Dietary glutamine supplementation increases the activity of peritoneal macrophages and hemopoiesis in early-weaned mice inoculated with Mycobacterium bovis bacillus Calmette-Guerin

Infants who are breast-fed have been shown to have a lower incidence of certain infectious diseases compared with formula-fed infants. Glutamine is one of the most abundant amino acids found in maternal milk and it is essential for the function of immune system cells such as macrophages. The purpose of this study was to investigate the effect of glutamine supplementation on the function of peritoneal macrophages and on hemopoiesis in early-weaned mice inoculated with Mycobacterium bovis bacillus Calmette-Guerin (BCG). Mice were wearied at 14 d of age and distributed to 2 groups and fed either a glutamine-free diet (n = 16) or a glutamine-supplemented diet (+Gln (n = 16). Both diets were isonitrogenous (with addition of a mixture of nonessential amino acids) and isocaloric. At d 21, 2 subgroups of mice (n = 16) were intraperitoneally injected with BCG and all mice were killed at d 28. Plasma, muscle and liver glutamine concentrations and muscle glutamine synthetase activity were not affected by diet or inoculation with BCG. The +GIn diet led to increased leukocyte and lymphocyte counts in the peripheral blood (P < 0.05) and granulocyte and lymphocyte counts in the bone marrow and spleen (P < 0.05). The +GIn diet increased spreading and adhesion capacities, hydrogen peroxide, nitric oxide, and tumor necrosis factor-alpha (TNF alpha) syntheses and the phagocytic and fungicidal activity of peritoneal macrophages (P < 0.05). The interaction between the +GIn diet and BCG inoculation increased the area under the curve of interleukin (IL)-1 beta and TNF alpha syntheses (P < 0.05). In conclusion, the intake of glutamine increases the function of peritoneal macrophages and hemopoiesis in early-weaned and BCG-inoculated mice. These data have important implications for the design of breast milk substitutes for human infants.

Spectrophotometric determination of fenoterol hydrobromide in pharmaceutical preparations

A simple spectrophotometric method has been developed,for the determination of fenoterol hydrobromide (FH) in tablets, drops and syrup, as the only active principle and associated with ibuprofen. The method is based on the oxidative coupling reaction of the FH with 3-methyl-2-benzothiazolinone hydrazone (MBTH) and ceric sulphate as oxidant reagent. The mixture of the drug, MBTH and ceric sulfate, in acid medium, produces a red brown color compound, with absorption maximum at 475 nm. The calibration curve was linear over a concentration range from 3.0 to 12.0 mu g/mL, with correlation coefficient of 0.9998. The different experimental parameters affecting the development and stability of the color compound were carefully studied and optimized. The method was applied successfully to assay FH in dosage forms and simulated samples. The coefficient of variation was from 0.25 % to 0.82 % and average recoveries of the standard from 98 % to 102 %. The excipients (tablets and drops) did not interfere in the analysis and the results showed that method can be used for determination of the FH isolated or associated with ibuprofen with precision, accuracy and specificity. In case of syrup, the interference in the analysis suggests a possible reaction between vehicle components with MBTH.

Development and validation of a method for quantitative determination of econazole nitrate in cream formulation by capillary zone electrophoresis

A simple, fast, inexpensive and reliable capillary zone electrophoresis (CZE) method for the determination of econazole nitrate in cream formulations has been developed and validated. Optimum conditions comprised a pH 2.5 phosphate buffer at 20 mmol L(-1) concentration, +30 kV applied voltage in a 31.5 cm x 50 mu m I.D. capillary. Direct UV detection at 200 nm led to an adequate sensitivity without interference from sample excipients. A single extraction step of the cream sample in hydrochloric acid was performed prior to injection. Imidazole (100 mu g mL(-1)) was used as internal standard. Econazole nitrate migrates in approximately 1.2 min. The analytical curve presented a coefficient of correlation of 0.9995. Detection and quantitation limits were 1.85 and 5.62 mu g mL(-1), respectively. Excellent accuracy and precision were obtained. Recoveries varied from 98.1 to 102.5% and intra- and inter-day precisions, calculated as relative standard deviation (RSD), were better than 2.0%. The proposed CZE method presented advantageous performance characteristics and it can be considered suitable for the quality control of econazole nitrate cream formulations. (c) 2008 Elsevier B.V. All rights reserved.

Microbiological Assay for Apramycin Soluble Powder

The aim of this study was to validate an agar diffusion method through the parameters linearity, precision and accuracy, to quantify apramycin in soluble powder. The calibration curve of apramycin was constructed by plotting log of concentrations (mu g ml(-1)) versus zone diameter (mm) and shows good linearity in the range of 1.0-4.0 mu g.ml(-1). The precision of the assay was determined by assaying samples at the same day (repeatability - R.S.D. = 2.00%) and on different days (intermediate precision - R.S.D. = 5.06%) and indicate good precision. The accuracy expresses the agreement between the accepted value and the value found. The mean recovery was found to be 100.49 % for apramycin soluble powder. The results indicated that the microbiological assay proposed in this work hold linearity, precision and accuracy being an acceptable alternative method for routine quality control of apramycin in the pharmaceutical dosage form studied.

In Vitro Colonic Fermentation and Glycemic Response of Different Kinds of Unripe Banana Flour

This work aimed to study the in vitro colonic fermentation profile of unavailable carbohydrates of two different kinds of unripe banana flour and to evaluate their postprandial glycemic responses. The unripe banana mass (UBM), obtained from the cooked pulp of unripe bananas (Musa acuminata, Nanico variety), and the unripe banana starch (UBS), obtained from isolated starch of unripe banana, plantain type (Musa paradisiaca) in natura, were studied. The fermentability of the flours was evaluated by different parameters, using rat inoculum, as well as the glycemic response produced after the ingestion by healthy volunteers. The flours presented high concentration of unavailable carbohydrates, which varied in the content of resistant starch, dietary fiber and indigestible fraction (IF). The in vitro colonic fermentation of the flours was high, 98% for the UBS and 75% for the UBM when expressed by the total amount of SCFA such as acetate, butyrate and propionate in relation to lactulose. The increase in the area under the glycemic curve after ingestion of the flours was 90% lower for the UBS and 40% lower for the UBM than the increase produced after bread intake. These characteristics highlight the potential of UBM and UBS as functional ingredients. However, in vivo studies are necessary in order to evaluate the possible benefic effects of the fermentation on intestinal health.

Determination of chlorpheniramine in human plasma by HPLC-ESI-MS/MS: application to a dexchlorpheniramine comparative bioavailability study

In the present study a fast, sensitive and robust validated method to quantify chlorpheniramine in human plasma using brompheniramine as internal standard (IS) is described. The analyte and the IS were extracted from plasma by LLE (diethyl ether-dichloromethane, 80:20, v/v) and analyzed by HPLC-ESI-MS/MS. Chromatographic separation was performed using a gradient of methanol from 35 to 90% with 2.5 mm NH(4)OH on a Gemini Phenomenex C(8) 5 mu m column (50 x 4.6 mm i.d.) in 5.0 min/run. The method fitted to a linear calibration curve (0.05-10 ng/mL, R > 0.9991). The precision (%CV) and accuracy ranged, respectively: intra-batch from 1.5 to 6.8% and 99.1 to 106.6%, and inter-batch from 2.4 to 9.0%, and 99.9 to 103.1%. The validated bioanalytical procedure was used to assess the comparative bioavailability in healthy volunteers of two dexchlorpheniramine 2.0 mg tablet formulations (test dexchlorpheniramine, Eurofarma, and reference Celestamine (R), Schering-Plough). The study was conducted using an open, randomized, two-period crossover design with a 2 week washout interval. Since the 90% confidence interval for C(max) and AUC ratios were all within the 80-125% interval proposed by ANVISA and FDA, it was concluded that test and reference formulations are bioequivalent concerning the rate and the extent of absorption. Copyright (C) 2009 John Wiley & Sons, Ltd.

The semi-synthetic kaurane ent-16 alpha-methoxykauran-19-oic acid induces vascular relaxation and hypotension in rats

The present work investigates the mechanisms involved in the vasorelaxant effect of ent-16 alpha-methoxykauran-19-oic acid (KA-OCH(3)), a semi-synthetic derivative obtained from the kaurane-type diterpene ent-kaur-16-en-19-oic acid (kaurenoic acid). Vascular reactivity experiments were performed in aortic rings isolated from male Wistar rats using standard muscle bath procedures. The cytosolic calcium concentration ([Ca(2+)]c) was measured by confocal microscopy using the fluorescent probe Fluo-3 AM. Blood pressure measurements were performed in conscious rats. KA-OCH(3) (10,50 and 100 mu mol/l) inhibited phenylephrine-induced contraction in either endothelium-intact or endothelium-denuded rat aortic rings. KA-OCH(3) also reduced CaCl(2)-induced contraction in a Ca(2+)-free solution containing KCl (30 mmol/l) or phenylephrine (0.1 mu mol/l). KA-OCH(3) (0.1-300 mu mol/l) concentration-dependently relaxed endothelium-intact and endothelium-denuded aortas pre-contracted with either phenylephrine or KCl, to a greater extent than kaurenoic acid. Moreover, a Ca(2+) mobilisation study showed that KA-OCH(3) (100 mu mol/l) inhibited the increase in Ca(2+) concentration in smooth muscle and endothelial cells induced by phenylephrine or KCl. Pre-incubation of intact or denuded aortic rings with N(G)-nitro-L-arginine methyl ester (L-NAME, 100 mu mol/l), 7-nitroindazole (100 mu mol/l), wortmannin (0.5 mu mol/l) and 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ 1 mu mol/l) produced a rightward displacement of the KA-OCH(3) concentration-response curve. Intravenous administration of KA-OCH(3) (1-10 mg/kg) reduced mean arterial blood pressure in normotensive rats. Collectively, our results show that KA-OCH(3) induces vascular relaxation and hypotension. The mechanisms underlying the cardiovascular actions of KA-OCH(3) involve blockade of Ca(2+) influx and activation of the NO-cGMP pathway. (C) 2011 Elsevier B.V. All rights reserved.

Evaluation of ent-Kaurenoic Acid Derivatives for their Anticariogenic Activity

Ent-kaur-16(17)-en-19-oic acid (kaurenoic acid, KA) is a tetracyclic diterpene prototype for natural anticaries agents. Six KA derivatives were prepared and their antimicrobial activity against the main microorganisms involved in the caries process evaluated. The sodium salt of KA (KA-Na) was the most active, displaying very promising MIC values for most pathogens. Time-kill assays against the primary causative agent of caries (Streptococcus mutans) indicated that KA and KA-Na only inhibited growth in the first 12 h, suggesting a bacteriostatic effect. After this period (12-24 h), their bactericidal effect was clearly noted. KA and KA-Na showed no synergy when combined with the gold standard anticariogenic (chlorhexidine dihydrochloride, CHD) in the checkerboard assays against S. mutans.

Influence of gestational diabetes mellitus on the stereoselective kinetic disposition and metabolism of labetalol in hypertensive patients

Purpose This study investigated the influence of gestational diabetes mellitus on the kinetic disposition and stereoselective metabolism of labetalol administered intravenously or orally. Methods Thirty hypertensive women during the last trimester of pregnancy were divided into four groups: non-diabetic and diabetic women treated with intravenous or oral labetalol. Results The pharmacokinetics of labetalol was not stereoselective in diabetic or non-diabetic pregnant women receiving the drug intravenously. However, oral administration of labetalol resulted in lower values of the area under the plasma concentration versus time curve (AUC) for the beta-blocker (RR) than for the other enantiomers in both diabetic and non-diabetic women. Gestational diabetes mellitus caused changes in the kinetic disposition of the labetalol stereoisomers when administered orally. The AUC values for the less potent adrenoceptor antagonist (SS) and for the alpha-blocking (SR) isomers were higher in diabetic than in non-diabetic pregnant women. Conclusions The approximately 100% higher AUC values obtained for the (SR) isomer in diabetic pregnant women treated with oral labetalol may be of clinical relevance in terms of the alpha-blocking activity of this isomer.

Biomarkers of selenium status in the amazonian context: Blood, urine and sequential hair segments

Selenium (Se) is an essential element and deficit or excess of dietary Se is associated with health disorders. Relatively elevated Se levels have been reported in the Brazilian Amazon, where there are also important annual variations in the availability of different foods. The present study was conducted among six riparian communities of the Tapajos River to evaluate seasonal variations in blood and sequential hair cm Se concentrations, and to examine the relationships between Se in blood and hair, and blood and urine. Two cross-sectional studies were conducted, at the descending water (DWS, n = 259) and the rising water (RWS, n = 137) seasons, with repeated measures for a subgroup (n = 112). Blood Se (B-Se), hair Se (H-Se) and urine Se (U-Se) were determined. Match-paired analyses were used for seasonal comparisons and the method of best fit was used to describe the relationships between biomarkers. B-Se levels presented a very large range (142-2447 mu g/l) with no overall seasonal variation (median 284 and 292 mu g/l, respectively). Sequential analysis of 13 cm hair strands showed significant variations over time: Se concentrations at the DWS were significantly lower compared with the rising water season (medians: 0.7 and 0.9 mu g/g; ranges: 0.2-4.3 mu g/g and 0.2-5.4 mu g/g, respectively). At both seasons, the relationships between B-Se and H-Se were linear and highly significant (r(2) = 67.9 and 63.6, respectively), while the relationship between B-Se and U-Se was best described by a sigmoid curve. Gender, age, education and smoking did not influence Se status or biomarker relationships. Variations in H-Se suggest that there may be seasonal availability of Se sources in local food. For populations presenting a large range and/or elevated Se exposure, sequential analyses of H-Se may provide a good reflection of variations in Se status.

Adsorption in mesopores: A molecular-continuum model with application to MCM-41

The classical model of surface layering followed by capillary condensation during adsorption in mesopores, is modified here by consideration of the adsorbate solid interaction potential. The new theory accurately predicts the capillary coexistence curve as well as pore criticality, matching that predicted by density functional theory. The model also satisfactorily predicts the isotherm for nitrogen adsorption at 77.4 K on MCM-41 material of various pore sizes, synthesized and characterized in our laboratory, including the multilayer region, using only data on the variation of condensation pressures with pore diameter. The results indicate a minimum mesopore diameter for the surface layering model to hold as 14.1 Å, below which size micropore filling must occur, and a minimum pore diameter for mechanical stability of the hemispherical meniscus during desorption as 34.2 Å. For pores in-between these two sizes reversible condensation is predicted to occur, in accord with the experimental data for nitrogen adsorption on MCM-41 at 77.4 K.

The predicate marker li in Mauritian Creole

There is a morpheme 'li' in Mauritian Creole (MC), which is homophonous with the 3sg pronoun, and which, in the early creole, occurs frequently between the subject and the predicate in affirmative, present tense clauses. I propose that that 'li' may have originated as a resumptive pronoun, co-referential with the subject, but following the grammaticalization of new determiner elements to mark the semantic contrasts of [±definite] and singular vs. plural, 'li' has now grammaticalized into a predicate marker. Its presence is sensitive to both the nature of the predicate, and to the definiteness and specificity features of the subject NP. My analysis is within the framework of Truth Conditional Semantics, where indefinite NPs are analyzed as variables that get introduced into the discourse, and must be bound by an operator to yield a closed proposition, with a truth value. Drawing on a comparison with a cognative morpheme 'i' in Seychellois Creole, I claim that its path to grammaticalization is linked to that of the specificity marking 'la'.

Separating fluorescent species of aqueous PbS semiconductor nanocrystals using micro-emulsions

Colloidal PbS nanocrystals over-coated with CdS are prepared in aqueous solutions and exhibit strong photoluminescence with two distinct peaks in the visible regime. A photoluminescence peak is observed at 640 nm, which is attributed to the band edge recombination in the PbS nanocrystals, and another peak at 510 nm, which is above the band edge of the PbS nanocrystals. The two PL peaks are isolated by extracting separate species of nanocrystal based upon their surface morphology. Micro-emulsions of hexane:PVA are used to remove the species containing the PL peak at 640 nm from the solution, leaving a singular peak at 510 nm. We show conclusively that the double-peaked structure observed in the photoluminescence spectra of PbS nanocrystals over-coated with CdS is due to the presence of two distinctly different nanocrystal species.

From possessive pronoun to emphatic determiner: 'so' in Mauritian Creole

This paper argues that at a particular stage in the genesis of Mauritian Creole (MC), the 3sg possessive pronoun 'so', inherited from the French 'son' was used as a definite determiner as well as a possessive pronoun. It was used when there was a need to single out a unique element in the discourse, or to introduce a new referent which was to become the focus of attention. 'So' was mostly used with genitive constructions, where a phonologically null determiner was equally grammatical. This paper argues that, in the early creole, genitive constructions licensed the determinative use of this pronoun. The use of 'so' with genitive constructions is no longer grammatical in modern MC, but this particle continues to be used as an emphatic determiner, where it now modifies both singular and plural NPs.

The emergence of the determiner system in Mauritian Creole: a syntax semantics mapping

This paper describes the emergence of new functional items in the Mauritian Creole noun phrase, following the collapse of the French determiner system when superstrate and substrate came into contact. The aim of the paper is to show how the new language strived to express the universal semantic contrasts of (in)definiteness and singular vs. plural. The process of grammaticalization of new functional items in the determiner system was accompanied by changes in the syntax from French to creole. An analysis within Chomsky’s Minimalist framework (1995, 2000, 2001) suggests that these changes were driven by the need to map semantic features onto the syntax.