Reproducibility of manual choroidal thickness measurements using optical coherence tomography. / Reproducibilidad de la medición manual del grosor coroideo utilizando la tomografía de coherencia óptica.

PURPOSE: Spectral-domain optical coherence tomography (SD-OCT) is the most useful tool to measure choroidal thickness (CT). CT may be increased in ocular and systemic diseases. However, there are concerns relating reproducibility and external validity of OCT. The aim of this study was to assess the inter-observer and intra-observer variability of manual OCT measurements. METHODS: CT was manually measured in the central choroid of 40 eyes from 21 subjects (11 healthy and 10 with ankylosing spondylitis) using RTVue-100 OCT (Optovue Inc., Fremont, CA, EE.UU.). Measurements were performed by 9 independent ophthalmologists from 6 different centers. To assess the inter-observer variability, the intra-class correlation coefficient (ICC) method was calculated. Also, intra-observer variability was assessed in 2 of the ophthalmologists. RESULTS: The mean subfoveal CT was 364.9±85.1µm (range, 170 to 572). The inter-observer ICC was 0.823 (CI 95%, 0.749 to 0.888, p<0.001). The intra-observer ICCs were 0.885 (CI 95%, 0.783 to 0.939, p<0.001) and 0.925 (CI 95%, 0.859 to 0.960. p<0.001). CONCLUSIONS: In this study, manual measurements of CT with OCT showed a good concordance. These results suggest that manual OCT is a valid tool for multicenter studies.

Enzyme mediated synthesis of polypyrrole in the presence of chondroitin sulfate and redox mediators of natural origin.

Polypyrrole (PPy) was synthesized by enzyme mediated oxidation of pyrrole using naturally occurring compounds as redox mediators. The catalytic mechanism is an enzymatic cascade reaction in which hydrogen peroxide is the oxidizer and soybean peroxidase, in the presence of acetosyringone, syringaldehyde or vanillin, acts as a natural catalysts. The effect of the initial reaction composition on the polymerization yield and electrical conductivity of PPy was analyzed. Morphology of the PPy particles was studied by scanning electron microscopy and transmission electron microscopy whereas the chemical structure was studied by X-ray photoelectron and Fourier transformed infrared spectroscopic techniques. The redox mediators increased the polymerization yield without a significant modification of the electronic structure of PPy. The highest conductivity of PPy was reached when chondroitin sulfate was used simultaneously as dopant and template during pyrrole polymerization. Electroactive properties of PPy obtained from natural precursors were successfully used in the amperometric quantification of uric acid concentrations. PPy increases the amperometric sensitivity of carbon nanotube screen-printed electrodes toward uric acid detection.

Preparation and Characterization of Coaxial Electrospun Fibers Containing Triclosan for Comparative Study of Release Properties with Amoxicillin and Epicatechin.

The optimal conditions for the fibers preparation of cellulose acetate (CA) and poly(vinyl pyrrolidone) (PVP) containing triclosan within the fiber were successfully found; the physicochemical characteristics of these fibrous membranes were corroborated by FTIR spectroscopy, thermal analysis, mechanical tests, SEM , and TEM analysis. The formation of composite fibers of CA and PVP containing triclosan at the core of the fiber was evidenced. A comparative study of the release properties of amoxicillin, epicatechin or triclosan embedded into fibers CA/PVP/CA was performed. As more interactions of the drug with CA or PVP occur, slower release of the drug into the release medium takes place. Regarding the drug delivery system design, it is important to consider the possible molecular interactions between the material components and predict how fast or slow the drug will be delivered into the corresponding medium.

Preparation by coaxial electrospinning and characterization of membranes releasing (-) epicatechin as scaffold for tissue engineering.

Optimal conditions for the preparation of a composite material of fibers of cellulose acetate (CA) and poly(vinyl pyrrolidone) (PVP), containing epicatechin (Epic) within the fiber CA/PVP-Epic/CA, were found. The morphology and physical/chemical properties of the fibrous membranes containing CA, PVP, and epicatechin were characterized using FTIR spectroscopy, thermal analysis, SEM, TEM, and natural weathering. Also, mechanical characterization of the fibers showed that tensile strength of the membrane was not affected by the presence of epicatechin within the fiber as compared with fibers without epicatechin. The effect of the medium on the release rate of epicatechin was also studied. The amount of epicatechin release was higher in water, 79.6%, and 31% in MesenCult medium. These results showed that these composite materials are recommended for cardiac tissue engineering; furthermore, using these materials allows precise release of the epicatechin in the damaged tissue.

Extruded films of blended chitosan, low density polyethylene and ethylene acrylic acid.

The obtaining of chitosan extruded films was possible by using low density polyethylene (LDPE) as a matrix polymer and ethylene-acrylic acid copolymer as an adhesive, in order to ensure adhesion in the interphase of the immiscible polymers. The obtained blend films were resistant; however, a reduction in the mechanical resistance was observed as chitosan concentration increased. The thermal stability of the films showed a certain grade of interaction between polymers as seen in FTIR spectra. The antifungal activity of the extruded films was assessed against Aspergillus niger and high inhibition percentages were observed, which may be mainly attributed to barrier properties of the extruded films and the limited oxygen availability, resulting in the inability of the fungi to grow. A low adherence of fungal spores to the material surface was observed, mainly in areas with chitosan clumps, which can serve as starting points for material degradation.

A possible role of the P53 gene deletion as a prognostic factor in multiple myeloma.

The role of P53 gene abnormalities in the pathogenesis of multiple myeloma (MM) and their potential use as prognostic indicators remain uncertain. To further define this question, we studied genomic DNA from 50 MM and one plasma cell leukemia patients by polymerase chain reaction single-strand conformation polymorphism and sequencing, and fluorescence in situ hybridization in order to detect P53 mutation and deletion, respectively. Kaplan-Meier survival curves and the log-rank test were used to analyze the survival data. No P53 mutation was detected in our patients. In contrast, P53 deletion, predominantly monoallelic, was detected in 8 of 51 (15.7%) patients. Similar frequencies of P53 deletion were observed in patients stratified by age ( P=0.71), gender ( P=0.44), status, and stage of the disease ( P=0.70 and P=0.23, respectively). However, patients with P53 deletion had significantly shorter median overall survival compared with those without a deletion (7.4 vs 139.0 months, P<0.0001). On univariate regression analysis, P53 deletion was a parameter for predicting shortened survival ( P=0.02). We concluded that P53 mutation may be seen as a prognostic indicator of limited value in MM. In contrast, P53 deletion may be seen as a prognostic indicator of poor outcome. However, as the cohort of patients is rather limited for a prognostic analysis, these results should be confirmed by further studies with larger sized samples.

Kinetic characterization of bovine lung low-molecular-weight protein tyrosine phosphatase.

Protein tyrosine phosphatase is an important class of enzymes that plays an essential role in the cellular proliferation, differentiation, and oncogenesis. In this paper we report characterization of a low-molecular-weight protein tyrosine phosphatase purified from bovine lung. The enzyme activity was essentially independent of metal ions and sensitive to sulfhydryl reagents. Both vanadate and inorganic phosphate are competitive inhibitors, with Ki values of 0.38 microM and 0.28 mM, respectively. Besides p-nitrophenyl phosphate, the enzyme was also able to efficiently hydrolyze tyrosine phosphate, beta-naphthyl phosphate, and flavine mononucleotide.

[Metabolic effects of exposure to air and the post-aeration response in the intertidal anthozoan Actinia equina L]. / Efectos metabólicos de la exposición al aire y respuesta postaérea en el antozoo intermareal Actinia equina L.

Metabolic adjustments occurring during air exposure have been studied in a population of Actinia equina submitted to long-lasting emersion periods. Oxygen consumption upon reimmersion seems to account for the discharge of an oxygen debt related to the accumulation of end-products derived from anaerobic pathways. Incorporation of radioactive labelled glucose into both submerged and air exposed animals has allowed identification of these final products. A correspondence between the length of exposure-time and the amount of oxygen debt is encountered, which parallels the evolution of the rate of radioactivity incorporation into amino acids. Increasing levels of amino acid synthesis from glucose in the exposed conditions appear as the main metabolic feature.

[Considerations on a population policy for the Dominican Republic]. / Consideraciones acerca de una politica de poblacion para Republica Dominicana

PIP: The author discusses the development of a population policy for the Dominican Republic. The concept of such a policy is considered, with a focus on whether the policy should be associated with programs of action and whether it should address only the issue of population growth or should consider other demographic factors as well. Recommendations for designing a population policy are included.^ieng

[Women and employment: an examination of the relation between types of employment and family formation]. / Mujeres, y empleo: un examen de la relacion entre tipos de empleo y formacion de la familia.

PIP: Preliminary results concerning commitment to work and the impact of female employment on fertility from a larger survey carried out in 1978 among women aged 20-39 years in the Dominican Republic are presented. In 1970, 27% of women aged 10 or over were economically active; the increase in participation between 1960-70 affected all age groups but was particularly intense among women aged 20-39, who had a rate of nearly 35% in 1970. 33% of the surveyed women reported themselves as economically active in 1978. Another 31% had previously been employed but were no longer working. 41% of those not working had sought employment within the previous year. The survey indicated a significant change in the educational status of the women. 29.3% of women aged 20-24 years had attended or were attending university, compared to 22.1%, 6.6%, and 4.0% in the 3 older cohorts. 20.8% of the respondents were professionals, 25.8% were office workers, 6.8% were in commerce, 9.4% were factory workers, 19.2% were nondomestic service workers, 15.0% were domestic workers, and 1.2% were administrators, functionaries, or large proprietors. Administrators and functionaries had the highest salaries, followed by office workers. Although domestic workers earned low salaries, they declared a higher level of job satisfaction than any other group. Factory workers reported the lowest level of job satisfaction. 17% fewer of the married than the nonmarried workers wished to continue working 5 years into the future, and nondomestic workers had a greater likelihood of continuing work than did domestics. Education of the respondent and her father appeared to be positively related to employment. Age and marriage were negatively related to employment. In the sphere of decision making, younger women, educated women, and employed women were significantly more likely to report joint decision making with the spouse. Regressions of fertility and 2 indicators of marital status on 7 occupational categories and the control variables explained 47% of the variance in fertility, 26% of the variance in the number presently married, and 34% in those married at some time. Fertility was strongly related to education and occupational status. Administrators and functionaries had 2.02 fewer children than those not working; only office workers and professionals also had lower fertility than those not working. Fertility of service workers and those in commerce was significantly higher than that of the nonemployed.^ieng

[Elements of a better understanding and evaluation of population policy in the Dominican Republic]. / Elementos para una mejor comprension y evaluacion de la politica poblacional de la Republica Dominicana.

PIP: This work has 3 objectives: to clarify the concept of population policy, to examine different theoretical approaches to the analysis of a national population policy, and to describe the origin, development, and present characteristics of the population policy of the Dominican Republic. The concept of population policy is often confused with the related concepts of responsible parenthood, family planning, and birth or population control. Population policy may be defined as a coherent group of declarations, decisions, and actions following a rational strategy which, as part of a national development plan, is formulated and implemented by the state and additional social institutions in accordance with national needs. Its final goal is the protection and development of human resources through influencing population characteristics. Although recent attempts to apply the methods of political analysis to the area of population policy all suffer from limitations, 4 frameworks which respectively look at the 3 levels of population policy (the philosophic-ideologic, the scientific, and the practical); at the division of population policy into declarations, decisions, programs, and results; at criteria for evaluating the probability of success of a population policy; and at the stages of development of population policies in dependent countries can be of assistance in understanding and evaluating the population policy of the Dominican Republic. Until 1961, the end of the Trujillo era, a pronatalist attitude predominated in the Dominican Republic, prompted in part by fears of an aggressive and densely populated Haiti sharing the same island. From 1962-66, a gradual change in attitudes began in the private sector as various groups began quiet efforts at family planning and the Dominican Association for Family Welfare was formed and became an affiliate of the International Planned Parenthood Federation. During this stage the government remained neutral or offered quiet support, such as allowing tax-free importation of contraceptives. In the next stage, the government became more concerned with the population problem, culminating in the incorporation of free family planning services into the maternal-child health program. In the 4th stage of development, from 1968-73, a national family planning program was created according to a 5-Year Plan covering 1969-73 whose goal was a birth rate decline from 48/1000 in 1969 to 38/1000 by 1973. In the 5th stage, financial and technical aid from the Population Council was augmented by a closer link to UNFPA.^ieng