Daniel Lemos

Protein digestion in penaeid shrimp: digestive proteinases, proteinase inhibitors and feed digestibility

Protein is the most abundant ingredient in both natural and prepared diets of penaeid shrimp. The assessment of protein digestion through the developmental stages of penaeids may contribute to the development of more suitable feeding schedules for their cultivation. Among the techniques to study protein digestion, detection and characterization of digestive proteinase inhibitors in w proteinaceous feed ingredients can be achieved by substrate- sodium dodecyl sulphate polyacryl- x . amide gel electrophoresis SDS-PAGE . In vitro assays of protein digestibility are also useful tools when testing alternative protein sources in the formulation of shrimp feeds. The present . article reviews three methods that have been used to assess protein digestion: 1 detection and characterization of proteinase activity and proteinaceous proteinase inhibitors by substrate-SDS- . . PAGE, 2 quantification of proteinase activity, and 3 in vitro evaluation of digestibility of dietary protein sources by shrimp proteinases. A compilation of previously reported and unpub- lished data on some aspects of penaeid protein digestion is presented. Trypsin activity of Litopenaeus schmitti varied considerably during larval and postlarval development, showing the highest value at protozoea III. The molecular weight of digestive proteinases from early stages of Farfantepenaeus paulensisalso differed from the adult pattern, and some activity bands could be characterized as trypsin in adult F. paulensis. The digestive proteinase pattern of adult Farfante- penaeus californiensis, F. paulensis, L. schmitti and Litopenaeus ˝annamei in SDS-PAGE showed clear differences among these species, which may be evidence of a species-specific pattern of protein digestion. In vitro evaluation of digestibility of aquafeeds can be achieved by the pH-stat method, which can help in the choice for alternative protein sources. Moreover, the quality

Energy partitioning into growth, respiration, excretion and exuvia during larval development of the shrimp Farfantepenaeus paulensis

Abstract Energy channeled into growth (P), metabolism maintenance (R), excretion (E) and exuvia (Ev) were quantified in feeding larval stages of Farfantepenaeus paulensis reared under commercial practices at 26±1°C and 34±1‰ S. Dry weight, oxygen consumption, ammonia-N excretion and energy content were determined in protozoeal (PZ I–PZ III) and mysid (M I–M III) stages. In stages PZ III and M I, a higher weight increment (P) was observed compared to other larval stages. Energy expended in metabolism (R) increased through each subsequent stage, showing higher increment in the intervals PZ II–PZ III (1.7-fold) and PZ III–M I (1.8-fold). Losses by excretion (E) and exuvia (Ev) presented lower values compared to P and R. From the total energy assimilated between PZ I and M III, growth comprised 42% while metabolism 52%. The percentage of assimilated energy channeled into growth (net growth efficiency or K2) was ∼50% in PZ I and PZ II, reaching the highest value in PZ III (K2=69.9%). In the following stages, K2 remained between 33.3% and 49.8%. The metabolism (R) and growth (P) ratio showed higher growth investment in PZ III (R/P=44.9%) compared to other stages. PZ I and PZ III exhibited higher growth in relation to individual energy content (P/B>100%), while M II and M III presented lower results (P/B=12.8–18.6%). Energetics of larval development indicated a planktonic phase with intense swimming activity and high metabolic rate, ingestion and growth (PZ I–PZ III). The transition to a benthic existence was marked by decreased metabolic rate and growth (M I–M III). These energetic parameters may be used as condition indices for cultured larvae as they help to explain how hatchery practices may affect metabolism and growth of the organisms.

Ontogenetic variation in digestive proteinase activity, RNA and DNA content of larval and postlarval white shrimp Litopenaeus schmitti

Abstract Proteinase (endopeptidase), trypsin and chymotrypsin activities, RNA, and DNA contents were examined throughout the ontogenetic development of cultured Litopenaeus schmitti . Whole individuals from larval and postlarval stages, and adult hepatopancreas were homogenized and assayed for quantification of enzyme activity. Proteinase activity of different life stages was characterized by substrate-SDS-PAGE. Specific inhibitors for trypsin (TLCK) and serine proteinases (PMSF) were used to identify activity zones of these enzymes in gels. Nucleic acids were also quantified in larval and postlarval stages. Protein-specific activity of total proteinases and trypsin presented higher values in nauplius IV (N IV), protozoea I (PZ I), and PZ III, compared to the remaining stages, while chymotrypsin activity peaked in N IV and PZ III. Enzyme activity was lower in egg, early nauplius, mysis, and postlarval stages. Different proteinase patterns were observed in SDS-PAGE during ontogenetic development. Active bands of 15.5, 16.0, 19.9, 21.8, 24.0, 27.9, 30.3, 33.5, 35.5, 38.2, and 48.1 kDa were detected in the adult hepatopancreas. In the course of development, proteolytic activity was detected in N IV, and intense bands of 17.3, 19.9, and 20.9 kDa were found up to mysis (M III). A band at 38.2 kDa was present between N IV and M I, and between PL II and PL IV. Most bands were serine proteinases, and only two bands in adult (15.5 and 15.9 kDa) were inhibited by TLCK. Both RNA and DNA contents (μg mg −1 of fresh weight) reduced with development from egg to PZ III, increasing afterwards until PL IV. RNA/DNA ratios increased from egg, reaching a peak in PZ I, and decreased in the following stages until a minimum was reached in M II. A secondary peak was observed in PL III followed by reduction in PL IV. The variation in enzyme activity indicates different strategies of energy use throughout development. Higher enzyme activity combined with increased RNA/DNA in protozoeal stages denotes intense food energy use and accumulation into growth. The shift in energy strategy during the ontogeny of L. schmitti is accompanied by variation in proteinase characteristics as observed in other penaeid species.

Cobia (Rachycentron canadum): A Selected Annotated Bibliography on Aquaculture, General Biology and Fisheries 1967–2015

Abstract The good-quality white flesh of cobia (Rachycentron canadum) and high value in some markets make it one of the most important marine fish species for future aquaculture production. Commercial cobia farming from hatchery-produced seed stock began in the late 1990s and some aspects of broodstock management, larviculture, nutrition and health, among others, still need research and improvements. The present compilation covers the period between 1967 and 2015 and includes publications on cobia general biology, fisheries and aquaculture for the potential benefit of students, researchers, farmers, and the industry.

Avaliação a médio prazo do controle de fatores de risco de doença cardiovascular em coorte prospectiva de pacientes de alto risco tratados por intervenção coronária percutânea

INTRODUCAO: A prevencao secundaria apos intervencao coronaria percutânea (ICP) e fundamental para melhorar a sobrevida livre de eventos e consiste principalmente no controle de fatores de risco. Analisou-se a prevencao secundaria de pacientes de alto risco, incluidos prospectivamente no estudo Sequence Variation in Platelet Aggregation in Response to Clopidogrel and aspirin (SPARC). METODOS: Foram arrolados 187 pacientes consecutivos entre dezembro de 2009 e fevereiro de 2011, tratados por ICP com stent e avaliados em retornos ambulatoriais de 30 dias, 3 meses, 6 meses e 12 meses quanto ao controle de hipertensao arterial, disglicemia, dislipidemia e tabagismo, e medidas terapeuticas respectivas. RESULTADOS: Houve aumento significativo de pacientes com controle pressorico (29%; P = 0,02), que cessaram tabagismo (18%; P = 0,003), e que receberam hipolipemiantes (19%; P < 0,0001) entre a internacao para ICP e o primeiro retorno apos o procedimento. Esse melhora do controle de fatores de risco refletiu-se em reducao do escore de risco de Framingham medio observado no mesmo periodo (9,9%; P < 0,0001). Durante seguimento de ate 12 meses o ganho atingido na internacao para ICP se manteve para todos os fatores de risco. CONCLUSOES: Observou-se efeito importante relativamente a internacao indice para ICP, com aumento da prescricao de medicamentos para controle de fatores de risco e alcance de metas. Esse estudo identifica relevante janela de oportunidade para priorizacao do controle de fatores de risco na internacao inicial, quando ganhos expressivos sao observados e mantidos. Mas tambem explicita que esforcos adicionais sao necessarios para expandir o beneficio da prevencao secundaria no seguimento a medio prazo de pacientes tratados por ICP.

Uso do Sistema Manométrico Miniaturizado Pressure-Wire em Cardiopatias Estruturais Congênitas e Adquiridas

Background: Historically, intravascular pressure recording has contributed to the development of interventional cardiology. Although new imaging resources have gained much attention, accurate intravascular pressure measurement remains essential for the diagnosis and evaluation of interventional therapy methods. We describe the use of the miniature manometric system (pressure-wire) to obtain pressure curves in congenital and acquired structural heart diseases. Methods: The Radi Analyzer® Xpress (St. Jude Medical Inc., St. Paul, MN, USA) and PressureWire®Certus systems were used in procedures with 5 F catheters under eneral anesthesia and ventilatory support in children. Manometric tracings were obtained simultaneously from pressure-wire and the 5 F catheter in patients whose therapy strategies were dependent on the analysis of intravascular pressures, and in whom was not possible to obtain them accurately by conventional methods. Results: Pressure-wire was used to obtain pulmonary intravascular pressures in patients with systemic-pulmonary collaterals with or without angiographically detected stenosis, and with different structural heart diseases, in the evaluation of pulmonary branch stenosis, in the localization of surgical conduit stenosis (e.g. after Rastelli surgery), surgical shunts (such as Blalock-Taussig) and in the preoperative evaluation of cavo-pulmonary shunts. The procedure was performed safely, and manometric tracings were obtained with an adequate quality. Conclusions: The miniature manometric system is well accepted as a complementary diagnostic modality for the functional assessment of coronary lesions in interventional cardiology. It is also a complementary diagnostic method in different structural, congenital and acquired heart diseases.

Oclusão percutânea de comunicação interatrial tipo ostium secundum com prótese memopart

BACKGROUND: The authors report their initial experience with the Memopart™ device (Shanghai Shape Memory Alloy Co Ltd, Shanghai, China) for the occlusion of secundum atrial septal defect (ASD). METHODS: This was a prospective observational study of a series of patients undergoing percutaneous occlusion of ASD with right ventricle volume overload and favorable anatomic characteristics. The procedure was performed by percutaneous femoral approach. The mean follow-up was 10.3 ± 5 months, with clinical and 24-hour echocardiographic evaluations (or before hospital discharge), 1, 3, 6, and 12 months after implantation. RESULTS: From February/2012 to April/2013, 21 patients, 16 females, mean age 33.1 ± 18.7 years, were submitted to percutaneous occlusion of an ASD. The average diameter of the defect was 19.04 ± 6.25 mm and the device size was 21.42 ± 6.73 mm (8 to 34 mm). Total occlusion of the defect was observed in all cases before hospital discharge. During follow-up, all patients were asymptomatic and without residual shunt. There was no deaths or any other complications in the series. CONCLUSIONS: The percutaneous closure of ASD using a Memopart™ device is an effective and safe procedure within the limits of this investigation. The device is user-friendly and has a high rate of immediate occlusion, even in large defects.

Valvoplastia mitral pela técnica de inoue: registro do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo

INTRODUCAO: Apesar da alta prevalencia de estenose mitral no Brasil, nota-se impressionante subnotificacao dos procedimentos de tratamento percutâneo dessa afeccao na literatura nacional. Este artigo tem como objetivo relatar os resultados e a evolucao dos pacientes com estenose mitral reumatica, tratados pela tecnica de Inoue. METODOS: Foram analisados parâmetros clinicos, ecocardiograficos e relacionados ao procedimento de pacientes tratados no periodo de 1997 a 2009 e acompanhados por pelo menos um mes. RESULTADOS: Foram avaliados 102 pacientes, a maioria do sexo feminino (89,2%), com media de idade de 38,1 ± 11,1 anos, dos quais 80,4% estavam em classe funcional II-III. A area valvar media pela ecocardiografia (ECO) era de 1,01 ± 0,19 cm2 e pelo cateterismo (CAT), de 0,87 ± 0,2 cm2. O escore de Wilkins & Block estava entre 5 e 8 em cerca de 90% dos pacientes e 88,2% estavam em ritmo sinusal. O procedimento alcancou sucesso em 76,5% dos casos, com aumento da area valvar mitral media de 1,9 ± 0,5 cm2 pelo ECO (P < 0,001) e de 2 ± 0,5 cm2 pelo CAT (P < 0,001). O gradiente medio atrio esquerdo-ventriculo esquerdo reduziu-se de 16,6 mmHg para 4,2 mmHg (P < 0,001). O debito cardiaco aumentou de 3,75 l/min para 4,67 l/min (P < 0,001), sendo um preditor de sucesso para o procedimento. Em 79,4% dos pacientes obteve-se a evolucao de um ano, em que 87,6% dos pacientes estavam em classe funcional I e apenas 2 pacientes necessitaram tratamento cirurgico. Durante o seguimento de cinco anos nao foi observado nenhum caso de acidente vascular cerebral ou obito de causa cardiaca. CONCLUSOES: A valvoplastia mitral por tecnica de Inoue para o tratamento da estenose mitral reumatica e tecnica eficaz a medio prazo, e com baixa taxa de complicacoes.

Use of the pressure wire method for measuring pulmonary arterial pressures in patients with pulmonary atresia

OBJECTIVE The objective of the study was to analyse the use of the pressure wire for the acquisition of intravascular pulmonary pressures in the presence of pulmonary atresia and systemic-dependent pulmonary blood flow. METHODS In this study, we included patients with pulmonary atresia and systemic-dependent pulmonary circulation referred for diagnostic catheterisation for evaluation of pulmonary pressures during the period from April, 2012 to April, 2013. The systemic-pulmonary collateral arteries were selectively catheterised, and in the absence of a critical stenosis angiographically determined; the pressure wire was introduced in these arteries to reach the main pulmonary artery, and/or lobar, and segmental branches. Aortic and pulmonary pressures were simultaneously obtained. We evaluated the feasibility and safety of the method. RESULTS We studied 10 patients (age 21 days to 11 years). In all of them, the pressures of pulmonary circulation - main artery, and/or lobar, and segmental branches - were successfully measured with the pressure wire. Of eight patients with indication for Rastelli surgery, the pulmonary pressures were considered normal in five, and slightly increased in three. In two patients requiring univentricular correction - total cavopulmonary anastomosis - the diastolic pressure was increased (20 mmHg). All procedures were performed without haemodynamic instability, cardiac arrhythmia, systemic saturation reduction, death, or any other complication. CONCLUSION Measurement of pulmonary vascular pressures using the pressure wire in small patients with pulmonary atresia is safe and effective. It allows the acquisition of reliable pressure curves, even in the presence of small vessels, bending and tortuosity, without the risk usually associated with the use of conventional diagnostic catheters.

Base racional e plano de estudo prospectivo para avaliar o efeito de terapêutica antiplaquetária e vasodilatadora microcirculatória em pacientes com cardiopatia chagásica crônica e distúrbios microvasculares coronários

BACKGROUND: There is evidence based on experimental models studies in infections by Trypanosoma cruzi, as well as histopathologic studies in individuals with Chagas heart disease, suggesting that ischemia plays a role in the pathogenesis of myocardial lesions in the chronic phase of the disease. These ischemic disorders are caused by microcirculatory dysregulation. Atypical angina is a common symptom in patients in the chronic phase of Chagas heart disease. In a large number of patients, despite the absence of significant angiographic coronary obstructions, the occurrence of perfusion abnormalities is documented by myocardial scintigraphy during stress, which is reversible after rest. METHODS: This is a single center, prospective, single cohort study, with a therapeutic intervention, followed by a late quantitative reevaluation of the myocardial perfusion defects, initially detected in patients with Chagas heart disease and angiographically normal coronary arteries. Myocardial perfusion single-photon emission computed tomography (SPECT) will be performed before and 90 days after the therapeutic intervention, using sestamibi-Tc99m as a radiotracer and physical exercise or vasodilation stimulation with dipyridamole as stressors. Therapeutic intervention will consist of acetylsalicylic acid (single daily dose of 100 mg) associated to verapamil (80 mg bid and a total daily dose of 160 mg). The primary endpoint of the study is a reduction > 50% of the area of ischemic myocardium calculated by the polar scintigraphic map. CONCLUSIONS: This is the first study of a therapeutic approach to attenuate or revert ischemic myocardial perfusion abnormalities of microvascular origin in patients with chronic Chagas heart disease.