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Globules
Kinds of Globules Terms modified by Globules Selected AbstractsStepwise proteolytic removal of the , subdomain in ,-lactalbuminFEBS JOURNAL, Issue 15 2001The protein remains folded, can form the molten globule in acid solution Bovine ,-lactalbumin (,-LA) is an ,/, protein which adopts partly folded states when dissolved at low pH (A-state), by removal of the protein-bound calcium at neutral pH and low salt concentration (apo-state), as well as in aqueous trifluoroethanol. Previous spectroscopic studies have indicated that the A-state of ,-LA at pH 2.0, considered a prototype molten globule, has a native-like fold in which the helical core is mostly retained, while the , subdomain is less structured. Here, we investigate the conformational features of three derivatives of ,-LA characterized by a single peptide bond fission or a deletion of 12 or 19/22 amino-acid residues of the , subdomain of the native protein (approximately from residue 34 to 57). These ,-LA derivatives were obtained by limited proteolysis of the protein in its partly folded state(s). A nicked ,-LA species consisting of fragments 1-,3,40 and 41,123 (nicked-LA) was prepared by thermolytic digestion of the 123-residue chain of ,-LA in 50% (v/v) aqueous trifluoroethanol. Two truncated or gapped protein species given by fragments 1,40 and 53,123 (des,1-LA) or fragments 1,34 and 54-,57,123 (des,2-LA) were obtained by digestion of ,-LA with pepsin in acid or with proteinase K at neutral pH in its apo-state, respectively. The two protein fragments of nicked or gapped ,-LA are covalently linked by the four disulfide bridges of the native protein. CD measurements revealed that, in aqueous solution at neutral pH and in the presence of calcium, the three protein species maintain the helical secondary structure of intact ,-LA, while the tertiary structure is strongly affected by the proteolytic cleavages of the chain. Temperature effects of CD signals in the far- and near-UV region reveal a much more labile tertiary structure in the ,-LA derivatives, while the secondary structure is mostly retained even upon heating. In acid solution at pH 2.0, the three ,-LA variants adopt a conformational state essentially identical to the molten globule displayed by intact ,-LA, as demonstrated by CD measurements. Moreover, they bind strongly the fluorescent dye 8-anilinonaphthalene-1-sulfonate, which is considered a diagnostic feature of the molten globule of proteins. Therefore, the , subdomain can be removed from the ,-LA molecule without impairing the capability of the rest of the chain to adopt a molten globule state. The results of this protein dissection study provide direct experimental evidence that in the ,-LA molten globule only the , domain is structured. [source] The characterization of the semi-solid W/O/W emulsions with low concentrations of the primary polymeric emulsifierINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2005D. Vasiljevic Synopsis Semi-solid multiple W/O/W emulsions with low concentrations (0.8, 1.6 and 2.4% w/w) of lipophilic polymeric primary emulsifier PEG-30-dipolyhydroxystearate (PDHS) have been formulated. Both emulsions, primary and multiple, were prepared with high content of inner phase (,1 = ,2 = 0.8). All the formulations differ only in the lipophilic emulsifier concentration. Evaluating several parameters such as macroscopic and microscopic aspect, droplet size, accelerated stability under centrifugation and flow and oscillatory rheological behaviour, assessed the multiple systems. It is possible to formulate the semi-solid W/O/W multiple emulsions with low concentrations of PDHS as the primary emulsifier. It appeared that the highest long-term stable multiple emulsion with the lowest droplet size, the highest apparent viscosity and highest elastic characteristic, was the sample with the highest concentration (2.4% w/w) of the primary emulsifier. Résumé Les émulsions H/L/H semi-solides ont été formulées avec les concentrations basses (0.8, 1.6 et 2.4% m/m) de l'émulsifiant lipophile polymèrique PEG-30-dipolyhydroxystearate. Les émulsions simples et multiples ont été préparées avec la teneur élevée en phase intérieure (,1 = ,2 = 0.8). La teneur en émulsifiant lipophile était la seule différence entre ces formulations. L'aspect macroscopique et microscopique, la taille de globules, la stabilité physique déterminée par le test de centrifugation ainsi que le comportement rhéologique (rhéologie d'écoulement et oscillatoire) ont permis l'évaluation des émulsions multiples. Il est possible de formuler les émulsions H/L/H semi-solides multiples avec les concentrations basses de PEG-30-dipolyhydroxystearate comme émulsifiant primaire. Il a été découvert que l'émulsion H/L/H multiple avec le plus grand pourcentage (2.4% m/m) de l'émulsifiant primaire a le diamètre de globule le plus petit, la plus grande viscosité apparente et le plus grand module élastique ainsi que la plus longue stabilité. [source] Inverse Monte Carlo procedure for conformation determination of macromoleculesJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 7 2003Mark Bathe Abstract A novel numerical method for determining the conformational structure of macromolecules is applied to idealized biomacromolecules in solution. The method computes effective inter-residue interaction potentials solely from the corresponding radial distribution functions, such as would be obtained from experimental data. The interaction potentials generate conformational ensembles that reproduce thermodynamic properties of the macromolecule (mean energy and heat capacity) in addition to the target radial distribution functions. As an evaluation of its utility in structure determination, we apply the method to a homopolymer and a heteropolymer model of a three-helix bundle protein [Zhou, Y.; Karplus, M. Proc Natl Acad Sci USA 1997, 94, 14429; Zhou, Y. et al. J Chem Phys 1997, 107, 10691] at various thermodynamic state points, including the ordered globule, disordered globule, and random coil states. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 876,890, 2003 [source] Energy density of marine pelagic fish eggsJOURNAL OF FISH BIOLOGY, Issue 6 2002J. Riis-Vestergaard Analysis of the literature on pelagic fish eggs enabled generalizations to be made of their energy densities, because the property of being buoyant in sea water appears to constrain the proximate composition of the eggs and thus to minimize interspecific variation. An energy density of 1.34 J ,l,1 of total egg volume is derived for most species spawning eggs without visible oil globules. The energy density of eggs with oil globules is predicted by x (J ,11) where x is the fractional volume of the oil globule. [source] Calcium phosphate formation on the phosphorylated dental bonding agent in electrolyte solutionJOURNAL OF ORAL REHABILITATION, Issue 1 2004T. Hayakawa summary, The aim of the present study was to study the mineral formation on a phosphorylated dental bonding agent using a mineralization inductive solution. Clearfil Photobond, which contained phosphate monomer, was cured by photo-irradiation and heat treated, and was then immersed in Hanks' balanced salt solution (HBSS) with pH = 7·4 for 1, 3, 5, 7, 14, and 28 days at 37 °C. The white substances were deposited on the phosphorylated polymer, i.e. cured Photobond disk, after the immersion in HBSS. The white substances become visible after 3 days immersion. After 7 days immersion, surface of the phosphorylated polymer disk was almost covered with white substance layers. The measurement of white substances by means of X-ray diffraction, Fourier-transform infrared and electron probe microanalysis revealed that their main component was carbonate-containing hydroxyapatite. Scanning electron microscopy pictures showed that a large number of globules of hydroxyapatite were fused together, and that each globule was composed of a group of numerous thin-film form flakes uniting and/or clustering together. The results obtained in this study concluded that the presence of phosphonic acid and phosphate group of phosphorylated dental bonding agent enhanced the nucleation and growth of hydroxyapatite crystals on its surface. [source] Carotenoids in yellow- and red-fleshed papaya (Carica papaya L)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2003U Gamage Chandrika Abstract Vitamin A deficiency is a disorder of public health importance in Sri Lanka. A recent national survey revealed that 36% of preschool children in Sri Lanka have vitamin A deficiency (serum retinol <0.2 µg ml,1). In view of its well-established association with child morbidity and mortality, this is a reason for concern. One of the main fruits which has been recommended for prevention of vitamin A deficiency in Sri Lanka is papaya (Carica papaya L). In this study the carotenoid profiles of yellow- and red-fleshed papaya were analysed by medium-pressure liquid chromatography (MPLC) and UV-vis spectrophotometry. A section of yellow-fleshed papaya showed small carotenoid globules dispersed all over the cell, whereas in red-fleshed papaya the carotenoids were accumulated in one large globule. The major carotenoids of yellow-fleshed papaya were the provitamin A carotenoids ,-carotene (1.4 ± 0.4 µg g,1 dry weight (DW)) and ,-cryptoxanthin (15.4 ± 3.3 µg g,1 DW) and the non-provitamin A carotenoid ,-carotene (15.1 ± 3.4 µg g,1 DW), corresponding theoretically to 1516 ± 342 µg kg,1 DW mean retinol equivalent (RE). Red-fleshed papaya contained the provitamin A carotenoids ,-carotene (7.0 ± 0.7 µg g,1 DW), ,-cryptoxanthin (16.9 ± 2.9 µg g,1 DW) and ,-carotene-5,6-epoxide (2.9 ± 0.6 µg g,1 DW), and the non-provitamin A carotenoids lycopene (11.5 ± 1.8 µg g,1 DW) and ,-carotene (9.9 ± 1.1 µg g,1 DW), corresponding theoretically to 2815 ± 305 µg kg,1 DW mean RE. Thus the carotenoid profile and organisation of carotenoids in the cell differ in the two varieties of papaya. This study demonstrates that carotenoids can be successfully separated, identified and quantified using the novel technique of MPLC. Copyright © 2003 Society of Chemical Industry [source] On/off switching on polymer conformationMACROMOLECULAR SYMPOSIA, Issue 1 2003Kenichi Yoshikawa Abstract The manner of folding transition from elongated coil to compact globule of single polymer chain is discussed. Based on theoretical consideration, it is argued the semi-flexible polymer chain exhibits large discrete transition on the level of individual single chains, whereas the transition looks continuous, or cooperative, on the ensemble of chains. As the experimental verification, in the present article thermodynamic and kinetic aspects of folding transition of single giant DNA molecules are described. It is shown that rich variety of nano-ordered structures are obtained from single DNA molecules through suitable setup of the experimental conditions. The stability of such nano-structures generated from single polymer chain is discussed in relation to the ordered compact structure with large number of chains in semi-dilute and concentrated polymer solutions. [source] Coil-Globule Collapse in Flexible MacromoleculesMACROMOLECULAR THEORY AND SIMULATIONS, Issue 9 2003Bahattin M. Baysal Abstract The transition of a solvated flexible macromolecular chain from random coil behavior in the , -state to a globular compact form in the collapsed state has been the subject of extensive theoretical and experimental studies. Most of the coil-globule transition studies of macromolecules have concentrated on the prototypical polystyrene-cyclohexane system. However, chain contractions reported in this system have been around 75% of those in the unperturbed , -state. This relatively small decrease in size does not satisfy the criterion for a densely packed, collapsed globule. Experimentally, the collapse from a coil to a true compact globular state has now been established for two flexible macromolecules: poly(N -isopropylacrylamide) in water and poly(methyl methacrylate) in various solvents. In this contribution, we review recent theoretical studies covering phenomenological and Langevin models as well as computer simulations. In addition, we outline recent experimental studies of the coil-globule transition of various flexible polymers, copolymers, and polyelectrolytes. Expansion factor, ,, versus temperature for NaPSS in 4.17 M aqueous NaCl solution. (,): NaPSS-1, (,): NaPSS-2. [source] Nutritional and Physiologic Significance of ,-Lactalbumin in InfantsNUTRITION REVIEWS, Issue 9 2003Bo Lönnerdal PhD ,-Lactalbumin is the major protein in breast milk (20 -25% of total protein) and has been described to have several physiologic functions in the neonatal period. In the mammary gland, it participates in lactose synthesis, thereby creating an osmotic "drag" to facilitate milk production and secretion. ,-Lactalbumin binds divalent cations (Ca, Zn) and may facilitate the absorption of essential minerals, and it provides a well-balanced supply of essential amino acids to the growing infant. During its digestion, peptides appear to be transiently formed that have antibacterial and immunostimulatory properties, thereby possibly aiding in the protection against infection. A novel folding variant ("molten globule state") of multimeric ,-lactalbumin has recently been discovered that has anti-infective activity and enhances apoptosis, thus possibly affecting mucosal cell turnover and proliferation. Cow milk also contains ,-lactalbumin, albeit less than human milk (2-5% of total protein in bovine milk), and protein fractions enriched with ,-lactalbumin may now be added to infant formula to provide some of the benefits of human ,-lactalbumin. [source] Design of a minimal protein oligomerization domain by a structural approachPROTEIN SCIENCE, Issue 12 2000Peter Burkhard Abstract Because of the simplicity and regularity of the ,-helical coiled coil relative to other structural motifs, it can be conveniently used to clarify the molecular interactions responsible for protein folding and stability. Here we describe the de novo design and characterization of a two heptad-repeat peptide stabilized by a complex network of inter- and intrahelical salt bridges. Circular dichroism spectroscopy and analytical ultracentrifugation show that this peptide is highly ,-helical and 100% dimeric under physiological buffer conditions. Interestingly, the peptide was shown to switch its oligomerization state from a dimer to a trimer upon increasing ionic strength. The correctness of the rational design principles used here is supported by details of the atomic structure of the peptide deduced from X-ray crystallography. The structure of the peptide shows that it is not a molten globule but assumes a unique, native-like conformation. This de novo peptide thus represents an attractive model system for the design of a molecular recognition system. [source] The acid-induced folded state of Sac7d is the native statePROTEIN SCIENCE, Issue 10 2000Jennifer L. Bedell Abstract Sac7d unfolds at low pH in the absence of salt, with the greatest extent of unfolding obtained at pH 2. We have previously shown that the acid unfolded protein is induced to refold by decreasing the pH to 0 or by addition of salt (McCrary BS, Bedell J, Edmondson SP, Shriver JW, 1998, J Mol Biol 276:203,224). Both near-ultraviolet circular dichroism spectra and ANS fluorescence enhancements indicate that the acid- and salt-induced folded states have a native fold and are not molten globular. 1H, 15N heteronuclear single quantum coherence NMR spectra confirm that the native, acid-, and salt-induced folded states are essentially identical. The most significant differences in amide 1H and 15N chemical shifts are attributed to hydrogen bonding to titrating carboxyl side chains and through-bond inductive effects. The 1H NMR chemical shifts of protons affected by ring currents in the hydrophobic core of the acid- and salt-induced folded states are identical to those observed in the native. The radius of gyration of the acid-induced folded state at pH 0 is shown to be identical to that of the native state at pH 7 by small angle X-ray scattering. We conclude that acid-induced collapse of Sac7d does not lead to a molten globule but proceeds directly to the native state. The folding of Sac7d as a function of pH and anion concentration is summarized with a phase diagram that is similar to those observed for other proteins that undergo acid-induced folding except that the A-state is encompassed by the native state. These results demonstrate that formation of a molten globule is not a general property of proteins that are refolded by acid. [source] Natural spawning, early development and first feeding of the semicircle angelfish [Pomacanthus semicirculatus (Cuvier, 1831)] in captivityAQUACULTURE RESEARCH, Issue 9 2009Ming-Yih Leu Abstract Successful natural spawning of Pomacanthus semicirculatus in captivity from 11 September to 18 October, 2006 is described for the first time. Each female laid an average of 230 000 eggs during the spawning period. Fertilized eggs were spherical, transparent and buoyant and had a mean diameter of 0.61 ± 0.03 mm (mean ± SD). Embryonic development lasted 18,21 h at 28.5 °C. Newly hatched larvae were 1.35 ± 0.02 mm in total length (TL) with 27 (12+15) myomeres and had an oil globule in the ventroposterior area of the yolk sac. Larvae completed yolk absorption within 3 days post hatching at 2.37 ± 0.05 mm TL. Larvae were fed either 100% microalgae (Nannochloropsis sp.), 100% s-type rotifers (Brachionus rotundiformis), 100% dinoflagellates (Gonyaulax sp.) or different combinations of the three (50%:50%:0%, 30%:35%:35%) to determine the effect of live feed on the survival rate. The survival was significantly (P<0.001) better in larvae fed a combination of diets (30%: 35%: 35%) than others. These results indicate that P. semicirculatus is a potential species for captive-breeding programmes and the use of a combination of diets (microalgae plus s-type rotifers and dinoflagellates) may be a suitable first food for fish larvae. [source] Low versus high molecular weight poly(ethylene glycol)-induced states of stem bromelain at low pH: Stabilization of molten globule and unfolded statesBIOPOLYMERS, Issue 5 2006Basir Ahmad Abstract The effect of low, medium, and high molecular weight poly(ethylene glycol) (e.g., PEG-400, -6000, and -20,000) on the structure of the acid unfolded state of unmodified stem bromelain (SB) obtained at pH 2.0 has been studied by various spectroscopic methods. The conformation of stem bromelain at pH 2.0 exhibits substantial loss of secondary structure and almost complete loss of native tertiary contacts and has been termed the acid unfolded state (AU). Addition of PEG-400 to AU led to an increase in the mean residue ellipticity (MRE) value at 222 nm, indicating formation of ,-helical structure. On the other hand, PEG-6000 and 20,000 led to a decrease in the MRE value at 222 nm, indicating unfolding of the AU state. Interestingly, at 70% (w/v) PEG-400 and 40% (w/v) PEG-20,000, MRE values at 222 nm almost approach the native state at pH 7.0 and the unfolded state (6 M GnHCl) of stem bromelain, respectively. The probes for tertiary structure showed formation of nonnative tertiary contacts in the presence of 70% (w/v) PEG-400, while 40% (w/v) PEG-6000 and 20,000 were found to stabilize the unfolded state of SB. An increase in binding of 1-anilino 8-naphthalene sulfonic acid and a decrease in fractional accessibility of tryptophan residues (fa) compared to AU in the presence of 70% PEG-400 indicate that the PEG-400,induced state has a significant amount of exposed hydrophobic patches and is more compact than AU. The results imply that the PEG-400,induced state has characteristics of molten globule, and higher molecular weight PEGs led to the unfolding of the AU state. © 2005 Wiley Periodicals, Inc. Biopolymers 81: 350,359, 2006 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] A Designed Well-Folded Monomeric Four-Helix Bundle Protein Prepared by Fmoc Solid-Phase Peptide Synthesis and Native Chemical Ligation,CHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2006Gunnar T. Dolphin Dr. Abstract The design and total chemical synthesis of a monomeric native-like four-helix bundle protein is presented. The designed protein, GTD-Lig, consists of 90 amino acids and is based on the dimeric structure of the de novo designed helix-loop-helix GTD-43. GTD-Lig was prepared by the native chemical ligation strategy and the fragments (45 residues long) were synthesized by applying standard fluorenylmethoxycarbonyl (Fmoc) chemistry. The required peptide,thioester fragment was prepared by anchoring the free ,-carboxy group of Fmoc-Glu-allyl to the solid phase. After chain elongation the allyl moiety was orthogonally removed and the resulting carboxy group was functionalized with a glycine,thioester followed by standard trifluoroacetic acid (TFA) cleavage to produce the unprotected peptide,thioester. The structure of the synthetic protein was examined by far- and near-UV circular dichroism (CD), sedimentation equilibrium ultracentrifugation, and NMR and fluorescence spectroscopy. The spectroscopic methods show a highly helical and native-like monomeric protein consistent with the design. Heat-induced unfolding was studied by tryptophan absorbance and far-UV CD. The thermal unfolding of GTD-Lig occurs in two steps; a cooperative transition from the native state to an intermediate state and thereafter by noncooperative melting to the unfolded state. The intermediate exhibits the properties of a molten globule such as a retained native secondary structure and a compact hydrophobic core. The thermodynamics of GuHCl-induced unfolding were evaluated by far-UV CD monitoring and the unfolding exhibited a cooperative transition that is well-fitted by a two-state mechanism from the native to the unfolded state. GTD-Lig clearly shows the characteristics of a native protein with a well-defined structure and typical unfolding transitions. The design and synthesis presented herein is of general applicability for the construction of large monomeric proteins. [source] Dermoscopic Features of Mucinous Carcinoma of the SkinDERMATOLOGIC SURGERY, Issue 8 2004Rie Yoshida Background. Dermoscopic features of nonpigmented skin lesions are seldom reported; dermoscopy might be useful in speculating pathologic features in the upper dermis. Objective. The objective was to identify additional dermoscopic criteria. Methods. Dermoscopy of the mucinous carcinoma of the skin occurring on the cheek of a 69-year-old man was performed. Results. We have shown characteristic dermoscopic features of whitish network and light-brown globules and they correspond to the pathologic findings of fibrous septum and mucinous deposition, respectively. Discussion. Dermoscopic examination seemed useful as an adjunct to the diagnosis of this rare nonpigmented malignant neoplasm. [source] Interobserver Agreement on Dermoscopic Features of Pigmented Basal Cell CarcinomaDERMATOLOGIC SURGERY, Issue 7 2002Ketty Peris MD background. A dermoscopic method based on the absence of a pigment network and the presence of at least one of six positive features has been described for diagnosis of pigmented basal cell carcinoma (BCC). objective. To evaluate the observers' global agreement and interobserver agreement on each dermoscopic parameter of the method recently proposed. methods. Dermoscopic images of 56 pigmented BCCs were examined by five observers with different degrees of experience in dermoscopy. results. An overall full agreement was reached for the absence of pigment network (k = 1). Very good agreement was detected for the presence of spoke wheel areas (k = 0.85) and arborizing vessels (k = 0.72), and good agreement was shown for ulceration (k = 0.49) and multiple blue-gray globules (k = 0.41). No agreement was identified on large blue-gray ovoid nests (k = 0.28) and leaflike areas (k = 0.26). conclusion. We confirm the reproducibility of the method and show that ulceration, spoke wheel areas, and arborizing tel- angiectases represent the most robust positive parameters. [source] Hyaline globules in ectopic decidua in a pregnant woman with cervical squamous cell carcinomaDIAGNOSTIC CYTOPATHOLOGY, Issue 9 2009M.I.A.C., Muralee Dharan M.D. Abstract Decidual reaction in pelvic lymph nodes has been increasingly documented during pregnancy. This may pose diagnostic difficulty during intraoperative frozen section (FS) and cytological consultation in women undergoing surgical procedures for cervical Squamous cell carcinoma (SCC). A 34-year-woman diagnosed to have invasive SCC (stage IB1) of the cervix at 14th week of her first pregnancy underwent abdominal radical trachelectomy and pelvic lymphadenectomy at 22 weeks of gestation. Cytological smears of two of the lymph nodes from intraoperative FS revealed isolated eosinophilic hyaline globules (HG) measuring 45,50 microns, in addition to large polygonal cells with amphophilic cytoplasm and hypochromatic nuclei and occasional squamous-looking cells with atypical hyperchomatic nuclei. These findings posed a diagnostic dilemma at intraoperative consultation and no definitive diagnosis was rendered. The formlin-fixed, paraffin-embedded histological sections of the same lymph nodes showed ectopic decidua with no evidence of metastatic SCC. Decidual cells are a cause of concern for both cytologists and histopathologists. In pregnant women complicated by cervical cancer intraoperative evaluation of pelvic lymph nodes is of utmost importance in order to adopt the optimal conservative treatment modality. In the absence of clear cut evidence of malignancy, a diagnosis of metastatic SCC should not be rendered. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Pleomorphic adenoma: Cytologic variations and potential diagnostic pitfallsDIAGNOSTIC CYTOPATHOLOGY, Issue 1 2009Uma Handa M.D. Abstract The diverse morphological features encountered in pleomorphic adenoma (PA) may cause diagnostic errors in fine needle aspiration cytology (FNAC). The present study was performed to evaluate the variations in the cytological features of pleomorphic adenoma and to assess the efficacy of FNAC in its diagnosis. Fifty cases diagnosed as PA on FNAC were retrieved from the records of the Pathology Department. Cytologic smears and sections were reviewed and the cytologic diagnoses were compared with the definitive histologic diagnoses. In cases correctly diagnosed on aspiration, morphological variables like patterns of the epithelial component, type and extent of the mesenchymal matrix, metaplastic cells, hyaline globules, cystic change, giant cells, crystalline deposits, nuclear inclusions/grooves, and nuclear atypia were evaluated. The extreme diversity in morphologic features seen in histologic sections was reflected in the smears of PA. Metaplastic changes were observed more frequently in sections, while nuclear changes like inclusions/grooves were more commonly seen in smears. Other morphological features like cylindromatous pattern, giant cells and crystalline deposits were observed with equal frequency in smears and sections. Cytohistologic agreement was present in 45 of the 50 cases (90%). In 5 cases diagnosed as pleomorphic adenoma on FNAC, the histology revealed 1 case each of schwannoma, perineurioma, ectomesenchymal chondromyxoid tumor of tongue, adenoid cystic carcinoma and mucoepidermoid carcinoma. FNAC is a fairly accurate pre-operative procedure for the diagnosis of PA. The cytopathologist needs to be aware of the cytologic variations in pleomorphic adenoma so as to avoid diagnostic errors. Diagn. Cytopathol. 2009. © 2008 Wiley-Liss, Inc. [source] The characterization of the semi-solid W/O/W emulsions with low concentrations of the primary polymeric emulsifierINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2005D. Vasiljevic Synopsis Semi-solid multiple W/O/W emulsions with low concentrations (0.8, 1.6 and 2.4% w/w) of lipophilic polymeric primary emulsifier PEG-30-dipolyhydroxystearate (PDHS) have been formulated. Both emulsions, primary and multiple, were prepared with high content of inner phase (,1 = ,2 = 0.8). All the formulations differ only in the lipophilic emulsifier concentration. Evaluating several parameters such as macroscopic and microscopic aspect, droplet size, accelerated stability under centrifugation and flow and oscillatory rheological behaviour, assessed the multiple systems. It is possible to formulate the semi-solid W/O/W multiple emulsions with low concentrations of PDHS as the primary emulsifier. It appeared that the highest long-term stable multiple emulsion with the lowest droplet size, the highest apparent viscosity and highest elastic characteristic, was the sample with the highest concentration (2.4% w/w) of the primary emulsifier. Résumé Les émulsions H/L/H semi-solides ont été formulées avec les concentrations basses (0.8, 1.6 et 2.4% m/m) de l'émulsifiant lipophile polymèrique PEG-30-dipolyhydroxystearate. Les émulsions simples et multiples ont été préparées avec la teneur élevée en phase intérieure (,1 = ,2 = 0.8). La teneur en émulsifiant lipophile était la seule différence entre ces formulations. L'aspect macroscopique et microscopique, la taille de globules, la stabilité physique déterminée par le test de centrifugation ainsi que le comportement rhéologique (rhéologie d'écoulement et oscillatoire) ont permis l'évaluation des émulsions multiples. Il est possible de formuler les émulsions H/L/H semi-solides multiples avec les concentrations basses de PEG-30-dipolyhydroxystearate comme émulsifiant primaire. Il a été découvert que l'émulsion H/L/H multiple avec le plus grand pourcentage (2.4% m/m) de l'émulsifiant primaire a le diamètre de globule le plus petit, la plus grande viscosité apparente et le plus grand module élastique ainsi que la plus longue stabilité. [source] Nutritional and therapeutic value of fermented caprine milkINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2010ANAC, VEDRAN SLA Caprine milk is a nutritional and therapeutic food. The unique and beneficial characteristics of caprine milk that are superior to bovine milk include: better digestibility; greater buffering capacity; fat globules that are smaller in diameter and better distributed in the milk emulsion; higher content of short-chain fatty acids in the milk fat; higher content of zinc, iron and magnesium; stronger lactoperoxidase (antimicrobial) system as well as better immunological and antibacterial characteristics. The larger amounts of some minerals, such as calcium, zinc and magnesium, in caprine milk may influence the growth of lactic acid bacteria since they are a normal part of some enzymatic complexes involved in lactose fermentation. The higher whey protein content could also be significant because Lactobacillus acidophilus and bifidobacteria grow better in the presence of higher levels of some amino acids (valine, glycine, hystidine). The use of caprine and ovine milk in cheesemaking is well known, but the production of fermented caprine milk via probiotics has not yet been developed, although many studies have highlighted the requirements for production of that kind of healthy food. During fermentation caprine milk loses its characteristic ,goaty' taste, which is unacceptable to many consumers. Moreover, the nutritive value of caprine milk increases during fermentation. The rise in the number of goat farms in Croatia has created the need to find other products that can be produced using caprine milk. According to the present situation in Croatia, there is no real possibility of producing fermented caprine milk for the global market, but many studies of fermented caprine milk have been performed. [source] Dermoscopic patterns of superficial basal cell carcinomaINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2008Massimiliano Scalvenzi MD Background, Superficial basal cell carcinoma (BCC) presents as a scaly, pink to red,brown patch and is predominantly located on the trunk. Clinical diagnosis may not be always easy and implicates a variety of differential diagnoses; in this situation dermoscopy has been reported improving the diagnostic accuracy. This study investigated dermoscopic patterns of superficial BCC focalizing the most specific and frequent structures in order to improve the diagnostic accuracy. Limitations, Study population referred to skin lesion clinic. Methods, Dermoscopic patterns of 42 superficial BCCs were analyzed and photographed. These cases represented the 8% of all BCCs excised in our Department between 2005 and 2006. Results, Dermoscopic structures observed in the 42 superficial BCCs consisted of shiny white to red areas (100%), "erosions" (78.6%), short fine telangiectasias (SFTs) (66.6%), leaf-like areas (16.6%), arborizing telangiectasias (14.3%), blue,gray globules (14.3%) and large blue,gray ovoid nests (4.7%). Conclusions, Our study identifies the presence of shiny white to red areas, SFTs and "erosions" as main dermoscopic criteria of superficial BCC. Other dermoscopic features, such as leaf-like areas, arborizing telangiectasias, blue,gray globules and large blue,gray ovoid nests, are not strongly associated with the diagnosis of superficial BCC but they are useful in the differential diagnosis from other pigmented and nonpigmented skin lesions. [source] Juvenile hyaline fibromatosis: a case report and review of the literatureINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2004Jean E. Thomas MD Background, Juvenile hyaline fibromatosis (JHF) is a rare, inherited condition characterized by tumor-like growth of hyalinized fibrous tissue on the head and neck, joint contractures, and gingival hypertrophy. There may be marked clinical heterogeneity. Methods, We present a case of a 3-year-old Haitian boy with multiple firm nodules on the scalp and chin without joint contractures or gingival hypertrophy. Family history was not available. Results, Biopsy specimens from three scalp nodules were processed with routine and immunohistochemical stains. The matrix was periodic acid Schiff (PAS) and Alcian blue positive. The cellular stromal component was positive for vimentin and scattered factor XIIIa positive cells were found. Osteoclast-like giant cells were also noted, and stained for CD68. Conclusions, Our patient had the nodular growths on the scalp and face that are characteristically found in JHF. Microscopic examination confirmed the diagnosis and showed scattered intracytoplasmic and extracellular eosinophilic globules in three separate biopsy specimens. These were positive with PAS. [source] Living without mitochondria: spermatozoa and spermatogenesis in two species of Urodasys (Gastrotricha, Macrodasyida) from dysoxic sedimentsINVERTEBRATE BIOLOGY, Issue 1 2007Maria Balsamo Abstract. The spermatozoa of two species of Macrodasyida (Gastrotricha), Urodasys anorektoxys and U. acanthostylis, show an ultrastructural organization diverging from one another and from other gastrotrichs: their main peculiarity is in the absence of mitochondria. In U. anorektoxys, the acrosome is a long, twisted column inserted into the nucleus, which is basally cylindrical, and the flagellum shows rows of peculiar, large globules parallel to the axonemal doublets. In U. acanthostylis, the acrosome is completely cork-screwed and surrounds the nucleus, and the tail shows columnar accessory fibers. At present, the absence of mitochondria in the mature sperm, and the peculiar fingerprint aspect of condensed chromatin are the only traits shared by the two species. The features of the spermatozoa of these two species of Urodasys widen the range of different models of gastrotrich spermatozoa, and place the genus in a peculiar position, from the spermatological point of view, within the Macrodasyida. The loss of mitochondria in mature spermatozoa is possibly related to either the dysoxic habitat of the two species or a peculiar fertilization mechanism. [source] Anatomy of the lactating human breast redefined with ultrasound imagingJOURNAL OF ANATOMY, Issue 6 2005D. T. Ramsay Abstract The aim of this study was to use ultrasound imaging to re-investigate the anatomy of the lactating breast. The breasts of 21 fully lactating women (1,6 months post partum) were scanned using an ACUSON XP10 (5,10 MHz linear array probe). The number of main ducts was measured, ductal morphology was determined, and the distribution of glandular and adipose tissue was recorded. Milk ducts appeared as hypoechoic tubular structures with echogenic walls that often contained echoes. Ducts were easily compressed and did not display typical sinuses. All ducts branched within the areolar radius, the first branch occurring 8.0 ± 5.5 mm from the nipple. Duct diameter was 1.9 ± 0.6 mm, 2.0 ± 90.7 mm and the number of main ducts was 9.6 ± 2.9, 9.2 ± 2.9, for left and right breast, respectively. Milk ducts are superficial, easily compressible and echoes within the duct represent fat globules in breastmilk. The low number and size of the ducts, the rapid branching under the areola and the absence of sinuses suggest that ducts transport breastmilk, rather than store it. The distribution of adipose and glandular tissue showed wide variation between women but not between breasts within women. The proportion of glandular and fat tissue and the number and size of ducts were not related to milk production. This study highlights inconsistencies in anatomical literature that impact on breast physiology, breastfeeding management and ultrasound assessment. [source] Polymer hydration and microphase decomposition in poly(N -vinylcaprolactam),water complexJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2003Vassili Lebedev Poly(N -vinylcaprolactam) (PVCL) is a synthetic analogue of biomolecules (enzymes, proteins). It demonstrates a specific hydration and undergoes a coil,globule transition. The PVCL,D2O system (PVCL mass M = 106) has been investigated by small-angle neutron scattering (SANS) at T = 296,316,K to identify the structural features of the collapse at concentration C = 0.5,wt% near the threshold of the coil overlap. (The collapse leads to the segregation of the phase enriched with polymer at T > 305,K). The SANS experiments at q = 0.1,5,nm,1 (scales from monomer unit to globule gyration radius RG, 16,nm) have revealed a stretched coil,globule transformation in the range 305,309,K. Using high-resolution SANS (q = 0.002,0.02 nm,1) the globule association to form fractal structures (sponge-like) of surface dimension DF, 2.4,2.6 was examined. The coexistence of globules and disordered chains (regions ,5,10,nm) was found. The growth of the content of globular phase was induced by the conformational transition in disordered molecular fragments from coiled (dimension D, 1.8) to stretched chains (D, 1.2). [source] Synthesis and characterization of novel saponified guar-graft-poly(acrylonitrile)/silica nanocomposite materialsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007Vandana Singh Abstract The combination of carbohydrates with silicon-based ceramic materials offers attractive means of production for high performance materials. Present article describes the synthesis of novel nanocomposites out of SiO2 and saponified guar-graft-poly(acrylonitrile) (SG). Tetraethoxysilane was used as the precursor for silica and growth of SiO2 phase was allowed concurrently in the presence of SG. The material so obtained was thermally treated at 80°C, 160°C, 500°C, and 900°C to study the effect of thermal curing on its properties. During the curing process, silanol surface groups of silica globules reacted to create the reinforced SiO2 -SG substance. It was observed that at 900°C, the SiO2 phase crystallized out in tetragonal shape (similar to Cristobalite form of silica) in presence of SG. The chemical, structural and textural characteristics of the composites were determined by FTIR, XRD, TGA-DTA, SEM and BET studies. The materials were also evaluated as efficient Zn2+ metal binder. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 536,544, 2007 [source] Energy density of marine pelagic fish eggsJOURNAL OF FISH BIOLOGY, Issue 6 2002J. Riis-Vestergaard Analysis of the literature on pelagic fish eggs enabled generalizations to be made of their energy densities, because the property of being buoyant in sea water appears to constrain the proximate composition of the eggs and thus to minimize interspecific variation. An energy density of 1.34 J ,l,1 of total egg volume is derived for most species spawning eggs without visible oil globules. The energy density of eggs with oil globules is predicted by x (J ,11) where x is the fractional volume of the oil globule. [source] GRINDING SPRAY-DRIED MILK POWDER NEAR the GLASS TRANSITION TEMPERATUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2003GREGORY R. ZIEGLER ABSTRACT The fine grinding of chocolate is typically accomplished on five-roll mills. Chocolate manufacturers consider milk powder, a component of milk chocolate, difficult to grind. Spray-dried milk powders comprise a glassy lactose matrix in which fat globules, air vacuoles and protein are entrapped. the glassy-rubbery transition in commercial milk powders usually lies between 60,70C, depending on the moisture content. A mixture of 60% wt/wt commercial whole milk powder, Tg, 60C, and 40% wt/wt cocoa butter was ground in a three-roll refiner at temperatures of 40, 50, 60, 70 and 75C. Below Tg the particles exhibited brittle fracture, while above Tg plastic deformation was evident and particles became highly asymmetric. the amount of fat liberated from the lactose matrix, so-called free fat, particle density, and mean particle size increased with grinding temperature. However, the Casson yield value and plastic viscosity of finished "white chocolate" coatings, manufactured to a constant free fat content, increased with grinding temperature, suggesting an influence of particle shape on flow behavior. [source] Mineralized dermal layer of the Brazilian tree-frog Corythomantis greeningiJOURNAL OF MORPHOLOGY, Issue 1 2001E. Katchburian Abstract Some species of anuran amphibians possess a calcified dermal layer (the Eberth-Kastschenko layer) located between the "stratum spongiosum" and the "stratum compactum." This layer consists of calcium phosphate deposits, proteoglycans, and glycosaminoglycans. Although regarded as a protective layer against desiccation, a calcium reservoir, or possibly a remnant of a dermal skeleton present in anuran ancestors, very little is known about its origin, structure, and function. Thus, we studied the structure and composition of the mineralized dermal layer of Corythomantis greeningi, a peculiar hylid from the Brazilian semiarid region (caatinga), using conventional and cryosubstitution methods combined with transmission, scanning, and analytical electron microscopy. Results show that the dermal layer consists of dense, closely juxtaposed, globular structures. Although the electron opacity of the globules was variable, depending on the type of preparation, crystal-like inclusions were present in all of them, as confirmed by dark field microscopy. Electron probe X-ray microanalysis showed calcium, phosphorus, and oxygen, and electron diffraction revealed a crystalline structure comparable to that of a hydroxyapatite. J. Morphol. 248:56,63, 2001. © 2001 Wiley-Liss, Inc. [source] Calcium phosphate formation on the phosphorylated dental bonding agent in electrolyte solutionJOURNAL OF ORAL REHABILITATION, Issue 1 2004T. Hayakawa summary, The aim of the present study was to study the mineral formation on a phosphorylated dental bonding agent using a mineralization inductive solution. Clearfil Photobond, which contained phosphate monomer, was cured by photo-irradiation and heat treated, and was then immersed in Hanks' balanced salt solution (HBSS) with pH = 7·4 for 1, 3, 5, 7, 14, and 28 days at 37 °C. The white substances were deposited on the phosphorylated polymer, i.e. cured Photobond disk, after the immersion in HBSS. The white substances become visible after 3 days immersion. After 7 days immersion, surface of the phosphorylated polymer disk was almost covered with white substance layers. The measurement of white substances by means of X-ray diffraction, Fourier-transform infrared and electron probe microanalysis revealed that their main component was carbonate-containing hydroxyapatite. Scanning electron microscopy pictures showed that a large number of globules of hydroxyapatite were fused together, and that each globule was composed of a group of numerous thin-film form flakes uniting and/or clustering together. The results obtained in this study concluded that the presence of phosphonic acid and phosphate group of phosphorylated dental bonding agent enhanced the nucleation and growth of hydroxyapatite crystals on its surface. [source] | |||||||||||||||||||||||||||||||||||||