-specific inflammatory exudate

At least three B cell subsets, B-1a, B-1b and B-2, or conventional B cells are present in the mouse periphery. Here we demonstrate that B-1 cells spontaneously proliferate in stationary cultures of normal adherent mouse peritoneal cells. B-1 cells were characterized by morphology, immunohistochemistry and flow cytometry. IgM was detected in the supernatants of these cultures. We demonstrated that the major cell population analyzed expresses the B-1b phenotype. When these cells were transferred to a new culture, a large proportion of them adhere to the plastic surface, and spread as bipolar cells endowed with the capacity to phagocytose via Fc and mannose receptors. Flow cytometry analysis of these adherent cells demonstrated that the great majority of them share both B-220 and Mac-1 antigens. Nevertheless, 45% of them were exclusively Mac-1(+). Finally, when they were labeled in vitro with [(3)H]thymidine and transferred to the peritoneal cavity of naive mice, they migrate to a non-specific inflammatory focus induced by a foreign-body implant. These data demonstrate that B-1 cells, mainly B-1b cells, not only proliferate and differentiate into a mononuclear phagocyte in vitro, but also that they exit the peritoneal cavity and migrate to a non-specific inflammatory milieu.

Hypocellular anaplastic large cell lymphoma mimicking inflammatory lesions of lymph nodes

The subgroup of T/null-cell primary systemic anaplastic large cell lymphoma that expresses anaplastic lymphoma kinase (ALK) constitutes a distinctive clinicopathologic entity that exhibits a broad morphologic spectrum. The examples predominated by small cells or showing a mixed cell population can be difficult to recognize as being neoplastic. We report four such cases with a remarkably hypocellular granulation tissue-like appearance, mimicking an inflammatory or reparative process. All patients were young and presented with lymphadenopathy in multiple sites. The lymph node biopsies showed a hypocellular appearance, with wide separation of the small to medium-sized lymphoid cells by edematous or fibromyxoid stroma. There were interspersed spindly neoplastic cells resembling myofibroblasts, sometimes forming short, sweeping fascicles, as well as histiocytes. Occasional large cells with atypical nuclei were identified. The larger lymphoid cells tended to form cuffs around the venules. In two cases, the capsule and fibrous trabeculae were markedly broadened with increased spindly cells, mimicking inflammatory pseudotumor of lymph node. Immunostaining showed dispersed and clustered CD30+ ALK+ cells, confirming a diagnosis of anaplastic large cell lymphoma. In conclusion, a diagnosis of hypocellular anaplastic large cell lymphoma requires a high index of suspicion. The young age of the patients and the presence of perivascular cuffs of larger lymphoid cells should provide the strongest clues to the correct diagnosis.

Mechanisms mediating substance P-induced contraction in the rat iris in vitro

PURPOSE

To determine some of the mechanisms by which substance P (SP) induces contraction in the isolated rat iris.

METHODS

Rings of rat iris were mounted in a 5-ml organ chamber containing Krebs solution at 37 degrees C under basal tension of 75 mg, and isometric tension was recorded.

RESULTS

Substance P produced graded contraction in the rat iris, being approximately 40-fold more potent than carbachol. Peptidase inhibitors (captopril, phosphoramidon, thiorphan) did not affect the SP response. The SP contraction was dependent on external Ca2+ by a mechanism resistant to both nifedipine and omega-conotoxin GVIA. Atropine and tetrodotoxin significantly shifted the SP response to the right (three- and fivefold, respectively). Neither phorbol nor genistein altered the SP-induced contraction, whereas staurosporine caused a weak inhibition. Indomethacin, pyrilamine, guanethidine, 8-37 calcitonin gene-related peptide (CGRP) fragment, and NG-nitro-L-arginine methyl ester had no effect on SP response. All the natural tachykinin agonists caused concentration-dependent contraction in rat iris with similar maximal responses. The NK3 selective agonist senktide caused graded contraction, being approximately 150-fold more active than the NK2 selective agonist [beta-ala] NKA. The NK1 selective agonist SP methyl ester induced a small contraction. The NK3 and NK2 antagonists SR 142801 and SR 48968 shifted the SP response to the right. Schilds plots gave pA2 (negative logarithm of the molar concentration of antagonist causing a twofold rightward displacement of the concentration response curves) values of 9.37 and 7.97 and slopes of 0.70 and 1.02, respectively.

CONCLUSIONS

Substance P produces a potent contraction in the isolated rat iris that seems to depend on the neural release of acetylcholine by tetrodotoxin-sensitive mechanisms. Its response relies largely on external Ca2+, through mechanisms independent of activation of L- or N-type Ca2+ channels, and is probably mediated via activation of NK3 and NK2 receptors.

Subcutaneous infection of mice with Paracoccidiodes brasiliensis induces a peculiar pattern of inflammatory and immune responses

It is well established that resistance or susceptibility to Paracoccidioidis brasiliensis infection in mice is under strict host's genetic control. Mice from A/Sn strain inoculated by the ip route are resistant to fungal infection while infection induced in mice from B10.A strain results in a fatal disease. The early cellular events of infection in both strains are characterized by a marked neutrophilic infiltration that is more prominent in B10.A mice. A peculiar characteristic of the Paracoccidioides brasiliensis-mouse model is that the subcutaneous (sc) inoculations of the fungus either in resistant (A/Sn) or susceptible (B10.A) mice is self-curing and tums mice from the B10.A strain able to express typical DTH reaction to fungal antigens, as observed in A/Sn mice. Here we report the investigation on the early events of the inflammatory response induced by the inoculation of live fungus into the hind footpad of A/Sn (resistant) and B10.A (susceptible) mice. The influence of neutrophils on the inflammatory response and antibody titers or DTH response to gp43, the major fungal antigen, was also evaluated. Results showed a different course of the inflammatory response induced by fungal inoculation in A/Sn and B10.A mice. Neutrophil depletion before infection differently influenced the kinetics of the inflammatory process in both mice strains but did not modify the fungal load in the lesions. In neutrophil depleted mice from both strains, a decrease in DTH response and an increase in total antibody titers to gp43 were observed. The significant increase in the fungal load in lesions seen in nude mice indicates that the self-limited infection evoked by fungal inoculation into the subcutaneous tissue is a T-cell dependent phenomenon. The implications of these observations in the pathogenesis of paracoccidioidomycosis are discussed.

Characterization of the mechanism involved in the relaxant response of dopexamine in the guinea pig pulmonary artery in vitro

Dopexamine is a synthetic catecholamine used for the management of low-cardiac-output states. The purpose of this study was to characterize some of the mechanisms underlying dopexamine-mediated relaxation in the guinea pig pulmonary artery (PA) in vitro. Dopexamine (EC50, 1.2 microM; Rmax, 100%), like dobutamine (EC50, 1.4 microM, Rmax, 93.3%), prostacyclin (PGI2; EC50, 37 nM; Rmax, 96.2%), sodium nitroprusside (EC50, 370 pM; Rmax, 96.9%), forskolin (EC50, 47 pM: Rmax, 98.6%), and SKF 38393 (EC50, 120 nM; Rmax, 100%), caused graded relaxation in rings of PA precontracted by phenylephrine. The dopexamine vasorelaxation was antagonized by propranolol (1 microM), SCH 23390 (100 nM, a D1-dopamine antagonist), sulpiride (1 microM), glibenclamide (30 microM), tetraethylammonium (3 mM), apamin (100 nM), charybdotoxin (100 nM), SQ 22536 (10 microM, an adenylyl cyclase inhibitor), KT 5720 (10 microM, a protein kinase A inhibitor) and by calcitonin gene-related peptide (CGRP) or vasoactive intestinal peptide (VIP)-receptor antagonists (both 100 nM), as well as by chymotrypsin (1 U/ml). Neither the prior incubation of N(G)-nitro-L-arginine (100 pM), indomethacin (1 microM), nor removal of the vascular endothelium interfered with dopexamine vasorelaxation response in PA. Thus dopexamine relaxation in PA is mediated by activation of beta-adrenoceptors and dopamine receptors, and by the opening of both low- and high-conductance Ca2+-activated K+ channels, partially through adenosine triphosphate (ATP)-sensitive K+ channels. In addition, dopexamine-induced relaxation in PA seems to involve the release of peptides such as VIP and CGRP, an effect mediated by a cyclic adenosine monophosphate (cAMP)-dependent mechanism.

Laparoscopic diagnosis and treatment of splenogonadal fusion associated with intra-abdominal cryptorchidism in a child

The authors describe the surgical findings and laparoscopic treatment in a child with splenogonadal fusion associated with intra-abdominal cryptorchidism. Laparoscopy was shown to be an excellent method for the diagnosis and treatment of this condition. No reports of similar cases using the technique were found in the literature.

Antinociceptive effect of the calcium-binding protein MRP-14 and the role played by neutrophils on the control of inflammatory pain

Macrophages secrete a variety of chemical mediators that play a central role in the pathophysiology of inflammatory pain. Therefore, the activation or deactivation of these cells in an inflammatory focus could modulate the intensity of the algogenic response. Based on these premises and on our previous demonstration that the calcium-binding protein MRP-14, highly expressed in neutrophils, deactivates activated macrophages in vitro, we decided to investigate the role of MRP-14 and of neutrophils in the control of inflammatory pain in mice. Our results show that this protein is endowed with antinociceptive activity. When tested in the writhing model it was able to inhibit pain response but did not change the behavior of the animals in the hot plate test. This observation indicates that MRP-14 down-regulates inflammatory but not central pain. Using a model of acute neutrophilic peritonitis induced by glycogen, a close correlation between neutrophil migration and antinociception was detected. Surgical adrenalectomy demonstrated that the antinociceptive response induced by glycogen was not due to endogenous liberation of glucocorticoids. The treatment of animals either with a monoclonal antibody anti-MRP-14 or a monoclonal antibody that depletes the animals of neutrophils reverts the antinociceptive response observed in the glycogen-induced peritonitis. These data define the calcium-binding protein MRP-14 as a novel mediator for the control of inflammatory pain and consequently discloses an anti-inflammatory role for the neutrophil.

Analysis of the mechanisms underlying the contractile response induced by the hydroalcoholic extract of Phyllanthus urinaria in the guinea-pig urinary bladder in-vitro

The hydroalcoholic extract of Phyllanthus urinaria (Euphorbiaceae), substance P and substance P methyl ester all caused graded contractions in the guinea-pig urinary bladder. Responses to hydroalcoholic extract and substance P were markedly inhibited in calcium-free Krebs solution, this effect being reversed by reintroduction of calcium in the medium. The contraction in response to hydroalcoholic extract was unaffected by atropine, propranolol, prazosin, yohimbine, tetrodotoxin, w-conotoxin, nicardipine, HOE 140, guanethidine, staurosporine, phorbol ester or indomethacin, excluding the involvement of nervous mediated responses, or action via cholinergic, adrenergic, kinins, cyclo-oxygenase metabolites, protein kinase C or activation of L or N-type calcium channels. The selective NK1 tachykinin antagonist (FK 888), but not NK2 (SR 48968) antagonized substance P-induced contraction, but both drugs failed to effect Phyllanthus urinaria-induced contraction. Prolonged desensitization of guinea pig urinary bladder with capsaicin (10 microM) or preincubation of guinea-pig urinary bladder with capsazepine did not affect contraction caused by hydroalcoholic extract. Ruthenium red almost completely abolished capsaicin-induced contraction, but had no effect on hydroalcoholic extract-mediated contraction. Substance P and the hydroalcoholic extract caused marked potentiation of the twitch response in the preparations field stimulated. The facilitatory effect of substance P, but not that of hydroalcoholic extract, was prevented by the NK1 (FK 888), but not by NK2 (SR 48968) antagonist. We concluded that contraction induced by hydroalcoholic extract of Phyllanthus urinaria in the guinea pig urinary bladder involves direct action on smooth muscle and relies on the mobilization of extracellular calcium influx unrelated to activation of L- and N-type calcium channels or activation of protein kinase C mechanisms. In addition contraction caused by the hydroalcoholic extract of Phyllanthus urinaria in guinea-pig urinary bladder does not involve the activation of tachykinin or vanilloid receptors.

[Gastric liposarcoma: report of a case]

The authors present a case of a well differentiated gastric liposarcoma. The tumor was situated in the submucosa of the antrum, had a diameter of 9 cm, and showed well defined borders. A subtotal gastrectomy with BI reconstruction was performed. No abdominal metastases were observed. The patient is in good condition, without recurrence of the tumor 19 months after its removal.

[The satisfaction of the clients of an outpatient consultation in view of the nursing team's approach]

The present research work about "the satisfaction of the clients of an out-patient department toward the approach of the nursing team" was carried out in a central hospital, in Lisbon, with a sample of 82 clients. The principal subjects broached on the biliography revision are: some risk factors of cardiovascular disease and the client approach. We have found at the end of this study that the precordial pain, the arrhythmias and the arterial hypertension, are the main causes that alert the clients, as well as the health professionals who send them to this department to a precocious diagnosis of cardiovascular disease. It was applied an approach guide to the clients of the experimental group and another instrument, a formulary was applied to both of the groups. The mean and the mode were used as measures of central tendency on the statistical treatment and as measures of dispersion the standard deviation and the variation amplitude. For testing our hypothesis we used the following tests: Kolmogoro-Sairnov, Qui-Square with the Coefficient of Yule and the Difference of Means Test, to a significance level of 0.05. All these tests confirmed our hypothesis, meaning that the clients to whom the new nurse-client-approach has been applied showed greater satisfaction than those who have been approached according to the usual procedure on the department and the majority of these clients suggest the continuation of this kind of approach.

Cytosine arabinoside induced gastrointestinal toxic alterations in sequential chemotherapeutic protocols: a clinical-pathologic study of 33 patients

Sequential chemotherapeutic regimens, primarily used in the treatment of hematopoietic malignancies, and employing ara-C as a basic antineoplastic agent induce mucosal alterations in the entire gastrointestinal tract. These are characterized by surface and glandular epithelial atypia, immaturity, and necrosis. Glandular regeneration is characteristically delayed leading to a state of intestinal aproliferative cytopenia. Other toxic intestinal changes include telangiectasia of blood vessels and the formation of intramural hematomas. Intestinal infections develop frequently and are complicated by peritonitis, liver abscesses, pneumatosis cystoides in testinalis and sepsis. These intestinal lesions are accompanied by a predictable clinical syndrome which begins concomitantly with ara-C infusions and is characterized by diarrhea, ileus, abdominal pain, hematemesis and melena, severe hypokalemia, hypocalcemia and a protein-losing enteropathy. Additional toxic manifestations induced by ara-C include transient weight gains, fever elevations and severe bone marrow depression. The genesis of the intestinal lesions is linked to the three day dose schedule of ara-C infusions which insures both arrest of the cycling intestinal cells in the S-phase and a high cytotoxic index. The severity of these lesions is markedly augmented by prior treatment with ara-C and cyclophosphamide which causes synchronization and probable recruitment of intestinal stem cells, respectively.

Cytosine arabinoside induced gastrointestinal toxic alterations in sequential chemotherapeutic protocols: a clinical-pathologic study of 33 patients

Sequential chemotherapeutic regimens, primarily used in the treatment of hematopoietic malignancies, and employing ara-C as a basic antineoplastic agent induce mucosal alterations in the entire gastrointestinal tract. These are characterized by surface and glandular epithelial atypia, immaturity, and necrosis. Glandular regeneration is characteristically delayed leading to a state of intestinal aproliferative cytopenia. Other toxic intestinal changes include telangiectasia of blood vessels and the formation of intramural hematomas. Intestinal infections develop frequently and are complicated by peritonitis, liver abscesses, pneumatosis cystoides in testinalis and sepsis. These intestinal lesions are accompanied by a predictable clinical syndrome which begins concomitantly with ara-C infusions and is characterized by diarrhea, ileus, abdominal pain, hematemesis and melena, severe hypokalemia, hypocalcemia and a protein-losing enteropathy. Additional toxic manifestations induced by ara-C include transient weight gains, fever elevations and severe bone marrow depression. The genesis of the intestinal lesions is linked to the three day dose schedule of ara-C infusions which insures both arrest of the cycling intestinal cells in the S-phase and a high cytotoxic index. The severity of these lesions is markedly augmented by prior treatment with ara-C and cyclophosphamide which causes synchronization and probable recruitment of intestinal stem cells, respectively.

Cytosine arabinoside induced gastrointestinal toxic alterations in sequential chemotherapeutic protocols: a clinical-pathologic study of 33 patients

Sequential chemotherapeutic regimens, primarily used in the treatment of hematopoietic malignancies, and employing ara-C as a basic antineoplastic agent induce mucosal alterations in the entire gastrointestinal tract. These are characterized by surface and glandular epithelial atypia, immaturity, and necrosis. Glandular regeneration is characteristically delayed leading to a state of intestinal aproliferative cytopenia. Other toxic intestinal changes include telangiectasia of blood vessels and the formation of intramural hematomas. Intestinal infections develop frequently and are complicated by peritonitis, liver abscesses, pneumatosis cystoides in testinalis and sepsis. These intestinal lesions are accompanied by a predictable clinical syndrome which begins concomitantly with ara-C infusions and is characterized by diarrhea, ileus, abdominal pain, hematemesis and melena, severe hypokalemia, hypocalcemia and a protein-losing enteropathy. Additional toxic manifestations induced by ara-C include transient weight gains, fever elevations and severe bone marrow depression. The genesis of the intestinal lesions is linked to the three day dose schedule of ara-C infusions which insures both arrest of the cycling intestinal cells in the S-phase and a high cytotoxic index. The severity of these lesions is markedly augmented by prior treatment with ara-C and cyclophosphamide which causes synchronization and probable recruitment of intestinal stem cells, respectively.