Metal and semimetal loadings in sediments and water from mangrove ecosystems: A preliminary assessment of anthropogenic enrichment in São Tomé island (central Africa).

Mangroves act as buffer areas for marine systems, providing a barrier to contamination from continental sources by retaining metal pollutants. This study evaluates metal and semimetal contamination in the water column and sediments of four mangroves located on the volcanic island of São Tomé. Several metals had a widespread distribution, with occasional high concentrations, linked to potential sources of contamination. However, the two smaller mangroves, located in the northern part of the island, tended to have high metal concentrations. Arsenic and chromium concentrations were notably concerning, particularly if we consider this is an isolated and non-industrialized island. This work highlights the need for further assessments and a better understanding of processes and implications of metal contamination in mangroves. This assumes a particular relevance in areas that have specific geochemical compositions (i.e., volcanic origin) and in developing countries, where people often rely directly and heavily on resources obtained from these ecosystems.

Short-term physical exercise controls age-related hyperinsulinemia and improves hepatic metabolism in aged rodents.

PURPOSE: Aging is associated with changes in glucose homeostasis related to both decreased insulin secretion and/or impaired insulin action, contributing to the high prevalence of type 2 diabetes (T2D) in the elderly population. Additionally, studies are showing that chronically high levels of circulating insulin can also lead to insulin resistance. In contrast, physical exercise has been a strategy used to improve insulin sensitivity and metabolic health. However, the molecular alterations resulting from the effects of physical exercise in the liver on age-related hyperinsulinemia conditions are not yet fully established. This study aimed to investigate the effects of 7 days of aerobic exercise on hepatic metabolism in aged hyperinsulinemic rats (i.e., Wistar and F344) and in Slc2a4+/- mice (hyperglycemic and hyperinsulinemic mice). RESULTS: Both aged models showed alterations in insulin and glucose tolerance, which were associated with essential changes in hepatic fat metabolism (lipogenesis, gluconeogenesis, and inflammation). In contrast, 7 days of physical exercise was efficient in improving whole-body glucose and insulin sensitivity, and hepatic metabolism. The Slc2a4+/- mice presented significant metabolic impairments (insulin resistance and hepatic fat accumulation) that were improved by short-term exercise training. In this scenario, high circulating insulin may be an important contributor to age-related insulin resistance and hepatic disarrangements in some specific conditions. CONCLUSION: In conclusion, our data demonstrated that short-term aerobic exercise was able to control mechanisms related to hepatic fat accumulation and insulin sensitivity in aged rodents. These effects could contribute to late-life metabolic health and prevent the development/progression of age-related T2D.

Effect of a puberty induction protocol based on injectable long acting progesterone on pregnancy success of beef heifers serviced by TAI.

Induction protocols based on progesterone (P4) are used prior to a synchronization program for timed-AI (TAI) to increase number of pubertal heifers and pregnancy per AI (P/AI). Injectable, long-lasting P4 (iP4) is a novel, practical method to supplement P4 in cattle. Here, we aimed to test the effect of an induction protocol based on a single injection of iP4 on P/AI of heifers. Bos indicus (Nellore) heifers were classified as pubertal (PUB; n = 224) or prepubertal (PRE; n = 414) based on two ovarian ultrasonographyc exams conducted 10 d apart. Heifers with a corpus luteum (CL) in any of the exams were considered PUB. Within each puberty status, heifers were assigned to receive nothing (NoiP4) or an induction protocol (iP4). Induction consisted of a single injection of 150 mg of iP4 on D-31, followed by injections of 1 mg of estradiol benzoate (EB) and 150 µg of prostaglandin analogue (PGF) on D-21. On D-9, all heifers received 2 mg of EB + 75 µg of PGF associated to intravaginal P4-device insertion. On D-3, P4-releasing devices were removed and 150 µg of PGF injected. Heifers were inseminated based on estrus on D-1 or were TAI on D0. On D0, all heifers received a dose of GnRH analogue. On D-21, iP4 treatment stimulated a 50% increase in the uterine score (UTS) and a 19% increase in the diameter of the largest follicle of PRE heifers (P < 0.01). On D-9, PRE|iP4 group had a greater proportion (P < 0.01) of CL (63.3%) than PRE|NoiP4 group (11.6%). On D-3, exposure to 6 d P4-releasing device stimulated UTS of PRE|NoiP4 group in a similar fashion than the induction protocol, but it did not have any additional positive effect for PRE|iP4 heifers. P/AI of PRE|iP4 group was similar to that of the PUB groups (44.7 vs 46.9%), but was more than that of PRE|NoiP4 (34.2%). There was an overall 7.7% increment (P = 0.07) on P/AI of iP4 treated heifers (iP4: 46.0% vs. NoiP4: 38.3%). In conclusion, implementation of an induction protocol based on iP4 was efficacious to hasten puberty. Induction stimulated uterine development and follicular growth of prepubertal heifers, ultimately leading to pregnancy success similar to that of pubertal heifers.

Epimastigogénesis de Trypanosoma cruzi: método para estudiar in vivo la transformación de tripomastigota en epimastigota / Trypanosoma cruzi epimastigogenesis: a method for studying Trypomastigote to epimastigote transformation in vivo

La epimastigogénesis de Trypanosoma cruzi ocurre naturalmente en el intestino del hospedador invertebrado. Se desconoce si los cambios morfológicos que ocurren durante la transformación de los tripomastigotas sanguíneos en epimastigotas son idénticos para diferentes aislados de T. cruzi. Aquí mostramos un método útil para estudiar los eventos que ocurren durante la epimastigogénesis, comparando parásitos de diferentes procedencias epidemiológicas. Se alimentaron artificialmente ninfas de V estadio de Rhodnius prolixus con una solución ad hoc conteniendo tripomastigotas tipo-sanguíneo y siguiendo los cambios morfológicos por 8 días. Los contenidos del intestino anterior de las ninfas se obtuvieron decapitando y comprimiendo el abdomen lo que permitió obtener rápidamente casi 100% del inóculo con cargas entre 1,9 y 8,9 × 106 tripomastigotas/ninfa. El número de parásitos por ninfa y los cambios morfológicos se determinaron por Microscopia de Contraste de Fases y coloración con Giemsa. Las ninfas ingirieron 7,4 veces su peso de solución infectante, con volúmenes entre 101 y 357 µL (229 ± 66 mg), 50% de esa ingesta se eliminó como orina durante las primeras 24 h. Los tripomastigotas se transformaron en formas redondeadas antes de evolucionar a epimastigotas, siguiendo cinéticas diferentes según el aislado. Proponemos esta metodología para estudiar rápida y cuantitativamente los eventos tempranos de la epimastigogénesis de T. cruzi in vivo.

Trypanosoma cruzi epimastigogenesis naturally occurs in the intestine of the invertebrate host. It is not known whether the morphological changes that occur during transformation of bloodstream trypomastigotes to epimastigotes are identical for different T. cruzi isolates. This research shows a useful method for studying the events that occur during epimastigogenesis, comparing parasites from epidemiological sources. Rhodnius prolixus V stage nymphs were fed artificially with an ad hoc solution containing blood-like trypomastigotes and the morphological changes were examined during eight days. Anterior intestinal contents were removed by decapitation and squeezing the abdomen of the nymphs, which permitted obtaining quickly almost 100% of the inoculate with loads between 1.9 and 8.9 × 106 trypomastigotes/nymph. The number of parasites per nymph and morphological changes were determined using phase microscopy with Giemsa staining. The nymphs ingested 7.4 times their weight of the infecting solution with volumes between 101 e 357 µL (229 ± 66 mg); 50% of the ingest was eliminated as urine during the first 24 hours. The trypomastigotes transformed to rounded forms before evolving into epimastigotes following different kinetics according to the isolate. This method is proposed for rapid, quantitative study of the early events of epimastigogenesis for T. cruzi in vivo.

RAPD and ISSR markers in the evaluation of genetic divergence among accessions of elephant grass.

Considering the expected genetic variability of elephant grass (Pennisetum purpureum), due to its cultivation in different continents, we characterized and estimated the genetic divergences between 46 accessions of elephant grass with different edaphoclimatic adaptations, using RAPD and ISSR markers. We evaluated, comparatively, the consistency of the information achieved with these markers. Twenty-six RAPD and 25 ISSR primers were employed. The RAPD markers produced 185 bands, 72% of which were polymorphic, with a mean of 5.11 polymorphic bands per primer. The 25 ISSR starters produced 216 bands; 76% were polymorphic, with a mean of 6.56 polymorphic bands per primer. The correlation between the genetic distances achieved by the RAPD and ISSR markers was 0.76, which is highly significant by the Mantel test. Based on UPGMA grouping, considering the point of sudden change, five and six groups were formed for the data from the RAPD and ISSR markers, respectively. These markers provided partially concordant groups, indicating that these techniques can provide consistent information and consequently could be used in studies of genetic diversity among accessions.

In situ infrared (FTIR) study of the mechanism of the borohydride oxidation reaction.

Early reports stated that Au was a catalyst of choice for the BOR because it would yield a near complete faradaic efficiency. However, it has recently been suggested that gold could yield to some extent the heterogeneous hydrolysis of BH, therefore lowering the electron count per BH, especially at low potential. Actually, the blur will exist regarding the BOR mechanism on Au as long as no physical proof regarding the reaction intermediates is not put forward. In that frame, in situ physical techniques like FTIR exhibit some interest to study the BOR. Consequently, in situ infrared reflectance spectroscopy measurements (SPAIRS technique) have been performed in 1 M NaOH/1 M NaBH(4) on a gold electrode with the aim to detect the intermediate species. We monitored several bands in B-H (nu ∼ 1180, 1080 and 972 cm(-1)) and B-O bond regions (nu = 1325 and ∼1425 cm(-1)), which appear sequentially as a function of the electrode polarization. These absorption bands are assigned to BH(3), BH(2) and BO species. At the light of the experimental results, possible initial elementary steps of the BOR on gold electrode have been proposed and discussed according to the relevant literature data.

Pterygodermatites ( Multipectines) pluripectinata n. sp. (Spirurida: Rictulariidae), a nematode parasite of the crab-eating fox Cerdocyon thous (Linnaeus, 1766) from Caatinga shrubland, Brazil.

In a parasitological survey of free-ranging Cerdocyon thous (Carnivora: Canidae) from Brazilian Caatinga shrubland, a new species of Pterygodermatites (Multipectines) was recovered from the small intestine of this host. Morphological analysis showed that P. (Multipectines) pluripectinata n. sp. is distinguished from all other congeneric species mainly by the numerous plate-like projections and male caudal morphology and spicular length. There are few records on the occurrence of this genus in Neotropical regions.

Helminthological records of six-banded armadillos Euphractus sexcinctus (Linnaeus, 1758) from the Brazilian semi-arid region, Patos county, Paraíba state, including new morphological data on Trichohelix tuberculata (Parona and Stossich, 1901) Ortlepp, 1922 and proposal of Hadrostrongylus ransomi nov. comb.

This work aimed to evaluate the gastrointestinal helminthfauna composition of six-banded armadillos from the Brazilian semi-arid region. Gastrointestinal contents of six road-killed adult animals from Patos County, Paraíba State, were analyzed. Six species of nematodes, comprising five genera and four families, were recovered from the analyzed animals. New morphological data on Trichohelix tuberculata is given, along with a new taxonomical proposal for Hadrostrongylus ransomi (Travassos, 1935) n. comb. This is the first record for parasitic helminths in this host from the Brazilian semi-arid.

Helminthological records of six-banded armadillos Euphractus sexcinctus (Linnaeus, 1758) from the Brazilian semi-arid region, Patos county, Paraíba state, including new morphological data on Trichohelix tuberculata (Parona and Stossich, 1901) Ortlepp, 1922 and proposal of Hadrostrongylus ransomi nov. comb. / Registros helmintológicos em tatus-peba Euphractus sexcinctus (Linnaeus, 1758) do semi-árido brasileiro, município de Patos, Paraíba, com dados acerca da morfologia de Trichohelix tuberculata (Parona and Stossich, 1901) Ortlepp, 1922 e proposição de Hadrostrongylus ransomi nov. comb.

This work aimed to evaluate the gastrointestinal helminthfauna composition of six-banded armadillos from the Brazilian semi-arid region. Gastrointestinal contents of six road-killed adult animals from Patos County, Paraíba State, were analyzed. Six species of nematodes, comprising five genera and four families, were recovered from the analyzed animals. New morphological data on Trichohelix tuberculata is given, along with a new taxonomical proposal for Hadrostrongylus ransomi (Travassos, 1935) n. comb. This is the first record for parasitic helminths in this host from the Brazilian semi-arid.

Este trabalho teve como objetivo avaliar a composição da helmintofauna gastrintestinal de tatus-peba da região semi-árida brasileira. Conteúdos gastrintestinais de seis animais adultos atropelados nas rodovias do município de Patos, Paraíba, foram analisados. Seis espécies de nematódeos agrupados em cinco gêneros e quatro famílias foram obtidas. Novos dados morfológicos de Trichohelix tuberculata são relatados, e ainda é proposto Hadrostrongylus ransomi (Travassos, 1935) n. comb. Este é o primeiro relato de helmintos parasitas deste hospedeiro no semi-árido brasileiro.

Treatment of inflammatory internal root resorption with mineral trioxide aggregate: a case report.

AIM: To report the treatment and follow-up of a maxillary central incisor with internal resorption managed by root canal treatment, white mineral trioxide aggregate (MTA) repair and a fibre-glass post for reinforcement. SUMMARY: This study presents a case of extensive internal root resorption affecting tooth 11 (FDI) in a 28-year-old male patient, with a history of trauma in that region. The substantial loss of tooth structure, including cementum, and a perforation with lateral periodontal communication were complicating factors. Despite a guarded prognosis but encouraged by a healthy periodontal condition, treatment based on reconstructing the tooth with white MTA and a fibre-glass core was carried out. Follow-up radiographs over 20 months demonstrated the maintenance of a functional tooth. The tooth did, however, discolour after MTA treatment. KEY LEARNING POINTS: Because of its insidious pathology, internal root resorption can extend to significant dimensions before being recognized. MTA plus the fitting of a fibre-glass post provided adequate, functional rehabilitation of a compromised tooth for 20 months. Despite the favourable biological and mechanical properties of white MTA, considerable tooth discolouration may occur.

Antigenotoxicity and antimutagenicity of lycopene in HepG2 cell line evaluated by the comet assay and micronucleus test.

Epidemiological studies have provided evidence that high consumption of tomatoes effectively reduces the risk of reactive oxygen species (ROS)-mediated diseases such as cancer. Tomatoes are rich sources of lycopene, a potent singlet oxygen-quenching carotenoid. In addition to its antioxidant properties, lycopene shows an array of biological effects including antimutagenic and anticarcinogenic activities. In the present study, the chemopreventive action of lycopene was examined on DNA damage and clastogenic or aneugenic effects of H2O2 and n-nitrosodiethylamine (DEN) in the metabolically competent human hepatoma cell line (HepG2 cells). Lycopene at concentrations of 10, 25, and 50 microM, was tested under three protocols: before, simultaneously, and after treatment with the mutagen, using the comet and micronucleus assays. Lycopene significantly reduced the genotoxicity and mutagenicity of H2O2 in all of the conditions tested. For DEN, significant reductions of primary DNA damage (comet assay) were detected when the carotenoid (all of the doses) was added in the cell culture medium before or simultaneously with the mutagen. In the micronucleus test, the protective effect of lycopene was observed only when added prior to DEN treatment. In conclusion, our results suggest that lycopene is a suitable agent for preventing chemically-induced DNA and chromosome damage.

Lycopene activity against chemically induced DNA damage in Chinese hamster ovary cells.

Lycopene is a natural pigment synthesized by plants and microorganisms, and it is mainly found in tomatoes. It is an acyclic isomer of beta-carotene and one of the most potent antioxidants. Several studies have demonstrated the ability of lycopene to prevent chemically induced DNA damage; however, the mechanisms involved are still not clear. In the present study, we investigated the antigenotoxic/antimutagenic effects of lycopene in Chinese Hamster Ovary Cells (CHO) treated with hydrogen peroxide, methylmethanesulphonate (MMS), or 4-nitroquinoline-1-oxide (4-NQO). Lycopene (97%), at final concentrations of 10, 25, and 50 microM, was tested under three different protocols: before, simultaneously, and after the treatment with the mutagens. Comet and cytokinesis-block micronucleus assays were used to evaluate the level of DNA damage. Data showed that lycopene reduced the frequency of micronucleated cells induced by the three mutagens. However, this chemopreventive activity was dependent on the concentrations and treatment schedules used. Similar results were observed in the comet assay, although some enhancements of primary DNA damage were detected when the carotenoid was administered after the mutagens. In conclusion, our findings confirmed the chemopreventive activity of lycopene, and showed that this effect occurs under different mechanisms.

FTIR study of the ethanol electrooxidation on Pt(100) modified by osmium nanodeposits.

In the present work, ethanol electrooxidation on a Pt(100) electrode modified by different coverage degrees of osmium nanoislands obtained by spontaneous depositions, was extensively studied employing in situ FTIR spectroscopy. A collection of spectra of the ethanol adsorption and oxidation processes was acquired during the first series of a positive potential step, to determine the intermediate species, as well as the main products formed. The spectroscopic results obtained were correlated with conventional electrochemical results obtained by cyclic voltammetry. It was shown that the catalytic activity of Pt(100) for ethanol oxidation increases significantly after osmium deposition and that the mechanistic pathway for this reaction depends directly on the osmium coverage degree. Thus, for low osmium coverage (theta;( Os) up to 0.15) the formation of CO as an intermediate was favored and hence the full oxidation of adsorbed ethanol to CO(2) was increased. For higher osmium coverages (theta;(Os) up to 0.33), the higher the coverage is, the more the direct ethanol oxidation to acetaldehyde and acetic acid is favored. For osmium coverage degree of 0.40, the catalytic activity of the electrode for ethanol oxidation decreased. On an almost complete osmium layer (theta;(Os) = 0.92) obtained by electrodeposition at 50 mV vs reversible hydrogen electrode, the catalytic activity for ethanol oxidation shows a much lower value.

Identity by descent and candidate gene mapping of Richieri-Costa and Pereira syndrome.

The Richieri-Costa-Pereira syndrome is a rare autosomal recessive disorder characterized by short stature, Robin sequence, cleft mandible, pre/postaxial anomalies and clubfoot. Of 15 families reported with this disorder 14 are from Brazil suggesting a founder effect. We studied 15 families using identity-by-descent as a hypothesis to attempt gene localization We have examined through linkage analysis 497 polymorphic-markers and also performed direct sequencing of exons for 10 candidate genes selected on the basis of their expression in the developing mandible and limb. No evidence for allele sharing at any locus tested or mutations in candidate genes was found. Additional higher resolution mapping, new families and other candidate genes might improve future chances of gene identification.

Study on the mutagenicity and antimutagenicity of a natural food colour (annatto) in mouse bone marrow cells.

Most manufactured foods contain chemicals added as a deliberate part of the manufacturing process. The aims of the present study were to evaluate the mutagenicity and antimutagenicity of annatto, a natural pigment extracted from the Bixa orellana L. and widely used as a colorant in foods. The micronucleus test was performed in bone marrow cells from Swiss male mice treated with one of the three concentrations of annatto (1330, 5330 and 10,670 ppm), incorporated into the diet. The animals were fed with the diets for 7 days and sacrificed 24 h after the last treatment. For the evaluation of the antimutagenic potential of annatto, at day 7, the animals received an intraperitoneal injection of cyclophosphamide (50 mg/kg body weight). Under the concentrations tested annatto did not present mutagenic or antimutagenic activities on the mice bone marrow cells. However, an increased frequency of micronucleated cells was observed when the highest concentration (10,670 ppm) was administered simultaneously with cyclophosphamide. In conclusion, the data indicate that annatto colour, for the conditions used, is neither mutagenic nor an inhibitor of induced mutations, although it should be used carefully since high doses may increase the effect of a mutagen.

Rice straw as a support for immobilization of microbial lipase.

Candida rugosa lipase was covalently immobilized on rice straw activated with glutaraldehyde using poly(ethylene glycol) (PEG) as the stabilizing agent. The effects of PEG molecular weight and enzyme loading were studied according to a full 2(2) factorial design. Higher immobilization yields (>70%) were attained when the lipase loading was 95 units/mg of dry support, independent of PEG molecular weight. All derivatives showed high hydrolytic and synthetic activities. This work provides preliminary results on the use of agricultural residues as a support matrix for immobilizing lipase and on the application of the resulting derivatives to butyl butyrate synthesis as a study model.

Frequency of Trichomonas vaginalis, Candida sp and Gardnerella vaginalis in cervical-vaginal smears in four different decades.

CONTEXT: Vaginitis is one of the principal motives that lead women to seek out an obstetrician or gynecologist. Bacterial vaginosis, candidiasis and trichomoniasis are responsible for 90% of the cases of infectious vaginitis. OBJECTIVE: To verify the frequency of the three main causative agents of vaginitis, Trichomonas vaginalis, Candida sp and Gardnerella vaginalis, in four different decades (1960's, 1970's, 1980's and 1990's). DESIGN: Retrospective. PLACE: A tertiary referral center. PARTICIPANTS: Patients attended to as gynecology and obstetrics outpatients at the Faculdade de Medicina do Triângulo Mineiro during the years 1968, 1978, 1988, 1998, taken as samples of each decade. MAIN MEASUREMENTS: Diagnoses of infection by Trichomonas vaginalis, Candida sp and Gardnerella vaginalis were gathered from 20,356 cervical-vaginal cytology tests on patients attended to as gynecology outpatients at Faculdade de Medicina do Triângulo Mineiro during the years 1968, 1978, 1988, 1998, representing the four decades. The results were grouped according to the age group of the patients: under 20, between 20 and 29, between 30 and 39, between 40 and 49, and 50 or over. Statistical analysis was done via the chi-squared (Mantel-Haentzel) test with a significance level of 5%. RESULTS: In 1968 infections by Trichomonas vaginalis and Candida sp were diagnosed in 10% and 0.5% of the cytology tests and in 1978, 5.1% and 17.3%, respectively (P < 0.0001). Infection by Gardnerella vaginalis could only be evaluated in the latter two decades. In 1988, 19.8% of the women had positive tests for Gardnerella vaginalis, which was the most frequent agent in that year, diminishing in the subsequent decade to 15.9% (P < 0.0001). Candidiasis was the most frequent infection in 1998, detected in 22.5% of the tests (P < 0.0001). In a general manner, all the infections were most frequent among younger patients, especially those aged under 20, in all decades, whereas infections were least frequent among patients aged 50 or over (P < 0.05). CONCLUSION: There was a reduction in the frequency of cervical-vaginal infection by Trichomonas vaginalis and an increase in the frequency of Candida sp over the four decades studied. All the infections were most frequent in patients aged under 20 years.

Antagonism of Trichoderma species on Cladosporium herbarum and their enzimatic characterization

O maracujá (Passiflora edulis Sims.), um fruto tropical amplamente consumido, tem sua produção e a qualidade dos seus frutos reduzidos pela verrugose causada por Cladosporium herbarum. Este trabalho objetivou investigar o antagonismo de espécies de Trichoderma (T. polysporum, T.koningii, T. viride e T. harzianum) contra C. herbarum, e estudar a produção de enzimas hidrolíticas extracelulares pelo fitopatógeno e antagonistas. Os resultados mostraram considerável potencial antagônico para o biocontrole dos isolados de C. herbarum por todas as espécies de Trichoderma, exceto T. koningii. O efeito mais promissor foi observado para T. polysporum. Em relação ao padrão de esterase obtido por eletroforese em gel de poliacrilamida, a maior atividade apresentada pelos isolados foi observada cinco dias após a incubação. Os isolados de C. herbarum produziram enzimas extracelulares, lipase, pectinase, cellulase e protease, todas possivelmente relacionadas ao processo de infecção do hospedeiro. A excreção de amilase que parece não estar associada com fitopatógenos foi detectada nas espécies de Trichoderma, mas não em C. herbarum. Além disso, todas as espécies de Trichoderma testadas produziram também celulase e pectinase, exceto T. koningii com relação a esta última enzima. A demonstração de várias isoesterases no zimograma das espécies de Trichoderma e isolados de C. herbarum, foi notavelmente melhorada através da lavagem do micélio com detergentes ou EDTA. Este fato sugere que uma grande fração de enzimas extracelulares pode permanecer presa externamente na parede celular fúngica após excreção.