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The main aim of the present study was to synthetize polyacrylamide nanoparticles and to use them as photosensitizer carriers. The new monobrominated derivatives (monobrominated neutral red and monobrominated azure B) were the photosensitizers used for antimicrobial photodynamic therapy. They were loaded into the nanocarriers and their antibacterial and oxidative activities were evaluated. The polyacrylamide nanoparticles were evaluated and prepared by inverse microemulsion polymerization. The nanoparticles obtained were characterized by size, polydispersity index, and zeta potential analysis. The Dynamic Light Scattering indicated that the diameter of the particle (z-average) was optimal, with an acceptable polydispersity index. The antibacterial activity of the polyacrylamide nanoparticles loaded with photosensitizers was evaluated against Staphylococcus aureus. Both photosensitizers loaded into the nanoparticles showed great potential as antibacterial agents since they suppressed the bacterial growth. The maximum percentage of growth reduction was 35.5% (>2 Log CFU/mL), with the monobrominated azure B loaded into the nanocarrier with 2 hydroxyethyl methacrylate against methicillin resistant S. aureus. The improved physicochemical and photophysical properties of these photosensitizers were accompanied by a significant increase in the photoantimicrobial action, in conventional-sensitive and-methicillin resistant S. aureus. The results obtained clearly suggest that polyacrylamide nanoparticles loaded with photosensitizers have great potential for further application in antimicrobial photodynamic therapy.

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At present, polyacrylamide nanoparticles are attractive to drug delivery. However, some physicochemical characteristics of these nanoparticles still need to be further improved in practice. Polyacrylamide nanoparticles with an average size of 80nm and a zeta potential of -30mV were synthesized and used as photosensitizer carriers. The new monobrominated derivatives and parent compounds were the photosensitizers for the photodynamic therapy loaded in the nanocarrier. The physicochemical characterization of the prepared nanoparticles, drug loading, the ability to generate singlet oxygen and chemical stability were investigated. The novel tested nanoparticles exhibited a loading percentage of between 80 and 99%, higher generation of singlet oxygen and good stability in comparison with the corresponding starting reagent. According to these results, the novel polyacrylamide nanoparticles are excellent candidates for drug vehiculization.

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We report herein the synthesis, and the physicochemical and pharmacokinetic properties of N-acyloxymethyl prodrugs of allopurinol (Allop) (2a-f). Allop is a compound with activity against Trypanosoma cruzi, a causative agent of Chagas disease. Its pathology leads to a huge number of infections and deaths per year, because in addition to many sufferers only having limited access to health services only an inefficient chemotherapy is available. Relevant pharmaceutical properties (pKa, stability, solubility, lipophilicity, in vitro permeability, binding protein, xanthine oxidase binding) were also determined. The results obtained showed that derivatives behave as prodrugs of Allop, since they exhibit improved physicochemical and pharmacokinetic properties relative to their precursor. This behavior turns these compounds into active reservoirs of Allop, and reduces its unfavorable characteristics, so 2a-f compounds are excellent candidates for the treatment of Chagas disease. This work is therefore an important contribution leading to the suppression of Chagas disease.

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Cresyl violet and cresyl red, components of commercial cresyl violet acetate, were separated and purified using preparative column liquid chromatography. The stationary phase was silica gel and gradient elution was carried out using chloroform:methanol. The purified dyes were obtained in high yield; 51% of the original lot was recovered as cresyl violet and 40% as cresyl red. Separated materials were characterized by nuclear magnetic resonance and mass spectroscopy; UV-visible and Fourier-transform infrared spectra also were obtained for samples of pure cresyl violet and cresyl red. The colored constituents of the commercial dye lot were identified using thin layer chromatography and reverse phase high performance liquid chromatography. Both methodologies were suitable for routine testing; reverse phase high performance liquid chromatography is an appropriate tool for quality control and high resolution identification of these compounds.

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A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis.

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The goal of this study was to determine the kinetic parameters involved in the decomposition of 2-(5-methyl-4-isoxazolylamino)-N-(5-methyl-4-isoxazolyl)-1,4-naphthoquinone-4-imine (1) in aqueous solution and to identify the main degradation products. An isocratic HPLC assay was used to study the degradation rate of 1. The products of hydrolysis were identified by comparison of their retention times with those of authentic samples. The amount of 1 and the two degradation products resulting from storage of 1 in various buffer solutions was followed in function of time by a reversed-phase HPLC stability-indicating method. The observed degradation rates followed pseudo-first-order kinetics at constant pH, temperature and ionic strength. The logk-pH-profile was constructed at 35 degrees C from the first-order rate constants obtained from studies at pH values ranging from 0.88 to 10.80 (mu=0.5 M). Hydrolysis in the acidic and alkaline media resulted in the formation of two degradation products in each case. The pH-rate profile of 1 in buffer solution was adequately described using a four-term rate equation. The obtained pH-rate profile indicated specific acid-base catalysis with a region of maximum stability between pH 6.40 and 7.40 which can be adequate for formulations of 1.

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In the last years, the adherence adnexal disease has been increased due to pelvic infections. This may cause infertility problems depending, of the nature, extension and localization inside the pelvis. In this paper we inform the results obtained in 70 patients with adnexal adhesions to whom it was performed a salpingo-ovariolysis with microsurgery technology, with the purpose of promote the fertility. All the patients received pre, trans and postoperative support (Heparin, steroids and antimicrobials). The minimal time of postoperative observation was at least 6 months. In 27 (Group I) of the 70 cases (38.6%), the adherences were avascular (IA & IIA based on Hulka's classification); and in the 43 patients of the group II (61.4%), the lesions were dense and vascular (IB & IIB). In group I, 15 pregnancies were obtained (55.6%), 13 at term, 1 miscarriage and 1 ectopic pregnancy; in the group II we documented 9 pregnancies (20.9%), 5 at term, 4 miscarriage (I trimester).

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The kinetics of enolization and degradation of N-(5-methyl-4-isoxazolyl)-4-amino-1,2-naphthoquinone (1) was investigated in aqueous solutions over a pH range of 7.30 to 12.25, at 35 degrees C and at constant ionic strength (mu = 0.5) using reversed-phase HPLC. Pseudo-first-order kinetics was observed throughout the pH range studied. The rate of enolization (ke), the keto-enol equilibrium constant (Kt), and specific base catalysis rate constant (kCH) were determined. Good agreement between the theoretical pH-rate profile and the experimental data supports the proposed transformation process. The average recovery for 1 and its tautomerization product 2-hydroxy-N-(5-methyl-4-isoxazolyl)-1,4-naphthoquinone 4-imine (2) from mixtures of different composition was evaluated.

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The degradation kinetics of N-(5-methyl-4-isoxazolyl)-4-amino-1,2-naphthoquinone (1) was studied in aqueous solution over a pH range of 0.65-7.50, at 35 degrees C and at a constant ionic strength of 0.5. The degradation rates were determined by high-pressure liquid chromatography and were observed to follow pseudo-first-order kinetics with respect to the concentration of 1. The pH-rate profile was linear with slope -1 under acidic pH, becoming pH independent from 3.50 to 7.50. Good agreement between the theoretical pH-rate profile and the experimental data supports the proposed degradation process. The catalytic rate constants for hydrogen ion and water were kH = 0.901 M-1 h-1 and k0 = 1.34 x 10(-3)h-1, respectively. These data are appropriate to develop a stable dosage form of 1. The accuracy, peak sharpness, and asymmetry factor for the analytical method were determined.

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This is a study using light microscopy and electronic microscopy of Fallopian tube subjected to sterilization; and compare it with a control group. A total of 60 samples from patients with different surgical procedures, whose age was from 20 to 40 years; they were amenorrheic, without antecedents of pelvic inflammatory disease nor endometriosis. Among the control group, there were lesions as isthsmical nodular salpingitis in 30.7%. There was chronic salpingitis in 15.3%; follicular salpingitis in 23%, and polyps in 15%. In the group with OTB antecedents, endosalpingiosis was found in 20%; follicular salpingitis in 30% and chronic salpingitis in the remaining 50%. By means of electronic, ultrastructural microscopy, were seen lesions at myosalpinx level, that is, alterations in myofilaments, formation, much fibrosis and descilliation in the adjacent to OTB. It may be concluded that these findings, never seen before, may condition an alteration of tubal motility in patients subjected to rechannelization procedures, that condition an alteration in gametes transportation, avoiding fecundation or a greater incidence ectopic pregnancy incidence.

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