Theoretical and Experimental Study of CaMgSi Thermoelectric Properties.

Pure CaMgSi was successfully synthesized by mechanical milling, followed by spark plasma sintering. Rietveld refinement was used to calculate the structural parameters, where a crystallite size (D XRD) of 79 nm was estimated. This value was confirmed by the Williamson-Hall analysis. Transmission electron microscopy was used to analyze the microstructure, revealing the presence of extensive interfaces, nanoparticles, and a high crystallinity. First-principles calculations were performed with the WIEN2k package, finding a band gap of 0.27 eV. The thermoelectric properties were determined combining experimental measurements and theoretical results from the BoltzTraP code. The highest value of the electronic figure of merit (ZT e) was 1.67 at 415 K. However, when the lattice thermal contribution (k L) is considered, the highest value of the figure of merit (ZT) was 0.144 at 644 K.

SHOX Duplication and Tall Stature in a Patient with Xq Deletion and Vascular Disease.

The anomalies of X chromosome are classified as numerical or structural. Concomitant structural anomalies in this chromosome that associate partial loss of its long arm with duplications in its short arm are uncommon. Only a few cases have been published and in most of them the reported patients present ovarian dysfunction, tall stature, and overdosage of the SHOX gene with locus Xp22.33. Considering these reports, we evaluated the case of a woman with a deletion in the long arm of the X chromosome, premature ovarian failure, tall stature, and multiple arterial vascular disease. With the aim to find a relationship between karyotype and phenotype, we explored associated anomalies in Xp and certified the overdosage of the SHOX gene in this case by MLPA. Also, taking into account the fact that the gene locus of the angiotensin-converting enzyme type 2 (ACE2) is located in Xp, our goal was to investigate the influence of this gene in the development of cardiovascular disease. The detection of the gene product of ACE2 by ELISA was undetectable. We have proposed that cytogenetic anomalies in X chromosome could contribute to decrease this protein synthesis in this gender.

Effectiveness and toxicity of helical tomotherapy for patients with locally recurrent nasopharyngeal carcinoma.

PURPOSE: We assessed therapeutic outcomes of reirradiation with helical tomotherapy (HT) for locoregional recurrent nasopharyngeal carcinoma (LRNPC) patients. METHODS AND MATERIALS: Treatment outcomes were evaluated retrospectively in 17 consecutive LRNPC patients receiving HT between 2006 and 2012. Median age was 57 years and most patients (n = 13) were male. Simultaneous systemic therapy was applied in 5 patients. Initial treatment covered the gross tumor volume with a median dose of 70 Gy (60-81.6 Gy). Reirradiation was confined to the local relapse region with a median dose of 63 Gy (50-70.2 Gy), resulting in a median cumulative dose of 134 Gy (122-148.2 Gy). The median time interval between initial and subsequent treatment was 42 months (11-126). RESULTS: The median follow-up for the entire cohort was 23 and 35 months for survivors. Three patients (18 %) developed both local and distant recurrences and only one patient (6 %) suffered from isolated local recurrence. Two-year actuarial DFS and LC rates were 74 and 82 %, respectively. Two-year OS rate was 79 %. Acute and late grade 2 toxicities were observed in 8 patients (47 %). No patient experienced late grade ≥3 toxicity. Late toxicity included fibrosis of skin, hypoacusia, dysphagia, and xerostomia. Patients with higher Karnofsky performance status scores associated with a lower risk of mortality (HR 0.85, p = 0.015). CONCLUSION: Reirradiation with HT in patients with LRNPC is feasible and yields encouraging results in terms of local control and overall survival with acceptable toxicity.

Effect of different nitrogen sources on plant characteristics and yield of common bean (Phaseolus vulgaris L.).

Wastewater sludge can be used to fertilize crops, especially after vermicomposting (composting with earthworms to reduce pathogens). How wastewater sludge or vermicompost affects bean (Phaseolus vulgaris L.) growth is still largely unknown. In this study the effect of different forms of N fertilizer on common bean plant characteristics and yield were investigated in a Typic Fragiudepts (sandy loam) soil under greenhouse conditions. Beans were fertilized with wastewater sludge, or wastewater sludge vermicompost, or urea, or grown in unamended soil, while plant characteristics and yield were monitored (the unamended soil had no fertilization). Yields of common bean plants cultivated in unamended soil or soil amended with urea were lower than those cultivated in wastewater sludge-amended soil. Application of vermicompost further improved plant development and increased yield compared with beans cultivated in wastewater amended soil. It was found that application of organic waste products improved growth and yield of bean plants compared to those amended with inorganic fertilizer.

Flocculant in wastewater affects dynamics of inorganic N and accelerates removal of phenanthrene and anthracene in soil.

Recycling of municipal wastewater requires treatment with flocculants, such as polyacrylamide. It is unknown how polyacrylamide in sludge affects removal of polycyclic aromatic hydrocarbons (PAH) from soil. An alkaline-saline soil and an agricultural soil were contaminated with phenanthrene and anthracene. Sludge with or without polyacrylamide was added while emission of CO(2) and concentrations of NH(4)(+), NO(3)(-), NO(2)(-), phenanthrene and anthracene were monitored in an aerobic incubation experiment. Polyacrylamide in the sludge had no effect on the production of CO(2), but it reduced the concentration of NH(4)(+), increased the concentration of NO(3)(-) in the Acolman soil and NO(2)(-) in the Texcoco soil, and increased N mineralization compared to the soil amended with sludge without polyacrylamide. After 112d, polyacrylamide accelerated the removal of anthracene from both soils and that of phenanthrene in the Acolman soil. It was found that polyacrylamide accelerated removal of phenanthrene and anthracene from soil.

Arenal, a new Leptospira serovar of serogroup Javanica, isolated from a patient in Costa Rica.

Leptospirosis is a worldwide distributed zoonotic disease caused by pathogenic spirochetes of the genus Leptospira. The basic taxon of Leptospira is the serovar. Currently, nearly 300 serovars have been identified. Leptospirosis is particularly prevalent in warm and humid tropical regions where conditions for transmission and survival of pathogenic leptospires in the environment are optimal. Leptospirosis probably constitutes a serious veterinary and public health problem in Central America but solid figures are missing. To determine distribution of leptospirosis in Costa Rica and to identify locally circulating pathogenic serovars, we performed a sentinel-based study, isolating and characterizing leptospires from patients attending hospitals. Strain MAVJ 401 was isolated from a hospitalized patient in the Alajuela province. The isolate produced agglutination titers notably with reference rabbit antisera against serovars of serogroup Javanica but appeared serologically unique in the standard Cross Agglutinin Absorption Test. Therefore, MAVJ 401 was considered to represent a new serovar, designated Arenal, of the serogroup Javanica. Genotypic analysis revealed that strain MAVJ 401 belongs to Leptospira santarosai, a species that almost exclusively occurs in Latin America. This is not a unique finding of an exotic serovar. Recent isolates from severely ill patients in the same region appeared to be identical to Arenal. We have identified a novel highly virulent serovar from a patient in Costa Rica that is common in this area, thus posing a threat for the local public and veterinary health.

A direct contact between astrocyte and vitreous body is possible in the rabbit eye due to discontinuities in the basement membrane of the retinal inner limiting membrane.

Different from most mammalian species, the optic nerve of the rabbit eye is initially formed inside the retina where myelination of the axons of the ganglion cells starts and vascularization occurs. Astrocytes are confined to these regions. The aforementioned nerve fibers known as medullated nerve fibers form two bundles that may be identified with the naked eye. The blood vessels run on the inner surface of these nerve fiber bundles (epivascularization) and, accordingly, the accompanying astrocytes lie mostly facing the vitreous body from which they are separated only by the inner limiting membrane of the retina. The arrangement of the astrocytes around blood vessels leads to the formation of structures known as glial tufts. Fragments (N = 3) or whole pieces (N = 3) of the medullated nerve fiber region of three-month-old male rabbits (Orictolagus cuniculus) were fixed in glutaraldehyde followed by osmium tetroxide, and their thin sections were examined with a transmission electron microscope. Randomly located discontinuities (up to a few micrometers long) of the basement membrane of the inner limiting membrane of the retina were observed in the glial tufts. As a consequence, a direct contact between the astrocyte plasma membrane and vitreous elements was demonstrated, making possible functional interactions such as macromolecular exchanges between this glial cell type and the components of the vitreous body.

A direct contact between astrocyte and vitreous body is possible in the rabbit eye due to discontinuities in the basement membrane of the retinal inner limiting membrane

Different from most mammalian species, the optic nerve of the rabbit eye is initially formed inside the retina where myelination of the axons of the ganglion cells starts and vascularization occurs. Astrocytes are confined to these regions. The aforementioned nerve fibers known as medullated nerve fibers form two bundles that may be identified with the naked eye. The blood vessels run on the inner surface of these nerve fiber bundles (epivascularization) and, accordingly, the accompanying astrocytes lie mostly facing the vitreous body from which they are separated only by the inner limiting membrane of the retina. The arrangement of the astrocytes around blood vessels leads to the formation of structures known as glial tufts. Fragments (N = 3) or whole pieces (N = 3) of the medullated nerve fiber region of three-month-old male rabbits (Orictolagus cuniculus) were fixed in glutaraldehyde followed by osmium tetroxide, and their thin sections were examined with a transmission electron microscope. Randomly located discontinuities (up to a few micrometers long) of the basement membrane of the inner limiting membrane of the retina were observed in the glial tufts. As a consequence, a direct contact between the astrocyte plasma membrane and vitreous elements was demonstrated, making possible functional interactions such as macromolecular exchanges between this glial cell type and the components of the vitreous body

A practical method for the radioisotope labeling of rabbit astrocytes with (3)H-thymidine.

A practical method for the radioisotope labeling aimed at the study of the proliferative behavior of astrocytes was described. It consisted in injecting 20 microCi of (3)H-thymidine into the vitreous body and tracing by autoradiography labeled astrocytes located both inside and outside the retina, e.g. optic nerve and neighboring parts of the central nervous system. The paraffin sections were immunostained for glial fibrillary acidic protein (GFAP) previous to autoradiographic processing. The semiquantitative analysis of labeled astrocytes was carried out on autoradiographs of semithin sections of rabbits killed as early as 6 h and as late as 3 months after the single intravitreal injection of (3)H-thymidine. Compared with the technique of labeling astrocytes by systemic administration (single injection or continuous infusion) of (3)H-thymidine into small animals, the method described herein has the following outstanding features: (i) it is much more economical in terms of the amount of labeled precursor used per animal; (ii) the labeling of the astrocytes is obtained as early as 6 h and remains up to 3 months after injection; (iii) the immunolabeling of the astrocytes is compatible with autoradiography; (iv) it is less risky to the experimental animal and to the environment; (v) it can be used in animals much larger than rats or mice.

Immunohistochemistry in association with scanning electron microscopy for the morphological characterization and location of astrocytes of the rabbit retina.

The purpose of the present investigation was to establish a method for the morphological characterization and location of the several types of astrocytes in the rabbit retina. Whole retinas were incubated with unlabeled antibody to glial fibrillary acidic protein (GFAP) and, afterwards, treated with secondary antibody labeled according to the requirements for the visualization of the antigen-antibody reaction either with the confocal or transmission electron microscope. Specimens treated similarly to the latter were osmium enhanced and analyzed with scanning electron microscopy (SEM). The different immunohistochemical approaches led to the conclusion that the cells selectively visualized with the SEM are astrocytes. The higher resolution and depth of focus of this instrument allowed a better morphological characterization and a more precise location of the astrocytes in the several levels of the inner portion of the rabbit retina. The method described herein, in which pre-embedding immunohistochemistry for GFAP on rabbit retinas was associated with osmium enhancement and examination with SEM, proved to be reliable and efficient for the morphological characterization and location of astrocytes.

[Toxic shock. Presentation of an obstetrical case]. / Choque tóxico. Presentación de un caso obstétrico.

The case of a 22 years old patient, primigravida, who underwent cesarean for acute fetal distress, and who presented with, at the second day of puerperium, puerperal infection, with clinical picture of shock at the third day, is presented. The clinical picture was preceded by skin rash which became a pyoderma, and ended up as desquamation; there were several alterations: hepatic, renal, hematological (disseminated intravascular coagulation) and digestive (gastroenteritis); and Staphylococcus aureus (coagulase positive) was isolated from the skin, lochia, coproculture; and they were negative to this microorganism the ones from blood, urine and pharynx. The patient received general care for her shock, steroids, blood and fresh plasma and antimicrobial agents (dicloxacillin, cefoperazone and netilmicin). Evolution was favourable, and was discharged at the eleventh day of puerperium in good conditions. A brief summary of the bibliography about this condition, and its very low incidence in our country, is pointed out, as this report is the second one in Latin American literature.