Pitcairniaabscondita (Pitcairnioideae, Bromeliaceae), a hidden novelty from north-western Jalisco, Mexico.

Pitcairniaabscondita sp. nov., known until now only from the Municipalities of Cabo Corrientes, Mascota, Puerto Vallarta, San Sebastián del Oeste and Talpa de Allende in the State of Jalisco, Mexico, is here described and illustrated. The new taxon was confused with P.imbricata for long time, but differs from this species by its green floral bracts with the apex divergent to spreading (vs. red and appressed) and by the appendiculate at the base chartreuse-green petals (vs. not appendiculate yellow petals). Images and a distribution map of the taxa are presented.

ResumenSe describe e ilustra Pitcairniaabscondita sp. nov., conocida hasta ahora únicamente de los municipios de Cabo Corrientes, Mascota, Puerto Vallarta, San Sebastián del Oeste y Talpa de Allende, en el estado de Jalisco, México. El nuevo taxon fue por largo tiempo confundido con P.imbricata, pero difiere de la misma por sus brácteas florales verdes con el ápice divergente a extendido (vs. brácteas rojas y adpresas) y por sus pétalos verdes chartreuse con apéndices en la base (vs. pétalos amarillos sin apéndices en la base). Se incluyen imágenes y un mapa de distribución de las especies.

Aesthetics and the perceived stigma of assistive technology for visual impairment.

PURPOSE: The aim of this study was to identify factors that influence the perceived stigma of two assistive devices for visual impairment, namely the white cane and smart glasses. METHOD: Face-to-face semi-structured interviews with eight European students were conducted to probe their experiences and knowledge related to disability, assistive technology, visual impairment, as well as handheld and wearable devices. RESULTS: Close relationships with disabled people seems to have a positive influence on participants perceptions about stigma, disability, and assistive technology. Academic background seems to not have any influence. The aesthetics of assistive devices was observed as an important factor that influences the adoption or abandonment of the device. CONCLUSION: Device without negative symbolism but with modern aesthetics (smart glasses) were positively accepted by the participants than the device with traditional aesthetics and symbolisms of visual impairment (white cane). Designers should, therefore, consider aesthetics in addition to functionality in order to avoid the perceived stigma, thereby reducing the chances of device abandonment.IMPLICATIONS FOR REHABILITATIONUnderstanding the factors that influence the perceived stigma associated with assistive technology can help designers and developers to reduce assistive technology abandonment and perceived stigma.Designers need to consider both functionality and aesthetics. While functionality is crucial for the users' adaptation, aesthetics is important for the users' positive perceptions.

Effects of acute arsenic exposure in two different populations of Hyalella curvispina amphipods from North Patagonia Argentina.

Arsenic (As) is a toxic metalloid present in high levels in diverse regions of Argentina. The aim of this study was to determine acute As-mediated toxicity in two different populations of autochthonous Hyalella curvispina amphipods from a reference site (LB) and an agricultural one (FO) within North Patagonia Argentina. Previously, both populations exhibited significant differences in pesticide susceptibility. Lab assays were performed to determine acute lethal concentrations, as well as some biochemical parameters. Lethal concentration (LC50) values obtained after 48 and 96 hr As exposure were not significantly different between these populations, although FO amphipods appeared slightly less susceptible. LC50-48 hr values were 3.33 and 3.92 mg/L As, while LC50-96 hr values were 1.76 and 2.14 mg/L As for LB and FO amphipods. The no observed effect concentration (NOEC) values were 0.5 mg/L As. Cholinesterase (ChE) activity was significantly diminished by As acute exposure (0.5-1.5 mg/L As), indicative of a significant neurotoxic action for this metalloid in both amphipod populations. Activities of catalase (CAT) and glutathione S-transferase (GST) and levels of reduced glutathione (GSH) were differentially altered following As exposure. CAT activity was increased after 96 hr As exposure. GST activity and GSH levels were significantly elevated followed by either a decrease or a return to control values after 96 hr treatment. However, additional studies are necessary to understand the mechanisms underlying the As-mediated oxidative effects in H. curvispina. Our findings suggest that measurement of ChE activity in H. curvispina amphipods might serve as a useful biomarker of As exposure and effect.

Gestational and Breastfeeding Low-Protein Intake on Blood Pressure, Kidney Structure, and Renal Function in Male Rat Offspring in Adulthood.

Background: Our previous studies demonstrated that maternal protein-restricted (low-protein, LP) 16-week-old offspring had pronounced nephron number reduction and arterial hypertension associated with an unchanged glomerular filtration rate (GFR). An enhanced gomerular area may be related to increased glomerular filtration and overflow, which accounts for glomerular filtration barrier breakdown and early glomerulosclerosis. The effect of protein restriction during gestational and breastfeeding periods is unknown. Method: The functional e-structural kidney evaluation was obtained using lithium and creatinine clearance, kidney morphometry, immunoblotting, and immunostaining analysis in 16 and 24-week-old LP offspring compared to age-matched NP progeny. Results: Low protein rats' progeny had significantly reduced birth weight, without previous catch-up growth phenomena, in parallel with a decreased adiposity index. Transforming growth factor-beta 1 (TGF-ß1) glomerular expression was significantly enhanced in the LP group. Also, the LP offspring had a 38% lower nephron number and an increased glomerular volume. They also presented with a higher cardiac index and arterial blood pressure compared with age-matched NP offspring. The LP rats exhibited augmented Na+/K+-ATPase in the proximal segments, and NOS1 immunoreactivity in whole renal tissue was associated with sodium retention in the proximal nephron segments. We also found significantly enhanced collagen content associated with increased TGFß1 and ZEB1/2 renal immunoreactivity in LP offspring compared with NP offspring. Increased hypertrophy markers in LP podocytes were associated with an amplified IL-6/STAT3 pathway activity. Conclusion: To our knowledge, these are the first data demonstrating renal functional and structural changes in protein restriction during gestation and lactation model of fetal programming. The fetal-programmed adult offspring showed pronounced structural glomerular disorders with an accentuated and advanced fibrosis stage, without a change in the GFR. These findings suggest that the glomerular enhanced TGF-ß1 action may induce ZEB1/2 expression that may cause glomeruli epithelial-to-mesenchymal transition. Besides, decreased nephron number in the LP offspring with preserved glomerular function may be related to protective or even attenuate the activated IL-6/STAT3 pathway.

Pehuén (Araucaria araucana) seed residues are a valuable source of natural antioxidants with nutraceutical, chemoprotective and metal corrosion-inhibiting properties.

In the last decade, green chemistry has been attracting great interest in many contexts, including, among others, natural antioxidants. However, only a few works deal with natural residue extracts and biowaste, which could be an efficient, economical and environmentally friendly source for the production of useful compounds. In this study, we look for antioxidant activity in Araucaria araucana seeds, an iconic pine species of the Argentine and Chilean Patagonia commonly known as "pehuén". Piñones are the edible pehuén seeds, and it is estimated that approximately 40 tons of piñones are harvested annually in Argentina and Chile. The chemical composition, antioxidants, metal corrosion-inhibiting properties and biological activity of edible and discarded piñón tissues were determined. Acute toxicity was discarded by in vitro testing and double fluorescent staining. Biological activity was evaluated in vivo by determining redox markers in salivary glands from rats treated with Cyclophosphamide (an oncological drug). All piñón tissues had antioxidants and antioxidant activity, with the coats showing the highest levels (up to 404 µg ascorbic acid equivalent per mg). The coats, in particular, had high gallic acid, catechin, quercetin and tannin contents, and more antioxidant activity, polyphenols and flavonoids than berries from the region. Results by X-ray fluorescence spectrometry showed that Na, Mg, P, S, Cl, K, and Ca were majority elements in the coat, embryo and endosperm. Furthermore, coat extract also showed significant anti-corrosion activity and in vivo protection against oxidative damage. The results indicate that piñón biowaste is a low-cost attractive source of natural antioxidants with potential nutraceutical, medical and metal corrosion protection applications.

Degradation of metformin in water by TiO2-ZrO2 photocatalysis.

The increasing use of pharmaceutical products also increases their release in aquatic environment. These contaminants are considered emerging pollutants, and induce adverse ecological and human health effects. The antidiabetic metformin is one example that has been detected in the aquatic environment at unusual concentrations. This fact indicates that conventional wastewater treatment is inefficient on eliminating this compound. Here we show that metformin can be effectively removed from water by photocatalysis. We found the optimised conditions for pH and concentration of catalyst on the photocatalytic process. TiO2 and TiO2-ZrO2 were successful in oxidising metformin under UV radiation following a pseudo-first order kinetics. Intermediates of metformin photodegradation appeared after photocatalytic treatment. Toxicity analysis showed that the degradation products are non-toxic to Lactuca sativa seeds.

Novelties in the genus Viridantha Espejo (Tillandsioideae, Bromeliaceae).

Based on morphological evidence, we propose to raise Tillandsia mauryana forma secundifolia to species level with the name Viridantha secundifolia (Ehlers) Hern.-Cárdenas, Espejo & López-Ferr. Viridantha secundifolia can be readily distinguished by the falciform rosettes, the broadly oblong to square, 1-1.2 × 0.8-1.1 cm leaf sheaths and by the 1.8-2 × 0.7-1.2 cm floral bracts. Additionally, we describe and illustrate Viridantha uniflora Hern.-Cárdenas, Espejo & López-Ferr., from the state of Oaxaca, Mexico. The new species is morphologically similar to Viridantha boqueronensis, but differs by the nearly square leaf sheaths, 1.3-1.5 × 0.4-0.5 cm spikes and by the presence of only one flower per spike. A key to the taxa, morphological descriptions, list of specimens examined, illustrations and a distribution map of the described taxa are included.

ResumenCon base en evidencia morfológica, proponemos elevar a nivel de especie a Tillandsia mauryana forma secundifolia con el nombre Viridantha secundifolia (Ehlers) Hern.-Cárdenas, Espejo & López-Ferr. Viridantha secundifolia puede distinguirse fácilmente por las rosetas falciformes, las vainas foliares ampliamente oblongas a cuadradas, de 1­1.2 × 0.8­1.1 cm y por las brácteas florales de 1.8­2 × 0.7­1.2 cm. Además, se describe e ilustra Viridantha uniflora Hern.-Cárdenas, Espejo & López-Ferr., del estado de Oaxaca, México. La nueva especie es morfológicamente similar a Viridantha boqueronensis pero difiere por las vainas foliares cuadradas, la espigas de 1.3­1.5 × 0.4­0.5 cm y por presentar una sola flor por espiga. Se proporciona una clave de identificación, descripciones morfológicas, lista de ejemplares examinados, ilustraciones y un mapa de distribución de los taxa descritos.

Distribución geográfica de angiospermas epífitas de la región terrestre prioritaria Cerros Negro-Yucaño, Oaxaca, México / Geographical distribution of epiphytic angiosperms of the priority terrestrial region of Cerros Negro-Yucaño, Oaxaca, Mexico

Resumen El conocimiento sobre la riqueza y la distribución de las plantas epifítas vasculares es aún incompleto en muchas áreas de México. Un ejemplo es la región terrestre prioritaria (RTP) Cerros Negro-Yucaño, que se ubica en el noroeste del estado de Oaxaca y pertenece a la región mixteca alta (Ñuu Savi Sukun, Ñuu vixi). Con base en la revisión de material de herbario en 12 colecciones institucionales mexicanas y en la recolección de especímenes en algunas localidades, principalmente cubiertas por bosque de encino, en 17 de los 18 municipios que incluye la RTP, se compilo un listado de las angiospermas epífitas. Se registró la presencia de 40 especies, distribuidas en 13 géneros y cinco familias; 28 taxa son endémicos de México y tres de ellos se conocen solamente de Oaxaca. Los géneros Tillandsia (18 spp.) y Peperomia (4) fueron los mejor representados en el área. El bosque de encino fue el tipo de vegetación en el cual se encontraron más epífitas (32 spp.) y también el intervalo altitudinal de 1 900 a 2 100 m (19 spp.). Plantas en floración de Artorima erubescens, Laelia albida, L. furfuracea y Prosthechea karwinskii, son utilizadas por pobladores de la región como ornamentales, durante las celebraciones religiosas de Día de Muertos y Semana Santa. Este impacto humano podría representar una amenaza para las poblaciones silvestres de estas especies en el futuro.(AU)

Abstract The knowledge on richness and distribution of epiphytic vascular plants is still incomplete in many areas of Mexico. An example is the terrestrial priority region (RTP) Cerros Negro-Yucaño, which is located in the Northwest portion of Oaxaca and belongs to the Mixteca Alta Region (Ñuu Savi Sukun, Ñuu Vixi). Based on herbarium material revision of 12 Mexican institutional collections and the collection of specimens in some localities, mainly covered by oak forest, in 17 of the 18 municipalities included in the RTP, we compiled a list of epiphytic angiosperms. The presence of 40 species, distributed in 13 genera and five families was recorded; 28 taxa are endemic to Mexico and three of them are only known from Oaxaca. The genera Tillandsia (18 spp.) and Peperomia (4) were the best represented genera in the area. Oak forest was the type of vegetation in which the most of the epiphytes were found (32 spp.), and also the altitudinal range between 1 900 and 2 100 m (19 spp.). Flowering plants of Artorima erubescens, Laelia albida, L. furfuracea, and Prosthechea karwinskii are used by the local people as ornamentals during the religious celebrations of Day of the Dead (Mexico) and Holly Week. This human impact might be a threat to the wild populations of these species in the future.(AU)

Strategies for Developing Students' Empathy and Awareness for the Needs of People with Disabilities: Contributions to Design Education.

The design of products for people with disabilities requires the understanding of a wide range of factors related to users' health, functional abilities, needs, expectations and preferences. Such multifactorial perspective is often perceived as beyond the reach by the students of both graphic and product design, as it comprises knowledge from different areas such are not usually part of design curriculum as health, rehabilitation, computer science and biomedical engineering. Here, we report on strategies for developing design students' empathy and awareness for the needs and expectations of people with disabilities. By means of a combination of theoretical and practical approaches, a course on Inclusive Design was developed as part of the regular curriculum of the Bachelor Programme in Design at Sao Paulo State University (UNESP, Bauru campus, Brazil), with the collaborative participation of members of SORRI BAURU Rehabilitation Center. The final projects developed by the students were based on the demands presented by SORRI BAURU's rehabilitation team, and results reveal that the theoretical-practical approach based on interdisciplinarity was shown to provide the design students a learning experience that, ultimately, supports the quality decision-making in the design process. This paper describes the pedagogical approach, theoretical contents and practical activities developed during the Inclusive Design course. The challenges, benefits, results, and contributions of this experience from the perspective of the design education are also discussed.

Acute toxicity and esterase response to carbaryl exposure in two different populations of amphipods Hyalella curvispina.

During the last years, a carbaryl insecticide was extensively applied in the valley of Río Negro and Neuquén, North Patagonia Argentina, to manage codling moths (Cydia pomonella), the main pest of pear and apple trees. In this study carbaryl susceptibility and B-esterase activity from both insecticide-exposed and non-exposed field populations of amphipods Hyalella curvispina were studied. Two subpopulations, one susceptible to carbaryl (LC50=213±7.5µg/L carbaryl) and one resistant to it (LC50=14,663±2379µg/L carbaryl), were found in the agricultural area selected in this study. Both populations were, in turn, more resistant to carbaryl than the population from a pristine area (LC50=11.31±2.27µg/L carbaryl). The in vivo 48h-IC50 values for cholinesterase (ChE) were close to the corresponding 48h-LC50 values as determined for the non-exposed population (IC50=7.16±0.86µg/L carbaryl) and for the susceptible subpopulation from the insecticide-exposed site (IC50=193±99µg/L carbaryl). Carbaryl exposure of the amphipods from the agricultural area mentioned above produced a significant decrease of carboxylesterase (CabE) activity, at a sublethal concentration (10µg/L) that was not able to significantly inhibit ChE, thereby showing a protective role of CabE and its usefulness as early biomarker. However, at lethal concentrations the inhibition of ChE activity was higher than that of CabE. On the other hand, CabE of amphipods from the pristine site was less sensitive to carbaryl than ChE, suggesting a different participation of CabE in ChE protection in the susceptible population of H. curvispina. Pulse exposure to carbaryl for 2h caused a significant inhibition of ChE in amphipods from both populations, with a fast recovery as expected for a carbamate insecticide. In conclusion, we proved that amphipods from the said agricultural area have developed resistance to carbaryl and showed the presence of two subpopulations with a different response to the insecticide. Moreover, these results reinforce the use of ChE together with CabE inhibition as indicators of carbamate exposure in H. curvispina.

Low-Density Lipoprotein Cholesterol Is Associated With Asymptomatic Sensorineural Hearing Loss in Patients With Systemic Lupus Erythematosus.

OBJECTIVE: The aims of this study were to determine the frequency of asymptomatic sensorineural hearing loss (SNHL) in systemic lupus erythematosus (SLE) and to determine the association between SNHL and demographic, clinical, and laboratory features and cardiovascular risk factors. METHODS: We conducted a cross-sectional study including consecutive female SLE patients. We performed audiometry and clinical and laboratory evaluation and determined cardiovascular risk factors in all patients. Statistical analysis included principal component analysis and logistic regression. RESULTS: Eighty-nine women were included with mean age of 38.98 (SD, 7.77) years and mean disease duration of 10.29 (SD, 9.19) years. Asymptomatic SNHL was observed in 14 patients (16%). In logistic regression model, only low-density lipoprotein levels (z = 2.64; P = 0.008) were associated with SNHL. CONCLUSIONS: We observed asymptomatic SNHL in 16% of SLE and an association with low-density lipoprotein levels suggesting atherosclerosis as a mechanism. Follow-up is needed to determine clinical implications.

Factors related to blood pressure control in a prospective cohort of hypertensive outpatients / Fatores relacionados ao controle da pressão arterial em coorte prospectiva de pacientes hipertensos ambulatoriais

Previous studies have reported a controversial relationship between inadequate blood pressure control and predictor variables. Current prospective cohort study analyzes the interference of age, gender, diabetes and medication adherence in the control of blood pressure of hypertensive outpatients. Patients were interviewed under blind conditions to determine medication adherence, and clinical variables assessment were standardized. Univariate analysis of variance identified the variables correlated to blood pressure control at the end of the follow-up period. Missing data were excluded from analysis. After adjusting for confounders with univariate analysis, the association between the outcome (BP control rate) with significant factors and the calculated adjusted odds ratios (OR) and their 95% CI was analyzed by logistic regression. No interference by age or medication adherence in blood pressure control was reported. In fact, the higher the number of medications in use, the greater were the chances of having blood pressure control in disorder. Females are associated with a 3.1 increase in odds ratio of poor blood pressure control. Compared with non-diabetic hypertensive patients, hypertensive diabetic ones had a lower chance of poor blood pressure control.

Estudos anteriores encontraram relações controversas entre o inadequado controle da pressão arterial e variáveis preditoras. Nesta coorte prospectiva, objetivamos analisar a interferência da idade, do gênero, da presença de diabetes e da adesão à medicação no controle da pressão arterial em pacientes hipertensos ambulatoriais. Os pacientes foram entrevistados sob condições de cegamento dos avaliadores na mensuração da adesão à medicação, e a metodologia de avaliação das variáveis clínicas foi padronizada. Uma análise univariada identificou quais variáveis correlacionaram-se com o controle da pressão arterial ao final do período de seguimento. Dados faltantes foram excluídos da análise. Após ajuste para variáveis de confusão por meio da análise univariada, analisamos as associações entre o desfecho (controle da pressão arterial) e variáveis preditoras, e calculamos o odds ratio ajustado e seu intervalo de confiança de 95%, utilizando regressão logística. Não encontramos interferência da idade ou aderência aos medicamentos no controle tensional. Constatamos que, quanto maior o número de medicamentos em uso, maiores as chances de apresentar controle tensional fora das metas. O gênero feminino associou-se com o aumento de 3,1 vezes na chance de mau controle da pressão arterial. Comparados com pacientes hipertensos não diabéticos, os hipertensos diabéticos tiveram menores chances de apresentar mau controle tensional.

Toxicity of the insecticide chlorpyrifos to the South American toad Rhinella arenarum at larval developmental stage.

Chlorpyrifos (CPF) is an insecticide widely used for pest control in the fruit-productive region of North Patagonia, Argentina, where it is found in superficial waters. The aim of this study was to establish the toxic effects of CPF in Rhinella arenarum toad larvae as a potentially exposed species. We determined the 96 h-LC50 (1.46 ± 0.27 mg/L), the LOEC (0.81 mg/L, LC10) and NOEC (0.43 mg/L, LC1) for CPF lethality as endpoint. We also analyzed biochemical biomarkers in larvae exposed to sublethal CPF concentrations. The IC50 for cholinesterase was 0.113 ± 0.026 mg/L, one order of magnitude lower than the LC50. Carboxylesterase activity was inhibited, buffering OP toxicity on cholinesterase. Reduced glutathione increased after 24h as an antioxidant response, and decreased at 96 h together with catalase activity, due to oxidative stress. These biochemical effects suggest that environmentally relevant CPF concentrations pose a threat to R. arenarum larvae progression.

Acute toxicity of arsenic and oxidative stress responses in the embryonic development of the common South American toad Rhinella arenarum.

Arsenic (As), a natural element of ecological relevance, is found in natural water sources throughout Argentina in concentrations between 0.01 mg/L and 15 mg/L. The autochthonous toad Rhinella arenarum was selected to study the acute toxicity of As and the biochemical responses elicited by the exposure to As in water during its embryonic development. The median lethal concentration (LC50) value averaged 24.3 mg/L As and remained constant along the embryonic development. However, As toxicity drastically decreased when embryos were exposed from heartbeat-stage on day 4 of development, suggesting the onset of detoxification mechanisms. Given the environmental concentrations of As in Argentina, there is a probability of exceeding lethal levels at 1% of sites. Arsenic at sublethal concentrations caused a significant decrease in the total antioxidant potential but generated an increase in endogenous glutathione (GSH) content and glutathione S-transferase (GST) activity. This protective response might prevent a deeper decline in the antioxidant system and further oxidative damage. Alternatively, it might be linked to As conjugation with GSH for its excretion. The authors conclude that toad embryos are more sensitive to As during early developmental stages and that relatively high concentrations of this toxic element are required to elicit mortality, but oxidative stress may be an adverse effect at sublethal concentrations.

Acute toxicity and biochemical effects of azinphos methyl in the amphipod Hyalella curvispina.

We evaluated the acute toxicity and biochemical effects of the organophosphorus pesticide azinphos methyl (AM) in the amphipod Hyalella curvispina that inhabits ponds and irrigation channels of an intensive fruit-producing region in Rio Negro and Neuquén valley, North Patagonia, Argentina. The analysis by nonlinear regression of data from the 96 h-acute toxicity tests indicated the coexistence of two subpopulations of H. curvispina with different susceptibilities to AM. The 96 h-LC50 for the resistant subpopulation (166 ± 56 µg/L) was 216-fold higher than the 96h-LC50 value for the susceptible one (0.77 ± 1.33 µg/L).The two subpopulations could not be distinguished based on the biochemical measurements in control amphipods. Cholinesterase activity was significantly inhibited in AM-exposed amphipods in a concentration-dependent manner. The IC50 value obtained after 96 h of exposure (2.18 ± 1.95 µg/L) was significantly lower than the 48 h-IC50 value (29.6 ± 17.4 µg/L). Carboxylesterase activity was significantly inhibited after 48 h of exposure to 12.5 and 62.5 µg/L AM (inhibition, 51%). This enzyme was thus able to protect cholinesterase from inhibition at 12.5 µg/L AM. Reduced glutathione and catalase showed a significant increase after 24 h of exposure as an adaptive response to AM, whereas glutathione S-transferase activity was not significantly modified. The analysis of species sensitivity distribution showed that both subpopulations of H. curvispina were more tolerant to AM than most amphipod species, and that the susceptible subpopulation was more sensitive to AM than the other local aquatic species analyzed. The maximum concentration of AM in drainage water within the fruit-producing area reported by other studies would affect most of the amphipod species (99%) and also a 44% of local aquatic ones. The results obtained in this study point out the usefulness of including amphipods like H. curvispina in ecotoxicity studies and monitoring programs to perform pesticide risk assessments.

Response of biomarkers in amphibian larvae to in situ exposures in a fruit-producing region in North Patagonia, Argentina.

The authors evaluated biomarker responses in caged larvae of the amphibian Rhinella arenarum in water channels during fruit production season and compared them with those elicited by a transient exposure to azinphos methyl (AzM) (0.02-2 mg/L; 4 h), the main pesticide applied in the Alto Valle region, Patagonia, Argentina, taking into account the maximum environmental concentration detected in superficial water (22.5 µg/L). The traditional biomarkers of organophosphate exposure, acetylcholinesterase (AChE) and carboxylesterase, were inhibited in tadpoles after one week of exposure in channels potentially receiving pesticide drift, whereas the antioxidant glutathione (GSH) and the detoxifying activity of GSH S-transferase (GST) were induced. In a two-week monitoring study, AChE activity was induced in larvae exposed at the agricultural site, and carboxylesterase showed an inhibition followed by return to control values, suggesting an exposure-recovery episode. Antioxidant glutathione levels were first depleted and then surpassed control levels, whereas GST activity was continuously induced. These responses were mimicked in the laboratory by 2 mg/L AzM-pulse exposure, which notably exceeds the expected environmental concentrations. The results draw attention to the complexity of responses after pesticide exposure, strongly depending on exposure time-concentration and recovery periods, among other possible factors, and support the necessity of the integrated use of biomarkers to assess exposure episodes in agricultural areas.

Effects of azinphos methyl and carbaryl on Rhinella arenarum larvae esterases and antioxidant enzymes.

Organophosphate (OP) and carbamate pesticides are anticholinesterasic agents also able to alter antioxidant defenses in different organisms. Amphibian larvae are naturally exposed to these pesticides in their aquatic environments located within agricultural areas. We studied the effect of the carbamate carbaryl (CB) and the OP azinphos methyl (AM), compounds extensively used in Northern Patagonian agricultural areas, on reduced glutathione (GSH) levels and the activities of esterases and antioxidant enzymes of the toad Rhinella arenarum larvae. Larvae were exposed 48 h to AM 3 and 6 mg/L or CB 10 and 20 mg/L. Cholinesterase and carboxylesterases were strongly inhibited by CB and AM. In insecticide-exposed larvae, carboxylesterases may serve as alternative targets protecting cholinesterase from inhibition. GSH-S-transferase (GST) activity was significantly increased by CB and AM. Superoxide dismutase activity increased in tadpoles exposed to 6 mg/L AM. Conversely, catalase (CAT) was significantly inhibited by both pesticides. GSH levels, GSH reductase and GSH peroxidase activities were not significantly affected by pesticide exposure. GST increase constitutes an important adaptive response to CB and AM exposure, as this enzyme has been related to pesticide tolerance in amphibian larvae. Besides, the ability to sustain GSH levels in spite of CAT inhibition indicates quite a good antioxidant response. In R. arenarum larvae, CAT and GST activities together with esterases could be used as biomarkers of CB and AM exposure.

Leptodactylus ocellatus (Amphibia): mechanism of defense in the skin and molecular phylogenetic relationships.

Amphibian antimicrobial peptides have been known for many decades and several of them have already been isolated. However, the number of species investigated is still small. Herein, we report on the skin secretions of Leptodactylus ocellatus, which were extracted by mild electrical stimulation and its semi-preparative reverse-phase chromatography was resolved in more than 30 fractions. Among these fractions, two novel antimicrobial peptides were isolated and their amino acid sequences determined by de novo sequencing. The ocellatins-5 and -6 (21 and 22 amino acid residues, respectively) are amidated at the C-terminus. Ocellatins inhibited the growth of reference strains of both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) with minimal inhibition concentration values in the range of 32-128 microg/mL. The amino acid sequence of the peptides shows structural similarity with members of the antimicrobial peptides found in the skin secretion of other leptodactylid frogs. This observation is consistent with the hypothesis that many frog skin antimicrobial peptides are related evolutionarily, having arisen from multiple duplications of an ancestral gene that existed before the radiation of the different species.

Comparação dos padrões de atratividade de Hermetia illucens (Diptera, Stratiomyidae) associada a carcaças de Rattus norvergicus enterradas e tratadas com hormônios esteróides / Comparison of attraction patterns of Hermetia illucens (Diptera, Stratiomyidae) associated to buried Rattus norvergicus carcasses with steroid hormones treatment

Hermetia illucens (L.) (Diptera, Stratiomyidae) é uma espécie abundante em todo o continente americano. No entanto, ainda há poucos estudos no Brasil abordando aspectos em relação a sua biologia e ecologia, em particular associados a estudos forenses. Neste trabalho, nós observamos os efeitos de hormônios esteróides na decomposição corporal de Rattus norvergicus, variedade Wistar enterrados na atração de H. illucens. Além da presença de diversas espécies de larvas e adultos de insetos freqüentemente encontrados em carcaças nessas condições, observou-se uma grande quantidade de imaturos de H. illucens. Essa espécie representou aproximadamente 22 por cento de todos os espécimes coletados, tendo aparecido somente nos animais que receberam tratamento com esteróides sexuais dos tipos testosterona, progesterona e estradiol. Dentre esses, a maior abundância foi verificada nos que haviam recebido testosterona (68 por cento). A presença de imaturos de H. illucens, apenas nos animais que receberam o tratamento com esteróides, em experimentos realizados em dois anos consecutivos revela uma possível atração/seleção dessa espécie por corpos com quantidades aumentadas de hormônios sexuais. Esse comportamento pode ser particularmente útil para a entomologia forense no que diz respeito à estimativa do intervalo pós-morte (IPM), particularmente quando tem como base informações sobre o ciclo de vida e ecologia de insetos necrófagos.

Hermetia illucens (L.) (Diptera, Stratiomyidae) is an abundant species in the entire American continent. Nevertheless, there are few studies in Brazil dealing with aspects of its biology and ecology, particularly associated with forensic studies. In this study we intended to observe the effects of steroids hormones in the corporal decomposition of buried Rattus norvergicus from the Wistar variety in the attraction of H. illucens. Besides the presence of several insect species commonly found in carcasses, a great amount of immature H. illucens was observed. This species represented approximately 22 percent of all collected specimens and it was only found in the animals that have received treatment with sexual steroids, such as testosterone, progesterone and estradiol. Among the animals under treatment, the greater abundance was verified in those who had received testosterone (68 percent). The presence of immatures of H. illucens only in the animals that received hormone treatments in experiments accomplished in two consecutive years strongly suggests a possible attraction of this species for bodies with different amounts of sexual hormones. This behavior can also be relevant for the forensic entomology in regard to the post-mortem interval (PMI) estimation, particularly when the PMI is based on information about the necrophagous insect's life cycle and ecology.