On line pre-concentration for simultaneous determination of low molecular weight organic acids and inorganic anions in Amazonian river water samples employing ion chromatography with conductivity detection

An ion chromatography procedure, employing an IonPac AC15 concentrator column was used to investigate on line preconcentration for the simultaneous determination of inorganic anions and organic acids in river water. Twelve organic acids and nine inorganic anions were separated without any interference from other compounds and carry-over problems between samples. The injection loop was replaced by a Dionex AC15 concentrator column. The proposed procedure employed an auto-sampler that injected 1.5 ml of sample into a KOH mobile phase, generated by an Eluent Generator, at 1.5 mL min-1, which carried the sample to the chromatographic columns (one guard column, model AG-15, and one analytical column, model AS15, with 250 x 4mm i.d.). The gradient elution concentrations consisted of a 10.0 mmol l-1 KOH solution from 0 to 6.5 min, gradually increased to 45.0 mmol l-1 KOH at 21 min., and immediatelly returned and maintained at the initial concentrations until 24 min. of total run. The compounds were eluted and transported to an electro-conductivity detection cell that was attached to an electrochemical detector. The advantage of using concentrator column was the capability of performing routine simultaneous determinations for ions from 0.01 to 1.0 mg l-1 organic acids (acetate, propionic acid, formic acid, butyric acid, glycolic acid, pyruvate, tartaric acid, phthalic acid, methanesulfonic acid, valeric acid, maleic acid, oxalic acid, chlorate and citric acid) and 0.01 to 5.0 mg l-1 inorganic anions (fluoride, chloride, nitrite, nitrate, bromide, sulfate and phosphate), without extensive sample pretreatment and with an analysis time of only 24 minutes.

Optimum dietary protein requirement for Amazonian Tambaqui, Colossoma macropomum Cuvier, 1818, fed fish meal free diets

Fish meal free diets were formulated to contain graded protein levels as 25% (diet 1), 30% (diet 2), 35% (diet 3) and 40% (diet 4). The diets were fed to tambaqui juveniles (Colossoma macropomum) (46.4 ± 6.3g) in randomly designed recirculating systems for 60 days, to determine the optimum protein requirement for the fish. The final weight of the fish, weight gain (28.1, 28.5, 32.2, 28.0g) and specific growth rate increased (P>0.05) consistently with increasing dietary protein up to treatment with 35% protein diet and then showed a declining trend. Feed intake followed the same trend resulting in best feed efficiency (62.5%) in fish fed diet with 35% protein. Similarly, the protein intake increased significantly with increasing dietary protein levels and reduced after the fish fed with 35% protein; while protein efficiency ratio (2.28, 1.99, 1.87, 1.74) decreased with increasing dietary protein levels. Carcass ash and protein had linear relationship with dietary protein levels while the lipid showed a decreasing trend. Ammonia content (0.68, 0.73, 0.81, 1.21 mg L-1) of the experimental waters also increased (P<0.05) with increasing protein levels while pH, dissolved oxygen and temperature remained fairly constant without any clear pattern of inclination. Broken-line estimation of the weight gain indicated 30% protein as the optimum requirement for the fish.

Taxocenose de Scarabaeinae (Coleoptera: Scarabaeidae) em Benjamin Constant, AM

As espécies de Scarabaeinae coletadas em seis diferentes sistemas de uso da terra em Benjamin Constant, AM, Brasil, são listadas com comentários gerais sobre os gêneros e espécies registradas. Os besouros foram capturados com armadilhas do tipo pitfall iscadas com fezes humanas. Foram coletados 6792 indivíduos pertencentes a 63 espécies, 18 gêneros e seis tribos (Ateuchini, Canthonini, Coprini, Oniticellini, Onthophagini e Phanaeini). As espécies mais frequentes foram Pseudocanthon aff. xanthurus (Blanchard 1845), Eurysternus caribaeus (Herbst 1789), Eurysternus hypocrita Balthasar 1939, Onthophagus aff. acuminatus Harold 1880, Onthophagus aff. haematopus Harold 1875 e Onthophagus aff. bidentatus (Drapiez 1819). Foi encontrado um novo gênero de Scarabaeinae ainda não descrito e provavelmente outras espécies novas.

Heart Weight and Heart Weight/Body Weight Coefficient in Malnourished Adults

OBJECTIVE: To compare the heart weight and the heart weight/body weight coefficient of adults with and without chronic malnutrition. METHODS: In an initial case series of 210 autopsies performed in adults, we recorded body and heart weights and calculated the heart weight/body weight coefficients (HW/BW x 100). The exclusion criteria were as follows: positive serology for Chagas' disease, edema, obesity, heart diseases, hepatopathies, nephropathies, and systemic arterial hypertension. Malnutrition was characterized as a body mass index <18.5kg/m². Differences with p<0.05 were considered significant. RESULTS: Individuals in the malnourished (n=15) and control (n=21) groups were statistically different, respectively, in regard to body mass index (15.9±1.7 versus 21.3±2.5kg/m²), heart weight (267.3±59.8 versus 329.1±50.4g), and the HW/BW coefficient (0.64±0.12 versus 0.57±0.09%). A positive and significant correlation was observed between heart weight and body mass index (r=0.52), and between heart weight and body weight (r=0.65). CONCLUSION: Malnourished individuals have lighter hearts and a greater HW/BW coefficient than non-malnourished individuals do. These findings indicate a possible preservation of the myocardium in relation to the intensity of weight loss associated with the probable relative increase in cardiac connective tissue and heart blood vessels.

Self-perception and dissatisfaction with weight does not depend on the frequency of physical activity

OBJECTIVE: To evaluate the level of satisfaction with body weight and the self-perception of the weight/height ratio and to verify the influence of the frequency of present and past physical activity on these variables. METHODS: Using questionnaires or interviews, we obtained height data, reported and desired weight, self-perception of the weight/height ratio, and the frequency of current physical activity in 844 adults (489 women). Of these, evaluated the frequency of physical activity during high school of 193 individuals,and we measured their height and weight. RESULTS: Less than 2/3 of the individuals had body mass index between 20 and 24.9 kg/m2. A tendency existed to overestimate height by less than 1 cm and to underestimate weight by less than 1kg. Desired weight was less than that reported (p<0.001), and only 20% were satisfied with their current weight. Only 42% of men and 25% of women exercised regularly. No association was found between the frequency of physical activity and the variables height, weight, and body mass index, and the level of satisfaction with current weight. CONCLUSION: Height and weight reported seem to be valid for epidemological studies, and great dissatisfaction with body weight and a distorted self-perception of height/weight ratio exists, especially in women, regardless of the frequency of physical activity.

Early Markers of Atherosclerotic Disease in Individuals with Excess Weight and Dyslipidemia

Abstract Background: Excessive weight is a cardiovascular risk factor since it generates a chronic inflammatory process that aggravates the endothelial function. Objective: To evaluate the endothelial function in individuals with excess weight and mild dyslipidemia using brachial artery flow-mediated dilation (BAFMD), and the association of endothelial function with anthropometric and biochemical variables. Methods: Cross-sectional study that included 74 individuals and evaluated anthropometric variables (body mass index [BMI], waist-hip ratio [WHR], waist circumference [AC], and percentage of body fat [PBF]), biochemical (blood glucose, insulinemia, ultrasensitive C-reactive protein, fibrinogen, total cholesterol, HDL-cholesterol, triglycerides, and LDL-cholesterol) and endothelial function (BAFMD, evaluated by ultrasound). The statistical analysis was performed with SPSS, version 16.0. To study the association between the variables, we used chi-square, Student's t and Mann-Whitney tests, and Pearson's correlation. Logistic regression analyzed the independent influence of the factors. Values of p < 0.05 were considered significant. Results: The participants had a mean age of 50.8 years, and 57% were female. BMI, WC, WHR, and PBF showed no significant association with BAFMD. The male gender (p = 0.02) and higher serum levels of fibrinogen (p = 0.02) were significantly and independently associated with a BAFMD below 8%. Conclusions: In individuals with excess weight and mild untreated dyslipidemia, male gender and higher levels of fibrinogen were independently associated with worse BAFMD.

Estudos sobrea determinação da vitamina B¹ (aneurina, tiamina) na herva mate

The infusion used as a beverage and known as tea of Paraguay or male (Ilex paraguarensis, St. Hil.) contains vitamin B (aneurin). 2) Aneurin determinations were made on the infusion commonly used (water extract) and on the complete water and alcohol extracts. The presence of aneurin was detected in both extracts. For quantitative study aneurin was adsorbed from the extracts (pH 3.8-4.0) by means of fuller's earth and kaolin. 3) Animal tests with pigeons and mice (curative, preventive and maintenance of body weight) give positive but inconstant results. No exact quantitative values could be obtained with the animal test. 4) Schopfer-Jung test based on the development of the mould « Phycomyces blakesleeanus, Bgf » showed constant results. Regular growth curves were obtained with the adsorbate of kaolin and fuller's earth. 5) The thiochrome fluorescence test introduced by Jansen was applied to the detection of aneurin in the adsorbate and good results were found which check closely with those encountered by the Schopfer-Jung test. 6) The determinations of aneurin by means of the Phycomyces and thiochrome tests gave values varying from 60 to 280 y per 100 gr. 7) Green leaves are more rich in aneurin than dry ones.

Weight loss and survival of Biomphalaria Glabrata deprived of water

Immature and mature Biomphalaria glabrata are kept out of water at relative humidities varying from 0 to 100%. When snails are submitted to a saturated atmosphere, they show a slow weight loss and survival may be long. If relative humidity (RH) decreases, weight loss becomes important and survival is short. A reduced RH (0 to 65%) produces similar effects. During desiccation, fasting has no noticeable effect; survival depends essentially on weight loss.

Influence of temperature on survival, growth and fecundity of the freshwater snail Indoplanorbis exustus (Deshayes)

To note the effect of temperature on survival, growth and fecundity, newly hatched (zero day old) snails Indoplanorbis exustus were cultured at 10 degrees, 15 degrees, 20 degrees, 25 degrees, 30 degrees and 35 degreescentigrades constant temperatures and room temperature (17.5 degrees - 32.5 degrees centigrades). Individuals exposed to 10 degrees centigrades died within 3 days while those reared at 15 degrees, 20 degrees, 25 degrees, 30 degrees, 35 degrees centigrades and room temperature survived for a period of 6, 27, 18, 16, 12 and 17 weeks respectively. An individual added on an average 0.21 mm and 0.45 mg, 0.35 mm and 7.94 mg, 0.63 mm and 15.5 mg, 0.81 mm and 27.18 mg, 1.07 mm and 41.48 mg and 0.78 mm and 31.2 mg to the shell diameter and body weight respectively at those temperatures per week. The snails cultured at 15 degrees centigrades died prior to attainment of sexual maturity. On an average, an individual produced 31.9 and 582.77, 54.86 and 902.18, 56.01 and 968.45, 49.32 and 798.68 and 62.34 and 1143.97 capsules and eggs respectively at 20 degrees, 25 degrees, 30 degrees, 35 degrees centigrades and room temperature (17.5 degrees - 32.5 degrees centigrades).

Study of the Weight of Eggs from Six Ixodid Species from Brazil

Eggs from engorged females of six ixodidae species (Ixodes loricatus, Amblyomma rotundatum, A. cajennense, Haemaphysalis leporis-palustris, Boophilus microplus, Dermacentor nitens) maintained in laboratory were counted to calculate the number and mean weight in 1g of eggs from each species. Phylogenetic considerations are discussed based on the results

Development of Rhodnius prolixus (Hemiptera: Reduviidae) under Constant and Cyclic Conditions of Temperature and Humidity

Development of Rhodnius prolixus after eclosion until the adult stage was studied at constant temperatures (T), 15, 20, 25, 28, 35°C, and relative humidities (RH), 75, 86 and 97%, and fluctuating (16/8 hr) temperatures, T I/II, 15/28°C, 20/25°C, 25/28°C and 25/35°C, and relative humidities, RH I/II, 86/75% and 97/75%. Eclosion or molting were not observed at 15°C and 86 or 97% RH, respectively. At 35°C and 75% RH only few insects molted. By alternating T I/II, 15/28°C and 25/35°C, insects developed at high frequency. Cumulating the average lengths of the interphases within independent groups for each instar, R. prolixus reached the adult stage most rapidly (86.7 days) and at highest frequency per instar (mean: 91.8%) at 28°C and 75% RH. Under fluctuating T I/II, development was completed within 100 days or less at 25/28°C and 25/35°C with high rates of hatch and molting. Development was slowest at fluctuating TI/II, 15/28°C and 20/25°C (>185 days), and at constant 20°C (>300 days). Mortality was higher at constant 97% RH or fluctuating RH I, 97%, than at constant or fluctuating 86% RH. Refeeding was minimal at optimal conditions of T and RH for development. The most refeeding was observed at a constant 35°C.

Aspects of gastrointestinal immunology and nutrition in human immunodeficiency virus-1 infection in Brazil

Mucosal surfaces have a fundamental participation in many aspects of the human immunodeficiency virus (HIV) infection pathogenesis. In Brazilian HIV-1 infected subjects, loss of weight and appetite are among the most debilitating symptoms. In this review we describe a defined mucosal immunogen that has profound but transient effects on HIV viral load, and we suggest that gut associated lymphoid tissue under constant immunostimulation is likely to provide a major contribution to the total levels of HIV. We also show that hypermetabolism appears to play a role in the wasting process in Brazilian patients coinfected with HIV and tuberculosis.

Thermal Constant of an Experimental Population of Muscina stabulans (Fallén 1817) (Diptera:Muscidae) in the Laboratory

A study was conducted to investigate the thermal constant in an experimental population of Muscina stabulans (Fallén 1817). A natural population was obtained from a livestock and their F1 generations were maintained at four constant temperatures (16°C, 20°C, 26°C and 31°C). The thermal constant was calculated by the hyperbole method using the base temperature, tb = 4.4°C and the thermal constant K = 35.3 GD. Ricker's geometric regression, considering tb = 7.8°C and K = 28.9 GD was also calculated.

What does determine gonad weight in the wild kissing bug Mepraia spinolai

Female fecundity increases with body size in a variety of insects, but it is unknown if this generalization applies for kissing bugs. In this study, we evaluate whether gonad weight in the bloodsucking insect Mepraia spinolai correlates with body size, or determined by nutrition or developmental time. We found that the investment on reproductive tissue correlates positively and significantly with body size and with the amount of ingested blood by female insects along their lifespan. Total molting time did not significantly affect gonad weight. We suggest that under optimal feeding conditions M. spinolai females could express their maximum reproductive potential.