Design and optimization of an experimental maintenance system for yellow clam broodstock Amarilladesma mactroides (Reeve, 1854) / Desenvolvimento e otimização de um sistema de manutenção experimental para reprodutores de marisco branco Amarilladesma mactroides (Reeve, 1854)

The yellow clam is a sand-burrowing bivalve that inhabits the dissipative beaches from southern Brazil to the north coast of Argentina. In the last decades, populations of this species have been impacted by mass mortality events, overfishing and other anthropogenic activities. The production of juveniles in captivity would allow feasibility studies to be carried out to restore the natural stock as well as the production in aquaculture systems. Given the scarcity of studies on the maintenance of this species in captivity, a culture system and a management protocol were developed and tested. Wild-caught clams (total length ≥50 mm) were used in a series of 14 day-long trials. Survival was higher in clams that were allowed to bury into the sand. A permanent ink marker covered with a thin layer of a quick-hardening adhesive proved to be a reliable method to tag clams. The maintenance of yellow clams in this system resulted in high survival and growth, increases in the condition factor and oocyte diameter, and a relative advancement of gonadal development.

O marisco branco é um bivalve de areia que habita as praias dissipativas do sul do Brasil até a costa norte da Argentina. Nas últimas décadas, as populações desta espécie têm sido afetadas por eventos de mortalidade maciça, sobrepesca e outras atividades antropogênicas. A produção de juvenis em cativeiro permitiria a realização de estudos de viabilidade para restaurar o estoque natural, assim como a produção em sistemas de aquicultura. Dada a escassez de estudos sobre a manutenção desta espécie em cativeiro, um sistema de cultivo e um protocolo de manejo foram desenvolvidos e testados. Mariscos branco selvagens (comprimento total ≥50 mm) foram utilizados em uma série de ensaios de 14 dias de duração. A sobrevivência foi maior nos mariscos que podiam ser enterrados na areia. Um marcador de tinta permanente coberto com uma fina camada de adesivo de endurecimento rápido provou ser um método confiável para marcar os mariscos. A manutenção dos mariscos neste sistema resultou em alta sobrevivência e crescimento, aumento do fator de condição e do diâmetro do ovócito, e um relativo avanço do desenvolvimento gonadal.

Design and optimization of an experimental maintenance system for yellow clam broodstock Amarilladesma mactroides (Reeve, 1854)

Abstract The yellow clam is a sand-burrowing bivalve that inhabits the dissipative beaches from southern Brazil to the north coast of Argentina. In the last decades, populations of this species have been impacted by mass mortality events, overfishing and other anthropogenic activities. The production of juveniles in captivity would allow feasibility studies to be carried out to restore the natural stock as well as the production in aquaculture systems. Given the scarcity of studies on the maintenance of this species in captivity, a culture system and a management protocol were developed and tested. Wild-caught clams (total length 50 mm) were used in a series of 14 day-long trials. Survival was higher in clams that were allowed to bury into the sand. A permanent ink marker covered with a thin layer of a quick-hardening adhesive proved to be a reliable method to tag clams. The maintenance of yellow clams in this system resulted in high survival and growth, increases in the condition factor and oocyte diameter, and a relative advancement of gonadal development.

Resumo O marisco branco é um bivalve de areia que habita as praias dissipativas do sul do Brasil até a costa norte da Argentina. Nas últimas décadas, as populações desta espécie têm sido afetadas por eventos de mortalidade maciça, sobrepesca e outras atividades antropogênicas. A produção de juvenis em cativeiro permitiria a realização de estudos de viabilidade para restaurar o estoque natural, assim como a produção em sistemas de aquicultura. Dada a escassez de estudos sobre a manutenção desta espécie em cativeiro, um sistema de cultivo e um protocolo de manejo foram desenvolvidos e testados. Mariscos branco selvagens (comprimento total 50 mm) foram utilizados em uma série de ensaios de 14 dias de duração. A sobrevivência foi maior nos mariscos que podiam ser enterrados na areia. Um marcador de tinta permanente coberto com uma fina camada de adesivo de endurecimento rápido provou ser um método confiável para marcar os mariscos. A manutenção dos mariscos neste sistema resultou em alta sobrevivência e crescimento, aumento do fator de condição e do diâmetro do ovócito, e um relativo avanço do desenvolvimento gonadal.

Design and optimization of an experimental maintenance system for yellow clam broodstock Amarilladesma mactroides (Reeve, 1854) / Desenvolvimento e otimização de um sistema de manutenção experimental para reprodutores de marisco branco Amarilladesma mactroides (Reeve, 1854)

The yellow clam is a sand-burrowing bivalve that inhabits the dissipative beaches from southern Brazil to the north coast of Argentina. In the last decades, populations of this species have been impacted by mass mortality events, overfishing and other anthropogenic activities. The production of juveniles in captivity would allow feasibility studies to be carried out to restore the natural stock as well as the production in aquaculture systems. Given the scarcity of studies on the maintenance of this species in captivity, a culture system and a management protocol were developed and tested. Wild-caught clams (total length ≥50 mm) were used in a series of 14 day-long trials. Survival was higher in clams that were allowed to bury into the sand. A permanent ink marker covered with a thin layer of a quick-hardening adhesive proved to be a reliable method to tag clams. The maintenance of yellow clams in this system resulted in high survival and growth, increases in the condition factor and oocyte diameter, and a relative advancement of gonadal development.

O marisco branco é um bivalve de areia que habita as praias dissipativas do sul do Brasil até a costa norte da Argentina. Nas últimas décadas, as populações desta espécie têm sido afetadas por eventos de mortalidade maciça, sobrepesca e outras atividades antropogênicas. A produção de juvenis em cativeiro permitiria a realização de estudos de viabilidade para restaurar o estoque natural, assim como a produção em sistemas de aquicultura. Dada a escassez de estudos sobre a manutenção desta espécie em cativeiro, um sistema de cultivo e um protocolo de manejo foram desenvolvidos e testados. Mariscos branco selvagens (comprimento total ≥50 mm) foram utilizados em uma série de ensaios de 14 dias de duração. A sobrevivência foi maior nos mariscos que podiam ser enterrados na areia. Um marcador de tinta permanente coberto com uma fina camada de adesivo de endurecimento rápido provou ser um método confiável para marcar os mariscos. A manutenção dos mariscos neste sistema resultou em alta sobrevivência e crescimento, aumento do fator de condição e do diâmetro do ovócito, e um relativo avanço do desenvolvimento gonadal.

Is birth weight associated with pregestational maternal BMI? BRISA Cohort, Ribeirão Preto, Brazil

Given the increase of women with excess weight or obesity and its possible effects on birth weight, the present study aimed to investigate the association between pregestational maternal body mass index (BMI) and birth weight in a birth cohort from Ribeirão Preto, SP, Brazil. This was a prospective study conducted on 1362 mother-child pairs involving singleton births. The women were evaluated using standardized questionnaires during the second trimester of pregnancy and at the time of childbirth. Information about the newborns was obtained from their medical records. The dependent variable was birth weight, categorized as low, adequate, or high. The independent variable was pregestational maternal BMI, categorized as malnutrition, adequate weight, overweight, and obesity. A multinomial regression model was used to estimate the crude and adjusted relative risk (RR) of low and high birth weight. A high frequency of pregestational excess weight (39.6%) was detected and found to be independently associated with high birth weight (RR=2.13, 95%CI: 1.19-3.80 for overweight and RR=3.34, 95%CI: 1.80-6.19 for obese pregnant women). There was no association between pregestational malnutrition and low birth weight (RR=1.70; 95%CI: 0.81-3.55). The present data showed a high rate of women with excess pregestational weight, supporting the hypothesis that pregestational BMI may contribute to high birth weight babies and indicating the need for actions aiming to prevent excessive weight in women at reproductive age.

Association of genitourinary infections and cervical length with preterm childbirth

A prospective cohort study was conducted on a convenience sample of 1370 pregnant women with a gestational age of 20 to 25 weeks in the city of Ribeirão Preto. Data on obstetrical history, maternal age, parity, smoking habit, and a history of preterm delivery was collected with the application of a sociodemographic questionnaire. Cervical length was determined by endovaginal ultrasound, and urine and vaginal content samples were obtained to determine urinary tract infection (UTI) and bacterial vaginosis (BV), respectively. The aim of this study was to verify the association of cervical length and genitourinary infections with preterm birth (PTB). Ultrasound showed no association of UTI or BV with short cervical length. PTB rate was 9.63%. Among the women with PTB, 15 showed UTI (RR: 1.55, 95%CI: 0.93-2.58), 19 had BV (RR: 1.22, 95%CI: 0.77-1.94), and one had both UTI and BV (RR: 0.85, 95%CI: 0.13-5.62). Nineteen (14.4%) PTB occurred in women with a cervical length ≤2.5 cm (RR: 2.89, 95%CI: 1.89-4.43). Among the 75 patients with PTB stratified as spontaneous, 10 showed UTI (RR: 2.02, 95%CI: 1.05-3.86) and 14 had a diagnosis of BV (RR: 1.72, 95%CI: 0.97-3.04). A short cervical length between 20 and 25 weeks of pregnancy was associated with PTB, whereas UTI and BV determined at this age were not associated with short cervical length or with PTB, although UTI, even if asymptomatic, was related to spontaneous PTB.

Uterine vascular resistance and other maternal factors associated with the risk of developing hypertension during pregnancy

Gestational hypertension and pre-eclampsia are important causes of perinatal morbidity. The objective of the present study was to determine the increase in relative risk for developing hypertensive disorders of pregnancy based on the evaluation of pregnant women between 20 and 25 weeks of gestation, and to correlate the findings at this period with the outcome of pregnancy. We conducted a prospective cohort study, with a convenience sample of 1417 patients evaluated at this gestational age, of which 1306 were contacted at childbirth. We detected an increased relative risk of 2.69 (95%CI: 1.86 to 3.89) associated with pulsatility index of the uterine arteries, a 2.8 increase (95%CI: 1.58 to 5.03) in relative risk attributed to maternal age above 35 years, a 1.68 increase (95%CI: 1.17 to 2.40) attributed to parity greater than or equal to 3, and a 5.35 increase (95%CI: 4.18 to 6.85) attributed to chronic hypertension and obesity, with a progressive increase in relative risk according to the degree of overweight, i.e., grades 1, 2, 3, and morbid obesity (2.58, 3.06, 5.84, and 7.28, respectively).

Is soft drink consumption associated with gestational hypertension? Results from the BRISA cohort

It is still unknown whether excessive consumption of sugar-sweetened beverages may be linked to gestational hypertensive disorders, other than preeclampsia. This study investigated the association between soft drink consumption and hypertension during pregnancy, analyzing the relationship from the perspective of counterfactual causal theory. Data from pregnant women of the BRISA cohort were analyzed (1,380 in São Luis and 1,370 in Ribeirão Preto, Brazil). The explanatory variable was the frequency of soft drink consumption during pregnancy obtained in a prenatal interview. The outcome was gestational hypertension based on medical diagnosis, at the time of delivery. A theoretical model of the association between soft drink consumption and gestational hypertension was constructed using a directed acyclic graph. Marginal structural models (MSM) weighted by the inverse of the probability of soft drink consumption were also employed. Using Poisson regression analysis, high soft drink consumption (≥7 times/week) was associated with gestational hypertension in São Luís (RR=1.48; 95%CI: 1.03-2.10), in Ribeirão Preto (RR=1.51; 95%CI: 1.13-2.01), and in the two cohorts combined (RR=1.45; 95%CI: 1.16-1.82) compared to lower exposure (<7 times/week). In the MSM, the association between high soft drink consumption and gestational hypertension was observed in Ribeirão Preto (RR=1.63; 95%CI: 1.21-2.19) and in the two cohorts combined (RR=1.51; 95%CI: 1.15-1.97), but not in São Luís (RR=1.26; 95%CI: 0.79-2.00). High soft drink consumption seems to be a risk factor for gestational hypertension, suggesting that it should be discouraged during pregnancy.

Association of genitourinary infections and cervical length with preterm childbirth.

A prospective cohort study was conducted on a convenience sample of 1370 pregnant women with a gestational age of 20 to 25 weeks in the city of Ribeirão Preto. Data on obstetrical history, maternal age, parity, smoking habit, and a history of preterm delivery was collected with the application of a sociodemographic questionnaire. Cervical length was determined by endovaginal ultrasound, and urine and vaginal content samples were obtained to determine urinary tract infection (UTI) and bacterial vaginosis (BV), respectively. The aim of this study was to verify the association of cervical length and genitourinary infections with preterm birth (PTB). Ultrasound showed no association of UTI or BV with short cervical length. PTB rate was 9.63%. Among the women with PTB, 15 showed UTI (RR: 1.55, 95%CI: 0.93-2.58), 19 had BV (RR: 1.22, 95%CI: 0.77-1.94), and one had both UTI and BV (RR: 0.85, 95%CI: 0.13-5.62). Nineteen (14.4%) PTB occurred in women with a cervical length ≤2.5 cm (RR: 2.89, 95%CI: 1.89-4.43). Among the 75 patients with PTB stratified as spontaneous, 10 showed UTI (RR: 2.02, 95%CI: 1.05-3.86) and 14 had a diagnosis of BV (RR: 1.72, 95%CI: 0.97-3.04). A short cervical length between 20 and 25 weeks of pregnancy was associated with PTB, whereas UTI and BV determined at this age were not associated with short cervical length or with PTB, although UTI, even if asymptomatic, was related to spontaneous PTB.

A mathematical model for the evaluation of iron transport across the blood-cerebrospinal fluid barrier in neurodegenerative diseases.

Iron plays important roles in healthy brain but altered homeostasis and concentration have been correlated to aging and neurodegenerative diseases. Iron enters the central nervous system by crossing the brain barrier systems: the Blood- Brain Barrier separating blood and brain and the Blood-Cerebrospinal Fluid Barrier (BCSFB) between blood and CSF, which is in contact with the brain by far less selective barriers. Herein, we develop a two-compartmental model for the BCSFB, based on first-order ordinary differential equations, performing numerical simulations and sensitivity analysis. Furthermore, as input parameters of the model, experimental data from patients affected by Alzheimer's disease, frontotemporal dementia, mild cognitive impairment and matched neurological controls were used, with the aim of investigating the differences between physiological and pathological conditions in the regulation of iron passage between blood and CSF which can be possibly targeted by therapy.

Low-dose curcuminoid-loaded in dextran nanobubbles can prevent metastatic spreading in prostate cancer cells.

Preventing recurrences and metastasis of prostate cancer after prostatectomy by administering adjuvant therapies is quite a controversial issue. In addition to effectiveness, absence of side effects and long term toxicity are mandatory. Curcuminoids (Curc) extracted with innovative techniques and effectively loaded by polymeric nanobubbles (Curc-NBs) satisfy such requirements. Curc-NBs showed stable over 30 d, were effectively internalized by tumor cells and were able to slowly release Curc in a sustained way. Significant biological effects were detected in PC-3 and DU-145 cell lines where Curc-NBs were able to inhibit adhesion and migration, to promote cell apoptosis and to affect cell viability and colony-forming capacity in a dose-dependent manner. Since the favourable effects are already detectable at very low doses, which can be reached at a clinical level, the actual drug concentration can be visualized and monitored by US or MRI, Curc-NBs can be proposed as an effective adjuvant theranostic tool.

Cyclic nigerosyl-1,6-nigerose-based nanosponges: An innovative pH and time-controlled nanocarrier for improving cancer treatment.

The design and structural optimisation of a novel polysaccharide-based nanomaterial for the controlled and sustained release of doxorubicin are here reported. A cross-linked polymer was obtained by reacting a tetraglucose, named cyclic nigerosyl-1-6-nigerose (CNN), with pyromellitic dianhydride. The cross-linking reaction formed solid nanoparticles, named nanosponges, able to swell as a function of the pH. Nanoparticle sizes were reduced using High Pressure Homogenization, to obtain uniform nanosuspensions. Doxorubicin was incorporated into the CNN-nanosponges in a good extent. DSC and solid state NMR analyses proved the drug interaction with the polymer matrix. In vitro studies demonstrated pH-dependent slow and prolonged release kinetics of the drug from the nanoformulation. Doxorubicin-loaded CNN-nanosponges were easily internalized in A2780 cell line. They might considered an intracellular doxorubicin reservoir, able to slowly release the drug over time. CNN-nanosponges may be promising biocompatible nanocarriers for the sustained delivery of doxorubicin with potential localised application in cancer treatments.

Preparation and in vitro characterization of chitosan nanobubbles as theranostic agents.

Theranostic delivery systems are nanostructures that combine the modality of therapy and diagnostic imaging. Polymeric micro- and nanobubbles, spherical vesicles containing a gas core, have been proposed as new theranostic carriers for MRI-guided therapy. In this study, chitosan nanobubbles were purposely tuned for the co-delivery of prednisolone phosphate and a Gd(III) complex, as therapeutic and MRI diagnostic agent, respectively. Perfluoropentane was used for filling up the internal core of the formulation. These theranostic nanobubbles showed diameters of about 500nm and a positive surface charge that allows the interaction with the negatively charged Gd-DOTP complex. Pluronic F68 was added to the nanobubble aqueous suspension as stabilizer agent. The encapsulation efficiency was good for both the active compounds, and a prolonged drug release profile was observed in vitro. The effect of ultrasound stimulation on prednisolone phosphate release was evaluated at 37°C. A marked increase on drug release kinetics with no burst effect was obtained after the exposure of the system to ultrasound. Furthermore, the relaxivity of the MRI probe changed upon incorporation in the nanobubble shell, thereby offering interesting opportunity in dual MRI-US experiments. The ultrasound characterization showed a good in vitro echogenicity of the theranostic nanobubbles. In summary, chitosan drug-loaded nanobubbles with Gd(III) complex bound to their shell might be considered a new platform for imaging and drug delivery with the potential of improving anti-cancer treatments.

Beta-blockers for hemangiomas.

Infantile hemangiomas (IHs) are the most common tumors in infancy. Their typical natural history is characterized by an early rapid growth in the first months of life and by a slow spontaneous involution in the first years of life. Even though spontaneous regression of IHs could suggest therapeutic abstention, systemic treatment is the therapy of choice in many patients in which these situations occur: 1) rapid growth of IHs; 2) location of IHs in aesthetically critic areas; 3) recurrent hemorrhages, ulcerations or infections of IHs; 3) IHs interfering with important physiological functions (breathing, feeding, vision, hearing, etc.); 4) large or multicentric IHs that can cause heart failure. Since 2008, systemic administration of propranolol, an old non­selective ß­blocker, was found, serendipitously, to improve the treatment of IHs replacing older and more dangerous therapies like oral steroids, vincristine, interferon­alpha or vascular lasers. At present, oral propranolol has dramatically changed the approach of IHs because its efficacy is almost 100% and its action is rapid, without important side effects. The formal approval by FDA and EMA has been obtained in Spring 2014.

Desempenho reprodutivo do beijupirá (Rachycentron canadum) capturado no litoral de Pernambuco / Reproductive performance of cobia (Rachycentron canadum) captured of Pernambuco, Brazil

O desempenho reprodutivo de exemplares selvagens de beijupirá capturados no litoral de Pernambuco e aclimatados ao cativeiro foi avaliado durante 10 meses. Um plantel composto por duas fêmeas (peso de 14 a 16kg) e quatro machos (cerca de 12kg) mantidos em um único tanque de 70t produziu 48,7 milhões de ovos no período de outubro a junho. As fêmeas foram capazes de desovar 21 vezes, com uma frequência média (±DP) de uma desova a cada 11,9 dias (±2,9). Em média, cada desova produziu 2,4 milhões de ovos, com fertilização de 52,4 por cento, o que resultou em aproximadamente 1,0 milhão de larvas por desova. Os resultados demonstram a viabilidade da metodologia empregada na formação do plantel e no manejo de reprodutores e confirmam a relativa facilidade de obtenção de desovas espontâneas do beijupirá em cativeiro. Também foi confirmado que o período reprodutivo dessa espécie em cativeiro se estende além do observado na natureza. Este é o primeiro relato sobre o desempenho reprodutivo do beijupirá em cativeiro no Brasil...

The reproductive performance of wild cobia caught off the coast of Pernambuco, northeastern Brazil, was assessed. Six breeders (two females with 14-16kg and four males with approximately 12kg each) were maintained in a 70 ton tank from October to June and produced 48.7 million eggs. Females were able to spawn every 11.9 days (±2.9), which resulted in 21 spawns. On average each spawn produced 2.4 million eggs with a fertilization of 52.4 percent, which resulted in approximately 1.0 million larvae per spawn. The present results demonstrate the feasibility of the methodology employed here in the formation and management of a cobia breeding stock and confirm the ease of spawning cobia in captivity. It was also confirmed that the spawning season may be extended under captivity when compared to the wild stock. This is the first report on the reproductive performance of cobia in captivity in Brazil...

Multiple cutaneous and hepatic infantile hemangiomas having a successful response to propranolol as monotherapy at neonatal period.

Infantile hepatic hemangioma (IHH) is a common liver tumors of infancy with a higher incidence in females. Various treatments for infantile hepatic hemangioma such as systemic corticosteroids, interferon-alpha, vincristine and cyclophosphamide have been suggested, though no consensus exists about the first-choice treatment. Recent evidences suggest that propranolol, a nonselective ß-blocker, may be effective and safe as first-line therapy for infantile hepatic hemangioma. We report a case of female born at term with a weight of 2.450 g started to develop multiple cutaneous IHs at 10 days of age and presenting concomitant multiple cutaneous and hepatic infantile hemangiomas confirmed on magnetic resonance imaging. Propranolol, used as monotherapy, was started at 14 days of age at a dose of 2 mg/kg/day orally and maintained for 6 months. Patient was monitored in the hospital during first days of treatment with propranolol, and discharged after no side-effects were detected. Hepatic and cutaneous lesions had complete resolution in three months, although the fibro-fatty residuum of largest cutaneous nodule was still palpable at month 6. A further control after 6 months showed no recurrences. Our report case suggests that propranolol can be a safe and effective first-line therapy for neonates with concomitant multiple cutaneous and hepatic infantile hemangiomas.

[A new location of angiokeratoma circumscriptum]. / Une nouvelle localisation de l'angiokératome circonscrit næviforme.

BACKGROUND: Angiokeratomas are papular telangiectasias having a common histology of ectasia of the superficial dermal vessels surmounted by a hyperkeratotic epidermis. PATIENTS AND METHODS: The patient was a 9-year-old girl born of non-consanguineous parents after a well-followed pregnancy with problem-free delivery at term. From birth, she had a tumefaction of the left side of the nose and the left half of the upper lip that gradually increased in size without obstructing the nasal orifice and bled easily. Examination revealed the presence of tumefaction of the left nostril and the left half of the upper lip projecting towards the contralateral side especially in the nose. It was soft and painless, with the presence at the surface of dull red keratotic papules of 1 to 2 mm in diameter. Examination of the nasal mucosa revealed the same appearance of papules. DISCUSSION: Angiokeratoma circumscriptum is a rare congenital malformation, the rarest of five types. Since its initial description in 1890, few cases have been reported. However, female predominance has been noted with a male/female sex ratio of 1/3. It appears to be due to a genetic mutation that is probably autosomal, but the site of which is still unknown. In view of the special features of this case, several diagnoses were suggested, including Rendu Osler's disease, superficial lymphangioma and verrucous angioma. CONCLUSION: The particularity of this case is that it includes the first description of this site, which posed a therapeutic problem, especially concerning the choice of laser type to be used.

Tumor lysis syndrome after propranolol therapy in ulcerative infantile hemangioma: rare complication or incidental finding?

A 33-day-old female with an ulcerated infantile hemangioma (IH) undergoing oral therapy with propranolol 2 mg/kg per day developed hyperkalemia and hyperphosphatemia 24 h after starting medication. No electrocardiographic or clinical abnormalities secondary to the electrolyte changes were noticed. A laboratory tumor lysis syndrome (TLS) was diagnosed after excluding other causes of electrolyte imbalance in the diagnostic workup. No treatment was required to reverse the TLS condition, and the propranolol therapy was continued as the electrolyte alterations were only mild. One month later, the IH was remarkably reduced in size and no longer ulcerated. Maintenance of propranolol was extended for a total of 6 months. Parallel to the gradual involution of the IH, serum potassium and phosphorus levels returned within normal levels. We suggest that TLS may be a rare complication of ulcerated IH treated with propranolol. Clinicians must be aware and order appropriate screening tests for TLS in patients at risk.

Substituição do óleo de peixe por óleo de soja em dietas para beijupirá (Rachycentron canadum) / Replacement of fish oil by soybean oil in diets for cobia (Rachycentron canadum)

A substituição do óleo de peixe em dietas para beijupirá (Rachycentron canadum) foi avaliada usando-se cinco proporções de óleo de peixe e soja. Duzentos juvenis (±12g) foram distribuídos aleatoriamente em 20 tanques e alimentados até a saciedade aparente durante 42 dias. À medida que se aumentou o teor de óleo de peixe nas dietas, houve aumento proporcional no desempenho. Os juvenis alimentados com dietas que continham 75 e 100 por cento de óleo de peixe apresentaram ganhos de peso mais altos que os das dietas com 0 e 25 por cento de óleo de peixe, enquanto os alimentados com a dieta com 50 por cento de óleo de peixe apresentaram crescimento intermediário. Não foram observadas diferenças nas concentrações de proteína e lipídio na carcaça dos peixes, mas os teores de umidade e cinzas diferiram entre os tratamentos. A inclusão de teores relativamente altos de ingredientes de origem vegetal diminuiu o consumo alimentar, o que afetou negativamente o crescimento. Os resultados indicam a possibilidade de substituição de até 50 por cento do óleo de peixe por óleo de soja em dietas para juvenis do beijupirá.

The replacement of fish oil for cobia (Rachycentron canadum) in diets was evaluated using five proportions of fish oil:soybean oil. Two hundred juveniles (±12g) were randomly distributed in twenty 480L tanks and fed to apparent satiety twice daily for 42 days. Diets contained 12 percent lipids with different proportions of fish to soybean oils and were therefore named OP0, OP25, OP50, OP75 and OP100 according to the inclusion content of fish oil (0, 25, 50, 75 and 100 percent, respectively). Increasing dietary fish oil levels resulted in higher survival, growth and feed intake. Fish fed diets OP75 and OP100 presented higher weight gain than those fed diets OP0 and OP25, whereas fish fed diet OP50 had an intermediate weight gain. Overall, performance was enhanced at higher contents of dietary fish oil. No significant differences on protein and lipid content of fish carcass were observed, but moisture and ash content differed significantly between treatments. The inclusion of relatively higher contents of plant ingredients affected feed intake, which resulted in lower growth rates. The present results suggest the possibility of replacing up to 50 percent of fish oil with soybean oil in diets for cobia juveniles.

Poly(amidoamine)-Cholesterol Conjugate Nanoparticles Obtained by Electrospraying as Novel Tamoxifen Delivery System.

A new poly(amidoamine)-cholesterol (PAA-cholesterol) conjugate was synthesized, characterized and used to produce nanoparticles by the electrospraying technique. The electrospraying is a method of liquid atomization that consists in the dispersion of a solution into small charged droplets by an electric field. Tuning the electrospraying process parameters spherical PAA-chol nanoparticles formed. The PAA-cholesterol nanoparticles showed sizes lower than 500 nm and spherical shape. The drug incorporation capacity was investigated using tamoxifen, a lipophilic anticancer drug, as model drug. The incorporation of the tamoxifen did not affect the shape and sizes of nanoparticles showing a drug loading of 40%. Tamoxifen-loaded nanoparticles exhibited a higher dose-dependent cytotoxicity than free tamoxifen, while blank nanoparticles did not show any cytotoxic effect at the same concentrations. The electrospray technique might be proposed to produce tamoxifen-loaded PAA-chol nanoparticle in powder form without any excipient in a single step.

Electrospray technique for solid lipid-based particle production.

BACKGROUND: Different preparation methods for the production of lipid micro- and nanoparticles as controlled release formulations have been widely developed. Novel techniques are attracting increasing attention for their preparation. METHOD: The objective of the present investigation was to produce solid lipid-based micro-nanospheres using the electrohydrodynamic atomization (electrospraying) and to evaluate whether it is a suitable method to prepare drug-loaded particles. RESULTS: Narrowly dispersed spherical particles lower than 1 mum, easily internalized in cells, were obtained using stearic acid and ethylcellulose in a 4.5:0.5 (w/w) ratio. Tamoxifen, as model drug, was encapsulated with good entrapment efficiency. The in vitro release, after an initial burst effect, showed a prolonged drug release. CONCLUSION: The electrospraying method might be proposed to prepare in a single-step monodisperse lipid-based micro- and nanoparticles in powder form for drug delivery.