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Background and Aims: Recent evidence suggests that the mesenteric adipose tissue (MAT) near the affected intestine may play a role in Crohn's disease (CD) pathophysiology. Modulation of several transcripts has already been identified in the MAT of CD in the literature. Therefore, our aim was to validate the microRNA (miRNA) transcript levels and their target genes in the MAT of active CD patients and correlate them with clinical and epidemiological data. Methods: Samples from the MAT of surgical specimens from 25 active CD patients were obtained. The control group comprised fifteen patients who underwent surgery for other diseases, except inflammatory bowel diseases. Transcriptional levels of miRNA and their target genes were assessed by quantitative real-time polymerase chain reaction. The correlation between transcripts and clinical characteristics was obtained using multiple linear regression. The mathematical models (M) underwent a statistical filter to ensure robustness and reliability (P value < .05; adjusted R-squared (Rˆ2)> .99; correct predictions of more than 60%). Results: miRNA-650 and miRNA-29c were upregulated in the MAT of CD compared to the control group (P < .0001 and P = .0032, respectively), besides presenting decreased levels of their target genes. Two were target genes of the miRNA-650: glutamine-fructose-6-phosphate transaminase 2 (P = .012) and aldehyde dehydrogenase 4 family (P = .0035); and 4 were targets of the miRNA-29c: cell death-inducing DFFA-like effector c (P = .001), E2F transcription factor-1 (P = .007), hypoxia-inducible factor 3 subunit alpha (P = .0029), and pyruvate dehydrogenase kinase 4 (P = .0054). We found 2 M with statistical strength and robustness. The performance test identified one model with 100% accuracy for predicting the month of recurrence and determining patients with less risk of early relapse after surgery. Conclusion: We demonstrate that miRNA-650 and miRNA-29c and some of their target genes, besides clinical and epidemiological variables, may be useful in a model to predict when disease relapse may occur in CD patients who underwent surgery. These findings constitute a potential tool to guide postoperative clinical management.

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BACKGROUND: Although the gastrointestinal tract is the most affected by Crohn's disease (CD), the condition triggers other consequent manifestations, and iron deficiency anemia (IDA) is one of the most common. Intravenous (IV) iron replacement is currently available through several drugs, such as ferric hydroxide sucrose and ferric carboxymaltose (FCM). However, the clinical management of these conditions can be challenging. AIM: To elucidate the drug's effectiveness, the present study analyzed, through medical records, the clinical and epidemiological data of a cohort of patients with active CD who received IV FCM for the IDA treatment. METHODS: This retrospective observational study included 25 patients with active CD, severe anemia, and refractory to previous conventional treatments. Patients were evaluated two times: During the last treatment with ferric hydroxide sucrose and treatment with FCM. RESULTS: After treatment with FCM, parameters of IDA assessment significantly improved, serum hemoglobin (Hb) levels increased in 93% of patients (P < 0.0001), and in 44%, there was an increase of ≥ 2 g/dL in a single application. In addition, 86% of the patients showed an increase in serum iron (P < 0.0001) and ferritin (P = 0.0008) and 50% in transferrin saturation (P = 0.01). The serum iron levels at baseline showed a negative association with the ileal and colonic CD and use of biologics and a positive association with patients who developed CD later in life after the age of 40 (A3) and with a stenosing (B2) and fistulizing (B3) phenotype. The values of Hb and hematocrit after ferric hydroxide sucrose treatment remained similar to those found before treatment. CONCLUSION: This study demonstrated that FCM is an important therapeutic strategy for treating IDA in CD patients, achieving satisfactory results in refractory cases.

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INTRODUCTION: Crohn's disease (CD) is an inflammatory bowel disease (IBD) that affects the gastrointestinal tract and can have a major impact on the patient's quality of life and social/professional activities. Asymptomatic patients, or those with mild symptoms, experience the active disease with subclinical manifestation. Systematic review (SR) was performed to look for evidence for the role of chemokines and adipokines as markers for CD activity. METHODS: This SR was conducted by searching published studies in international and regional databases up till July, 2020. CD patients were adults with the disease in activity or remission. All adipokines and chemokines were considered for the analysis and the Rayyan QCRI system was used. RESULTS: In total, 20 studies were included. Six addressed chemokines and eight adipokines as potential biomarkers of CD activity. CXCL8 was the most studied chemokine (8 studies) and the results were controversial, with 62.5% showing a significant association with CD activity. CXCL10 was investigated by 4 studies and 50% identified it as a potential biomarker. CCL2, CCL11, CCL26 and CXCL1 were examined by 2 articles each. CXCL8 (P=0.002/P=0.001) and CXCL1 (P<0.001) presented the lowest? P value, which qualifies them as potential markers of disease activity. All the adipokines were tested in peripheral blood but 44.4% were also tested in intestinal mucosa, while the percentage in the chemokines' studies was 76.9% in peripheral blood, 46.1% in intestinal mucosa and 7.6% in urine sample respectively. CONCLUSION: The development of disease activity biomarkers for CD is becoming relevant for clinical practice. Chemokines and adipokines have the potential to signalize CD activity, but validation in larger cohorts of patients, preferable multicenter studies are still needed.

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PURPOSE: This study aimed to compare the three-dimensional volumetric changes of human maxillary sinuses after reconstruction using 5 different bone grafts. PATIENTS AND METHODS: Patients underwent unilateral maxillary sinus bone height reconstruction using 5 bone substitutes allocated in different groups as follows: group 1 was grafted with autogenous bone graft alone; group 2 with beta-tricalcium phosphate (ß-TCP); group 3 with ß-TCP + autogenous bone graft 1:1; group 4 with bioactive glass; and group 5 with bioactive glass + autogenous bone graft 1:1. The patients were submitted to cone beam computed tomography in two periods: 15 days after the surgical procedure (T1) and after 6 months (T2). The results were evaluated as the formula T2-T1 expressing the three-volumetric changes of the biomaterials in elapsed time. RESULTS: The resorption rate of autogenous bone graft was -630.699 ± 300.9 mm3; in the ß-TCP group, it was -315.772 ± 125.6 mm3; in the group with ß-TCP + autogenous bone graft 1:1, it was -336.205 ± 195.7 mm3; and in groups with bioactive glass and with the addition of autogenous bone graft 1:1, it was -428.878 ± 311.6 mm3 and -576.917 ± 471.6 mm3, respectively, without statistical difference (p = 0.167). Pearson's correlated test revealed a strong correlation as well as a progressive resorption of the grafts during bone healing. CONCLUSION: The similar outcomes for the three-dimensional volumetric changes using the bone substitutes evaluated after 6 months of bone healing suggest that all these grafts can be performed to maxillary sinus reconstruction.

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BACKGROUND: Crohn's disease (CD) is an inflammatory bowel disease (IBD) that can affect the entire gastrointestinal tract and can have a major impact on the patient's quality of life. Asymptomatic patients, or those with mild symptoms, experience the active disease with subclinical manifestation. A systematic review (SR) was performed to look for evidence for the role of chemokines and adipokines as markers for CD activity. METHODS: This SR was conducted by searching published studies in international and regional databases up to July 2020. CD patients were adults with the disease in activity or remission. All adipokines and chemokines were considered for the analysis and the Rayyan QCRI system was used. The selection of articles published in the Rayyan system was carried out by two reviewers, autonomously and independently, and a third reviewer was responsible for analysing and deciding on the inclusion or exclusion of the article, especially in relation to those who presented a contradictory and conflicting decision. The search for articles was carried out in the databases PUBMED, PUBMED PM C, BVSBIREME, SCOPUS, WEB OF SCIENCE, EMBASE, COCHRANE, EBSCOHOST, PROQUEST and ENDNOTE WEB. The keywords "Crohn's disease", "chemokines", "adipokines", "biomarkers" and "inflammation" were chosen after reading material related to the researched topic. To expand and guide the search, an association of the descriptors was carried out by means of Boolean operators "OR" and "AND". The Boolean operators "OR" and "AND" were used to add or restrict the search, as follows: "Crohn Disease AND Biomarkers AND (Chemokines OR Adipokines) AND Inflammation". Only studies with human samples were considered. RESULTS: In total, 20 studies were included from 344 which were found in the databases. Six addressed chemokines and eight adipokines as potential biomarkers of CD activity. CXCL8 was the most studied chemokine (8 studies) and the results were controversial, with 62.5% showing a significant association with CD activity. CXCL10 was investigated by 4 studies and 50% identified it as a potential biomarker. CCL2, CCL11, CCL26 and CXCL1 were examined by 2 articles each. CXCL8 (P=0.002/P=0.001) and CXCL1 (P < 0.001) presented the lowest P value, which qualifies them as potential markers of disease activity. All the adipokines were tested in peripheral blood but 44.4% were also tested in intestinal mucosa, while the percentage in the chemokines' studies was 76.9% in peripheral blood, 46.1% in intestinal mucosa and 7.6% in urine sample respectively. CONCLUSION: Despite the limitations and the small number of studies found in the literature that followed the criteria of this SR, some chemokines (CCL2, CCL20, CXCL1, CXCL3, CXCL8, CXCL10 and CXCL1) and adipokines (leptin, IL-6 and TNF-α) have unveiled promising results that may enable us to distinguish active versus in remission forms of CD based on objective criteria of inflammation such as endoscopic, histologic or radiological criteria. The development of disease activity biomarkers for CD is becoming relevant for clinical practice, and chemokines and adipokines have the potential to signalize CD activity. However, validation in larger cohorts of patients, preferable multicenter studies are still needed.

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Nos últimos 30 anos, o Brasil consolidou aspectos da mudança estrutural no mercado de trabalho referentes à modernização ocupacional, participação feminina e expansão do ensino superior. Nesse sentido, coortes mais jovens se inserem em um contexto distinto daqueles presenciados em décadas passadas. Logo, este artigo tem como objetivo medir a variação da segregação ocupacional e a disparidade salarial por gênero e raça em três grupos etários. Assim, questiona-se: a segregação ocupacional por gênero e raça é menor entre os mais jovens? Isso se reflete em menor desigualdade salarial? Tais perguntas são analisadas por meio de índices de segregação e decomposições salariais com base na PNAD 2015 para uma amostra de pessoas com ensino superior completo. Os resultados apontam menor desigualdade entre os mais jovens, mas ainda deixam dúvidas se são efeitos de idade ou coorte. Para isso, uma segunda análise compara os índices de segregação da coorte entre 26 e 35 anos em 2015 com o mesmo intervalo nos anos de 1995 e 2005, com o intuito de separar os efeitos de coorte e de idade. Ao final, indica-se que a idade é mais associada ao aumento da desigualdade do que a coorte, embora entre os mais jovens haja menor segregação por raça.

In the past 30 years, Brazil strengthened labor market structural change on aspects related to occupational modernization, feminine participation and Higher Education expansion. In this regard, younger cohorts entered in a different context than those who entered in past decades. Thus, this research aims to measure occupational segregation and wage disparities by gender and race over three age groups. Therefore, the questions are: Is occupational segregation lower among younger people? Does it reflect on lower wage inequality? These questions are analyzed through segregation and wage decomposition from PNAD 2015 on a sample for people with Higher Education. These results point out to lower inequality among the youngest people, but doubts remain as to whether these are age or cohort effects. In this regard, the segregation index for the cohort between 26 and 35 years old in 2015 is compared to the same age range in 1995 and 2005, focusing on isolated cohort and age effects. In the end, it is pointed out that age is more associated with increasing inequality than with cohort, although segregation by race is lower among the younger cohort.

En los últimos treinta años, Brasil ha consolidado aspectos de cambio estructural en el mercado laboral relacionados con la modernización ocupacional, la participación femenina y la expansión de la educación superior. En este sentido, las cohortes más jóvenes se insertan en un contexto diferente del que se insertaron en décadas pasadas. Por tanto, la presente investigación tiene como objetivo medir la variación en la segregación ocupacional y la brecha salarial por género y raza en tres grupos de edad. En este sentido, las preguntas son: ¿La segregación ocupacional por género y raza es menor entre las personas más jóvenes? ¿Se refleja esto en una menor desigualdad salarial? Estas preguntas se analizan mediante índices de segregación y descomposiciones del salario basados en el PNAD de 2015 en una muestra de personas con estudios superiores completos. Los resultados muestran tasas más bajas de desigualdad entre las personas más jóvenes, pero aún dejan dudas sobre si son efectos de la edad o la cohorte. Para esto, las tasas de segregación de la cohorte de entre 26 y 35 años en 2015 se comparan con el mismo intervalo en los años 1995 y 2005, para separar los efectos de cohorte y edad. Al final, se indica que la edad está más asociada con una mayor desigualdad que la cohorte, aunque entre las personas más jóvenes hay menos segregación por raza.

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Este estudo teve como objetivo analisar o processo de formação óssea, bem como a microarquitetura óssea promovido pela associação entre o BioGran® e diferentes concentrações de raloxifeno através do método da sonoquímica em defeitos críticos realizados em calvária de rato. Em um total de doze ratos machos, um defeito crítico de 5 mm de diâmetro foi feito e preenchido com BioGran® 100% (Bg), BioGran® 90% associado à Raloxifeno 10%, e BioGran® 80% associado à Raloxifeno 20%. Aos 14 e 24 dias pós-operatório, foram aplicados os fluorocromos calceína e alizarina, de modo respectivo. A eutanásia ocorreu aos 30 dias após a realização do procedimento cirúrgico para enxertia dos biomateriais. Análise de microtomografia computadorizada (micro-CT) através dos parâmetros de superfiície de intersecção (i.S), fração de volume ósseo (BV/TV) e densidade de conectividade (Conn.Dn) e por microscopia confocal a laser por meio da dinâmica óssea, superfície de mineralização ativa e a taxa de aposição mineral (MAR). Os dados foram analisados através de análise estatística utilizando o teste de normalidade Shapiro-Wilk e o pós teste de Turkey (p<0.05). Para os parâmetros de micro-CT avaliados os menores valores foram encontrados no grupo BG+RL10% (p<0,05), valores similares foram encontrados entre os grupos BG e BG+RL20%. A microscopia confocal evidenciou melhor mineralização óssea e maior taxa de aposição mineral (MAR) para o Grupo BG+RL20% (p<0,05%). Conclusão: A concentração de Raloxifeno a 20% combinado ao BioGran® pelo método da sonoquímica parece ter acelerado o reparo ósseo(AU)

This study aimed to analyze the bone formation process, as well as the bone microarchitecture promoted by the association between BioGran® and different concentrations of raloxifene through the sonochemistry method in critical defects performed in rat calvaria. In a total of twelve male rats, a critical defect of 5 mm in diameter was made and filled with BioGran® 100% (Bg), BioGran® 90% associated with Raloxifene 10%, and BioGran® 80% associated with Raloxifene 20%. At 14 and 24 days postoperatively, the fluorochromes calcein and alizarin were applied, respectively. Euthanasia occurred 30 days after the surgical procedure for grafting biomaterials. Analysis of computed microtomography (microCT) through the parameters of intersection surface (iS), bone volume fraction (BV / TV) and connectivity density (Conn.Dn) and by confocal microscopy through bone dynamics, surface of active mineralization and the mineral apposition rate (MAR). Data were analyzed through statistical using the Shapiro-Wilk normality test and the Turkey post-test (p <0.05). For the me microCT parameters evaluated, the lowest values were found in the BG + RL10% group (p<0.05), similar values were found between the BG and BG + RL20% groups. Confocal microscopy showed better bone mineralization and higher mineral apposition rate (MAR) for the BG + RL20% Group (p < 0.05%). Conclusion: The concentration of Raloxifene at 20% combined with BioGran® by the sonochemistry method seems to have accelerated bone repair(AU)

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As fraturas de mandíbula são as mais comuns no campo da Cirurgia e Traumatologia Bucomaxilofacial. Acometem cerca de 42,5% dentre os traumas faciais. O método a ser escolhido para o tratamento depende de diversos fatores, como o deslocamento e a cominuição dos fragmentos ósseos, a presença de má oclusão, a ação muscular local, a idade do paciente e a habilidade do cirurgião. Este trabalho tem por objetivo relatar um caso de fratura bilateral de mandíbula em corpo esquerdo e ângulo direito, tratado através de fixação interna rígida e técnica de Champy. Esta abordagem mostrou-se eficaz e segura neste tratamento, além de evitar cicatrizes antiestéticas e lesões às estruturas adjacentes. Um resultado pós-operatório de 3 meses é apresentado (AU).

Mandibular fractures are the most common in the field of Buccomaxillofacial Surgery and Traumatology. The prevalence rate is about 42.5% of facial traumas. The method of choice for the treatment depends on several factors, such as displacement and comminution of the bone fragments, presence of malocclusion, local muscular action, the age of the patient and the surgeon's skill. This paper aims to report a case of bilateral mandibular fracture in the left body and right angle treated through rigid internal fixation and the Champy technique. This approach proved to be effective and safe in this treatment, besides avoiding unsightly scars and lesions on adjacent structures. A 3-month postoperative result is presented (AU).

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O estudo da dor e suas particularidades é de grande importância para o tratamento de diversas patologias e para a melhora na qualidade de vida dos pacientes. A maioria das disfunções orgânicas tem a dor como um ponto importante da sua manifestação. Dessa maneira, é justificável a elaboração de conteúdo para auxiliar os profissionais da saúde no entendimento e tratamento das principais causas de dores agudas e crônicas. Este livro foi elaborado com o objetivo de servir como um guia prático para o manejo da dor por profissionais e acadêmicos de Medicina. Engloba temas como conceitos e aspectos biopsicossociais da dor, além de questões mais complexas como a fisiologia da dor e o tratamento medicamentoso com o arsenal terapêutico existente. Finalmente, também trata dos diversos tipos de dor mais prevalentes e o conhecimento básico que envolve seu manejo.

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A proximidade do ser humano tanto com animais domésticos quanto com silvestres, aumenta a probabilidade de transmissão de doenças zoonóticas. Dentro deste contexto, podemos destacar a relação entre o homem e as aves. Visto que as zoonoses bacterianas apresentam alto impacto na saúde pública, a necessidade de se conhecer os principais fatores de risco envolvidos na transmissão das bactérias aos humanos é de extrema importância. Com isso, essa revisão bibliográfica tem por finalidade contemplar as principais doenças bacterianas de aves tanto domésticas quanto silvestres as quais apresentam caráter zoonótico.(AU)

The proximity of humans with domestic or wild animals increases the probability oftransmission of zoonotic diseases. Within this context, we highlight the relationship between manand birds. Since bacterial diseases have a high impact on public health, the need to know the mainrisk factors involved in the transmission of bacteria to humans is extremely important. Thus, thisreview is intended to include the major zoonotic bacterial diseases of domestic and wild birds.(AU)

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A proximidade do ser humano tanto com animais domésticos quanto com silvestres, aumenta a probabilidade de transmissão de doenças zoonóticas. Dentro deste contexto, podemos destacar a relação entre o homem e as aves. Visto que as zoonoses bacterianas apresentam alto impacto na saúde pública, a necessidade de se conhecer os principais fatores de risco envolvidos na transmissão das bactérias aos humanos é de extrema importância. Com isso, essa revisão bibliográfica tem por finalidade contemplar as principais doenças bacterianas de aves tanto domésticas quanto silvestres as quais apresentam caráter zoonótico.

The proximity of humans with domestic or wild animals increases the probability oftransmission of zoonotic diseases. Within this context, we highlight the relationship between manand birds. Since bacterial diseases have a high impact on public health, the need to know the mainrisk factors involved in the transmission of bacteria to humans is extremely important. Thus, thisreview is intended to include the major zoonotic bacterial diseases of domestic and wild birds.

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This study assessed the desiccation effects on biomass and algal density of periphyton in a subtropical lentic ecosystem. This experiment was conducted with only one in situ experimental desiccation event for 15 hours in a mature periphytic community. The periphyton after desiccation was distinct in density and biomass estimators (dry weight and chlorophyll a) when compared to the control periphyton. After the tenth day of desiccation, the community presented similar values for biomass estimators when compared to the control periphyton. The density and biomass estimators of the periphyton community was affected by the desiccation event and required about ten days to recover to pre-disturbance conditions.(AU)

Este estudo avaliou os efeitos do dessecamento sobre a biomassa e a densidade algal do perifíton em ecossistema lêntico subtropical. Neste experimento foi realizado um evento in situ de 15h de emersão sobre a comunidade perifítica em estágio maduro de desenvolvimento. O perifíton sujeito ao dessecamento foi distinto na densidade e nos estimadores de biomassa (peso seco e clorofila) em relação ao perifíton controle. Após do décimo dia de dessecamento, a comunidade apresentou valores similares dos estimadores de biomassa quando comparado com o perifíton controle. A densidade e os estimadores de biomassa da comunidade perifítica foram afetadas pelo evento de dessecamento e requereu dez dias para retornar as condições de pré-distúrbio.(AU)

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This study assessed the desiccation effects on biomass and algal density of periphyton in a subtropical lentic ecosystem. This experiment was conducted with only one in situ experimental desiccation event for 15 hours in a mature periphytic community. The periphyton after desiccation was distinct in density and biomass estimators (dry weight and chlorophyll a ) when compared to the control periphyton. After the tenth day of desiccation, the community presented similar values for biomass estimators when compared to the control periphyton. The density and biomass estimators of the periphyton community was affected by the desiccation event and required about ten days to recover to pre-disturbance conditions.

Este estudo avaliou os efeitos do dessecamento sobre a biomassa e a densidade algal do perifíton em ecossistema lêntico subtropical. Neste experimento foi realizado um evento in situ de 15h de emersão sobre a comunidade perifítica em estágio maduro de desenvolvimento. O perifíton sujeito ao dessecamento foi distinto na densidade e nos estimadores de biomassa (peso seco e clorofila) em relação ao perifíton controle. Após do décimo dia de dessecamento, a comunidade apresentou valores similares dos estimadores de biomassa quando comparado com o perifíton controle. A densidade e os estimadores de biomassa da comunidade perifítica foram afetadas pelo evento de dessecamento e requereu dez dias para retornar as condições de pré-distúrbio.

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The aim of this study was to evaluate the biomass of the periphytic community in aquaculture net cages of Oreochromis niloticus. We determined the time required to stabilize this community and contributed to the knowledge of its potential to sustain the fish production. For this, 15 net cages were set in an arm of the Rosana Reservoir (Paranapanema River), the Corvo River. In these net cages, artificial substrates were used to allow the development of the periphytic community, which had its biomass monitored fortnightly, indexed as chlorophyll-a, dry weight, ash-free dry weight and percentage of ash. The biomass of periphytic community found in the net cages of the Corvo River was high. In fact, it was higher than the values already reported by other authors in a variety of cultivation systems. Considering chlorophyll-a, the time for the community be considered mature, with uniform pattern of colonization and maximum concentration was four weeks. The knowledge of this time, necessary for the stabilization of the periphytic community, is of great importance to aquaculture. The use of this community as natural food may contribute to the sustainable management of systems and reduce costs for the producer, with reduction of the use of commercial food, for the environment with less addition of nutrients.

O objetivo deste trabalho foi avaliar a biomassa da comunidade perifítica em tanques-rede de criação de Oreochromis niloticus, verificando o tempo necessário para a estabilização desta comunidade, bem como contribuir para o conhecimento do seu potencial em dar suporte à produção de peixes. Para isto, 15 tanques-rede foram instalados na área de remanso do rio do Corvo, afluente do rio Paranapanema, cujas águas foram represadas para a formação do reservatório de Rosana. Nesses tanques, substratos artificiais foram utilizados para o desenvolvimento da comunidade perifítica, que teve sua biomassa medida quinzenalmente por meio de clorofila-a, peso seco, peso seco livre de cinzas e porcentagem de cinzas. A biomassa perifítica encontrada nos tanques-rede do rio do Corvo foi elevada, superior ao já registrado por outros autores em uma variedade de sistemas de cultivo. Em termos de clorofila-a, o tempo necessário para a comunidade ser considerada madura, com padrão uniforme de colonização e máxima concentração, foi de quatro semanas. O conhecimento deste tempo, necessário para a estabilização da comunidade perifítica, é de grande importância para a aquicultura. A utilização desta comunidade como alimento natural pode contribuir para o manejo sustentável dos sistemas, bem como para diminuir os custos para o produtor, com a redução de ração comercial, e para a melhoria do ambiente, pela

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This study aimed to analyze the richness and abundance of periphytic algae in Corvo and Guairacá rivers, both tributaries of the Rosana reservoir. It was believed that the site just ahead of the installation of net cages presented less richness and abundance of algae. For this, samples were collected 500 and 1,000 m upstream, and downstream and in front of the net cage. Regardless the environment influence, the station that recorded the highest number of species was the 1,000 m upstream. And those that recorded the lowest richness were 500 m upstream and downstream. In front of the tanks was the most abundant, followed by the 1,000 m downstream. On the other hand, the abundance on the 500 m stations was the lowest. Thus, regardless of the lotic environment, less richness and abundance of periphytic algae was found in stations 500 m from the cages, which reinforces the importance of carrying out biomonitoring in an area of greater coverage.

Este trabalho objetivou analisar a riqueza e a abundância de algas perifíticas nos rios do Corvo e Guairacá, tributários do reservatório de Rosana, quando da instalação de tanques-rede. Acreditava-se que o ponto logo à frente dos tanques-rede apresentaria menor riqueza e abundância de algas e que o reservatório influenciaria as estações a jusante dos tanques. Para isso, coletas foram realizadas a montante, em frente e a jusante da instalação de tanques-rede. Independentemente do ambiente, a estação que apresentou maior riqueza foi 1.000 m a montante. Diminuição na riqueza foi verificada nas estações 500 m a montante e 500 m a jusante. Quanto à densidade, em frente aos tanques, observou-se maior abundância, seguida pela estação a 1.000 m a jusante. Já, nas estações de amostragem a 500 m (a montante e jusante), o número de indivíduos foi inferior às demais. Assim, independentemente do ambiente lótico, constatou-se menor riqueza e abundância de algas perifíticas nas estações a 500 m dos tanques, o que reforça a importância de ser realizado o biomonitoramento em uma área de maior abrangência.

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The aim of this study was to evaluate the biomass of the periphytic community in aquaculture net cages of Oreochromis niloticus. We determined the time required to stabilize this community and contributed to the knowledge of its potential to sustain the fish production. For this, 15 net cages were set in an arm of the Rosana Reservoir (Paranapanema River), the Corvo River. In these net cages, artificial substrates were used to allow the development of the periphytic community, which had its biomass monitored fortnightly, indexed as chlorophyll-a, dry weight, ash-free dry weight and percentage of ash. The biomass of periphytic community found in the net cages of the Corvo River was high. In fact, it was higher than the values already reported by other authors in a variety of cultivation systems. Considering chlorophyll-a, the time for the community be considered mature, with uniform pattern of colonization and maximum concentration was four weeks. The knowledge of this time, necessary for the stabilization of the periphytic community, is of great importance to aquaculture. The use of this community as natural food may contribute to the sustainable management of systems and reduce costs for the producer, with reduction of the use of commercial food, for the environment with less addition of nutrients.

O objetivo deste trabalho foi avaliar a biomassa da comunidade perifítica em tanques-rede de criação de Oreochromis niloticus, verificando o tempo necessário para a estabilização desta comunidade, bem como contribuir para o conhecimento do seu potencial em dar suporte à produção de peixes. Para isto, 15 tanques-rede foram instalados na área de remanso do rio do Corvo, afluente do rio Paranapanema, cujas águas foram represadas para a formação do reservatório de Rosana. Nesses tanques, substratos artificiais foram utilizados para o desenvolvimento da comunidade perifítica, que teve sua biomassa medida quinzenalmente por meio de clorofila-a, peso seco, peso seco livre de cinzas e porcentagem de cinzas. A biomassa perifítica encontrada nos tanques-rede do rio do Corvo foi elevada, superior ao já registrado por outros autores em uma variedade de sistemas de cultivo. Em termos de clorofila-a, o tempo necessário para a comunidade ser considerada madura, com padrão uniforme de colonização e máxima concentração, foi de quatro semanas. O conhecimento deste tempo, necessário para a estabilização da comunidade perifítica, é de grande importância para a aquicultura. A utilização desta comunidade como alimento natural pode contribuir para o manejo sustentável dos sistemas, bem como para diminuir os custos para o produtor, com a redução de ração comercial, e para a melhoria do ambiente, pela

RESUMO

This study aimed to analyze the richness and abundance of periphytic algae in Corvo and Guairacá rivers, both tributaries of the Rosana reservoir. It was believed that the site just ahead of the installation of net cages presented less richness and abundance of algae. For this, samples were collected 500 and 1,000 m upstream, and downstream and in front of the net cage. Regardless the environment influence, the station that recorded the highest number of species was the 1,000 m upstream. And those that recorded the lowest richness were 500 m upstream and downstream. In front of the tanks was the most abundant, followed by the 1,000 m downstream. On the other hand, the abundance on the 500 m stations was the lowest. Thus, regardless of the lotic environment, less richness and abundance of periphytic algae was found in stations 500 m from the cages, which reinforces the importance of carrying out biomonitoring in an area of greater coverage.

Este trabalho objetivou analisar a riqueza e a abundância de algas perifíticas nos rios do Corvo e Guairacá, tributários do reservatório de Rosana, quando da instalação de tanques-rede. Acreditava-se que o ponto logo à frente dos tanques-rede apresentaria menor riqueza e abundância de algas e que o reservatório influenciaria as estações a jusante dos tanques. Para isso, coletas foram realizadas a montante, em frente e a jusante da instalação de tanques-rede. Independentemente do ambiente, a estação que apresentou maior riqueza foi 1.000 m a montante. Diminuição na riqueza foi verificada nas estações 500 m a montante e 500 m a jusante. Quanto à densidade, em frente aos tanques, observou-se maior abundância, seguida pela estação a 1.000 m a jusante. Já, nas estações de amostragem a 500 m (a montante e jusante), o número de indivíduos foi inferior às demais. Assim, independentemente do ambiente lótico, constatou-se menor riqueza e abundância de algas perifíticas nas estações a 500 m dos tanques, o que reforça a importância de ser realizado o biomonitoramento em uma área de maior abrangência.