Gravity complexes as a focus of seafloor fluid seepage: the Rio Grande Cone, SE Brazil.

Seafloor methane emissions can affect Earth's climate and ocean chemistry. Vast quantities of methane formed by microbial decomposition of organic matter are locked within gas hydrate and free gas on continental slopes, particularly in large areas with high sediment accumulations such as deep-sea fans. The release of methane in slope environments has frequently been associated with dissociation of gas hydrates near the edge of the gas hydrate stability zone on the upper slope, with discharges in greater water depths less understood. Here we show, using data from the Rio Grande Cone (western South Atlantic), that the intrinsic, gravity-induced downslope collapse of thick slope sediment accumulations creates structures that serve as pathways for gas migration, unlocking methane and causing seafloor emissions via giant gas flares in the water column. The observed emissions in the study region (up to 310 Mg year-1) are three times greater than estimates for the entire US North Atlantic margin and reveal the importance of collapsing sediment accumulations for ocean carbon cycling. Similar outgassing systems on the Amazon and Niger fans suggest that gravity tectonics on passive margins is a common yet overlooked mechanism driving massive seafloor methane emissions in sediment-laden continental slopes.

Microwave-induced combustion for petroleum coke digestion: a promising sample preparation strategy for subsequent elemental determination.

The increasing demand for the elemental determination of petrochemical samples by inductively coupled plasma techniques requires the development of suitable sample preparation methods that permit high sample throughput and are in accordance with green chemistry recommendations. For this aim, the development of microwave-induced combustion (MIC) method has been attempted to completely digest petroleum coke samples and address quantitative determination of elements, such as Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Mg, Mn, Mo, Na, Ni, Pb, Sr, V and Zn, by inductively coupled plasma optical emission spectrometry (ICP OES). A sequential procedure to evaluate the sample mass and the solution to retain the analytes quantitatively was first conducted. Satisfactory results were obtained (residual carbon content in final solutions was lower than 0.5%) by digesting 400 mg of samples using 20 bar of oxygen and analytes were quantitatively retained in a dilute acid solution such as 4.2 mol L-1 HNO3. An agreement better than 87% was achieved using certified reference materials and the performance of the proposed method was also compared to that of the standard procedure recommended by the American Society of Testing and Materials ASTM D 5600. Despite both methods producing similar results, the proposed method by MIC was much simpler, offered a higher sample throughput and the digests were compatible with ICP OES measurements avoiding interferences in the determination step compared the ASTM D 5600 method. These results clearly demonstrated that the proposed MIC method in combination with ICP OES could be a promising alternative to obtain quantitative information about the elemental composition of petroleum coke.

Clinical safety of zafirlukast treatment during acute inflammatory reaction in nile tilapia (Oreochromis Niloticus)

Little is known about the toxicity of immune modulators in fish. Zafirlukast is an anti-inflammatory that antagonizes cysteine leukotriene receptors (CysLTR1). Aiming to study immunomodulatory treatments on fish health, this study evaluated the clinical safety of oral zafirlukast treatment, through biochemical and hematological analyzes during acute inflammatory reaction in Nile tilapia (Oreochromis niloticus), induced by Aeromonas hydrophilabacterins. 72 young tilapias were randomly divided in 9 aquariums (100 L each, n=8) to compose the following treatments: T0 (control), T1 (Treatment with 250 μg zafirlukast) and T2 (Treatment with 500 μg zafirlukast). Eight animals were evaluated per treatment in three periods: six, 24 and 48 hours post-inoculation (HPI), blood collection was performed for hematological and serum biochemical evaluation. The study of hepatic and renal functionality revealed that treatment with both doses of zafirlukast did not result in changes in the circulating values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, creatinine, triglycerides, cholesterol, and total protein, suggesting that the drug has not presented hepatotoxicity, as well as compromised liver and kidney functions. Tilapia submitted to treatment with 500 μg showed adverse hematological effects characterizedby polycythemia associated with microcytosis. Therefore, oral treatment with zafirlukast has demonstrated clinical safety at a therapeutic dose of 250 μg in tilapia during acute aerocystitis, although hematological changes were observed in tilapia treatedwith overdose of this leukotriene blocker.

Pouco se sabe sobre a toxicidade de imunomoduladores em peixes. Zafirlukast é um anti-inflamatório que antagoniza os receptores de leucotrienos cisteínicos (CysLTR1). Com o objetivo de estudar o efeito de tratamentos imunomoduladores sobre a saúde dos peixes, este estudo avaliou a segurança clínica do tratamento com zafirlucaste oral, por meio de análises bioquímicas e hematológicas durante reação inflamatória aguda em tilápia do Nilo (Oreochromis niloticus), induzida por bacterinas de Aeromonas hydrophila.Para tal, 72 tilápias jovens foram divididas aleatoriamente em 9 aquários (100 L cada, n=8) para compor os seguintes tratamentos: T0 (controle), T1 (Tratamento com 250 μg de zafirlucaste) e T2 (Tratamento com 500 μg de zafirlucaste). Oito animais foram avaliados por tratamento em três períodos: seis, 24 e 48 horas pós-inoculação (HPI), foi realizada coleta de sangue para avaliação hematológica e bioquímica sérica. O estudo da funcionalidade hepática e renal revelou que o tratamento com ambas as doses de zafirlucaste não resultou em alterações nos valores circulantes de aspartato aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina, creatinina, triglicerídeos, colesterol e proteína total, sugerindo que a droga não comprometeu as funçõeshepáticas e renais. As tilápias tratadas com 500 μg apresentaram efeitos hematológicos adversos caracterizados por policitemia associada a microcitose. Portanto, o tratamento oral com zafirlucaste demonstrou segurança clínica nadose de 250 μg em tilápiasdurante aerocistite aguda, embora alterações hematológicas tenham sido observadas em tilápias tratadas com sobredosagem deste bloqueador de leucotrieno.

Genetic polymorphisms in ß-defensin II gene in Amazon sheep from Brazil.

The northern region of Brazil produces a large number of sheep, with Pará being the largest sheep breeding state in the region. In the Amazon region, livestock production is a challenge due to the high diversity of pathogens affecting humans and animals. Defensins are antimicrobial peptides acting as a first barrier against micro-organisms and present high variation in different organisms. The objective of this study was to detect polymorphisms in exon II in ß-defensin II in Amazon sheep. The gene was amplified by PCR from DNA extracted from 47 sheep blood samples from the Santa Inês breed. Products were sequenced, aligned and analyzed. Three single nucleotide polymorphism (SNP) positions were observed with transition substitutions (A↔G) at positions 1643, 1659, and 1750. The 1643 and 1750 SNPs showed a low variability and significant deviations from Hardy-Weinberg equilibrium (HWE) (P < 0.05) meanwhile the SNP 1659 showed moderate absence of genetic variability and deviation from HWE (P > 0.05). Polymorphisms at 1643 and 1659 were predicted to modify amino acids in the peptide chain (isoleucine to valine and arginine to lysine, respectively) with no effects on protein function. Results from this study suggest that SNPs are important markers for ß-defensin II efficiency studies on the immune system of sheep in the Brazilian Amazon.

Conventional and Doppler ultrasonography on a goat with gangrenous mastitis / Ultrassonografia convencional e Doppler em cabra com mastite gangrenosa

Objetivou-se descrever os achados clínicos e ultrassonográficos de uma cabra leiteira apresentando mastite gangrenosa. Com a ultrassonografia convencional, observaram-se alterações consistentes com o avanço do quadro clínico, como alterações na ecogenicidade do leite e parênquima mamário. A ultrassonografia Doppler revelou aumento da velocidade de pico sistólico nos três momentos estudados, passando de 15 para 17 e 29cm/s. Houve redução, também, dos valores do índice de resistência, de 0,71 para 0,61 e 0,43. O índice de pulsatividade sofreu redução entre o segundo e o terceiro dia de observação, passando de 0,98 para 0,71. Foi possível estabelecer relação direta entre os achados ultrassonográficos e a gravidade da doença. A ultrassonografia convencional e Doppler podem ser utilizadas para o estudo hemodinâmico do úbere de cabras leiteiras, favorecendo diagnóstico e prognóstico de alterações nesse órgão...

The relevance of leukotrienes for bone resorption induced by mechanical loading.

5-Lipoxygenase (5-LO) metabolites are important pro-inflammatory lipid mediators. However, much still remains to be understood about the role of such mediators in bone remodeling. This study aimed to investigate the effect of 5-LO metabolites, LTB4 and CysLTs, in a model of mechanical loading-induced bone remodeling. Strain-induced tooth movement and consequently alveolar bone resorption/apposition was achieved by using a coil spring placed on molar and attached to incisors of C57BL6 (wild-type-WT), 5-LO deficient mice (5-LO(-/-)) and mice treated with 5-LO inhibitor (zileuton-ZN) or with antagonist of CysLTs receptor (montelukast-MT). The amount of bone resorption and the number of osteoclasts were determined morphometrically. The expression of inflammatory and bone remodeling markers in periodontium was analyzed by qPCR. Osteoclast differentiation and TNF-α production were evaluated in vitro using RAW 264.7 cells treated with LTB4 or LTD4. Bone resorption, TRAP(+) cells and expression of Tnfa, Il10 and Runx2 were significantly diminished in 5-LO(-/-), ZN- and MT-treated mice. The expression of Rank was also reduced in 5-LO(-/-) and MT-treated mice. Accordingly, LTB4 and LTD4 in association with RANKL promoted osteoclast differentiation and increased TNF-α release in vitro. These data demonstrate that the absence of 5-LO metabolites, LTB4 and CysLTs reduces osteoclast recruitment and differentiation, consequently diminishing bone resorption induced by mechanical loading. Thus, 5-LO might be a potential target for controlling bone resorption in physiological and pathological conditions.

Straight core structure of DNA replication origins in the mammalian AMPD2 locus.

Identification of the nucleotide consensus sequence in mammalian replication origins is a difficult and controversial problem. The hypothesis that local DNA topology could be involved in recognition by replication proteins is an exciting possibility. Secondary DNA structures, including intrinsically bent DNA, can be easily detected, and they may indicate a specific pattern in or near mammalian replication origins. This work presents the entire mapping of the intrinsically bent DNA sites (IBDSs), using in silico analysis and a circular permutation assay, of the DNA replication origins oriGNAI3, oriC, oriB, and oriA in the mammalian amplified AMPD2 gene domain. The results show that each origin presents an IBDS that flanks the straight core of these DNA replication sites. In addition, the in silico prediction of the nucleosome positioning reveals a strong indication that the center of an IBDS is localized in a nucleosome-free region (NFR). The structure of each of these curved sites is presented together with their helical parameters and topology. Together, the data that we present here indicate that the oriGNAI3 origin where preferential firing to the replication initiation events in the amplified AMPD2 domain occurs is the only origin that presents a straight, narrow region that is flanked on both sides by two intrinsically bent DNA sites within a short distance (~300 bp); however, all of the origins present at least one IBDS, which is localized in the NFR region. These results indicate that structural features could be implicated in the mammalian DNA replication origin and support the possibility of detecting and characterizing these segments.

The effects of parturition season and suckling mode on the puerperium of Santa Ines ewes and on the weight gain of lambs / Efeitos do período das parições e dos sistemas de amamentação sobre o puerpério de ovelhas Santa Inês e desempenho ponderal de cordeiros

Seventy-seven ewes were randomly divided into groups according to parturition season and suckling mode [Rainy season: continuous (n=14) and controlled (n=13); Dry season: continuous (n=25) and controlled (n=25)]. The controlled suckling mode, in both seasons, resulted in a decrease in variables, intervals between parturition and first estrus (reduction of 27.11 and 11.46 days for rainy and dry season, respectively; P<0.05) and between parturition and estrus of conception (reduction of 12.81 and 13.58 days, for rainy and dry season, respectively; P<0.05). As to the lambs, the weight gain was higher in animals subjected to controlled suckling in relation to continuous, especially when lambing occurred in the rainy season (17.83±0.56 vs. 13.95±0.52kg for Lambs' weight at 90 days old, respectively; P<0.05). Therefore, it was concluded that controlled suckling management is better indicated for the Amazonian region, since it allows the ewes to have a shorter puerperium period and the lambs exhibit higher weight gain.

Foram utilizadas 77 ovelhas, divididas aleatoriamente em grupos de acordo com o período de parição e o manejo de amamentação [chuvoso: contínua (n=14) e controlada (n=13); seco: contínua (n=25) e controlada (n=13)]. O sistema de amamentação controlado, em ambos os períodos, resultou em decréscimo para as variáveis intervalos entre parto e primeiro estro (redução de 27,11 e 11,46 dias para os períodos chuvoso e seco, respectivamente; P<0,05) e entre parto e estro da concepção (redução de 12,81 e 13,58 dia para os períodos chuvoso e seco, respectivamente; P<0,05). Quanto ao desempenho ponderal dos cordeiros, o ganho de peso foi maior para os animais submetidos ao regime de amamentação controlada em relação à contínua, especialmente quando os nascimentos ocorreram no período chuvoso (17,83±0,56 vs. 13,95±0,52kg para o peso dos cordeiros aos 90 dias de idade, respectivamente; P<0,05). Contudo, o manejo de amamentação controlada é indicado para a região amazônica, por permitir menor tempo de puerpério das ovelhas e maior ganho de peso dos cordeiros.

Prolactinoma: a condition associated with hypoadiponectinemia.

Prolactinomas are prolactin-secreting neoplasias accounting for 40% of the pituitary adenomas. Much is known about the effects of prolactinomas on the reproductive system, but few data are yet available regarding their induced changes on metabolism. This study was aimed at evaluating patients with prolactinomas for insulin resistance and adiponectinemia. Forty patients with prolactinoma were allocated to 2 different groups according to disease control: 20 with uncontrolled disease (UPRL) and 20 with controlled disease in the last 6 months (CPRL). Forty healthy individuals (CG) matched for age, sex, and body mass index were taken as controls. Patients with prolactinoma were compared both as a one group and according to disease control with CG. All subjects were evaluated for waist/hip ratio (WHR), blood pressure, lipid profile, fasting glucose, homeostasis assessment model of insulin resistance (HOMAIR), and adiponectin. Patients with prolactinomas (UPRL+CPRL) showed higher insulin (p<0.05) and HOMAIR (p<0.05), alongside with lower adiponectin levels (p<0.01) than matched controls. When UPRL was compared to CPRL and CG, UPRL was disclosed as a subgroup of significant altered metabolic profile as related to WHR (p<0.01 for comparisons), high-density lipoprotein cholesterol (p<0.05 for comparisons), triglycerides (p<0.05 for comparisons), HOMAIR (p<0.05 and p<0.01, respectively), and adiponectin (p<0.01 for comparisons). All these metabolic abnormalities, except hypoadiponectinemia (p<0.01), were not observed in CPRL. These data suggest that prolactinomas are associated with hypoadiponectinemia, which is further exacerbated in uncontrolled patients when insulin resistance is also prominent.

Laparoscopic ovum collection in sheep: gross and microscopic evaluation of the ovary and influence on ooctye production.

Gross and microscopic evaluations of the ovaries of sheep subjected to successive ovum collection were performed with the objective of identifying if there was interference in oocyte production and morphology of gonads. Gross evaluation of the internal genital tract was also performed. Eighteen ewes of the Santa Inês breed were randomly distributed into three experimental groups of six animals each; G0, G1 and G9 with no, one and nine repetitions, respectively. Estrous synchronization was achieved with a short protocol using MAP followed by single dose stimulation with 80mg of FSHp and 300 IU of eCG (IM). Laparoscopic ovum pick-up was performed 36h later, with 7-day intervals. The number of visualized follicles, aspirated follicles and oocytes recovery was recorded. After the last intervention, ovariectomy was performed for evaluation of gross and microscopical appearance and existence of lesions caused by follicular puncture, which were classified as absent (0), mild (1), moderate (2) and severe (3). The number of visualized follicles, aspirated follicles and oocytes recovery were 13.2±2.0, 11.3±3.0 and 5.8±2.3, respectively, with a recovery rate of 51.7%. No statistical difference was found between the nine sessions (P>0.05). Nine sessions of superovulation and ovum collection procedures did not cause ovarian lesions and did not interfere with the production of follicles in ewes of the Santa Inês breed.

Sensibilidade do Streptococcus pneumoniae aos antimicrobianos: resultados preliminares

Os autores realizaram um estudo para determinar a sensibilidade de estirpes do Streptococcus pneumoniae aos antibióticos. Cinqüenta e nove cepas foram testadas pelo método de Kirby Bauer e a maioria foi sensível a penicilina e ampicilina. Entretanto, houve 2 estirpes com resistência múltipla de 22,50% dos casos foram resistentes a associaçäo sulfametoxazol-trimetoprim. Discute-se a aplicaçäo desses resultados na prática clínica e em saúde pública