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Microemulsions (MEs) were designed by an innovative rational development, characterized, and used to load up to 20 mM of Tamoxifen citrate (TMX). They were made with acceptable and well-characterized excipients for all the routes of administration. Some of their properties, such as nanometric mean size and long stability shelf life, make them interesting drug delivery systems. The results obtained after the in vitro inhibition of estradiol-induced proliferation in MCF-7 breast cancer cells demonstrated a significant effect in cell growth. A decreasing of at least 90% in viable cells was shown after the incubation with MEs containing 20 mM of TMX. Besides, two compositions which loaded 10 mM of drug showed a cytotoxic effect higher than 70%. These results encourage the evaluation of alternative protocols for this drug administration, not only for estrogen receptor (ER) positive tumors, but also for ER negative.

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OBJECTIVE: Two carvedilol aqueous solutions and one carvedilol aqueous suspension for paediatric oral use (1mg/ml) were studied to determine their stability. METHOD: All samples were stored at 4, 25 and 40°C. Carvedilol content of each of the three formulations was tested using high performance liquid chromatography (HPLC). Each sample was analysed in triplicate at 0, 3, 7, 14, 28 and 56 days. RESULTS: Carvedilol stayed stable in the acidic aqueous solution at the three different temperatures during the 56 days of the study. In the alkaline solution, carvedilol was stable during 56 days at 25°C, but only 28 days at 4 and 40°C. In the aqueous suspension, carvedilol was stable during 56 days at 4 and 25°C, but only 28 days at 40°C. CONCLUSIONS: All the formulations that were tested can be stored at 25°C for at least 56 days.

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In this article a detailed revision of the therapeutic applications of the calcium salts of most frequent use, is made. The metabolism, the bioavailability and the clinical use of the different calcium formulations vary significantly according to the salt used. The physiologic order factors, the physicochemical, the technological and the formulation ones influence in the bioavailability and, they alter the therapeutic answer. The salts of most frequent use, carbonate, citrate, pidolate, dobesilate, gluconate, phosphate and lactate, contribute in different quantities of elementary calcium. Recent studies show significant data that can be of importance in the clinical practice. The most habitual uses in the calcium salts are: for the osteoporosis treatment and prevention; in osteopenia; in hypocalcemia states; for low contribution or had absorption; as dietary supplement, according to the recommended daily ingesta and also, in vascular illnesses, like in internal hemorrhoids, phlebopathy and in diabetic retinopathy. It is concluded that it is fundamental to contribute the appropriate quantity of calcium according to the individual requirements and, on that base, to select the appropriate formula keeping in mind the variability that takes place in the absorption in connection with the salt used.

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Quaternary microemulsion compositions for oral administration using isopropyl myristate, polysorbate 80 and ethanol 96 degrees were developed and three ratio of polysorbate to ethanol were selected. Isotropic single-phase compositions were considered as microemulsions and were registered on a Pseudo-Ternary Phase Diagram. The objective was to formulate a therapeutic dose for lorazepam and loperamide in a drop liquid form. Another aim was to obtain a liquid oral formula for nifedipine taking advantage of its insured fast absorption to be used in hypertensive crises. The physical stability of the compositions was evaluated by normal aging, centrifugal resistance time and by cycling as well. The selected formulation characterization included density, pH and conductivity measurements. The particle size distribution was determined by a light scattering method and, finally the carried drugs concentration was valued. The versatility showed by this type of systems allows both to carry drugs of different physico-chemical properties and to deal with a number of pharmacotherapeutic objectives.

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Microspheres of Bacillus subtilis were prepared using sodium alginate. Some typical properties of microencapsulated systems, such as microorganism content, particle size, and germination time, were studied. Calcium alginate microspheres were obtained by the emulsification method, dripping into a solution of calcium salt. The conditions of the preparation steps were very soft to produce calcium alginate microspheres containing cells with no apparent changes in general biological properties. The hydrogel matrix provides protection without preventing communication with the surrounding medium.

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Semen rheology was studied to elucidate the biochemical basis of seminal plasma hyperviscosity. Semen proved to fit in with a power law model, by presenting a pseudoplastic behavior. Apparent viscosity at 230 s(-1) and 25 degrees C (eta(a)) was 4.3 /- 0.2 cp and 5.4 +/- 0.4 cp in normal and high-consistency semen, respectively. The effect of enzymes and mucolytic agents on human seminal plasma viscosity were evaluated by incubating normal and hyperviscous semen pool aliquots with trypsin, dithiothreitol, EDTA, alpha-amylase and deoxyribonuclease I. After incubation, trypsin treatment reduced eta(a) by 36% in normal semen and by 44% in hyperviscous semen. There was a decrease in eta(a) following incubation of hyperviscous samples with dithiothreitol (33%) and alpha-amylase (44%) that was not observed in the normal consistency samples. No decrease was observed in eta(a) after EDTA or DNAse treatment of both groups. Comparison of normal and hyperviscous seminal plasmas revealed no difference in the concentration of total proteins, DNA, or in the percentage of water content. These findings indicate that the primary substances responsible for basic normal semen rheologic behavior are proteins. A comparison of rheological properties between normal and hyperviscous semen samples indicates the existence of a highly organized network in the latter group, in which disulfide bonds and oligosaccharide chains complexed to the peptide core may play a key role.

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The production of polymeric complexes in many active drugs with reticulated povidone increased dissolved component percentage. In this work made use a coevaporation technique. Complex formation has been tested by X Ray Diffractometry and Differential Scanning Calorimetry. The percentage of dissolution was determined to the USP XXIII Edition methodology. As can be seen from the results, the Atenolol-reticulated Povidone complexes has greater solubility than the Atenolol mixed with Lactose as excipient.

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Seminal hyperviscosity is generally thought to reveal genitourinary infection. The aim of the present work was to study this hypothesis. A total of 65 semen samples were obtained from males presenting for infertility screening. The samples were evaluated according to WHO criteria and microbiologically investigated, including culturing for Mycoplasma hominis and Ureaplasma urealyticum, and microscopic observation of Chlamydia trachomatis by a direct fluorescence assay. Determination of local antisperm antibodies was performed. Semen was categorized according to consistency: normal (n = 31) and high (n = 34). No difference was recorded either in the number of positive cultures, or in the number of species found in each sample. The number of white blood cells and the percentage of antibody-bound sperm showed no difference in the groups under study. There was no association between seminal hyperviscosity, positivity in semen cultures, number of species isolated in semen cultures, leukospermia, or presence of sperm antibodies. Further studies should be performed considering the evolution of the genital-infected patients to clarify the etiology of the hyperviscosity.

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It is done a comparative study between the "Recommended rules for drug products manufacturing and inspection", approved in 1975 by the World Health Organization (and still in force in the MERCOSUR); and the standards published in 1992 by the WHO Expert Committee on Specifications for Pharmaceutical Preparations 32nd Report, named "Good Manufacturing Practices for pharmaceutical products". The correspondence between the regulation in force in the MERCOSUR and the Good Manufacturing Practices Inspection Guide for pharmaceutical industry, used by Health Authorities in the Common Market Member States, is analysed. It is noticed a disagreement between the rule in force and the instrument for verifying its fulfillment. The proposal of this article is the adoption by the Common Market Group, of the rules published by the WHO in 1992, and the establishment of an inspection guide which absolute agrees with it.

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Objective spermatic motility (Hamilton Thorne Research), the rapid progressive spermatozoa (grade A) recovery after swim-up, and the spermatozoa ATP content (bioluminescence) were studied in normoviscous and hyperviscous asthenospermic samples. The amplitude of lateral head displacement (ALH) was significantly lower in hyperviscous semen (normal: 4.6 +/- 0.7 microns [n = 20], high: 3.5 +/- 1.2 microns [n = 16]; p < .05). The grade A recovery percentage after swim-up was significantly higher in semens with high consistency (normal: 71.0 +/- 38.0 [n = 14], high: 181.3 +/- 108.9 [n = 6]; p < .05). The ATP content per living spermatozoa was in the normal consistency group 449.4 +/- 65.1 pmol per million living spermatozoa (n = 29) and in the high consistency batch 605.1 +/- 242.8 (n = 9), p < .05. In asthenospermia, the spermatozoa from hyperviscous samples have minor ALH values, better response to swim-up, and high ATP content than those from normoviscous ejaculates.

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