Composite Central Face Design-An Approach to Achieve Efficient Alginate Microcarriers.

Microparticulated drug delivery systems have been used as promising encapsulation systems for protecting drugs for in vitro and in vivo applications, enhancing its stability, providing an increased surface to volume ratio, reducing adverse effects, and hence an improvement in bioavailability. Among the studied microparticles, there is a rising interest in the research of alginate microparticles for pharmaceutical and biomedical fields confirming its potential to be used as an effective matrix for drug and cell delivery. Moreover, calcium alginate has been one of the most extensively forming microparticles in the presence of divalent cations providing prolonged drug release and suitable mucoadhesive properties. Regarding the above mentioned, in this research work, we intended to produce Ca-alginate micro-vehicles through electrospraying, presenting high encapsulation efficiency (EE%), reduced protein release across the time, reduced swelling effect, and high sphericity coefficient. To quickly achieve these characteristics and to perform an optimal combination among the percentage of alginate and CaCl2, design of Experiments was applied. The obtained model presented to be statistically significant (p-value < 0.05), with a coefficient of determination of 0.9207, 0.9197, 0.9499, and 0.9637 for each output (EE%, release, swelling, and sphericity, respectively). Moreover, the optimal point (4% of alginate and 6.6% of CaCl2) was successfully validated.

Mineralization of Sialoliths Investigated by Ex Vivo and In Vivo X-ray Computed Tomography.

The fraction of organic matter present affects the fragmentation behavior of sialoliths; thus, pretherapeutic information on the degree of mineralization is relevant for a correct selection of lithotripsy procedures. This work proposes a methodology for in vivo characterization of salivary calculi in the pretherapeutic context. Sialoliths were characterized in detail by X-ray computed microtomography (µCT) in combination with atomic emission spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Correlative analysis of the same specimens was performed by in vivo and ex vivo helical computed tomography (HCT) and ex vivo µCT. The mineral matter in the sialoliths consisted essentially of apatite (89 vol%) and whitlockite (11 vol%) with average density of 1.8 g/cm3. In hydrated conditions, the mineral mass prevailed with 53 ± 13 wt%, whereas the organic matter, with a density of 1.2 g/cm3, occupied 65 ± 10% of the sialoliths' volume. A quantitative relation between sialoliths mineral density and X-ray attenuation is proposed for both HCT and µCT.

Genetic diversity of standard leaf nutrients in Coffea canephora genotypes during phenological phases.

Diagnosing foliar nutritional status is essential for fertilizer recommendations and for the identification of nutrient imbalances. This study aimed to verify genetic diversity and establish mean standards (leaf nutrient contents; LNCs) and relationships among leaf nutrients (LNC relationships; LNCRs) in seven conilon coffee genotypes during both pre-flowering and bean-filling stages. Twenty crops from several cities in the northern region of Espírito Santo State, Brazil, with crop yield either equal to or greater than 100 bags per hectare (during two harvests) were assessed. A total of 140 samples were collected during each evaluation period for quantification of leaf nutrient contents (N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mn, and B). The Ward procedure, a hierarchical genetic clustering method, was used to quantify the genetic diversity among genotypes. To examine differences between the LNCs and LNCRs, F-and Scott-Knott tests were used. LNCs and LNCRs showed significant differences among the conilon coffee genotypes during the evaluation periods. Additionally, the 8V, 10V,and 12V genotypes exhibited the highest values for most of the nutrients, especially for N, P, and Cu. Therefore, the clustering method revealed genetic diversity among genotypes for standard leaf nutrient levels, implying that leaf diagnosis could be specific to each genotype and phenological stage.

Synthesis and structural analysis of a novel iodinated cyclopentadienone via ring-contraction iodination and its application in synthesis of alkyne-functionalized cyclopentadienones.

The first iodinated cyclopentadienone was isolated and its structure was confirmed by single crystal X-ray analysis. Based on this intermediate, the first direct C-C bond formation on cyclopentadienone ring was achieved. The photo induced intramolecular charge transfer of alkynylated cyclopentadienones was evaluated by solvent polarity effect on their electronic absorption spectra.

Sediment contamination of residential streams in the metropolitan Kansas City area, USA: Part I. Distribution of polycyclic aromatic hydrocarbon and pesticide-related compounds.

This is the first part of a study that evaluates the influence of nonpoint-source contaminants on the sediment quality of five streams within the metropolitan Kansas City area, central United States. Surficial sediment was collected in 2003 from 29 sites along five streams with watersheds that extend from the core of the metropolitan area to its development fringe. Sediment was analyzed for 16 polycyclic aromatic hydrocarbons (PAHs), 3 common polychlorinated biphenyl mixtures (Aroclors), and 25 pesticiderelated compounds of eight chemical classes. Multiple PAHs were detected at more than 50% of the sites, and concentrations of total PAHs ranged from 290 to 82,150 microg/kg (dry weight). The concentration and frequency of detection of PAHs increased with increasing urbanization of the residential watersheds. Four- and five-ring PAH compounds predominated the PAH composition (73-100%), especially fluoranthene and pyrene. The PAH composition profiles along with the diagnostic isomer ratios [e.g., anthracene/(anthracene + phenanthrene), 0.16 +/- 0.03; fluoranthene/(fluoranthene + pyrene), 0.55 +/- 0.01)] indicate that pyrogenic sources (i.e., coal-tar-related operations or materials and traffic-related particles) may be common PAH contributors to these residential streams. Historicaluse organochlorine insecticides and their degradates dominated the occurrences of pesticide-related compounds, with chlordane and dieldrin detected in over or nearly 50% of the samples. The occurrence of these historical organic compounds was associated with past urban applications, which may continue to be nonpoint sources replenishing local streams. Concentrations of low molecular weight (LMW; two or three rings) and high molecular weight (HMW; four to six rings) PAHs covaried along individual streams but showed dissimilar distribution patterns between the streams, while the historical pesticide-related compounds generally increased in concentration downstream. Correlations were noted between LMW and HMW PAHs for most of the streams and between historical-use organochlorine compounds and total organic carbon and clay content of sediments for one of the streams (Brush Creek). Stormwater runoff transport modes are proposed to describe how the two groups of contaminants migrated and distributed in the streambed.

Sediment contamination of residential streams in the metropolitan Kansas City area, USA: Part II. Whole-sediment toxicity to the amphipod Hyalella azteca.

This is the second part of a study that evaluates the influence of nonpoint sources on the sediment quality of five adjacent streams within the metropolitan Kansas City area, central United States. Physical, chemical, and toxicity data (Hyalella azteca 28-day whole-sediment toxicity test) for 29 samples collected in 2003 were used for this evaluation, and the potential causes for the toxic effects were explored. The sediments exhibited a low to moderate toxicity, with five samples identified as toxic to H. azteca. Metals did not likely cause the toxicity based on low concentrations of metals in the pore water and elevated concentrations of acid volatile sulfide in the sediments. Although individual polycyclic aromatic hydrocarbons (PAHs) frequently exceeded effect-based sediment quality guidelines [probable effect concentrations (PECs)], only four of the samples had a PEC quotient (PEC-Q) for total PAHs over 1.0 and only one of these four samples was identified as toxic. For the mean PEC-Q for organochlorine compounds (chlordane, dieldrin, sum DDEs), 4 of the 12 samples with a mean PEC-Q above 1.0 were toxic and 4 of the 8 samples with a mean PEC-Q above 3.0 were toxic. Additionally, four of eight samples were toxic, with a mean PEC-Q above 1.0 based on metals, PAHs, polychlorinated biphenyls (PCBs), and organochlorine pesticides. The increase in the incidence of toxicity with the increase in the mean PEC-Q based on organochlorine pesticides or based on metals, PAHs, PCBs, and organochlorine pesticides suggests that organochlorine pesticides might have contributed to the observed toxicity and that the use of a mean PEC-Q, rather than PEC-Qs for individual compounds, might be more informative in predicting toxic effects. Our study shows that stream sediments subject to predominant nonpoint sources contamination can be toxic and that many factors, including analysis of a full suite of PAHs and pesticides of both past and present urban applications and the origins of these organic compounds, are important to identify the causes of toxicity.

Further developments in determining the number of resonance structures in benzenoid free radicals: analytical expressions and elementary substructures.

Relationships for counting the number of resonance structures (SC) of benzenoid free radicals are discussed. The structural origin of some of the coefficients to the SC analytical expressions for series of benzenoid free radicals generated by successive attachment of specific aufbau units is determined. It is shown that a proper pruning fragment for the purpose of a priori determination of the coefficient in the highest degree n term of the SC analytical expression belonging to a given radical series has the property of bond fixation when the operation is performed on every member of that series, resulting in all remnant structures having the same SC value.

Determining the number of resonance structures in concealed non-Kekuléan benzenoid hydrocarbons.

The number of resonance structures (SC) for previously published concealed non-Kekuléan benzenoid hydrocarbons is determined. Using a simple computer program, analytical expressions for determining SC for various classes of non-Kekuléan (free-radical) benzenoid hydrocarbons are derived, and some properties of concealed non-Kekuléan benzenoid hydrocarbons are studied.

13C nuclear magnetic resonance data of bile acid derivatives.

The 13C-NMR spectra of well over 100 bile acid derivatives have been analyzed and summarized. A diagnostic gamma-oxygen shielding effect has been identified.

[Urological clinical semeiology]. / Semiologia clínica urológica.

The authors review all symptoms and signs in the urological field, as well as definitions, characteristics and pathological significance according to current knowledge.

Percutaneous sclerotherapy of varicocele.

Percutaneous sclerotherapy of varicocele was considered in 21 patients with left sided varicocele, 16 of whom had recurrences after left spermatic vein ligation in the past. Percutaneous sclerotherapy was possible in 17 patients (80.9%). There were no serious complications with venography or sclerotherapy, and the recurrence rate was 17.6%. Percutaneous sclerotherapy is therefore a simple, safe and effective treatment of testicular vein insufficiency.

Mass spectral fragmentation of 24,24-diphenyl-23-ene derivatives of cholic acid.

After electron impact in the mass spectrometer, 24,24-diphenyl-23-ene derivatives of cholic acid ejected the 17-sidechain as an ionized 1,1-diphenyl-butadiene derivative, and the 12 alpha-acetoxy group activated this loss. This contrasts markedly with the mass spectrometric fragmentation of typical sterols having unsaturated 17-sidechains that are also devoid of functionality on the C-ring.

Studies directed toward synthesis of quassinoids VII. Conversion of chenodeoxycholic acid to a delta-lactone quassinoid analog and generation of A-ring diosphenol acetate derivatives of deoxycholic acid.

Chenodeoxycholic acid was converted to a new 5,14-epi-28,30-dinorquassinoid analog. Two isomeric A-ring diosphenol acetate derivatives of deoxycholic acid were synthesized. A 3-oxo-5 beta-steroid was transformed to a 4-acetoxy-3-oxo-delta 4-steroid by treatment with base and oxygen or to a 2-acetoxy-3-oxo-delta 2-steroid by reaction with cupric chloride in refluxing acetic acid followed by acetylation. Ketene extrusion is a characteristic mass spectral fragmentation of these diosphenol acetates.