Ineffectiveness of information and access to health services: vulnerability to human papillomavirus.

AIM: To examine situations of vulnerability to human papillomavirus in the social representations of young women. BACKGROUND: Human papillomavirus is one of the most frequent sexually transmitted infections among women and constitutes a serious health problem among youth. This problem is embedded in psychosocial issues that promote situations of vulnerability and affect attitudes and behaviour in relation to prevention. METHODS: Qualitative study based on the theory of social representations, conducted among 64 female students in a high school in the city of Rio de Janeiro, Brazil. The study used personal semi-structured interviews, with a lexical analysis by Alceste 2010 software. FINDINGS: The inefficacy of information on the human papillomavirus pointed out individual and social vulnerabilities, and showed relationships between the difficulty of access and the perception of low quality in public health services, which also promotes institutional vulnerability. DISCUSSION: The representation of vulnerability to human papillomavirus infection is associated, not only with individual behaviours related to sexuality and gender identity but also to social and institutional conditions involving insufficient information and low quality of and ineffective access to public health services. CONCLUSION: Situations of vulnerability of young women to human papillomavirus infection influence ways of thinking and acting, when they generate feelings and behaviours that put them at risk. The social representations provided knowledge about how the participants appropriated consensual and reified universes in relation to vulnerability, influencing care and awareness of prevention. IMPLICATION FOR NURSING AND HEALTH POLICY: Situations of vulnerability, whether individual, social or institutional, warrant the attention of nurses and should be prioritized as public health policy goals to reduce the number of cases of human papillomavirus infection among younger women.

[The e-cigarette disrupts other consumptions in Parisian teenagers (2012-2014)]. / L'e-cigarette bouleverse les autres consommations des adolescents parisiens (2012 à 2014).

OBJECTIVES: To analyze experimentation with and use of e-cigarette by middle school and high school students in Paris. METHOD: Since 2012, questions about e-cigarette use have been included in the cross-sectional survey on tobacco that is administered annually since 1991 by the Paris sans tabac association. Overall, 2% of the 12-19 years-old attending school in Paris were surveyed. RESULTS: Of the 10,051 teenagers aged 12-19 surveyed in 2012-2014, 21.8% (n=2194) had tried e-cigarettes. Among these experimenters, 58.9% (n=1292) were smokers, 37.4% (n=820) were non-smokers and 3.7% (n=82) were ex-smokers. From 2012 to 2014, the rate of e-cigarette experimenters increased significantly (from 7.9% to 26.3% for 12-15 years and from 12.2% to 47.2% for 16-19 years-old). The rate of regular e-cigarettes users increased in the same proportion. However over this time, there has been a decline from 15.3% to 10.9% in the rate of 12-15 year old smokers (regular or occasional) and from 38.3% to 33.5% of smokers aged 16-19. Other consumption (cannabis, alcohol abuse) also decreased but no causal relationship can be established. CONCLUSION: The annual doubling of e-cigarette experimentation and regular use rates has been associated with a decrease in the consumption of tobacco and other products. These data should provide some reassurance against fears that e-cigarette use among young people will provide a significant gateway to tobacco smoking.

Toxicity assessment of TiO2 nanoparticles in zebrafish embryos under different exposure conditions.

The popularity of TiO2 nanoparticles (nano-TiO2) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO2 under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96h to different concentrations of nano-TiO2 in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO2 appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the factors involved in the toxicity of these nanoparticles, as well as to the establishment of protocols for risk assessments of nanotechnology.

Growth inhibitory effects of 3'-nitro-3-phenylamino nor-beta-lapachone against HL-60: a redox-dependent mechanism.

In this study, the cytotoxicity, genotoxicity and early ROS generation of 2,2-dimethyl-(3H)-3-(N-3'-nitrophenylamino)naphtho[1,2-b]furan-4,5-dione (QPhNO(2)) were investigated and compared with those of its precursor, nor-beta-lapachone (nor-beta), with the main goal of proposing a mechanism of antitumor action. The results were correlated with those obtained from electrochemical experiments held in protic (acetate buffer pH 4.5) and aprotic (DMF/TBABF(4)) media in the presence and absence of oxygen and with those from dsDNA biosensors and ssDNA in solution, which provided evidence of a positive interaction with DNA in the case of QPhNO(2). QPhNO(2) caused DNA fragmentation and mitochondrial depolarization and induced apoptosis/necrosis in HL-60 cells. Pre-treatment with N-acetyl-l-cysteine partially abolished the observed effects related to the QPhNO(2) treatment, including those involving apoptosis induction, indicating a partially redox-dependent mechanism. These findings point to the potential use of the combination of pharmacology and electrochemistry in medicinal chemistry.

Monitoramento do ácido chiquímico no manejo de plantas daninhas com glifosato em pomar comercial de citros / Shikimic acid monitoring in weed control with glyphosate in a commercial citrus orchard

Com o objetivo de verificar o acúmulo de ácido chiquímico em plantas de laranja pêra (Citrus sinensis) num pomar comercial manejado com glifosato, um herbicida sistêmico de amplo espectro, foram coletadas amostras na Fazenda Jequitibá, tradicional no cultivo de citros, situada no Município de Santo Antônio de Posse, SP. O produtor aplicou de forma convencional Roundup® Original a 1.440 g.ha-1 de equivalente ácido (e.a.) do sal de isopropilamino de glifosato em 19/12/ 2006 na entrelinha de 15 plantas, deixando outras cinco como testemunha. A reaplicação de glifosato a 1.260 g.ha-1 de e.a. foi realizada em 2/4/2007. Em ambos os casos, imediatamente antes da aplicação e aos 3, 7, 10, 15, 20 e 35 dias após, foram coletadas 20 folhas de cada planta tanto da área tratada como da não tratada, analisando-se o teor de ácido chiquímico por cromatografia líquida de alta eficiência (CLAE) de forma isocrática após extração por micro-ondas. Os resultados mostraram não ocorrer acúmulo do ácido chiquímico nas plantas de laranja pêra, não havendo diferenças significativas nos teores deste composto entre o material proveniente da área tratada com glifosato e o daquela capinada manualmente.

In order to check the accumulation of shikimic acid in a traditional commercial grove of citrus "Pêra" cultivar (Citrus sinensis) managed for weed control with glyphosate, a systemic herbicide with wide spectrum, samples were collected at Fazenda Jequitibá, in Santo Antonio de Posse County, São Paulo State, Brazil. The producer applied the following treatments of Roundup Original® glyphosate at 1,440 g.ha-1 a.e. of the isopropylamine salt on 19 December 2006 between rows of 15 plants, leaving five others as control. The reapplication of glyphosate at 1,260 g ha-1 was done on 2 April 2007. In both cases, immediately before application and at 3, 7, 10, 15, 20 and 35 days thereafter, 20 leaves from each treated and untreated plants were collected for analysis of the content of shikimic acid by isocratic high performance liquid chromatography (HPLC) assisted with microwave. The results showed no significant differences in levels of shikimic acid between the material from the area treated with glyphosate and that weeded manually.

Adaptation to a high protein, carbohydrate-free diet induces a marked reduction of fatty acid synthesis and lipogenic enzymes in rat adipose tissue that is rapidly reverted by a balanced diet.

We have previously shown that in vivo lipogenesis is markedly reduced in liver, carcass, and in 4 different depots of adipose tissue of rats adapted to a high protein, carbohydrate-free (HP) diet. In the present work, we investigate the activity of enzymes involved in lipogenesis in the epididymal adipose tissue (EPI) of rats adapted to an HP diet before and 12 h after a balanced diet was introduced. Rats fed an HP diet for 15 days showed a 60% reduction of EPI fatty acid synthesis in vivo that was accompanied by 45%-55% decreases in the activities of pyruvate dehydrogenase complex, ATP-citrate lyase, acetyl-CoA carboxylase, glucose-6-phosphate dehydrogenase, and malic enzyme. Reversion to a balanced diet for 12 h resulted in a normalization of in vivo EPI lipogenesis, and in a restoration of acetyl-CoA carboxylase activity to levels that did not differ significantly from control values. The activities of ATP-citrate lyase and pyruvate dehydrogenase complex increased to about 75%-86% of control values, but the activities of glucose-6-phosphate dehydrogenase and malic enzyme remained unchanged 12 h after diet reversion. The data indicate that in rats, the adjustment of adipose tissue lipogenic activity is an important component of the metabolic adaptation to different nutritional conditions.

Identification of anaerobic threshold using heart rate response during dynamic exercise.

The objective of the present study was to characterize the heart rate (HR) patterns of healthy males using the autoregressive integrated moving average (ARIMA) model over a power range assumed to correspond to the anaerobic threshold (AT) during discontinuous dynamic exercise tests (DDET). Nine young (22.3 +/- 1.57 years) and 9 middle-aged (MA) volunteers (43.2 +/- 3.53 years) performed three DDET on a cycle ergometer. Protocol I: DDET in steps with progressive power increases of 10 W; protocol II: DDET using the same power values as protocol 1, but applied randomly; protocol III: continuous dynamic exercise protocol with ventilatory and metabolic measurements (10 W/min ramp power), for the measurement of ventilatory AT. HR was recorded and stored beat-to-beat during DDET, and analyzed using the ARIMA (protocols I and II). The DDET experiments showed that the median physical exercise workloads at which AT occurred were similar for protocols I and II, i.e., AT occurred between 75 W (116 bpm) and 85 W (116 bpm) for the young group and between 60 W (96 bpm) and 75 W (107 bpm) for group MA in protocols I and II, respectively; in two MA volunteers the ventilatory AT occurred at 90 W (108 bpm) and 95 W (111 bpm). This corresponded to the same power values of the positive trend in HR responses. The change in HR response using ARIMA models at submaximal dynamic exercise powers proved to be a promising approach for detecting AT in normal volunteers.

Identification of anaerobic threshold using heart rate response during dynamic exercise

The objective of the present study was to characterize the heart rate (HR) patterns of healthy males using the autoregressive integrated moving average (ARIMA) model over a power range assumed to correspond to the anaerobic threshold (AT) during discontinuous dynamic exercise tests (DDET). Nine young (22.3 ± 1.57 years) and 9 middle-aged (MA) volunteers (43.2 ± 3.53 years) performed three DDET on a cycle ergometer. Protocol I: DDET in steps with progressive power increases of 10 W; protocol II: DDET using the same power values as protocol 1, but applied randomly; protocol III: continuous dynamic exercise protocol with ventilatory and metabolic measurements (10 W/min ramp power), for the measurement of ventilatory AT. HR was recorded and stored beat-to-beat during DDET, and analyzed using the ARIMA (protocols I and II). The DDET experiments showed that the median physical exercise workloads at which AT occurred were similar for protocols I and II, i.e., AT occurred between 75 W (116 bpm) and 85 W (116 bpm) for the young group and between 60 W (96 bpm) and 75 W (107 bpm) for group MA in protocols I and II, respectively; in two MA volunteers the ventilatory AT occurred at 90 W (108 bpm) and 95 W (111 bpm). This corresponded to the same power values of the positive trend in HR responses. The change in HR response using ARIMA models at submaximal dynamic exercise powers proved to be a promising approach for detecting AT in normal volunteers.

Effect of the leaving group on the electrodic reduction mechanism of anti-Helicobacter pylori metronidazole derivatives, in aprotic and protic media.

Because redox properties are central to bioreductive drug activity and selectivity, six 2-methyl-5-nitroimidazole, substituted at the N1-ethyl side chain with I, Br, Cl, OAc, OMs and NH(3)(+) were synthesized and submitted to cyclic voltammetry and electrolyses, in order to define their electrodic reduction mechanism, in aprotic [dimethylsulphoxide (DMSO)+0.1 mol l(-1) tetrabuthylammonium perchlorate (TBAP)] and phosphate-buffered media, on glassy carbon electrode, in comparison with metronidazole. Three of these compounds, namely, the iodo, bromo and ammonium salt derivatives showed significant anti-Helicobacter pylori (strain resistant to metronidazole) activity. All the cyclic voltammograms (CV), in aprotic medium, are similar to the one for metronidazole, except for -I, -Br and -NH(3)(+) derivatives. The CV of the N1-ethylhalide (-I, -Br) 5-nitroimidazole showed more intense and irreversible first waves, even at faster sweep rates (nu<2 V s(-1)). The absence of the first wave anodic counterpart, along with analysis of the dependence of E(p), I(p) and other parameters with nu, and results from electrolysis (consumption of two electrons) showed the process to be an ECE system, with halide release, after uptake of two electrons. This behaviour represents a case of dissociative electron transfer (ET). For the ammonium salt, self-protonation mechanism was evident. The facility of reduction represented by the first wave potential and concerning the substituents is NH(3)(+)>Br>I>Cl>OMs>OH>OAc. In aqueous phosphate-buffered medium, the electrochemical behaviour of all the compounds is similar to the one of metronidazole, represented by a unique and irreversible 4e(-)/4H(+) wave. The order of reduction ease is NH(3)(+)>Br approximately OMs>I>OH>OAc. Aprotic medium allows a better discrimination between the substituents. Concerning biological activity, despite the impossibility of establishing a correlation, it has been observed that the more electrophilic compounds showed better anti-H. pylori activity.

Control of glyceroneogenic activity in rat brown adipose tissue.

Brown adipose tissue (BAT) glyceroneogenesis was evaluated in rats either fasted for 48 h or with streptozotocin-diabetes induced 3 days previously or adapted for 20 days to a high-protein, carbohydrate-free (HP) diet, conditions in which BAT glucose utilization is reduced. The three treatments induced an increase in BAT glyceroneogenic activity, evidenced by increased rates of incorporation of [1-14C]pyruvate into triacylglycerol (TAG)-glycerol in vitro and a marked, threefold increase in the activity of BAT phosphoenolpyruvate carboxykinase (PEPCK). BAT glycerokinase activity was not significantly affected by fasting or diabetes. After unilateral BAT denervation of rats fed either the HP or a balanced diet, glyceroneogenesis activity increased in denervated pads, evidenced by increased rates of nonglucose carbon incorporation into TAG-glycerol in vivo (difference between 3H2O and [14C]glucose incorporations) and of [1-14C]pyruvate in vitro. PEPCK activity was not significantly affected by denervation. The data suggest that BAT glyceroneogenesis is not under sympathetic control but is sensitive to hormonal/metabolic factors. In situations of reduced glucose use there is an increase in BAT glyceroneogenesis that may compensate the decreased generation of glycerol-3-phosphate from the hexose.

Glucose uptake, glucose transporter GLUT4, and glycolytic enzymes in brown adipose tissue from rats adapted to a high-protein diet.

In vivo rates of glucose uptake, insulin-responsive glucose transporter (GLUT4) content, and activities of glycolytic enzymes were determined in brown adipose tissue (BAT) from rats adapted to a high-protein, carbohydrate-free (HP) diet. Adaptation to the HP diet resulted in marked decreases in BAT glucose uptake and in GLUT4 content. Replacement of the HP diet by a balanced control diet for 24 hours restored BAT glucose uptake to levels above those in rats fed the control diet, with no changes in GLUT4 levels in 4 of 5 animals examined. BAT denervation of rats fed the control diet induced a 50% reduction in glucose uptake, but did not significantly affect the already markedly reduced BAT hexose uptake in HP diet-fed rats. It is suggested that the pronounced decrease in BAT glucose uptake in these animals is due to the combined effects of the HP diet-induced reductions in plasma insulin levels and in BAT sympathetic activity. Adaptation to the HP diet was accompanied by decreased activities of hexokinase, phosphofructo-1-kinase, and pyruvate kinase (PK). The activity of BAT PK in HP diet-fed rats was reduced to about 50% of controls, and approached normal levels 24 hours after diet reversion. BAT denervation induced a small (15%) decrease in BAT PK activity in control rats, but did not affect the activity of the enzyme in HP diet-adapted rats. Also, denervation did not interfere with the restoration of PK activity induced by diet substitution. Treatment with anti-insulin serum resulted in an almost 50% reduction in PK activity in both innervated and denervated BAT from rats fed the control diet, but caused a much smaller ( thick approximate 20%) decrease in BAT from HP diet-fed rats. Furthermore, anti-insulin serum administration completely suppressed the restoration of BAT PK activity induced by diet reversion. These data suggest that, differently from glucose uptake, BAT PK activity is predominantly controlled by hormonal/metabolic factors.

Relative importance of sympathetic outflow and insulin in the reactivation of brown adipose tissue lipogenesis in rats adapted to a high-protein diet.

The effect of denervation or acute insulin deficiency on brown adipose tissue lipogenesis was investigated in rats adapted to a high-protein diet before and after diet reversion to a balanced diet. Denervation of rats fed the balanced diet induced a 50% reduction in in vivo rates of brown adipose tissue fatty acid synthesis, with decreased activities of acetyl-CoA carboxylase and adenosine triphosphate (ATP)-citrate lyase. The markedly (80%) reduced fatty acid synthesis and enzyme activities in brown adipose tissue from rats adapted to the high-protein diet were not affected by denervation. Replacement of the high-protein diet by the balanced diet for 24 hours restored fatty acid synthesis to normal levels, but recovery of enzyme activities was only partial. Lipogenesis restoration and partial recovery of enzyme activities were impaired in denervated tissue from high-protein diet-fed rats. In all experimental conditions, the activities of acetyl-CoA carboxylase and ATP-citrate lyase showed a better correlation with brown adipose tissue lipogenesis than the generators of H(+), glucose-6-P dehydrogenase, and malic enzyme. Anti-insulin serum administration during the 12- to 24-hour period after diet reversion completely blocked lipogenesis recovery in innervated and denervated tissues and drastically reduced brown adipose tissue lipogenesis of concomitantly injected rats fed the balanced diet. The data suggest that efficient and rapid adjustments of brown adipose tissue lipogenesis require sympathetic activation, and that this tissue can maintain significant, albeit reduced, rates of lipogenesis in the absence of sympathetic activation, but not in the absence of insulin.

Glycerokinase activity in brown adipose tissue: a sympathetic regulation?

The effect of brown adipose tissue (BAT) sympathetic hemidenervation on the activity of glycerokinase (GyK) was investigated in different physiological conditions. In rats fed a balanced diet, the activity of the enzyme was approximately 50% lower in BAT-denervated pads than in intact, innervated pads. In rats adapted to a high-protein, carbohydrate-free diet, norepinephrine turnover rates and BAT GyK activity were already reduced, and BAT denervation resulted in a further decrease in the activity of the enzyme. Cold acclimation of normally fed rats at 4 degrees C for 10 days markedly increased the activity of the enzyme. Cold exposure (4 degrees C) for 6 h was insufficient to stimulate BAT GyK, but the activity of the enzyme was already increased after 12 h of cold exposure. The cold-induced BAT GyK stimulation was completely blocked in BAT-denervated pads. The data indicate that an adequate sympathetic flow to BAT is required for the maintenance of normal levels of GyK activity and for the enzyme response to situations, such as cold exposure, which markedly increase BAT sympathetic flow.

Effects of submaximal exercise with water ingestion on intraocular pressure in healthy human males

The effects of exercise and water replacement on intraocular pressure (IOP) have not been well established. Furthermore, it is not known whether the temperature of the fluid ingested influences the IOP response. In the present study we determined the effect of water ingestion at three temperatures (10, 24 and 38ºC; 600 ml 15 min before and 240 ml 15, 30 and 45 min after the beginning of each experimental session) on the IOP of six healthy male volunteers (age = 24.0 ± 3.5 years, weight = 67.0 ± 4.8 kg, peak oxygen uptake (VO2peak) = 47.8 ± 9.1 ml kg-1 min-1). The subjects exercised until exhaustion on a cycle ergometer at a 60 percent VO2peak in a thermoneutral environment. IOP was measured before and after exercise and during recovery (15, 30 and 45 min) using the applanation tonometry method. Skin and rectal temperatures, heart rate and oxygen uptake were measured continuously. IOP was similar for the right eye and the left eye and increased post-water ingestion under both exercising and resting conditions (P<0.05) but did not differ between resting and exercising situations, or between the three water temperatures. Time to exhaustion was not affected by the different water temperatures. Rectal temperature, hydration status, heart rate, oxygen uptake, carbon dioxide extraction and lactate concentration were increased by exercise but were not affected by water temperature. We conclude that IOP was not affected by exercise and that water ingestion increased IOP as expected, regardless of water temperature

Effects of submaximal exercise with water ingestion on intraocular pressure in healthy human males.

The effects of exercise and water replacement on intraocular pressure (IOP) have not been well established. Furthermore, it is not known whether the temperature of the fluid ingested influences the IOP response. In the present study we determined the effect of water ingestion at three temperatures (10, 24 and 38 degrees C; 600 ml 15 min before and 240 ml 15, 30 and 45 min after the beginning of each experimental session) on the IOP of six healthy male volunteers (age = 24.0 +/- 3.5 years, weight = 67.0 +/- 4.8 kg, peak oxygen uptake (VO2peak) = 47.8 +/- 9.1 ml kg-1 min-1). The subjects exercised until exhaustion on a cycle ergometer at a 60% VO2peak in a thermoneutral environment. IOP was measured before and after exercise and during recovery (15, 30 and 45 min) using the applanation tonometry method. Skin and rectal temperatures, heart rate and oxygen uptake were measured continuously. IOP was similar for the right eye and the left eye and increased post-water ingestion under both exercising and resting conditions (P<0.05) but did not differ between resting and exercising situations, or between the three water temperatures. Time to exhaustion was not affected by the different water temperatures. Rectal temperature, hydration status, heart rate, oxygen uptake, carbon dioxide extraction and lactate concentration were increased by exercise but were not affected by water temperature. We conclude that IOP was not affected by exercise and that water ingestion increased IOP as expected, regardless of water temperature.

Effect of cold acclimation on brown adipose tissue fatty acid synthesis in rats adapted to a high-protein, carbohydrate-free diet.

The effect of cold acclimation on brown adipose tissue (BAT) fatty acid synthesis was investigated in rats adapted to a high-protein, carbohydrate-free diet. At an ambient temperature (25 degrees C), rates of fatty acid synthesis in BAT from rats adapted to the high-protein diet were reduced to 27% of rats fed the balanced diet and increased markedly after cold acclimation (10 days at 4 degrees C), although the increase was smaller than in control rats. BAT weight increase induced by cold acclimation was smaller in rats fed the high-protein diet (30%) than in controls (100%). When expressed per whole tissue, maximal activities of BAT glucose-6-phosphate dehydrogenase, malic enzyme, adenosine triphosphate (ATP)-citrate lyase, and acetyl-coenzyme A carboxylase were markedly reduced in high-protein diet-adapted rats at 25 degrees C and increased after cold acclimation in BAT from the 2 groups. However, when expressed per milligram protein, only acetyl-coenzyme A carboxylase showed an increase in both controls and in rats fed the high-protein diet. G6P-dehydrogenase, malic enzyme, and ATP-citrate lyase increased (per milligram protein) only in rats adapted to the high-protein diet and actually decreased in BAT from cold-acclimated control rats. Initial (before activation) pyruvate dehydrogenase (PDH) complex activity was lower in BAT from rats fed the high-protein diet at 25 degrees C and increased in cold-acclimated rats from the 2 groups. Circulating levels of insulin decreased in the 2 groups after cold acclimation. The data suggest that the cold acclimation-induced increase in BAT lipogenesis in rats adapted to the high-protein diet was due to a restoration of sympathetic activity, which induced both BAT hyperplasia and activation of adipocyte free fatty acid (FFA) synthesis, with an important participation of acetyl-coenzyme A carboxylase and pyruvate dehydrogenase.

Glucose uptake and glycolytic flux in adipose tissue from rats adapted to a high-protein, carbohydrate-free diet.

Rates of glucose uptake by epididymal and retroperitoneal adipose tissue in vivo, as well as rates of hexose uptake and glycolytic flux in isolated adipocytes, were determined in rats adapted to a high-protein, carbohydrate-free (HP) diet and in control rats fed a balanced (N) diet. Adaptation to the HP diet induced a significant reduction in rates of glucose uptake, estimated with 2-deoxy-[1-(3)H]-glucose, both by adipose tissue (epididymal and retroperitoneal) in vivo and by isolated adipocytes. Twelve hours after replacement of the HP diet with the balanced diet, rates of adipose tissue uptake in vivo in HP-adapted rats returned to levels that did not differ significantly from those in N-fed rats. The rate of flux in the glycolytic pathway, estimated with (3)H[5]-glucose, was also significantly reduced in adipocytes from HP-fed rats. In agreement with the above findings, the activities of hexokinase (HK), phosphofructo-1-kinase (PFK-1), and pyruvate kinase (PK) were markedly reduced in adipose tissue from HP-adapted rats. The activity of pyruvate kinase was partially reverted by diet replacement for 12 hours. The low-plasma insulin and high-glucagon levels in HP-fed rats may have played an important role in the reduction of adipose tissue glucose utilization in these animals.

Feed training of peacock bass (Cichla sp)

The Amazonian cichlid peacock bass (Cichla sp.) is a highly marketable food and sport fish, therefore a suitable species for aquaculture. However, because of its piscivorous feeding preferences, the species does not accept dry feeds voluntarily, turning its intensive culture difficult and costly. This study aimed to wean fingerling peacock bass from inert moist food to dry diets. In a first experiment, 1,134 fingerlings weighting 0.27 g were divided in two 0.37 m³ hapas and fed ground fish flesh with 35 percent success. Then, 1.3 g fish were pooled, stocked in six 25 L cages and fed two pellet sequences with 80 percent, 60 percent, 40 percent, 20 percent and 0 percent ground fish flesh (GFF). One sequence was flavored with 10 percent krill meal (Euphausia sp.). Training success of fish fed the GFF-00 diet flavored with krill reached 12 percentª compared to 11.6 percentª (p < 0.05) for diets without krill meal. A second experiment was set up with 969, 1.5 g fish, trained with GFF with 39.8 percent success. After the feed training period, 2.2 g fish were then fed a sequence of moist pellets containing 80 percent, 60 percent and 45 percent GFF. Fish trained to feed on moist pellets with 45 percent ground fish were pooled and stocked into nine 25 L cages. Fish were weaned to dry pellets without ground fish flesh (GFF-00) using three diet sequences: 1) dry pellets; 2) moist pellets; and 3) dry pellets flavored with 4 percent cod liver oil; all three diets contained 30, 10 and 0 percent GFF. The three sequences yielded, respectively 30.8 percentª, 23.6 percentª, and 24.7 percentª (p < 0.05) fish feeding on GFF-00. There were no apparent beneficial effects of increasing moisture or addition of cod liver oil as flavor enhancers in the weaning diets. This study revealed the feasibility of training peacock bass to accept dry pellets, but feeding young fish ground fish flesh seemed to be a major bottleneck in improving feed training success

Feed training of peacock bass (Cichla sp.).

The Amazonian cichlid peacock bass (Cichla sp.) is a highly marketable food and sport fish, therefore a suitable species for aquaculture. However, because of its piscivorous feeding preferences, the species does not accept dry feeds voluntarily, turning its intensive culture difficult and costly. This study aimed to wean fingerling peacock bass from inert moist food to dry diets. In a first experiment, 1,134 fingerlings weighting 0.27 g were divided in two 0.37 m3 hapas and fed ground fish flesh with 35% success. Then, 1.3 g fish were pooled, stocked in six 25 L cages and fed two pellet sequences with 80%, 60%, 40%, 20% and 0% ground fish flesh (GFF). One sequence was flavored with 10% krill meal (Euphausia sp.). Training success of fish fed the GFF-00 diet flavored with krill reached 12%a compared to 11.6%a (p < 0.05) for diets without krill meal. A second experiment was set up with 969, 1.5 g fish, trained with GFF with 39.8% success. After the feed training period, 2.2 g fish were then fed a sequence of moist pellets containing 80%, 60% and 45% GFF. Fish trained to feed on moist pellets with 45% ground fish were pooled and stocked into nine 25 L cages. Fish were weaned to dry pellets without ground fish flesh (GFF-00) using three diet sequences: 1) dry pellets; 2) moist pellets; and 3) dry pellets flavored with 4% cod liver oil; all three diets contained 30, 10 and 0% GFF. The three sequences yielded, respectively 30.8%a, 23.6%a, and 24.7%a (p < 0.05) fish feeding on GFF-00. There were no apparent beneficial effects of increasing moisture or addition of cod liver oil as flavor enhancers in the weaning diets. This study revealed the feasibility of training peacock bass to accept dry pellets, but feeding young fish ground fish flesh seemed to be a major bottleneck in improving feed training success.

Brown adipose tissue triacylglycerol synthesis in rats adapted to a high-protein, carbohydrate-free diet.

Adaptation of rats to a high-protein, carbohydrate-free (HP) diet induced a marked reduction of brown adipose tissue (BAT) fatty acid (FA) synthesis from both 3H2O and [14C]glucose in vivo, with pronounced decreases in the activities of four enzymes associated with lipogenesis: glucose-6-phosphate dehydrogenase, malic enzyme, citrate lyase, and acetyl-CoA carboxylase. In both HP-adapted and control rats, in vivo incorporation of 3H2O and [14C]glucose into BAT glyceride-glycerol was much higher than into FA. It could be estimated that most of the glycerol synthetized was used to esterify preformed FA. Glycerol synthesis from nonglucose sources (glyceroneogenesis) was increased in BAT from HP rats, as evidenced by an increased capacity of tissue fragments to incorporate [1-14C]pyruvate into glycerol and by a fourfold increase in the activity of phosphoenolpyruvate carboxykinase activity, a key glyceroneogenic enzyme. The data suggest that high rates of glyceroneogenesis and of esterification of preformed FA in BAT from HP-adapted rats are essential for preservation of tissue lipid stores, necessary for heat generation when BAT is recruited in nonshivering thermogenesis.