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PURPOSE: Considering the importance of parental attitudes and their influence on children's oral health, it is important to know which characteristics may impact it. The aim of this population study was to evaluate the impact of the parental sociodemographic characteristics on the oral health-related quality of life (OHRQoL) of preschool children from southeastern Brazil. METHODS: A population-based study was conducted with a sample of 321 children aged 2 to 5 years old who underwent a calibrated clinical oral examination to assess oral health status and their parents were asked to answer the two following questionnaires: (1) sociodemographic conditions and (2) Brazilian version of the Early Childhood Oral Health Impact Scale (B-ECOHIS). Descriptive analysis, Mann-Whitney and Kruskal-Wallis tests and adjusted Poisson regression models were used. RESULTS: Younger mothers (RP: 1.47; 95% CI: 1.11-1.95), lower household income (RP: 1.47; 95% CI: 1.11-1.96) and the presence of dental caries (RP: 2.28; 95% CI: 1.74-3.0) were more likely to have a negative impact on the OHRQoL B-ECOHIS total scores (P < 0.01). CONCLUSION: The characteristics of mothers, such as age, schooling and salary, influenced the mean B-ECOHIS total score; however, paternal attributes were not associated with a negative impact on the children's quality of life. Also, dental caries and household income influenced the children's oral health-related quality of life.

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BACKGROUND: Indiscriminate use of antimicrobials in neonatal sepsis treatment contributes to consumption misuse, and the optimization of prescription programmes is encouraged as a way of reducing this inappropriate use. AIM: To evaluate the impact of intervention programmes for adequate antimicrobial use (antimicrobial stewardship programmes) in consumption measurements of such drugs in neonatology. METHODS: The search for articles was performed in electronic databases and by manual search for citations in publications initially identified. Electronic databases searched were BVS (Virtual Health Library), Cochrane Library, Embase, MEDLINE/PubMed, SciELO, Scopus, and Web of Science. There was no date or period limit for inclusion of articles. The PICO question was defined as populations of neonates admitted to neonatal intensive care units undergoing an intervention programme to optimize antimicrobial therapy in relation to neonates not exposed to the programme and the outcome obtained in antimicrobials consumption. FINDINGS: The initial search in databases resulted in 1223 articles. Articles were screened and 16 original studies related to subject were selected, which conducted a quantitative approach to antimicrobials consumption for the population of interest. Most articles used days of therapy (DOT) as the main measure of antimicrobial consumption and have had a high-quality rating by Newcastle-Ottawa Scale. All studies were carried out in local hospitals at a single centre and most were in high-income countries. CONCLUSION: Of all studies identified by the search, few evaluated antimicrobial consumption in neonatology. New studies are needed, and DOT was shown to be the most adequate metric to measure consumption.

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Due to the supposed involvement of minerals in cases of ruminant periodontitis, this study aimed to analyze the concentrations of phosphorus (P) in bone, and cobalt (Co), copper (Co), iron (Fe), zinc (Zn) and selenium (Se) in liver of a cohort of sheep affected or not by periodontitis. From an outbreak of the disease in 2011 in Pará state, Brazil, rib and liver samples were obtained from 22 sheep with periodontitis and seven samples from healthy animals. Based on the concentrations of the different minerals in the tissues, we concluded that there was no relationship between periodontal disease in sheep with any mineral deficiency status. In contrast, most of the minerals in the tissues were above or within the recommended concentrations in bone and liver. Within the various aspects which until now have been studied regarding periodontitis in ruminants, the results obtained here corroborate the fact that periodontal disease in sheep is an infectious disease and it is not a consequence of the deficiency or excess of mineral elements in the diet.

Devido ao suposto envolvimento de minerais em casos de periodontite em ruminantes, este trabalho teve como objetivo analisar as concentrações de fósforo (P) nos ossos, além de cobalto (Co), cobre (Co), ferro (Fe), zinco (Zn) e selênio (Se), no fígado de ovelhas afetadas ou não por periodontite. De um surto da doença em 2011, no estado do Pará, Brasil, foram obtidas amostras de costelas e fígado de 22 ovelhas com periodontite e sete amostras de animais saudáveis. Com base nas concentrações dos diferentes minerais nos tecidos, conclui-se que não houve relação entre a doença periodontal em ovinos com qualquer estado de deficiência mineral. A maioria dos minerais estava acima ou dentro das concentrações recomendadas, seja no tecido ósseo, seja no hepático. Entre os diversos aspectos até agora estudados sobre a periodontite em ruminantes, os resultados obtidos corroboram o fato de a doença periodontal em ovinos ser uma doença infecciosa e não decorrente da deficiência ou do excesso de elementos minerais na dieta.

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Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.

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ABSTRACT: In Brazil, contamination of raw milk with Mycobacterium tuberculosis complex (MTC) has been reported in several states. The highest rate of consumption of raw milk and its derivatives in Brazil occurs in Amazonas. This state also has the highest prevalence of tuberculosis in both humans and livestock. We assessed the contamination of cow's milk and buffalo's milk with MTC in Amazonas, focusing on Mycobacterium bovis, the species most commonly found in cattle and buffalo. In 2019, 250 samples of raw milk (91 from cattle, 159 from buffalo) were collected before processing from three milk plants in the state of Amazonas. The samples were placed into 21 pools and analyzed using shotgun metagenomic sequencing and taxonomic classification with Kraken 2 and MegaBLAST. To confirm the identity of mycobacterial species found, BLASTN was used to identify specific genomic positions in the TbD1 and RD1 regions and flanking RD4 region. MTC genetic material was identified in all pools of raw milk. Genetic material consistent with M. bovis was identified in seven pools of raw milk (1 from cattle, 6 from buffalo). Buffalo's milk had significantly higher MTC reads than did cow's milk. The common practice of consumption of raw milk and its derivatives in Amazonas presents a risk to public health. Urgent measures to prevent transmission of foodborne tuberculosis are needed in the Amazon region. Greater efforts and resources also should be directed toward elimination of bovine tuberculosis in cattle and buffalo herds in Amazonas and the rest of Brazil.

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PURPOSE: This study sought to evaluate in vitro the effect of a dentifrice containing sodium trimetaphosphate (TMP) combined or not with low fluoride (500 ppm NaF) on dentine erosion of intrinsic origin. METHODS: Human root dentine blocks were selected based on surface microhardness and randomly allocated into five groups (n = 12): negative control (0 ppm F; no TMP); F500 (500 ppm NaF); F1500 (1500 ppm NaF-positive control); TMP (1% TMP); and F + TMP (500 ppm NaF + 1% TMP). The blocks were submitted to erosion cycles (3 ×/day) for 3 days (0.01 M HCl, pH 1.5-30 s), treatment (1 min-1:3 p/p dentifrice/distilled water) and remineralization (artificial saliva/120 min). Dentine alterations were determined according to the percentage of microhardness loss (%HL), surface loss (SL) and surface analysis by scanning electron microscopy. The data were analyzed using one-way ANOVA (p < 0.05). RESULTS: The values of SL and %HL in each group were, respectively: negative control (1.36 ± 0.36; 57.29 ± 14.14), F500 (1.46 ± 0.28; 65.66 ± 5.11), F1500 (1.52 ± 0.36; 61.66 ± 5.15), TMP (1.45 ± 0.45; 62.08 ± 3.83) and F + TMP (1.38 ± 0.42; 63.38 ± 6.47). There was no statistically significant difference in all the parameters (p = 0.873 and p = 0.152). CONCLUSION: The dentifrices containing TMP combined or not with fluoride were not able to prevent dentine erosion.

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INTRODUCTION: Developmental Defects of Enamel (DDEs) comprise qualitative and/or quantitative changes to the enamel during amelogenesis. The aetiology of DDE remains inconclusive. AIM: To determine the association of pre, peri, and postnatal factors with the presence of DDE. DESIGN: Cross-sectional study with 353 children (8 to 11 years-old) in a Brazilian town. METHODS: One calibrated dentist assessed DDE using the Developmental Defects of Enamel Index and a questionnaire collected medical and sociodemographic data. MAIN OUTCOMES: Children with at least one type of DDE were categorized into the DDE group. Subtypes of DDE were also recorded. RESULTS: 63.1% of children had at least one type of DDE. Diffuse opacity was present in 36.7%, demarcated opacity in 14.8%, and hypoplasia in 5.83% of the children. In multivariate analysis, demarcated opacities and hypoplasia were associated with birth weight ⟨ 2500g (OR = 4.82; 95% CI 1.23-1.95). CONCLUSION: Low birth weight predicted DDE.

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Crude glycerin (CG) is a biodiesel byproduct that has been tested as an alternative feed additive for use in beef production. After being absorbed, it is used in the liver to produce glucose, an important precursor of intramuscular fat in ruminants. This study aimed to evaluate the effect of CG (439 g/kg glycerol) on the performance and meat quality of crossbred heifers finished in Urochloa brizantha cv. Marandu. Thirty-six heifers with an initial BW of 301.5 ±â€¯23.02 kg were used. They were supplemented for 154 days with the following levels of CG: mineral mixture (without CG), 33.3, 66.6 and 99.9 g/kg CG in the DM of the supplement. Supplement or pasture DM intakes, slaughter BW and carcass traits were not influenced (P > 0.05) by increasing levels of CG. The total fat content of the meat, the vaccenic (18:1 n-7t) and conjugated linoleic acid (18:2 c9-t11) increased with the addition of CG in the diet (P < 0.05). Crude glycerin can be included up to 99.9 g/kg of the total diet without changing the performance of crossbred heifers finished in the tropical pasture.

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PURPOSE: Evidence has shown an inverse correlation between previous dental care experience and anxiety levels in children. This study aimed to determine the prevalence of dental anxiety in Brazilian schoolchildren and to evaluate the association between previous experience with the dentist and anxiety and fear of pain. METHODS: This was a cross-sectional descriptive study carried out in two cities in Brazil with 1191 schoolchildren aged 6-12 years. The data were collected through interviews and clinical examination. The interviews followed the Dental Anxiety Question (DAQ), the Fear of Dental Pain Questionnaire Short Form (S-FDPQ) adapted to children, and some sociodemographic questions. RESULTS: Dental anxiety was more prevalent in the younger group, with a higher prevalence of moderate and severe anxiety. The group with extreme anxiety showed a higher prevalence of extreme fear, whereas the group who did not present anxiety showed a higher prevalence of children with moderate fear of pain. Children who had not visited the dentist showed a higher prevalence of fear and a lot of fear (33.5%) as compared to those who had already experienced dental care (13.9%). The prevalence of severe anxiety and extreme fear of pain was higher in the group of female children aged 6-9 years, and with caries experience (P < 0.001). CONCLUSIONS: The experience with the dentist was associated with less anxiety and fear of pain. The age of the child was a determining factor for changes in their anxiety level. Severe dental anxiety influences fear of pain experienced by the child.

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Wild birds carry a number of infectious agents, some of which may have pathogenic potential for the host and others species, including humans. Domestic pigeons (Columba livia) are important targets of study since these increasingly cohabit urban spaces, being possible spillover sources of pathogens to humans. In the present study, two genomes (PiGyV_Tq/RS/Br and PiGyV_RG/RS/Br), representative of Gyrovirus genus, family Anelloviridae, were detected in sera of free-living pigeons collected in Southern Brazil. The genomes exhibit less than 50% identity to previously described members of Gyrovirus genus, suggesting that they constitute a new viral species circulating in pigeons, to which the name "pigeon gyrovirus (PiGyV)" is proposed. The current study characterizes these two PiGyV genomes which, to date, are the first gyrovirus species identified in domestic pigeons.

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Integrated control tactics are often necessary for pest management. This is especially true for organisms such as the two-spotted spider mite, Tetranychus urticae Koch. The management of this mite pest species relies on pesticide use, but its short life cycle associated with high selection pressure results in frequent problems of acaricide resistance and population outbreaks. Therefore, combining acaricides and natural enemies is an appealing strategy for managing this pest species. The predatory mite Neoseiulus idaeus Denmark & Muma (Phytoseiidae) is important in arid environments, where other natural enemies show low efficacy. Thus, we investigated the effects of representative acaricides used for managing spider mites around the world in several crops (i.e., abamectin, fenpyroximate, and azadirachtin), on the functional and numerical responses of the phytoseid predator N. idaeus to increasing egg densities of its prey. Acaricide exposure did not affect the type of N. idaeus functional response or attack rate (a). However, acaricide exposure decreased the amount of consumed prey and increased prey handling time (Th). All acaricides affected the numerical response of the predator, which reduced oviposition rates. Therefore, caution is required in attempts to integrate the control methods.

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Previous studies in our laboratory have suggested that P2X7 could contribute to the progression of diabetic nephropathy and modulated klotho expression. The aim of this study was to investigate if P2X7 receptor is related to the expression of klotho in the onset of diabetic nephropathy in rats. Seven-week-old male Wistar rats weighing 210 g were all uninephrectomized; two-third of the animals were induced to diabetes with 60 mg/kg streptozotocin i.v., and one-third received its vehicle (control rats). At 4th day of the fifth week of the protocol, half of the diabetic rats received a small interfering RNA targeting for P2X7 mRNA, and the other half received its vehicle. Euthanasia was made at the eighth week. Diabetic animals reproduced all classic symptoms of the disease; besides, they showed reduced renal function and low NO bioavailability; also, SOD1, SOD2, and catalase were increased, probably due to the oxidative stress which was elevated in this situation. Metabolic data of diabetic rats did not change by silencing P2X7 receptor. For the other hand, silencing P2X7 was able to contribute to balance oxidative and nitrosative profile, ultimately improving the renal function and increasing plasma and membrane forms of klotho. These findings suggest that the management of P2X7 receptor can benefit the kidneys with diabetic nephropathy. Further studies are needed to show the therapeutic potential of this receptor inhibition to provide a better quality of life for the diabetic patient.

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Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection in cystic fibrosis (CF) patients has been associated with a more rapid decline in lung function, increased hospitalisation and mortality. The aim of this study was to evaluate the clonal relationships among 116 MRSA isolates from 12 chronically colonised CF pediatric patients over a 6-year period in a Rio de Janeiro CF specialist centre. Isolates were characterised by antimicrobial resistance, SCCmec type, presence of Panton-Valentine Leukocidin (PVL) genes and grouped according to DNA macrorestriction profile by pulsed-field gel electrophoresis (PFGE) and spa gene type. High resistance rates were detected for erythromycin (78%) and ciprofloxacin (50%) and SCCmec IV was the most common type (72.4%). Only 8.6% of isolates were PVL positive. High genetic diversity was evident by PFGE (39 pulsotypes) and of nine that were identified spa types, t002 (53.1%) and t539 (14.8%) were the most prevalent. We conclude that the observed homogeneity of spa types within patients over the study period demonstrates the persistence of such strain lineages throughout the course of chronic lung infection.

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Interactions between different pest control methods can affect Integrated Pest Management efficiency. This study sought to evaluate (1) if Si accumulation is related to the level of constitutive resistance in sorghum genotypes, (2) the level of Si induces resistance by antibiosis in sorghum genotypes with different levels of constitutive resistance to Schizaphis graminum (Rondani) (reared individualized or in colonies), and (3) the fitness of Lysiphlebus testaceipes (Cresson) in aphids reared on Si-treated and untreated plants. Several experiments were conducted under greenhouse conditions, using sorghum genotypes with different levels of resistance grown in pots with or without the addition of Si to the soil. The susceptible (BR007B), moderately resistant (GB3B), and highly resistant (TX430XGR111) genotypes all absorbed more Si when it was added to the soil compared with when it was not amended. However, the final Si content of treated plants was not related to the level of constitutive resistance among treated genotypes. While Si soil application did reduce the fecundity of individualized aphids reared on the susceptible and moderately resistant sorghum plants, it did not reduce populational growth of aphid colonies, independent of the level of plant's constitutive resistance. Parasitoid (L. testaceipes) had higher weight when reared from aphids fed on plants with added Si. Sorghum × constitutive resistance × S. graminum interactions were affected by plant Si content only for individualized aphids but not for aphid colonies. Sorghum × S. graminum × L. testaceipes interactions suggest that Si can have, overall, a positive effect on the biological control of S. graminum.

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Because plant phenotypes can change in response to attacks by herbivores in highly variable ways, the distribution of herbivores depends on the occurrence of other herbivore species on the same plant. We carried out a field study to evaluate the co-occurrence of three coconut pests, the mites Aceria guerreronis (Acari: Eriophyidae), Steneotarsonemus concavuscutum (Acari: Tarsonemidae) and the moth Atheloca bondari (Lepidoptera: Pyralidae). The eriophyid mite Ac. guerreronis is the most important coconut pest around the world, whereas S. concavuscutum and At. bondari are economically important only in some areas along the Brazilian coast. A previous study suggested that the necrosis caused by Ac. guerreronis facilitates the infestation of At. bondari larvae. Because all three species infest the area under the perianths on coconuts and S. concavuscutum also causes necrosis that could facilitate At. bondari, we evaluated the co-occurrence of all three species. We found that the occurrence of At. bondari was positively associated with Ac. guerreronis, but negatively associated with S. concavuscutum. In addition, the two mite species showed negative co-occurrence. Atheloca bondari was found on nuts of all ages, but more on nuts that had fallen than on those on the trees, suggesting that nuts infested by At. bondari tend to fall more frequently. We discuss the status of At. bondari as a pest and discuss experiments to test the causes of these co-occurrence patterns.

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AIM: To evaluate the effects of P2X7 receptor blockade on renin-angiotensin system (RAS) in rats with diabetic nephropathy (DN). MAIN METHODS: Wistar rats were unilaterally nephrectomized and received streptozotocin for diabetes mellitus (DM) induction; control animals (CTL) received the drug vehicle. The animals were submitted to P2X7 receptor silencing, forming the group (DM + siRNA). The animals were placed in metabolic cages for data collection and evaluation of renal function; at the end of the protocol, the kidney was removed for analysis of P2X7, renin, angiotensin-converting enzyme (ACE), ACE2, angiotensin, thiobarbituric acid reactive substance levels (TBARS), nitric oxide (NO) and qualitative histological. KEY FINDINGS: The metabolic profile was attenuated in DM + siRNA vs. DM and there was a significant improvement in creatinine, urea and proteinuria levels in the same group. Renin expression was significantly decreased in DM + siRNA vs. DM. ACE and ACE2 were significantly reduced in DM + siRNA vs. DM. TBARS levels were decreased and NO showed an increase in DM + siRNA vs. DM, both significant. All histological alterations were improved in DM + siRNA vs. DM. SIGNIFICANCE: Data have shown that although silencing of the P2X7 receptor did not decrease fasting glucose, it promoted an improvement in the metabolic profile and a significant recovery of renal function, revealing a protective action by the inhibition of this receptor. This effect must have occurred due to the inhibition of RAS and the increase of NO, suggesting that the use of P2X7 receptors inhibitors could be used as adjuvant therapy against DN progression.

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BACKGROUND: Bulls are of great importance in the productive chain and for this reason they should have a good semen quality. There is no doubt that sperm morphology is very important to bull fertility, although little is known about how exactly the abnormal morphologies may affect sperm functions. OBJECTIVES: To detail the morphological description of the aplastic midpiece defect (AMD), as well as to understand its consequences for male fertility based on membrane and acrosome status, mitochondrial membrane potential and DNA integrity parameters. MATERIALS AND METHODS: The bulls were divided into two groups: control, consisting of satisfactory potential breeders (n = 3); and AMD, consisting of unsatisfactory potential breeders with a high percentage of AMD (n = 3). Bulls were evaluated by the breeding soundness evaluation; five ejaculates were collected from each animal and analyzed by flow cytometry. RESULTS: Spermatozoa from AMD group exhibited lower sperm motility and vigor (p < 0.05). In addition, it also exhibited lower mitochondrial membrane potential (p < 0.05), a higher percentage of spermatozoa with DNA fragmentation (p < 0.05), lower acrosome and plasma membrane integrity (p < 0.05), and higher lipid bilayer sperm membrane disorganization (p < 0.05) in comparison with control bulls. DISCUSSION: These findings may be due to oxidative stress and a reduction of the energy production capacity in addition to an alteration in the structural composition of the sperm cell. Moreover, semen with a high percentage of AMD may also be undergoing apoptosis. CONCLUSION: Bulls with a high percentage of AMD in their semen are not suitable for reproduction. Furthermore, it suggests there is a putative genetic basis for this sperm defect.

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Abstract Aquatic macrophytes have a recognized role in ecosystem structuring and an important position in trophic cascades interactions, whose understanding is to improve water quality. In recent years, the number of studies on the role of aquatic macrophytes in trophic webs and interactions has increased, but South America has made little progress in research in the area. In this study, we investigated the main gaps and perspectives for future studies on macrophytes and trophic interactions, analyzing global publications, especially those conducted by South American researchers. We accessed publications using an international database (Thomson Reuters ISI-Web of Knowledge-(formerly Institute for Scientific Information)) from 1980 to 2015. We ranked each article by ecosystem and study approach, biological organization and interacting taxonomic groups (phytoplankton, periphyton, zooplankton, aquatic invertebrates, fish and birds), countries publishing in cooperation and affiliations. The results showed that published studies (n = 242) emphasizing aquatic plants in trophic interactions increased in 35 years. Comparing the contributions of the 32 countries investigated, those from South America as first affiliation, had few publications (n = 26) and in cooperation (n = 7). The largest volume of articles indexed by the researchers dealt with the dynamics and structure of aquatic assemblages, webs and trophic interactions. Ecosystems such reservoirs and wetlands have received little attention. Large numbers of studies have encompassed community-wide aquatic approaches, including in South American studies, the interactions between macrophytes, zooplankton and phytoplankton were the second most studied interactions of all indexed articles. Knowledge about trophic cascade and interactions has been successfully enhanced in several countries with the purpose of restructuring communities and restore water quality of many ecosystems. In summary, we conclude that studies in the area of trophic interactions mediated by macrophytes may be directed in a way to attenuate international asymmetries, encouraging the increase of scientific productivity in South America.

Resumo Macrófitas aquáticas tem reconhecida função na estruturação de ecossistemas e importante papel nas interações tróficas em cascata, cujo entendimento é chave para melhorar a qualidade da água. Nos últimos anos, o número de estudos sobre o papel das macrófitas aquáticas nas interações e teia trófica aumentaram mas, a América do Sul progrediu pouco em pesquisas na área. Nesse estudo investigamos as principais lacunas e perspectivas para estudos futuros sobre macrófitas e interações tróficas analisando publicações mundiais, especialmente aquelas conduzidas por pesquisadores sul-americanos. Acessamos publicações usando base de dados internacional (Thomson Reuters ISI Web of Knowledge) entre 1980 a 2015. Computamos para cada artigo a organização biológica e grupos taxonômicos em interação (fitoplâncton, perifíton, zooplâncton, invertebrados aquáticos, peixes e aves), ecossistema estudado e abordagem de pesquisa, a cooperação entre países da América do Sul e demais, além das filiações. Os resultados mostraram que estudos publicados (n = 242) enfatizando plantas aquáticas em interações tróficas cresceram em 35 anos. Comparando as contribuições dos 32 países investigados, aqueles da América do Sul apresentaram baixo número de indexações (n= 26), poucos em cooperação (n= 7). O maior volume de publicações indexadas pelos pesquisadores trataram sobre a dinâmica e estrutura das assembléias aquáticas, teias e interações tróficas. Reservatórios e áreas alagadas têm recebido pouca atenção. Grande número de estudos compreeenderam abordagems de toda comunidade aquática e interações entre macrófitas, fitoplâncton, zooplâncton e peixes. Em síntese, concluimos que estudos enfatizando as interações tróficas mediadas pelas macrófitas poderão ser direcionados de maneira a atenuar assimetrias internacionais, encorajando o aumento da produtividade científica na América do Sul. O conhecimento sobre as interações tróficas em cascata tem sido desenvolvido com sucesso em diversos países cujas finalidades tem sido reestruturar comunidades e restaurar a qualidade da água de muitos ecossistemas.

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BACKGROUND: Envenomation caused by Bothrops alternatus is common in Southern Brazil. Acute Kidney Injury occurs after Bothrops snakebite and more information is necessaryrequired to understand its mechanism. OBJECTIVE: The objective was to evaluate the effect of Bothrops alternatus venom (BaV) on renal cells and rat isolated kidney function. METHODS: Wistar rats (n = 6, weighing 260-320 g) were perfused with a Krebs-Henseleit solution containing 6 g 100 mL-1 of bovine serum albumin. After 30 minutes, the kidneys were perfused with BaV to a final concentration of 1 and 3 µgmL-1; and subsequently were evaluated for Perfusion Pressure (PP), Renal Vascular Resistance (RVR), Urinary Flow (UF), Glomerular Filtration Rate (GFR), and percentage of electrolyte tubular transport. Renal histological analysis, cytokine release, oxidative stress and cytotoxicity in renal proximal tubular cells were assessed. RESULTS: BaV reduced PP, RVR, GFR, UF, total and proximal sodium transport (%TNa+), and chloride (%TCl-) in the isolated kidney perfusion model. Histological analysis of perfused kidneys disclosed the presence of proteinaceous material in the glomeruli and renal tubules, vacuolar tubular epithelial cell degeneration, Bowman's capsule degeneration, swelling of glomerular epithelial cells, glomerular atrophy and degeneration, and the presence of intratubular protein. Cytokine release (TNF-α, IL-1ß, IL-10) and oxidative stress were increased in the kidneys. The viability of LLC-MK2 cells (IC50: 221.3 µg/mL) was decreased by BaV and necrosis was involved in cell death. CONCLUSION: These findings indicate that BaV modifies functional parameters in an isolated perfused kidney model and has cytotoxic effects on renal lineage cells.

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